Download Psychotropic PRN medication in inpatient psychiatric care: a literature review

Psychotropic PRN
medication in inpatient
psychiatric care: a
literature review
Report from the Conflict and Containment
Reduction Research Programme
Steve Wright, Institute of Psychiatry, Kings College London
Duncan Stewart, Institute of Psychiatry, Kings College London
Len Bowers, Institute of Psychiatry, Kings College London
September 2012
Section of Mental Health Nursing
Institute of Psychiatry
London SE5 8AF
1
CONTENTS
1.
2.
2.5
2.6
2.7
INTRODUCTION
4
1.1
1.2
1.3
1.4
1.5
4
4
4
5
5
Aim
Search method
Definition
Quality appraisal
Data abstraction and synthesis
RESULTS
5
2.1
2.2
2.3
2.4
Prevalence and incidence of PRN use
Good practice in PRN use
Clinical decision-making in PRN use
Demographic profile of patients
5
9
11
13
2.4.1
2.4.2
2.4.3
2.4.4
2.4.5
2.4.6
2.4.7
13
14
14
15
15
15
Age
Gender
Ethnicity
Interactions between age and gender
Marital status
Employment status/education
Other sociodemographic variables and PRN
use
2.4.8 Diagnosis
2.4.9 Admission status
2.4.10 Length of inpatient stay
2.4.11 Previous admissions
2.4.12 Chronic physical illness or disability
16
16
17
17
18
18
Characteristics of patients receiving repeated PRN doses
Relationship of PRN to regular medication
Temporal ecology of PRN administration
18
19
21
2.7.1
2.7.2
2.7.3
2.8
2.9
2.10
2.11
2.12
Time of day
Day of week
Month
Antecedents of PRN use
Outcomes of PRN use
Relationship of PRN use to other containment methods
Alternatives to PRN and their use
2.11.1 Regular medication as an alternative to
PRN medication
2.11.2 Non-pharmacological alternatives
2.11.3 Is PRN medication actually necessary?
The case for prohibition
Perceptions of PRN use: staff, patients and others
21
22
22
22
26
28
29
29
30
35
36
2
3
4
DISCUSSION
38
3.1
3.2
3.3
38
39
40
Summary
PRN use and the City Model
Lessons for future research
REFERENCES
42
3
1.
INTRODUCTION
1.1
Aim
The aim of the review was to evaluate the literature on ‘as required’ (‘pro re nata’ or
PRN) psychotropic medication in order to discover evidence which supported or did
not support the City Model, and to discover if it highlighted any points not addressed
by the City Model.
Psychotropic medication is a cornerstone of the treatment of mental disorders, and in
inpatient settings it is a key part of the treatment function of admission (Bowers,
2005). Because such medication can take several weeks to be effective (particularly
antipsychotic medication), additional medication (which is to say, PRN medication) is
commonly needed in the interim in case of agitation and distress. Indeed, between
20% and 50% of psychiatric inpatients receive at least one dose of PRN psychotropic
medication during their admission (Chakrabati et al, 2010). The most frequently
administered PRN psychotropic drugs are antipsychotics, anxiolytics, hypnotics, and
anticholinergics. Despite this important role in the management of acute psychiatric
symptoms, the use of PRN psychotropic medication has been criticised on the
grounds that it increases risks of morbidity, can be inappropriately used, may result in
above-recommended dosages or polypharmacy, and can complicate the assessment
of the efficacy of regular scheduled medications, while there are nonpharmacological alternatives to PRN psychotropic medication which are effective and
associated with fewer side-effects (Hilton & Whiteford, 2008).
1.2
Search method
Electronic searches of the main databases were conducted to locate empirical
studies of PRN medication in English published between 1960 and 2011. The
databases searched were: PsycInfo, Cochrane, Medline, EMBASE Psychiatry,
CINAHL and the British Nursing Index. Key words utilised were PRN or pro re nata or
as needed medication or as needed drugs or if needed medication or if needed
drugs. Another search was conducted using the key words psychiatr* or mental,
inpatient or hospital or ward, psychiatr* and mental, and also inpatient and hospital
and ward. The results of the last two searches were then combined. This total was
combined with the first search which identified 120 references, which were then
inspected for relevance. Review articles, theses, books, and papers concerned with
non-psychotropic PRN (e.g. analgesics) or specialities other than inpatient
psychiatry, or where PRN medication was included in the calculations of total
chlorpromazine equivalents but the prescription and administration was not otherwise
investigated were omitted. In total, 84 empirical papers were identified, and all but
one (which the British Library was unable to obtain) were reviewed.
1.3
Definition
For the purpose of this review, PRN medication is defined as unscheduled
psychotropic medication which, when prescribed, may be administered at the nurses’
discretion if the need for it arises. The review focuses on orally-administered PRN
medication, although intramuscular PRN medication is sometimes included alongside
orally-administered PRN medication in some studies.
4
1.4
Quality appraisal
Two of the studies reviewed were trials, but used repeated-measures designs rather
than the random allocation of participants to treatment and control arms of a
conventional RCT. Thirteen studies were cross-sectional cohort studies using a
variety of methodologies (prospective observation, prospective crossover,
prospective casenote audit, and point-prevalence surveys). Thirty-two studies were
case-control or other comparisons, and 18 were natural experiments without controls.
Seven studies were qualitative, again using a variety of methodologies (including
interviews, vignettes, and Delphi method), another seven were questionnaire surveys
of knowledge or attitudes, and there were three single-case reports. Thirty-seven
studies used retrospective casenote audit as their primary data collection method,
which is vulnerable to recording biases. The quality of casenote entries can also be
extremely variable, and they may not contain a sufficient level of detail for research
purposes. Nineteen of the studies reviewed were conducted in the UK.
The studies typically had small samples. In the 69 studies involving patients
(excluding the single-case studies), the number of participants in them ranged from
five to 3,942, with a median of 100 (15 studies collected data on fewer than 50
patients, and five collected data on more than 1,000). For the 11 studies involving
non-patients (clinicians, etc.) the number of participants ranged from 18 to 1,226,
with a median of 36 (two studies collected data on over 100 non-patient participants,
and one on more than 1,000).
Twenty-seven studies collected data on patients from only one ward, and 28
collected data from patients on more than one ward in the same hospital. Ten studies
collected data from patients from more than one hospital site in the same region, and
two collected data from more than one geographical region.
In summary, few of the studies employed controls, over a third collected data from an
unreliable source, a quarter had fewer than 50 participants, and over 80% of them
collected data from a single participating hospital (and in half of theses studies from
only one ward), meaning that the data is unlikely to be generalisable.
1.5
Data abstraction and synthesis
A structured data extraction tool was created with various headings including sample,
methodology, admission status, age, gender, ethnicity, ward type,
antecedents/causes, patients’ views, staff views, etc. Where published papers
provided empirical evidence, this was entered on the tool. The information contained
in the resultant matrix was then summarised for the purposes of this review.
2.
RESULTS
2.1
Prevalence and incidence of PRN use
As mentioned above, the use of PRN psychotropic medication in inpatient psychiatric
units is very common. Table 1 below summarises standardised patient-based rates
of PRN use, which are based upon how many patients in a study received PRN
medication at least once. These patient-based rates therefore relate to the
epidemiological concept of prevalence (the total number of cases in a population).
Table 2 summarises the event-based rates, which are based upon the total number
of times PRN medication was administered during the study period. These eventbased rates therefore correspond to the epidemiological concept of incidence (the
rate of occurrence). Overall patient- and event-based rates are presented in the
5
tables, as well as rates which are standardised in relation to number of admissions
per month and length of inpatient stay where this information is presented in the
studies. None of the studies reviewed gave information about the size of the
population served by the units studied, making it impossible to calculate populationbased rates.
Overall patient-based rates of PRN use range from 4% to 100% of the patients in the
study receiving PRN medication at least once, with a mean rate of 52.58%.
Table 1.
Paper
Standardised patient-based rates of PRN administration reported
in the studies reviewed.
Patient-based rates
Per 100
Per 100
admissions
occupied
per month
bed-days
Ward type
Overall
44.49%
USA
VA psychiatric
hospital
Child/adolescent
unit
General
psychiatric wards
General hospital
England
MSU
46.88%
Canada
University
teaching hospital
64%
4.21
USA
Specialist unit for
aggressive
patients
Long-stay unit
100%
0.27
Country
Mason et al,
1974
Vitiello et al,
1987
Craven et al,
1987
Wise et al,
1989
McLaren et
al, 1990
O'Reilly &
Rusnak,
1990
Ratey et al,
1993
USA
Cooney,
1993
Canada
Craig &
Bracken,
1995
Haller et al,
1996
USA
Acute, rehab, and
elderly wards
USA
Locked inpatient
unit
Milton et al,
1998
Kaplan &
Busner,
1997
Walker, R.
(1991).
Voirol et al,
1999
England
Acute and
forensic
Child inpatient
unit
Bernard &
Littlejohn,
England
USA
Canada
USA
USA
Switzerland
General hospital
psychiatric unit
One closed
psychiatric ward,
one open
psychiatric ward
Adolescent unit
85.71%
0.12
75%
54%
57.14%
(compulsive
water-drinkers)
28.57% (controls)
22.92%
39.13
2.13
22.92
74% (presmoking ban
average/ month)
60% (postsmoking ban
average/ month)
4% (1994)
5% (1996)
64%
7.14 (presmoking ban
average/month)
4.29 (postsmoking ban
average/month)
70%
69% (closed
ward) 62% (open
ward)
60.4%
59.9
6
2000
Usher et al,
2001
Thapa, et al,
2003
O'Brien &
Cole, 2004
Hales &
Gudjonsson,
(2004).
Zullino et al,
2004.
Australia
Acute
63.33%
63.3
USA
3 acute units
78.48%
78.48
Australia
Acute
17.05%
17.05
England
MSU
Switzerland
Detox unit
Russell et al,
2006
Goedhard et
al, 2007
Curtis et al,
2007
Davies et al,
2007
India
Child/adolescent
service
Three long-stay
wards
Acute
Dean et al,
2007
Australia
6 acute wards, 3
functional
psychogeriatric
wards
Adolescent unit
SteinParbury et
al, 2008
Baker et al,
2008
Chaichan,
2008
Australia
Acute
29.23% (preintervention)
23.26% (post
intervention)
83.8%
England
Acute
80%
Thailand
Acute
65.71 (preintervention)
56.01 (postintervention)
Philip et al,
2008
Dean et al,
2009
Winterfield
et al, 2009
Baker et al,
2010
Swart et al
2011
USA
Private hospital
65.7% (preintervention)
56.1% (postintervention)
69.8%
Australia
Adolescent unit
France
Child/adolescent
unit
11 older adult
wards
Regional
children’s unit
45.45% (time 1)
25.56% (time 2)
27.7%
44.69 (time 1)
25.59 (time 2)
27.66
1.18
50.31
0.6
Australia
Australia
England
England
Canada
4.29
64.29
47.45%
(anxiolytics)
54.55%
(hypnotics)
26.21
(prescriptions)
51.2%
47.47
(anxiolytics)
54.56
(hypnotics)
26.09
(prescriptions)
45.49
73.44%
73.44
5.1 (anxiolytics)
5.87
(hypnotics)
0.76
(prescriptions)
0.3
44.27%
83.8
0.04
1.14
16.9%
50.3%
Event-based rates of PRN medication use range from 0.61% to 5632.12%. The
distribution of rates is J-shaped, heavily skewed towards smaller values, with a
median event-based value of 365.42%.
7
Table 2.
Paper
Standardised event-based rates of PRN administration reported
in the studies reviewed.
Country
Overall
Ward type
Vitiello et
al, 1987
Craven et
al, 1987
USA
Child/adolescent
unit
General
psychiatric
wards
General hospital
psychiatric unit
2577.55%
Thorward
&
Birnbaum,
1989
Canada
McLaren et
al, 1990
Garrison et
al, 1990
Walker,
1991
Ratey et al,
1993
England
MSU
712.5%
USA
Child psychiatric
unit
General hospital
psychiatric unit
Specialist unit
for aggressive
patients
2.85
Cooney,
1993
Canada
Long-stay unit
Fishel et al,
1994
USA
Craig &
Bracken,
1995
Hoff et al
1996
USA
1 locked
university
medical centre
inpatient unit, 1
locked the other
at a state
hospital
psychiatric unit
Acute, rehab,
and elderly
wards
Rehab
Gray et al,
1996
Kaplan &
Busner,
1997
England
Canada
USA
USA
USA
USA
Two acute
wards
Child inpatient
unit
Event-based rates
Per 100
Per 100
admissions occupied bedper month
days
3.51
2029.333%
10.41% (presmoking ban)
12.74% (postsmoking ban)
93.23 (presmoking
ban) 97.38
(postsmoking
ban)
107.83 (presmoking ban)
142.26 (postsmoking ban)
284.85
6.9
499.28%
1276% (pretreatment)
964% (posttreatment)
152.38%
(compulsive
water-drinkers)
76.19%
(controls)
323.64% (state
hospital)
462.96%
(medical centre)
0.61%
1380%
(baseline) 950%
(after 3 months
of treatment)
3.5 (pretreatment)
2.64 (posttreatment)
61
15.16
(baseline)
10.44 (after 3
months of
treatment)
1011.36%
744.67%
8
Gray et al,
1997
Bernard &
Littlejohn,
2000
Usher et al,
2001
Thapa, et
al, 2003
O'Brien &
Cole, 2004
Alexander,
2006
Thomas et
al 2006
England
1011.4%
England
Two acute
wards
Adolescent unit
407.2%
404
Australia
Acute
297.77%
287.77
USA
3 acute units
812.56
812.56
Australia
Acute
135.23%
135.23
England
Two acute
wards
2 locked highdependence
units
Rehab
516.66%
Australia
Megna et
al, 2007
USA
Goedhard
et al, 2007
Curtis et al,
2007
Davies et
al, 2007
Australia
SteinParbury et
al, 2008
Baker et al,
2008
Chaichan,
2008
Australia
England
Three long-stay
wards
Acute
241.03 (control)
107.69
(treatment)
761.54%
(baseline)
161.54% (after 6
months of
treatment)
35.42%
3543.8
482.81%
4.83
28.48%
Australia
6 acute wards, 3
functional
psychogeriatric
wards
Acute
England
Acute
1382.86%
Thailand
Acute
154.29% (preintervention)
136.59 (postintervention)
Smith et al,
2008
USA
9 state
psychiatric
hospitals
Dean et al,
2009
Australia
Winterfield
et al, 2009
Baker et al,
2010
Swart et al
2011
France
England
Canada
921%
5635.12 (first
month of study)
1156.46 (final
month of study)
Adolescent unit
223.21% (time
1) 110.73%
(time 2)
Child/adolescent 0.81%
unit
11 older adult
49.35%
wards
Regional
59.5%
children’s unit
44.1
49.47 (control)
11.05
(treatment)
4.17 (baseline)
0.89 (after 6
months of
treatment)
921
20.83
45
19.76
154.29 (preintervention)
136.59
(postintervention)
221.24 (time
1) 108.23
(time 2)
80.85
3.44
494.85
5.95
9
More than three-quarters of the event-based rates are in excess of 100%, which
indicates that some patients received more than one dose of PRN medication. The
clinical characteristics of patients receiving large numbers of PRN administrations are
summarised below.
2.2
Good practice in PRN use
A Delphi study by Baker et al (2007a) explored multidisciplinary opinions concerning
issues and best practice for the prescribing and administration of psychotropic PRN
medication in acute inpatient psychiatric settings. The consensus statements
generated converged into 4 key themes, which represents a convenient basis for
describing best practice as found in the studies reviewed.
Service users should be more involved in all processes concerning PRN. This
should be individualised, involving joint decision-making, negotiation, and
should whenever possible take account of advance directives and preferences:
None of the articles reviewed had user involvement as its primary focus, although
half of the participants in Baker et al’s (2007b) qualitative study of clinicians’ PRN
medication practices reported that their decision to prescribe or administer PRN was
influenced by patient preferences, and half of the clinicians reported providing some
information about PRN to patients, although the content of this was limited, and it
appeared that patients usually only received additional information if they asked.
Information provision on side effects was particularly scarce, and was often only
given when staff did not want a patient to take a particular medication. In an earlier
qualitative study of service users’ experiences of PRN medication (Baker et al, 2006),
participants reported feeling empowered by being able to decide about the timing and
dose of extra medication, making them feel more in control. However, participants
also reported that the process associated with the use of PRN was confusing and
stigmatising, and expressed anger, frustration and embarrassment at refusals of
medication that they had requested. Such refusal was seen as disempowering,
especially when not accompanied by an explanation from staff, or if they took place
in public ward areas. Some participants also reported not being informed that PRN
medication had been prescribed. In Baker et al (2010) no indication was found in any
of the casenotes of patients who had received PRN medication to the effect that
information had been given to the patient.
Prescribing and administering PRN should be based on assessment, leading to
a clear, proactive indication for use in the prescription. When administered,
PRN should be for the reason it was prescribed. Indications for use therefore
need to be clear and agreed by all: Participants emphasised the importance of
assessment in Baker et al (2007b), although they also reported that haloperidol and
lorazepam were routinely prescribed as PRN without assessment. More specifically,
participants in Usher et al (2009) emphasised that the prescription and administration
of PRN medication should be based upon thorough assessment of the patient, and
thorough knowledge of the patient and background factors.
Lack of clarity of indications for PRN use is also noted among the studies reviewed.
Craven et al (1987) found that no indication for use was specified in 47% of
prescriptions, and when indication for use was not specified 11% of PRN
prescriptions were administered for different reasons on different occasions, and
Walker et al (1991) found that 30% of the patients in their study had a prescription
which did not specify any indication for the drug. In addition to absence of indications
for use in PRN prescriptions, Baker et al (2007a) found that 71% of the clinicians
interviewed had encountered occasions where PRN medication had been used for
reasons other than the prescribed indication for use, and it was also commonly found
10
among the studies reviewed that the reason why PRN medication was administered
was not recorded in casenotes. This is discussed in more detail below. The studies
reviewed also note more general problems with PRN prescriptions than discussed
here. Those concerned with the possibility of PRN medication possibly contributing to
accidental high doses and polypharmacy are also discussed below, but other
problems include lack of a clearly indicated total 24-hour dose (Walker, 1991; Baker
et al, 2010), and generally poorly written (or even illegible) prescriptions (Adamson,
1995; Baker et al, 2007b; Usher et al, 2009).
Prescriptions should be time-limited, thereby encouraging the process of
review, which should include evaluation of the effectiveness and treatments
and take into account service users' experience of taking PRN: It was also
commonly reported among the studies reviewed that PRN medication prescriptions
were not time-limited, or were not subjected to regular review. Mason & Dewolfe
(1974) found that 36% of antipsychotic PRN prescriptions had been written by a
previous doctor to their current one, and that 89% of PRN prescriptions had been in
place for between one and six months without being re-written, despite the hospital
policy to re-write prescriptions at least once per month. Craven et al (1987) found
that only a quarter of 25% of PRN prescriptions were directly stopped by doctor, with
the remainder being allowed to expire. Participants in Baker et al (2007b) suggested
that the review process for PRN appeared vague, and that reviews that included
PRN were infrequent. A clear trigger for review was when nursing staff identified a
problem - the most commonly cited one being when additional doses of PRN were
needed or if there were concerns that a patient might be an "addict" (especially
benzodiazepines, but also procyclidine). The issue of misuse of PRN medication by
patients is also raised in Usher et al (2009), and is discussed in more depth in
D’Mello et al (2000) and Schaefer et al (2011). The evaluation of the effectiveness of
PRN medication is hampered by lack of reporting and by poor definitions of
effectiveness that are common among the studies reviewed. This issue is discussed
in more detail below.
Staff need to develop knowledge and awareness about potential side effects
prior to using PRN: Problems were also identified in the studies reviewed
concerning staff knowledge and awareness about potential side-effects of PRN, as
well as other safety concerns. Birmingham et al (1999) found that, while nurses
participating in their study of the use of PRN antimuscarinic medication emphasised
the importance of objective assessment for antipsychotic-induced side-effects prior to
administering antimuscarinics, and demonstrated a good working knowledge of acute
extrapyramidal side-effects, many also indicated that they would administer
antimuscarinics for other reasons. For example 42% said that they would give PRN
procyclidine to a patient complaining of a dry mouth, and 36% said they would give it
for blurred vision. Both of these side-effects would have been worsened by
antimuscarinics. Nearly half of the participants said that they would treat tardive
dyskinesia with antimuscarinics, although these would have no value in treating this
side-effect. Usher et al (2010) found that while most responses were in keeping with
accepted guidelines and accepted practice, many answers given by clinicians
responding to clinical vignettes involving PRN use indicated a lack of knowledge of
best practice (including extremely high dosages of benzodiazepines, inappropriate
administration of risperidone in an elderly patient, administration of PRN medication
secreted in food, inconsistent adherence to guidelines, and lack of awareness of
special needs of certain groups). This might be attributable to shortcomings in
training highlighted in an earlier study (Usher et al, 2010), in which participants
reported that their pre-registration training had not provided sufficient information to
assist with the decision-making surrounding PRN, and gave little indication of
opportunities to update knowledge through in-service or formal education.
11
2.3
Clinical decision-making in PRN use.
Baker et al (2007b) reported that decisions to administer PRN medication were often
reported to be based around patient history, mental state, and risk assessment,
although as mentioned above, certain medications appear to be prescribed routinely
for PRN use, irrespective of these considerations. Safety, knowledge of the patient,
and the patient’s level of distress were all mentioned as influential by the participating
clinicians. Nearly all of the participants reported that nurses influenced the
prescribing practices of medical staff (particularly junior doctors), which usually
involved obtaining higher doses of typical antipsychotics, and, on occasions,
prescriptions for Acuphase. In contrast, very few nurses reported that their decisions
to administer PRN were influenced by medical staff. Baker et al also report an
impression that a particular sub-group of nurses (termed “the old school”, which were
often, but not exclusively, night staff) who administered PRN more frequently, as did
those who had experienced adverse events (e.g. assault) or who frequently secluded
patients. Decision-making was also highlighted in Usher et al (2009), where the
patient’s level of distress, agitation, aggression, and psychosis, concern for the safety
of the patient or for others in the environment, and patients’ requests were cited as
influencing the decision to administer PRN medication. Most of the participants also
emphasised that PRN medication should only be administered when other
alternatives had been tried and found unhelpful. This topic featured in several of the
studies reviewed, and is discussed more fully below. Participants also made
suggestions for improving practice, which mainly concerned improving the clarity,
adequacy, and accuracy of prescriptions, access to up-to-date information, and
emphasising the importance of awareness of safety of patients and others in the
ward environment.
Usher et al (2009) also report environmental factors that influenced decision-making,
including the mental state of other patients on the ward, (especially if these included
numerous psychotic or agitated patients), staffing levels (being short-staffed was
given as a reason for high levels of PRN use), and the use of casual staff who were
less likely to be familiar with the patients. The more contextual factors affecting
clinical decision-making in PRN use were explored by Sonntag et al (2006) in their
study of the use of sedative drugs in nursing homes for older patients. They found
that 54% of the probability of the administration of PRN sedatives depends on
institutional characteristics such as low perceived competence of the staff, high ratio
of unqualified staff to residents, and increased average level of patient disturbance
on the ward. Furthermore, when these factors were entered into the model, 32% of
the variance remained, suggesting that a substantial number of unidentified
institutional characteristics were also exerting an effect.
Baker et al (2008b) attempted to improve upon clinical practice by means of an
intervention study which used a good practice manual based upon previous research
and guidelines (Medical Research Council, 2000; Baker et al 2006; Baker et al
2007a, 2007b; Baker et al, 2008a). The following themes were included in the
manual:
1.
2.
3.
4.
5.
6.
7.
Considering the patient (knowledge, preferences and choices).
Improving prescription quality.
PRN as part of the clinical management plan.
Evaluating the effects and side-effects of PRN.
Frequent review of PRN.
Enhanced documentation by the multidisciplinary team.
Preventing distress when using PRN.
12
8. PRN as a last resort encouraging the use of non-pharmacological
interventions.
9. Additional training and education is required for all staff.
Data on PRN use on two acute inpatient wards were collected for a four-week period.
This was followed by a two-week period to allow staff to become familiar with and to
incorporate the principles outlined in the manual into their clinical practice, and then
data was then collected for a further four-week period. The manual was favourably
received by the clinical team (with many members of it indicating that it had changed
their clinical practice), the types of drugs administered PRN were found to have
changed significantly (reduced benzodiazepines and antipsychotic use, and
increased use of hypnotics), and provision of information and educating patients
regarding PRN medication also improved significantly. However, the mean quality
score for nursing notes reduced significantly over the study period, nondocumentation of PRN administration increased (although not significantly) and
medication errors (beyond poor prescribing quality) were found in the notes of nearly
two-thirds of the patients.
2.4
Demographic profile of patients
An aim of the review was to establish a profile of patients who were subjected to
PRN psychotropic medication. Particular reference was made to age, gender,
ethnicity and diagnosis, although other variables were also examined.
2.4.1
Age: Age differences between patients who are prescribed and/or have
received PRN psychotropic medication are commonly reported in the
literature, but comparatively few papers report the statistical significance of
them. Benson (1986) found that patients aged 25 to 44 years were
significantly more likely than older patients to be prescribed PRN
psychotropics, and the multivariate model used found that age was the only
significant patient demographic variable, which was negatively associated
with the likelihood of having PRN psychotropics prescribed. This is described
as clinically appropriate, as large doses of psychotropic medication for older
patients is discouraged because they are less tolerant of it and require less to
derive a therapeutic effect. Benson also found that when level of impairment
was taken into consideration, the relationship between patient age and PRN
medication disappeared, indicating that severely symptomatic patients were
likely to receive PRN medication irrespective of age. Another prescription-only
study (Hales & Gudjonsson, 2004) also found that younger age on admission
was significantly associated with PRN psychotropics being prescribed on
admission, which was thought to possibly reflect doctors’ perceptions that
younger patients would be more likely to need PRN medication than older
patients. Again, the actual administration of PRN psychotropics during the
patients’ inpatient stay did not feature in this study. An earlier study of PRN
administration patterns in a Regional Secure Unit (McLaren et al, 1990) found
that patients who received PRN psychotropics were significantly younger than
those who did not (mean age 29.5 years vs. 33.1 years). Possible reasons for
this are not discussed. Winterfield et al (2009) studied both prescription and
administration of PRN psychotropics in a child and adolescent psychiatric
service, and found that while older patients were significantly more likely to be
prescribed PRN psychotropics, there was no significant age difference
between those who actually received them and those who did not. Again,
possible reasons for the age difference in relation to prescribing are not
explored, but the lack of age difference for PRN administration was though to
13
be due to the interactions between patients and staff, and staff variables such
as age, gender, and staff training which were not considered in the study.
Two other studies reviewed found younger age to be significant. Geffen et al
(2002) found that, while age was not associated with the administration of
PRN antipsychotics, younger patients received significantly higher doses,
while Philip et al (2008) report that patients receiving PRN quetiapine were
slightly (but significantly) younger (mean age 39 vs. 40 years). Neither study
discusses possible explanations for this finding.
In contrast, Craven et al (1987) found that being aged 50 or over was
significantly associated with the rate of both PRN psychotropic prescription
and administration in general, and with the rate of prescription and
administration of PRN sedative-hypnotics The authors consider that this may
be because of a higher frequency of night-time insomnia among older
patients, or because older patients are not considered by clinicians to be
amenable to non-pharmacological interventions for insomnia. This finding is
partially mirrored by O’Reilly & Rusnak (1990), who report that patients
receiving PRN sedative-hypnotics were significantly older than those who did
not (mean age 37.9 years vs. 25.1 years). While acknowledging this
increased use of hypnotics among elderly patients, the authors point out that
none of the geriatric patients in the study were given hypnotics, and that
hospital policy strictly regulated the use of such drugs. However, no
explanation of the age-related finding among the non-geriatric patients is
offered.
Where significant differences are reported, findings regarding the relationship
between age and PRN psychotropic medication are mixed.
2.4.2
Gender: Only two of the studies reviewed found any significant relationship
between gender and PRN psychotropic medication. While Geffen et al (2002)
found no gender-related differences in frequency of PRN administration, male
patients did receive higher daily doses of PRN antipsychotics, and Winterfield
et al (2009) report that while female child and adolescent psychiatric patients
were more likely to have PRN prescribed (51% of female patients vs. 21% of
male), no significant gender difference was found between patients
administered PRN psychotropics and those not. Once again, Geffen et al do
not discuss possible reasons for this finding, while Winterfield et al again
attribute it to interactions between patients and staff, and staff variables such
as age, gender, and staff training.
Where significant gender differences are reported, gender does not appear to
have a relationship with the administration of PRN psychotropics as such,
although adolescent female patients seem to be more likely than adolescent
males to be prescribed them, and adult male patients receive higher daily
doses.
2.4.3
Ethnicity: Three of the reviewed studies reported significant differences
concerning PRN psychotropic medication and ethnicity. Flaherty & Meacher
(1980) found that they were more frequently administered to Black patients
than to White patients, possibly because of a stereotypical view of Black
patients as dangerous leading to the use of more restrictive containment
methods. The Black patients were not thought to be in fact larger or stronger
than the White patients, so this was not in itself thought to be a reason for the
observed higher frequency of PRN administration. Benson (1986) reports that
14
non-White patients with a high level of psychiatric impairment were
significantly more likely to be prescribed PRN psychotropics which he notes
as consistent with earlier findings. However, because dangerousness itself
was no assessed in the study, it was impossible to ascertain whether Black,
highly impaired patients did in fact present a higher level of risk than highlyimpaired White patients, although Benson does suggest that racial
stereotypes influence (typically White) psychiatrists’ views that this patient
group is particularly problematic and in need of additional medication. This
view is also found in Usher et al (2009), in which medical and nursing staff
identified being a young, male, and indigenous Australian as a predictor of
being administered PRN medication. Usher et al suggest that this could be
due to the manner in which the behaviour of indigenous Australian men is
interpreted by clinicians, a failure to engage such patients in meaningful
treatment discussions, and/or due to a higher level of acuity on admission
found among such patients. Whatever the reason, cultural identity was seen
as a clear influence on the decision to use PRN psychotropics, and this bias
was noted as consistent with previous research which suggests that AngloEuropean and White North American clinicians are more likely to interpret as
threatening or aggressive when it is displayed by non-White patients. Bernard
& Littlejohn (2000) also report that significantly more non-White patients
received PRN psychotropics than White patients in an adolescent unit, and
that, of all individual ethnic groups, African-Caribbean patients were most
likely to be prescribed them. However, while noting that this is an issue of
interest and concern, the authors consider that their sample was too small to
draw clear conclusions from. Interestingly, Hales & Gudjonsson (2004) who
specifically examined the issue of ethnic differences in the use of PRN
medication found no such relationship.
Black patients appear to be significantly more likely to receive PRN
psychotropics than White patients, which may be because racial stereotypes
influence psychiatrists’ views that this group of patients is particularly
problematic and therefore needs additional medication, but could also be due
to a higher level of acute symptoms on admission in Black patients.
2.4.4
Interactions between age and gender: Swart et al (2011) report the only
significant interaction effect between variables found in all the studies
reviewed. They found that among patients who received PRN psychotropics,
younger male patients were significantly more likely to have received PRN
than female patients, while older female patients were more likely to have
received PRN than male patients.
2.4.5
Marital status: Only one study (Benson, 1986), reported significant findings
concerning the relationship between PRN psychotropic medication and
marital status. Although he found that unmarried patients were significantly
more likely to receive PRN psychotropics than married patients, possible
reasons for this association are not discussed.
2.4.6
Employment status/education: None of the studies reviewed investigated
or commented upon any relationship between PRN medication use and
employment status. The only study which mentioned any relationship
between PRN use and education level was by Evans & Di Scipio (1980), who
found that academic achievement did not distinguish between adolescent
inpatients who received high (but unspecified) numbers of PRN
administrations and those who did not.
15
2.4.7
Other sociodemographic variables and PRN use: None of the studies
reviewed mentioned any relationship between PRN psychotropic medication
and the patient sociodemographic variables of religion, country of origin,
accommodation, or living arrangements, nor made any reference to PRN
psychotropics with regard to patients’ family or family life.
2.4.8
Diagnosis: Just over half of the papers reviewed which reported significant
associations between PRN psychotropic prescribing and administration and
diagnosis were conducted in child and adolescent settings. Three out of the
five papers concerning research in these settings found that developmental
disorders were significantly associated with PRN use. Vitiello et al (1987)
found that psychiatric diagnosis as such did not predict number of PRN
administrations, but patients with moderate learning disability received
significantly more PRN administrations than patients with no learning
disability, mild LD and severe LD. They also found that 70% of PRN doses
were in response to aggression and disruptive behaviour, and while this might
account for why patients affected by more severe learning disability received
fewer doses (these patients are described as more passive and dependent,
and therefore less disruptive), no explanations are discussed concerning why
less PRN medication was administered to the patients with mild learning
disability. Dean et al (2006) also reported that significantly more doses of
PRN were administered to patients with pervasive developmental disorder,
ADHD, and mental retardation, as well as patients with a greater number of
comorbid diagnoses, and consider that this might be because PRN is utilised
in more complex patients where impulsive behaviour is a feature. Echoing
this, Swart et al (2011) found that children with DSM Axis II intellectual
disabilities, besides receiving significantly more PRN than patients diagnosed
with Axis I mental disorders, were more likely to receive PRN in response to
risk of self-injury or space issues, and having received one PRN dose, were
more likely to receive future doses than patients with Axis I disorders. This
was attributed as due to the impairment of learning potential and executive
function in people with developmental disabilities. Winterfield et al (2009)
report that very few patients with learning disorders (undefined in the paper,
but different to learning disability) received PRN medication, but since almost
half of these patients were treated in the partial hospitalisation facility
(essentially a day unit), they were therefore less likely to be disruptive than
the inpatients.
Regarding adult patients, participants in Usher et al (2009) identified patients
who displayed signs of aggression/agitation, or had either a psychotic
disorder or elated mood as more likely to receive PRN medication, which was
largely echoed in the quantitative papers that were reviewed. For example,
Benson (1986) found that patients with schizophrenia and with chronic mental
disorders were significantly more likely to be prescribed PRN, while patients
with low to mild levels of psychiatric impairment were less likely to be
prescribed PRN, and were prescribed significantly lower doses. Craven et al
(1987) found rather different associations between PRN prescription and
diagnosis, in that a diagnosis of personality disorder was significantly
associated with rates of PRN prescription and administration, and with rates
of prescription and administration of PRN neuroleptics and sedativehypnotics. PRN neuroleptic medication was also found to be significantly
associated with mania, as was the rate of PRN administration in general. The
prescription of PRN antiparkinsonian medication was significantly associated
with schizophrenia, mania and personality disorder (probably reflecting
prescribing practices in line with the association of PRN neuroleptic
16
prescriptions for these diagnoses). Geffen et al (2002) reported that patients
with mania/mixed affective psychosis and schizophrenia-related disorders
received significantly higher PRN doses than patients with depression, and
that patients with mania/mixed affective psychosis received significantly
higher doses of PRN benzodiazepines than patients with schizophrenia. In
contrast, Walker (1991) found no significant relationship between PRN
administration in general and diagnosis, although he found that manic
patients and patients with schizophrenia less likely to receive PRN hypnotics
than patients with major depression. While patients with anxiety symptoms
were significantly more likely to receive PRN anxiolytics, patients with
psychotic symptoms were as likely to receive anxiolytics as antipsychotics,
which may reflect Walker’s finding that anxiolytics were more likely to be
judged effective in alleviating patient distress, and the fact that improvement
can be achieved more safely with anxiolytics because they have a more
benign adverse effect profile than antipsychotics. With specific regard to PRN
quetiapine, Philip et al (2008) found that only 17.4% of patients receiving it
had indicated diagnoses (schizophrenia and bipolar affective disorder), and
concluded that it was being used as a treatment for agitation when clinicians
were reluctant to use benzodiazepines or conventional antipsychotics.
Among child and adolescent inpatients. PRN psychotropic use appears to be
associated with developmental disorders rather than DSM Axis II mental
disorders. In adults, most of the studies reviewed which examined psychiatric
diagnosis and PRN use found it to be associated with psychotic disorders
(particularly schizophrenia), mania, and personality disorders, which probably
reflects the use of PRN medication in containing impulsive, erratic, and
possibly dangerous behaviour.
2.4.9
Admission status: Curtis et al (2007) was the only paper reviewed which
reported a significant finding concerning the legal status of inpatients
receiving PRN psychotropics. They found that all the patients who received
more than 10 PRN administrations during the study period were detained
patients, and that mean number of PRN administrations in detained patients
was more than double than that of informal patients. This finding was
statistically significant, and suggests an association.between formally
detained patients and PRN medication use. However, Craven et al (1987)
found no significant relationship between admission status and ether the rate
of prescription or rate of administration of PRN psychotropics.
2.4.10 Length of inpatient stay: Five of the papers reviewed report significant
relationships between PRN psychotropic use and length of inpatient stay, four
of which are studies undertaken in child and adolescent units. Bernard &
Littlejohn (2000), Dean et al (2006), Winterfield et al (2009), and Swart et al
(2011) all report that PRN use and length of inpatient stay are positively
related. Winterfield et al additionally report that female patients were more
likely to receive PRN medication for the first time later in their admission than
male patients, and that children with developmental disabilities tended to
receive PRN for the first time earlier in their admission than children with Axis
I diagnoses. However, Swart et al found that, on the same age level, female
patients had 15% higher odds to receive their first PRN medication earlier
than male patients, and Vitiello et al (1987) found that the number of PRN
administrations did not correlate with length of stay. In their study of the use
of PRN sedative-hypnotic medication in a general hospital setting, O’Reilly
and Rusnak (1990) found no correlation between length of stay and PRN
administration among the adult psychiatric patients. Bernard & Littlejohn
17
attribute the fact that admissions involving PRN medication were significantly
longer than those with no PRN use to the nature and severity of problems
leading to admission. However, direct measures of the severity of
psychopathology were not used in the study, which is a weakness of many of
the studies reviewed. They also report that significantly more PRN
psychotropics were administered in the first quarter of the admission, which
supports the idea that PRN is used as a response to agitated, aggressive and
impulsive behaviour, as this is more likely to be seen early in the admission
before treatment has started to become effective. Several other studies in
adult inpatient settings also report more frequent PRN use early in the
admission, although the rates of use vary widely. Fishel et al (1994) report the
statistically significant finding that nearly 78% of PRN medication was
administered in the first four days of admission, but do not discuss possible
reasons for this. Gray et al (1996) found that just over 38% of PRN was
administered in the first four days of admission, and frequency of PRN use
decreased throughout the course of the admission, and Usher et al (2001)
found that PRN was more likely to be administered on the first and second
day of admission, with a reduction in likelihood of administration after day
nine. Similarly, Curtis & Capp (2003) reported that most common day for the
initial administration of PRN was the day of admission, and while they report a
‘significant’ decrease from the second day, no statistical significance level is
reported. Chaichan (2008) found that over half of the mean total number of
PRN administrations were given in the first three days after admission, with
the rest being administered throughout the remainder of it, and over half of
the mean total chlorpromazine equivalent of PRN medication received was
also administered in this period. Unfortunately, none of these three studies
report significance levels for their findings.
Most PRN psychotropics use usually occurs in the early stages of admission,
and becomes less frequent throughout the admission’s duration.
2.4.11 Previous admissions: Only one study reviewed, Craven et al (1987),
commented upon the possible relationship between number of previous
admissions and psychotropic PRN use. The number of previous admissions
was found not to affect the rate of PRN administration in general, but it was
significantly associated with the rate of administration of PRN
antiparkinsonian medication. This was thought to be because nurses
recognise or anticipate early signs of parkinsonian side-effects in patients that
they knew from previous admissions who had received neuroleptic
medication, or because the patients who had experienced these symptoms in
previous admissions might recognise them more readily, and ask for PRN
antiparkinsonian medication.
2.4.12 Chronic physical illness or disability: None of the studies reviewed
commented upon any relationship between PRN psychotropic use and
patients with chronic physical illnesses or disabilities.
2.5
Characteristics of patients receiving repeated PRN doses
As mentioned above when discussing rates of PRN use, many patients receive more
than one dose of PRN medication. In the studies reviewed it was commonly reported
that a relatively small proportion of the patients received a large proportion of the
PRN mediation that was administered. The proportion of high-PRN patients varies
from study to study, and different studies define high PRN use differently and have
study periods of differing duration. None of the studies reviewed reported the
18
statistical significance of observed proportions of patients receiving high levels of
PRN medication compared to those who did not.
Baker et al (2008) report that of the 35 patients who received PRN medication, 11%
received 50 or more PRN administrations in the 10-week study period. Thapa et al
(2003) found that the 14% of patients who had received PRN medication over a
three-month period accounted for 54% of the PRN doses administered. In Curtis et al
(2007), nearly a quarter of patients who received PRN medication over a one-month
period received 10 or more administrations during the month, and collectively
accounted for just over 46% of PRN administered. Stein-Parbury et al (2008) found
that less than 3% of patients in their study received 40 or more PRN doses during
their admission. These patients had diagnoses of schizophrenia (39%),
schizoaffective disorder (33%) and bipolar affective disorder (28%). Another study
finding a link between a small group of patients receiving repeated PRN doses and
psychosis is McLaren et al (1990). While no overall relationship between diagnosis
and PRN use was observed, four patients out of the 12 with a diagnosis of
schizophrenia accounted for 52% of PRN administrations. Craig & Bracken (1995)
also found that schizophrenia was the predominant diagnosis among the 27 patients
(2.8% of the hospital population) who accounted for 44.4% of unscheduled
medication (PRN and stat doses) administered in a one-month study period. These
patients received an average of 9.7 doses of PRN each, 59% of them had a
diagnosis of schizophrenia, 59% were aged over 40 years, and 52% were men.
The disproportionate amount of PRN use found among a relatively small group of
patients is also reported in child and adolescent psychiatry, as is a relationship with
aggressive behaviour and psychosis. Vitiello et al (1987) found that 18% of inpatients
who received PRN psychotropics had received over 50 PRN doses each. While the
actual number of doses that this group of patients received is not given, even if a
figure of only 50 PRN doses each is assumed, this still accounts for 27.7% of PRN
doses administered in the one-year study period. Bernard & Littlejohn (2000) found
that PRN psychotropics were administered more than 10 times in 11% of admissions,
accounting for 60% of PRN doses administered. While psychiatric diagnosis was not
recorded in this study, the authors believe that this group of patients who received
high levels of PRN medication was characterised by histories of extremely antisocial
and aggressive behaviour prior to and during their admissions. This echoes Evans &
Di Scipio’s (1980) finding that the 10 patients who had received the most PRN
administrations (number unspecified) were characterised by pre- and post-admission
histories of violence and a diagnosis of a psychotic disorder.
2.6
Relationship of PRN to regular medication
PRN medication is frequently prescribed alongside regular medication during
inpatient admissions. Craven et al (1987) found that 97% of PRN prescriptions were
in addition to prescriptions of regular psychotropic medication. More recently, Geffen
et al (2002) reported that, when regular and PRN medications were combined, 76%
of admissions involved prescription of two or more antipsychotics and 38% two or
more benzodiazepines. Concomitant PRN medications accounted for 31% of the
total antipsychotic dose and 28% of the total benzodiazepine dose in patients who
received them by schedule. High rates of prescription and administration of regular
and PRN psychotropics are also reported in child and adolescent psychiatry. Vitiello
et al (1987) found that the number of PRN administrations was significantly
correlated with dose of regular neuroleptics. In Kaplan & Busner (1997), high
proportions of patients in three different child psychiatric hospitals settings who were
on regular antipsychotics also received PRN or stat doses of antipsychotics (although
no statistically significant differences were found between the state, private, or
19
county-university hospitals). Winterfield et al (2009) found that 67% of patients who
were prescribed PRN medication were already receiving regular psychotropics. In
relation to the risk of PRN medication and polypharmacy among child and adolescent
inpatients, Dean et al (2006) report that patients receiving a larger number of
concomitant medications at admission were significantly more likely to be prescribed
PRN, and that patients receiving polypharmacy received a significantly greater
number of PRN doses, while Russell et al (2006) found that PRN medication
increased the risk of polypharmacy among child and adolescent inpatients.
Thapa et al (2003) comment that PRN medication may expose psychiatric inpatients
to unnecessary psychotropic medications, and that, given the potency of these
agents, this can increase the risk of significant side-effects (Ayd, Jr, 1985). Because
PRN psychotropics are typically prescribed as an adjunct to regular psychotropic
medication, if they are administered there is a risk of causing morbidity through
contributing to a high (and potentially toxic) dose. Another risk is that when combined
with regular medication, PRN medication might cause harmful pharmacokinetic drug
interactions and other adverse effects through polypharmacy.
Milton et al (1998) examined changes in antipsychotic prescribing in two surveys of
psychiatric inpatients conducted eight and 32 months after the publication of a Royal
College of Psychiatrists’ Consensus statement on the prescribing of high-dose
antipsychotics (Thompson, 1994). This states that only fully-qualified psychiatrists
(MRCPsych) should recommend the prescribing of antipsychotic medication above
British National Formulary advisory limits. They found that when PRN prescribing
(usually by junior doctors) is included with regular prescriptions, mean potential
doses and the numbers of patients who might receive high doses increases
substantially. While both the mean chlorpromazine equivalent doses and the
proportion of patients receiving high-dose antipsychotics (including PRN) fell
between the two surveys (from 1,359mg/day to 1,138mg/day, and from 47% of
patients to 39%), the statistical significance of these reductions is not reported. While
the actual administration of prescribed PRN was uncommon (4% to 5% of
prescriptions, suggesting that injudicious prescribing is less clinically relevant than
supposed), the potential still exists for unwittingly-administered high doses. Another
audit by Bowden (1999) also found that PRN medication prescriptions were a
significant source of potential high dosage, although only one patient out of a
potential eight actually received PRN medication leading to exceeding the maximum
dose, while one other patient reached the maximum dose. While the Consensus
Statement recommends that ideally the same drug should be prescribed for regular
and for PRN doses, that only one antipsychotic drug should be prescribed PRN, and
that PRN medication should be prescribed at a specific rather than a ranged dose,
Bowden reports that only 42% of patients with a regular antipsychotic and a PRN
antipsychotic prescription were prescribed the same drug, five patients were
prescribed two PRN drugs (and one was prescribed three), and 80% of antipsychotic
PRN prescriptions gave ranged doses. A number of measures were implemented to
improve prescribing, and on re-audit six months later both the number of
prescriptions for a ranged dose of PRN and the number of prescriptions for different
regular and PRN drugs had fallen significantly. While the number of patients
prescribed more than one PRN drug had fallen from 10% to 2%, this was not found
to be significant, probably because of the small number of patients concerned.
Both Milton et al (1998) and Bowden (1999) report studies of geographicallyrestricted services which may not be readily and more widely generalisable. Paton et
al (2008) invited all NHS trusts and private healthcare providers in the UK that
provide specialist mental health services to participate in a quality-improvement
project focussing upon high-dose and combination (more than one drug prescribed)
20
antipsychotic prescribing in acute wards. In total, 32 services participated, submitting
data on 3,942 patients at baseline and 3,271 patients at re-audit one year later. Little
change was found in the prevalence of high-dose prescribing (36% at baseline, 34%
at re-audit) or combined prescribing (43% at baseline, 39% at re-audit), with PRN
prescribing being the principal cause of both high-dose and combined antipsychotic
prescribing at both timepoints.
In terms of the risk of morbidity due to high dosage from combined PRN and regular
medication doses, Geffen et al (2002) found that both receipt of PRN medication and
greater frequency of PRN administration were significantly associated with morbidity,
which was also significantly associated with the receipt of both PRN antipsychotics
and benzodiazepines. The contribution made by PRN antipsychotics to medicationrelated morbidity is highlighted in this study, as the mean daily dose of haloperidol
observed represented a substantial contribution to the total daily antipsychotic dose.
While extra-pyramidal symptoms were the most frequently recorded type of
medication morbidity (which was also significantly related to PRN administration), a
relatively low rate of such symptoms were observed (15%). This is probably because
the methodology employed (retrospective casenote review) underestimated the true
prevalence (compared to active screening for such symptoms).
Davies et al (2007) examined the risk potential of PRN medication causing
dangerous pharmacokinetic drug reactions when administered alongside regular
medication. Prescription-chart data were collected from 323 psychiatric inpatients in
a British city in order to establish the prevalence of PRN prescription and
administration, and to assess the potential for interactions involving CYP2D6 and
CYP3A4 between drugs prescribed and administered. CYP2D6 and CYP3A4 are the
most important CYP enzymes involved in psychotropic drug elimination (Pollock,
1994), metabolising many psychotropic drugs that are prescribed for both regular and
PRN administration. Because several drugs are potent inhibitors of CYP activity, the
slowing of metabolism that they cause increases plasma concentrations and
increased adverse effects (Vandel et al, 1995). Overall, 117 combinations of drugs
were found that could give rise to clinically active CYP2D6 or CYP3A4 interactions.
Of these, 84 combinations involved drugs prescribed for PRN administration, and 66
patients (20%) had at least one potentially clinically important CYP2D6 or CYP3A4
combination which involved one or more PRN drugs.
2.7
Temporal ecology of PRN administration
Significant findings concerning days of the week or time of day at which peak PRN
use is observed might suggest changes to working practices that might reduce the
need for PRN medication. However, statistically significant findings on this subject
are the exception among the papers reviewed.
2.7.1
Time of day: Broadly speaking, the consensus among the reviewed papers
in terms of peak time of day for PRN administration is mid-afternoon to nighttime. This has been explained in terms of night-time insomnia and anxiety,
and disturbed sleep as a feature of mental disorders (Usher et al, 2001; SteinParbury et al, 2008; Craven et al, 1987; Winterfield et al, 2009) lower staffing
levels, either because fewer staff work on the night shift or because staff are
busy and unavailable due to shift handovers (Curtis et al, 2007; Baker et al,
2010; Winterfield et al, 2009), ‘sundowning’ in elderly patients with dementia
(Baker et al, 2010), and noncompliance with bedtime rules in child and
adolescent patients (Winterfield et al, 2009). Peak times were also observed
in the mornings by Evans & Di Scipio (1980) and Curtis & Kapp (2003), who
ascribe it to the relative non-availability of staff because this is a busy time, or
21
because of anxiety brought about by the doctors’ appointments which were
held at this time.
2.7.2
Day of week: Variations in PRN administration throughout the week have
also been observed, with peaks being reported on Monday, Tuesday,
Thursday, Friday and at the weekends, and troughs being reported on
Monday, Friday, and weekends. Possible reasons for observed peaks (where
they are made) include anxiety about the outcomes of magistrates cases
(held on Thursdays) (Usher et al, 2001), and fewer staff on duty meaning that
PRN medication is relied upon more, and possibly more admissions (Fishel et
al, 2004). The trough in PRN use that Fishel et al (2004) also report is
consistent with their hypothesis that possible increases in admissions over
the weekend result in more PRN use, because most PRN was found to be
administered very early in the admission. However, troughs were also
observed on Fridays and at weekends in Smith et al (2008) and Usher et al
(2001). Usher et al propose that the weekend trough might be because there
are fewer visits by relatives and appearances by consultants (both of which
might provoke anxiety), and because staff are less busy and therefore have
more time to spend therapeutically with patients.
2.7.3
Month: Finally, an interesting aspect of temporal distribution of PRN use is
reported by Vitiello et al (1987) who found a significant difference in the
distribution of PRN medication throughout the year, with the maximum being
in March, and the minimum in December. As this was a study of a child
psychiatric unit, the trough in December was attributed to the possible
influence of Christmas, which may make patients more compliant or staff
more tolerant towards disruptive behaviour.
2.8
Antecedents of PRN use
Several difficulties appear when attempting to discover the antecedents of PRN use.
Firstly, antecedents frequently go unreported when PRN is administered. While this
is an interesting finding in itself, it means that there is uncertainty about the true
prevalence of the different antecedents which are reported. Secondly, there is usually
a lack of precision about the definitions of the antecedents, and indeed, apparently
similar verbal labels can be given to different antecedents. For example, Curtis &
Capp (2003) report agitation and restlessness as different antecedents, but as they
are not specifically defined, it is hard to tell how they were differentiated in practice.
Agitation and restlessness are also reported in Usher et al (2001) and again, they are
not differentiated. Mason & Dewolfe (1978) report agitation and overactivity. Studies
also use combined categories of antecedents, making comparison across studies
even more problematic. Philip et al (2008) use a category they call ‘agitation/anxiety’,
as well as agitation and anxiety as separate antecedents. Dean et al (2009) have a
combined category ‘insomnia/agitation’, as well as agitation and insomnia. Curtis et
al (2007) combine this problem with that of possible duplication and redundancy
mentioned previously with their categories of ‘agitation/anger/aggression’, ‘elevated/
upset/anxious’ and ‘irritable/unsettled/ restless’. Vitiello et al (1987) refer to
‘disruption on the ward’, a combination of fighting and unco-operativeness. Another
problem is a lack of detail in reporting. Three studies report patients requesting PRN
medication as the antecedent for its administration, and one of them also reports
PRN medication being administered at the doctor’s instruction, but the complaint for
which PRN medication is requested is not noted. Two of these studies are
retrospective casenote audits, and this lack of detail is an example of one of the
problems with this methodology. Finally, because there is usually no rating of the
severity of the behaviour or symptom for which PRN medication is administered, it is
22
uncertain how appropriate the intervention might have been. The one exception to
this among the studies reviewed is Chaichan (2008), who reports on the use of the
Excited Component of the Positive and Negative Symptom Scale (PANSS-EC) as a
criterion for the administration of PRN medication to agitated patients. Overall, there
was no significant difference in mean number of doses of PRN medication for
agitation between the patients who were screened on admission with PANSS-EC
and those who were not, but significantly more PRN medication was administered in
the first three days of their admission to those who had been screened, who also had
significantly fewer episodes of aggression during their inpatient stay. While Chaichan
cautions that these findings require further testing, it was concluded that screening
led to a more favourable clinical outcome. Lack of reporting of significance levels for
observed differences between different antecedents and between the same
antecedents at different study sites, or before and after interventions is a more
general problem that was encountered in the review, and must be added to the more
specific problems discussed above.
Lack of reporting antecedents of PRN administration was noted in 11 of the papers
reviewed. The rates for non-reporting of antecedents range from one percent
(O'Reilly & Rusnak, 1990) to 43% (Curtis et al, 2007), with a median reported value
of 14% (O'Brien, & Cole, 2004). See Table 1 for a summary of this finding in the
studies reviewed. The most commonly reported antecedent for PRN administration
was agitation, being mentioned in 21 of the studies reviewed. This was followed by
insomnia, reported as an antecedent of PRN administration in 11 studies. Agitation
and insomnia also feature in compound classifications of reasons for PRN
administration in some studies (i.e. agitation/anger/aggression, agitation/anxiety, and
insomnia/agitation). Agitation was also the most frequently reported indication for
PRN medication, accounting for an average of 49.16% of PRN administrations
across the 21 studies reporting it, while insomnia accounted for an average of 22.4%
of PRN administrations across the 11 studies which report it. Verbal and physical
aggression and deliberate self-harm were comparatively rarely reported as
antecedents of PRN use. PRN was reported as used to prevent likely physical
aggression in four studies (accounting for an average of 27.13% of PRN
administered in them), to contain actual physical aggression in five studies
(accounting for an average of 13.62% of PRN administered in them), to contain
verbal aggression in two studies (accounting for an average of 10.75% of PRN
administered in them), and in response to deliberate self-harm in two studies
(accounting for 6% of PRN administered in them. Similarly, PRN medication was
rarely reported as being administered to alleviate psychiatric symptoms. Psychotic
symptoms and anxiety were each reported as antecedents of PRN administration in
four studies (with psychotic symptoms accounting for 9.33% of PRN administration
and anxiety accounting for 10.28%), and panic was cited as an antecedent in one
study (accounting for one percent of PRN administered). Antecedents mentioned in
the studies reviewed and the proportion of PRN administrations that they account for
are presented below in Table 3.
23
Table 3.
Antecedents and non-reporting of antecedents in studies
reviewed.
Antecedent
Study/studies
Antecedents.not reported
Mason & Dewolfe (1974)
O’Reilly & Rusnak (1994)
Fishel et al (1994)
Craven et al (1997)
Usher et al (2001)
Geffen et al (2002)
Curtis & Capp (2003)
O’Brien & Cole (2004)
Dean et al (2006)
Curtis et al (2007)
Stein-Parbury et al (2008)
Mason & Dewolfe (1974)
O’Reilly & Rusnak (1990)
Fishel et al (1994)
Craig & Bracken (1995)
Craig & Bracken (1995)
Gray et al (1996)
Kaplan & Busner (1997)
Kaplan & Busner (1997)
Kaplan & Busner (1997)
Geffen et al (2002)
Curtis & Capp (2003)
O’Brien & Cole (2004)
Dean et al (2006)
Baker et al (2008)
Stein-Parbury et al (2008)
Philip et al (2008)
Smith et al (2008)
Dean et al (2009)
Dean et al (2009)
Baker et al (2010)
McLaren et al (1990)
Stein-Parbury et al (2008)
Geffen et al (2002)
Curtis & Capp (2003)
Curtis et al (2007)
Smith et al (2008)
O’Reilly & Rusnak (1990)
Fishel et al (1994)
Geffen et al (2002)
Curtis & Capp (2003)
Curtis et al (2007)
Agitation
Verbal aggression
Psychotic symptoms
Insomnia
% of PRN
administrations
11%
1%
13%
9%
36.6%
41%
9%
14%
32.3%
43%
36.8%
64%
4%
38%
61%1
57%2
11.9%
100%3
93%4
91%5
49%
19%
23%
38.7%
71.5%
17.9%
75%
60%
38.7%6
29.6%7
77%
9%
12.5%
15%
10%
12%
0.3%
89%
33%
17%
10%
10%
Average
%
18.7%
51%
10.75%
9.33%
1
Intermittent PRN patients.
Discrete PRN patients.
3
Combined PRN and stat doses in a private hospital.
4
Combined PRN and stat doses in a state hospital.
5
Combined stat and PRN doses in a county-university hospital.
6
Baseline figure
7
Post-intervention figure.
2
24
Anxiety
Panic
Likely physical aggression
Overactivity
Disruption on the ward
Physical aggression
Insomnia/agitation
At patient’s request
Medication side effects
Deliberate self-harm
Restlessness
Agitation/anger/aggression
Elevated/upset/anxious
Irritable/unsettled/restless
Alcohol withdrawal
Nightmares
At doctor’s instruction
Relief of patient’s distress
Relieve distress to other
patients
Philip et al (2008)
Smith et al (2008)
Goedhard et al (2007)
Goedhard et al (2007)
Dean et al (2009)
O’Reilly & Rusnak (1990)
Philip et al (2008)
Smith et al (2008)
O’Reilly & Rusnak (1990)
McLaren et al (1990)
Craig & Bracken (1995)
Swart et al (2011)
Mason & Dewolfe (1978)
Vitiello et al (1987)
McLaren et al (1990)
Craig & Bracken (1995)
Dean et al (2006)
Dean et al (2009)
Dean et al (2009)
Dean et al (2009)
Gray et al (1996)
Curtis et al (2007)
Goedhard et al (2007)
Goedhard et al (2007)
Gray et al (1996)
Craig & Bracken (1995)
Curtis et al (2007)
Curtis & Capp (2003)
Goedhard et al (2007)
Curtis et al (2007)
Curtis et al (2007)
Curtis et al (2007)
Curtis et al (2007)
Curtis et al (2007)
Curtis et al (2007)
McLaren et al (1990)
Goedhard et al (2007)
Goedhard et al (2007)
McLaren et al (1990)
9%
7%
17.3%8
13.7%9
15.5%
4%
8%
16%
1%
25%
10%
63.5%
45%
70%
24%
< 10%
14.5%
14%10
5.6%11
4.2%
19.8%
5%
16.6%12
53%13
11%
< 10%
2%
6%
13.1%14
13%
6%
5%
4%
1%
<1%
33%
36.6%15
16.6%16
1%
22.15%
9.33%
1%
32.83%
45%
70%
<13.62%
4.2%
23.6%
11%
<6%
9.55%
13%
6%
5%
4%
1%
<1%
28.73%
1%
Besides these empirical ward-based studies, there have also been qualitative studies
of staff attitudes, knowledge and practice which examine the circumstances leading
up to the administration of PRN medication, which largely confirm the empirical
findings while identifying other factors that affect its use. Geffen et al (2002) found
8
Aggressive patients.
Non-aggressive patients.
10
Baseline figure.
11
Post-intervention figure.
12
Aggressive patients.
13
Non-aggressive patients.
14
Aggressive patients.
15
Aggressive patients.
16
Non-aggressive patients.
9
25
that nurses were significantly more likely than doctors to consider that hallucinations
and delusions, formal thought disorder, and suicidal ideation were appropriate
indications for PRN use, although there was close agreement between doctors and
nurses concerning anxiety and conflict with co-patients as appropriate indications.
Doctors were more likely than nurses (although significance levels are not reported)
to view dysphoria/distress and sleep disturbance as appropriate indications.
Regarding PRN anticholinergics, nurses were significantly more likely to select
inappropriate indications. Doctors were significantly more likely than nurses to view
agitation and sleep disturbance as indications for the administration of PRN
benzodiazepines, and there were high levels of agreement between doctors and
nurses concerning the appropriateness of anxiety, agitation, and sleep disturbance
as appropriate indications for their use. These qualitative findings largely confirm the
antecedents of PRN use identified in the empirical studies, although as we have seen
in the discussion of clinical decision-making in the administration of PRN medication
above, factors other than patients’ symptoms and behaviour which are linked to
individual staff characteristics, staffing levels, and the level of psychopathology
exhibited by other patients on the ward also influence PRN use.
As part of a wider study of medication refusal by patients, Baker et al (2009)
examined the antecedents of two other aspects of PRN use: PRN refusal and
demanding PRN medication. This study is the only one of those surveyed which
mentions these. Refusing PRN medication was found to be related to resistance to
staff demands in other areas, and the ward door being locked. PRN refusal also had
the strongest relationship to overt aggression, and was also associated with drug use
and absconding. It also appeared to be associated with more severe containment
methods. Demanding PRN medication was strongly related to passive resistance
behaviours (such as refusing to eat, refusing to sleep, refusing to see healthcare staff
and refusing to get out of bed), to the ward door being locked, nurse staffing levels,
ancillary community teams, and the use of special observations. There were
additional relationships with drug/alcohol use, and stronger relationships with
absconding and aggression. While this was a large, multi-centre study, its crosssectional design means that the direction of causality cannot be determined, and so
the variables associated with refusing or demanding PRN medication might not be
antecedents, but rather consequences. The statistical modelling strategy used may
also identify some variables as significant purely by chance. Many patient factors
(such as insight, and knowledge of and understanding about medication) which might
bear on medication refusal were not measured. The study was only able to measure
diagnosis as a dichotomous variable (e.g. suffering from schizophrenia or not), while
a more detailed approach might have revealed further associations with medication
refusal.
2.9
Outcomes of PRN use
Fifteen of the studies reviewed reported on the effectiveness of PRN medication, 14
of which were ward-based, empirical studies. As with the antecedents of PRN
administration, eight of the empirical studies noted a lack of reporting of outcomes
(Fishel et al, 1994; Craig & Backen, 1995; Usher et al, 2001; Geffen et al, 2002;
Curtis & Capp, 2003; Curtis et al, 2007; Smith et al, 2008; Stein-Parbury et al, 2008).
Between 2% and 64% of PRN administrations were reported as not recording
outcomes, with a mean rate of approximately 38.13% (this is an approximate figure
because one value was reported as “nearly half”). Seven studies (Craig & Backen,
1995; Usher et al, 2001; Geffen et al, 2002; Curtis & Capp, 2003; Stein-Parbury et al,
2008; Curtis et al, 2007) reported that PRN medication had been ‘effective’, but give
no operational definition of effectiveness. These studies report effectiveness rates of
between 5% and 76%, with a mean of 44.13%. Nine studies (Vitiello et al,1987;
26
Fishel et al, 1994; Craig & Backen, 1995; Usher et al, 2001; Geffen et al, 2002; Curtis
& Capp, 2003; Curtis et al, 2007; Smith et al, 2008; Stein-Parbury et al, 2008) also
reported the proportion of PRN administrations which had been considered
ineffective. These range from 3.7% to 25%, with a mean of 18.73%. Six of the
studies reviewed used operational definitions of PRN effectiveness. Vitiello et al
defined effectiveness as symptom improvement within 90 minutes of administration,
and report that 32% of PRN administrations achieved this standard. McLaren et al’s
(1990) definition was that patients were ‘settled’ by nurses within an hour of receiving
PRN medication, and that significant reductions in conflict behaviours within 30
minutes were observed in incidents where PRN use was precipitated by agitation,
verbal abuse, and threatened or actual violence. However, just over a quarter of PRN
administrations were not effective by this criterion. Walker (1991) defined
effectiveness as symptom relief within two to three hours of administration, and
reported an effectiveness rate of 45%, with anxiolytics being significantly more likely
to be judged effective than antipsychotics. Fishel et al reported ‘favourable’ results
(i.e. notes stated that the patient was “calmed”, or that “good results” or “improved
sleep” were observed following PRN use) in 64% of PRN doses administered in the
state hospital and 30% at the medical centre sites that were studied, and Smith et al
(2008) report that 90% of unscheduled medication doses (i.e. PRN and stat doses)
relieved the symptoms which they were administered to treat. Swart et al (2011)
found that chlorpromazine and lorazepam were significantly more likely to take longer
more than 30 minutes to produce settling effects, while olanzapine was more likely to
produce settling effects in less than 30 minutes. In a qualitative study of clinicians’
knowledge and beliefs concerning PRN medication for psychoses, Geffen et al found
that most of the participating clinicians used subjective and/or objective assessments
of the effectiveness of PRN medication. Over 80% of their participants supported the
effectiveness of PRN conventional antipsychotics for either agitation or psychotic
symptoms, of which chlorpromazine was more likely to be selected as effective. PRN
benzodiazepines were also regarded as effective for agitation, but less so for
psychotic symptoms, and clonazepam and diazepam were the most likely to be
selected as effective. However, 60% of nurses and 30% of doctors preferred to use
PRN antipsychotics for agitation, despite evidence suggesting that benzodiazepines
represent a relatively safe and effective treatment in acute settings. With regard to
the preference for PRN conventional antipsychotics for the treatment of psychotic
symptoms, Geffen et al comment that the short-term response of psychotic
symptoms to PRN benzodiazepines is equivalent to that of PRN antipsychotics, but
are safer, better tolerated, and avoid problems related to psychiatric polypharmacy.
Similarly, Usher et al argue that the contemporary literature supports
benzodiazepines, as the first choice of PRN for agitation and psychotic distress, and
describe the high reliance upon conventional antipsychotics that they found as due to
the lack of sedating effect in unconventional antipsychotics.
An interesting perspective on the effectiveness of PRN medication is given in Evans
& Di Scipio (1980), who estimated that approximately 70% of PRN doses
administered to resistant, agitated adolescent inpatients took effect either
immediately or within a few minutes of administration, which suggests that nonpharmacological factors exert a placebo effect. The administration of PRN
medication under these circumstances is described as a ritualised “termination
strategy”, representing an acceptable way of terminating a stalemated power struggle
that protected both the nurse-patient relationship and the social unit of the ward.
Thought-provoking as this finding is, it is based on retrospective analysis and is
therefore prone to recall biases. Similarly, McLaren et al (1990) report that 7% of the
episodes in which PRN was administered appeared to resolve in less than five
minutes. This suggests that, since a specific medication effect could not have
occurred in that time, this was due to either a placebo effect or a cathartic release of
27
tension during the behavioural crisis, or that the attention of nursing staff enabled the
crisis to be contained. However, McLaren et al also comment that in most cases
where PRN had been judged effective, a genuine pharmacological response had
taken effect.
The effectiveness or otherwise of PRN medication is not the only possible outcome
of its use. There is also the risk of unwanted side effects and harmful consequences.
As discussed above with regard to the relationship of PRN and regular medication,
Geffen et al (2002) found that both receipt of PRN medication and greater frequency
of PRN administration were significantly associated with morbidity, which was also
significantly associated with the receipt of both PRN antipsychotics and
benzodiazepines. This echoes Walker’s (1991) earlier finding that the 4% of patients
who had documented side-effects after receiving PRN medication were all also
receiving regular psychotropics. McLaren et al (1990) report that while significant
reductions in conflict behaviours occurred within 30 minutes of receiving PRN
medication, sedative effects were also significantly increased. Sleepiness was also
reported as an unwanted side-effect by Vitiello et al (1987), which occurred in just
over 5% of PRN administration, while acute dystonia occurred in just 0.24%.
However, this might be an underestimate of the true prevalence of side-effects, as
Geffen et al found that no doctors and only 4% of nurses among their participants
specifically included an assessment of possible side effects when describing their
assessment of the effectiveness of PRN medication.
Another potentially harmful outcome of PRN use highlighted in the literature is the
risk of falling. Aisen & Deluca (1992) found that falls among geropsychiatric patients
who had suffered falls had received significantly more frequent PRN doses of
benzodiazepines than patients who had not fallen. Patients who had fallen were also
found to have received more frequent doses of neuroleptics, although this finding
was only marginally significant.
2.10
Relationship of PRN use to other containment methods
PRN medication is only one of a range of methods that can be used to contain
disruptive and dangerous behaviour. It is not necessarily the first or only containment
strategy to be used, and the principle of using the least restrictive containment
method necessary is well established in clinical practice. McLaren et al (1990) found
that 12% of PRN administrations on a medium secure unit were associated with
manual restraint, and that in most incidents, PRN was administered after other
interventions had been attempted, including talking with the patient (74%), attempting
to distract the patient (35%), sending the patient to his/her room (29%), ignoring the
patient’s behaviour (19%), and relaxation (7%). Curtis et al (2007) also found a range
of interventions that had been attempted before administering PRN medication for
25% of incidents where PRN medication was used. These included talking with or
counselling the patient (17%), distraction (5%), seclusion or time-out (4%), giving
practical assistance (1%), and observation and review by a doctor (1%). Just over
2% of patients who received PRN medication were transferred to a locked, highsecurity observation unit. Therapeutic interventions in addition to PRN were more
likely to be applied if the rationale for administering PRN related to psychotic
symptoms, agitated/angry/aggressive behaviour, elevated/upset/angry behaviour,
and sleep. Swart et al (2011) report similar results to Curtis et al in their study of PRN
use in a child and adolescent inpatient unit, with other therapeutic interventions being
attempted in just over a quarter of incidents where PRN medication was
administered, including talking with/counselling the patient (17.2%), distraction
(4.5%), seclusion or time-out (4.1%), practical assistance (0.8%), observation (0.4%)
and review by a doctor (0.4%). The fact that other interventions were apparently not
28
attempted in around three-quarters of the incidents reported by Curtis at al and Swart
et al suggests that PRN medication could be the primary intervention within inpatient
care. However, it could easily be the case that other interventions are simply not
documented as frequently as they occur, especially given the fact that ward
environments are typically very busy, and that the accountability associated with
administering medication (and seclusion and manual restraint) need not necessarily
apply to other therapeutic interventions. It is not necessarily mandatory to document
‘talking’ interventions, and reporting might be incomplete where documentation is
mandatory. As we have seen, it is common for key information (such as the reason
for PRN administration and its effects) not to be recorded when PRN administrations
are documented. Nurses might also underestimate the therapeutic value of what they
might regard as quite unremarkable interactions with patients. This lack of reporting
of other interventions is suggested in Swart et al’s finding that other therapeutic
interventions were more likely to be documented when a rationale for the
administration of PRN is recorded, which is similar to Curtis et al’s finding that other
interventions were more likely to be applied (or rather, documented) when PRN is
used to contain symptoms and quite disturbed behaviour.
2.11
Alternatives to PRN and their use.
While pharmacological interventions are a cornerstone of inpatient psychiatric
treatment and PRN medication is an important part of this, its use is not without
criticism. Curtis et al (2007) comment that allowing or encouraging mental health
nurses to rely upon PRN medication as the main containment strategy does them a
disservice, and that their skillbase should be expanded in both undergraduate and inservice training. Thapa et al (2003) argue that PRN use can expose patients to
unnecessary psychotropic medications. Evans & Di Scipio (1980) criticise reliance on
PRN medication because it reduces attempts to use other management strategies
that have the potential for teaching self-regulation and control. Donat (2005) echoes
this, arguing that relying on the sedative effect of psychotropic medication can make
it less likely that patients will develop the daily living and coping skills needed to
function outside of inpatient settings, and that PRN benzodiazepines are
contraindicated for a large proportion of psychiatric inpatients who have a history of
comorbid alcohol and drug misuse. Furthermore, the unnecessary reliance upon
PRN medication (along with seclusion and restraint) for behaviour management has
been a primary focus of human rights litigation. Other concerns around perceived
abuse or unethical use of PRN include its potential for being used to quieten patients,
rather than taking the time to explore behaviour therapeutically (Usher et al, 2009).
2.11.1 Regular medication as an alternative to PRN medication: The need for
PRN medication could arguably be reduced by changing clinical practice
around regular medication. Mason & Dewolfe (1974) found that: 62% of
patients prescribed PRN antipsychotics were receiving regular antipsychotic
medication at a dose below what was rated as a conservative high-dose level.
Increasing the dosages of regular medication might therefore reduce the need
for PRN medication, and this strategy is mentioned by a doctor participating in
Usher et al’s (2009) study of clinical decision-making for PRN medication.
Another alternative to PRN medication involves changing the scheduling of
regular medication. Perlman and Hogben (1977) found that by administering
regular medication at earlier times than had previously been the case,
significantly fewer PRN doses of tranquilizers and hypnotics were
administered per patient-day. Several explanations were offered to account
for this. Firstly, the altered standing dosage times were brought into closer
alignment with the termination of visiting hours, which are a time when
patients are in contact with people who are familiar and significant to them,
29
but who can therefore be the ones with whom interpersonal conflict is most
likely, and a heightening of symptoms can often result from visits.
Administering standing doses of medication at the end of visiting hours might
therefore reduce the need for PRN doses to treat evoked symptoms. Also, the
first scheduled medication time was brought into alignment with the time at
which patients meet privately with their nurse, another situation which can
provoke anxiety in patients. Later administration of night-time medication
might also mean that their sedative effects would be likely to reduce the need
for PRN medication to treat insomnia. It was also noted that the revised
medication times were more convenient for staff, and might have meant that
staff had more time for therapeutic activities with patients that would reduce
the need for PRN medication even further. Unfortunately, the times of
administration of PRN medication were not recorded in either the baseline or
intervention stages of the study, so the temporal relationship between the
administration of regular and PRN doses could not be directly examined, and
because the baseline period coincided with the arrival of new resident
medical staff, they would have been more experienced by the time of the
intervention phase, and this might also have affected the amount of PRN
medication that was administered. Nevertheless, the study strongly suggests
that alterations in regular medication administration practices could reduce
the need for PRN medication, and might therefore constitute a valid
alternative.
Several of the studies reviewed found that treatment with atypical
antipsychotics led to a reduction in PRN use. Ratey et al (1993) found a
decrease in PRN use amounting to nearly 25% in four out of a group of five
aggressive inpatients after they began treatment with clozapine. Hoff et al
(1996) report a significant decrease in total PRN use after 12 weeks of
clozapine treatment compared to baseline PRN administration rates, but while
there was a significant reduction in non-neuroleptic PRN, there was also a
non-significant increase in neuroleptic PRN administration.. Chengappa et al
(1999) found a significant reduction in the prescription of PRN lorazepam and
a non-significant trend towards a reduction in PRN neuroleptics in a small
sample of psychotic female patients with borderline personality disorder who
displayed both severe deliberate self-harm and aggression. Parepally et al
(2002) found a significant reduction in the use of PRN antipsychotics in a
group of patients treated with olanzapine, compared to a group of patients
treated with either typical antipsychotics or risperodone. Megna et al (2007)
report a significant reduction in the use of PRN medication after six months of
treatment with atypical antipsychotics (compared to one month before
commencing atypical antipsychotic treatment). This was accompanied by
clinical improvements which, while significant, were not clinically robust (no
patients were dischargeable), although it was suggested that the
improvement may improve the patients’ ability to engage in psychosocial
treatments. A significant increase in the number of patients requiring
anticholinergics also occurred. Hatta et al (2009) found that a group of
inpatients treated with aripiprazol had a significantly higher rate of IM
haloperidol PRN, compared to groups of patients treated with risperidone,
olanzapine, and quetiapine. Finally, Bastiampillai et al (2009) reported on a
single case study of a patient in whom administration of PRN medication
reduced from ‘significant’ (although unspecified) to zero after four weeks of
clozapine treatment. Encouraging though these findings appear, all but one of
these studies are characterised by small groups of patients (Ratey et al,
1993; Hoff et al, 1996; Chengappa et al, 1999; Megna et al, 2007; Hatta et al,
2009; Bastiampillai et al, 2009), absence of randomisation (Megna et al,
30
2007; Hatta et al, 2009), one is of patients on a single unit, the results of
which might therefore not be easily generalisable (Parepally et al, 2002), and
two (Ratey et al, 1993; Megna et al, 2007) were retrospective studies, which
are vulnerable to recording biases, especially where aggression is concerned.
One study (Megna et al, 2007) had no control group, another, while it
recruited to power, had a low participation rate (Hatta et al, 2009), and the
results of another which investigated the effect of changing regular
medication to clozapine (Hoff et al, 1996) might have been blurred because
some patients were being treated with combinations of typical and atypical
antipsychotics at baseline.
2.11.2 Non-pharmacological alternatives: The disadvantages of PRN medication
discussed above clearly suggest that effective non-pharmacological
alternatives to it are desirable. Usher et al (2009) report that most clinicians
participating in their study agreed that PRN should only be administered after
alternatives had been tried and found unhelpful. Geffen et al (2002) found that
nursing staff identified more non-pharmacological alternatives to PRN
medication for managing both agitation and psychotic symptoms than
doctors, and that nurses reported using non-pharmacological alternatives
more frequently than doctors. However, experience seems to also play a role,
as junior staff (both nursing and medical) had less knowledge of nonpharmacological alternatives than senior staff. However, while participants in
Baker et al’s (2007b) study of clinicians’ PRN medication practices listed a
total of 22 alternatives to PRN (the most commonly cited being spending
more time with nursing staff, anxiety management, de-escalation, and
distraction), almost all could identify instances where PRN had been used
when preferable alternatives existed, and implied that PRN medication tended
to be a measure of first resort, because other factors such as to limited skills,
limited clinical experience, time pressure, or low/inadequate staffing levels
prevented the use of alternatives. A downward prioritising of therapeutic
activity in acute inpatient settings was also reported. These findings echo
those of an earlier study of inpatient service users’ experiences of PRN
medication (Baker et al, 2006). While 45% of the participants identified
alternatives to PRN, including talking (counselling) and recreational activities,
few had tried these because of a perceived lack of support or opportunity to
use them. Other evidence also suggests that the use of non-pharmacological
alternatives alone is somewhat rare. Craig & Bracken (1995) found this to be
the case in only slightly over 13% of interventions recorded in their study. Of
course, as discussed earlier, it is likely that non-pharmacological interventions
are applied successfully by clinicians before a potentially risky situation
reaches the point where it is recognised as such and are therefore not
recorded.
A range of non-pharmacological interventions as alternatives to PRN
medication are examined in the studies reviewed. These include the effect of
working practices, psychosocial interventions, and ward environment on the
rate of PRN medication use.
Perhaps the most basic level of psychosocial intervention is to perform a
psychiatric assessment. Wise et al (1989) found that patients in a general
hospital setting who were prescribed haloperidol were often elderly, seriously
(physically) ill, had inpatient stays that were longer than average, and 80% of
them were prescribed haloperidol on a PRN basis. Two-thirds of the patients
did have a psychiatric diagnosis, primarily organic mental disorders, and the
most common reason for neuroleptic treatment was to manage severe
31
agitation. Only 23% of patients who had been prescribed haloperidol had
received a psychiatric consultation, but these were significantly less likely to
actually receive PRN haloperidol; they were also significantly younger than
those who did not receive a consultation. While this suggests the value of
psychiatric assessment in reducing the use of PRN medication, this was a
study of non-psychiatric patients in only one hospital, which was a
retrospective casenote review and therefore prone to recording biases (the
study mentions that poor documentation regarding haloperidol use was
common). Another study highlighting the potential value of different working
practices in reducing the use of PRN medication is by Alexander (2006). This
study compared the nursing regimes of two acute psychiatric units, focussing
on ward rules as a means of investigating the relationship between the
flexibility or inflexibility of the regimes and patient outcomes. PRN use
appeared to be associated with high levels of ward incidents. The
correspondingly low levels of ward incidents and PRN use could have been
linked either to higher levels of structure and organisation on the ward, or to
an oppressive ward atmosphere resulting from an over-zealous enforcement
of ward rules associated with very high levels of ward structure. It should be
borne in mind that this study has a possible source of bias, as patients were
only allowed to participate if staff considered that this would not be distressing
for them.
Several of the reviewed studies looked at the effect of introducing training in
and the use of non-pharmacological interventions on the rate of PRN
medication use. Donat (2006) describes how introducing a review procedure
resulted in a reduction in the use of seclusion, restraint, and PRN medication
in a psychiatric rehabilitation setting. PRN medication use in the hospital
studied was monitored weekly, and patients who received three or more
doses of PRN medication in a week were identified. The clinical team was
then instructed to carry out a review of issues related to the use of PRN for
that patient. If indicated, a behavioural assessment was conducted in order to
understand factors affecting problems which precipitated the use of PRN
medication, and alternative self-management strategies and/or behavioural
strategies to be implemented by staff were developed and implemented. Staff
received training in the identification of behavioural chains which precipitated
the use of PRN medication, and in how to proactively encourage and
reinforce preferred activities, and to capitalize upon differential reinforcement
procedures for preferred behaviours during non-critical times. These efforts
were supported by having a readily accessible behavioural consultation
service. The number of patients who received three or more doses of PRN
medication fell significantly (by nearly 40%) one year after the programme
had been initiated, compared to the pre-intervention baseline. While this is an
encouraging finding, it must be remembered that the study was carried out in
one comparatively small hospital, so the extent to which the results can be
generalised to other settings is unknown. Also, the ready availability of
behavioural consultation services and the high level of staff training that
underpinned the intervention means that it might not be easily applied to other
settings. The use of behavioural approaches which appeared to reduce the
use of PRN medication is also described in two single case studies that were
reviewed (Beal & Delaney, 2005; Bisconer et al, 2006).
Brakoulias et al (2010) investigated the characteristics of patients admitted to
a Psychiatric Emergency Care Centre (PECC) in the first six months of its
operation, comparing them to those admitted to its forerunner in the six
months prior to the opening of the PECC. The previous unit was housed
32
within a large tertiary referral emergency department, while the newer facility
was opened as a separate unit adjacent to it. While there were no significant
differences in the proportion of aggressive patients admitted to the units
during the study period, there was a significant reduction in the number of
PRN doses of haloperidol and midazolam that were administered in the
PECC, and there was also significantly less use of physical restraint. This
was attributed to the PECC staff possibly being better trained to deal with
aggressive patients with non-pharmacological interventions (unspecified),
especially given that there were no significant differences between the units in
other PRN medications that were administered. However, data were collected
by retrospective file audit, and the level of diagnostic agreement between the
two units was not established. The study was also unable to control for
changes in policies and clinical practice that usually accompany the opening
of a new service which might also have influenced the outcomes.
Despite their limitations, the studies reviewed above suggest that
psychosocially-based, non-pharmacological interventions may be valuable in
reducing the use of PRN medication. However, other studies paint a different
picture. Craig & Bracken (1995) considered that over 75% of nonpharmacological interventions that were attempted in their study were
ineffective (although no data concerning the nature of these ineffective
interventions are presented), and most had to be followed by PRN
medication, which was reported as being effective in approximately 75% of
cases. Dean et al (2007) report the results from a behavioural management
programme in a child and adolescent psychiatric inpatient unit, which
consisted of staff training in behavioural management skills, individualised
patient management plans, and a standardised framework for behavioural
management by staff. The objective was to improve staff competence, create
high therapeutic input for patients, and ensure consistent reinforcement of
appropriate behaviour and management of disruptive behaviour and
aggression with a hierarchy of responses. While the programme led to a
significant reduction in aggressive incidents, the use of manual restraint, and
duration of seclusion, there was only a slight (and non-significant) reduction in
the use of PRN sedation. Again, this was a retrospective casenote study, and
therefore vulnerable to recording biases – indeed, the authors point out that
the recording of PRN sedation was incomplete for 21% of their sample.
Beaulieu et al (2008) looked at the outcomes of training staff in an acute brain
injury unit in behavioural management. This involved the identification of
levels of escalation and interventions appropriate for each level, including
verbal interventions and personal safety techniques, but was not found to
reduce the need for PRN medication.
Two of the papers reviewed found that training in non-pharmacological
alternatives to PRN medication can actually increase the level of PRN use.
For example, Beaulieu et al. (2008).found that use of PRN clonazepam and
antidepressants both increased significantly, despite the training in verbal
interventions and personal safety techniques that staff received. Colenda &
Hamer (1991) examined staff interventions before and after a training
programme on the management of aggression in a geropsychiatric unit. They
found that, after training, staff interventions for aggressive behaviour in the
non-dementia patients remained similar to those reported in the pre-training
survey, while with the dementia patients non-pharmacological interventions
were used less frequently, and PRN medication (either alone or in conjunction
with seclusion or restraint) were used more frequently. Colenda & Hamer
speculate that before training, staff may have used interpersonal interventions
33
indiscriminately, which may have paradoxically escalated the cycle of
violence, and the training expanded their repertoire of intervention strategies,
making interventions more closely targeted, with flexible use of PRN
medication, seclusion and restraint, in addition to better targeted interpersonal
interventions, interrupting the cycle of violence. A possible explanation for
these paradoxical findings might be that training might change staff views of
the value of PRN, making them more comfortable with its use, and so making
them more willing to use it than they had been previously.
The effects of a nurse-led activity programme (rather than a behavioural or
psychological intervention as such) on the use of PRN medication is
described in Thomas et al (2006). A daily activities programme was
implemented on two locked high-dependency units. This consisted of a onehour movement to music session in the morning, and a 15-minute relaxation
session in the afternoon, providing opportunities to introduce a daily routine,
improve and maintain physical fitness, increase daily structure and cognitive,
social, and interpersonal skills and self-esteem. This was effective in
significantly reducing PRN administration on one of the units, compared to
baseline. Both units served different catchment areas. The unit where a
significant reduction in PRN was observed served an affluent, middle-class
area, while the other served a deprived inner-city area from where patients
were usually brought to the unit by police. Again, while these results are
broadly encouraging, PRN medication was the only containment measure
that was studied, so other interventions that might have been used instead
were not recorded. Furthermore, the hospital’s computerised patient
administration system was unable to provide data concerning the
characteristics of the patients who were resident on the ward during the
intervention, so it could not be ascertained whether any changes in these
patient characteristics during the intervention period might have occurred and
affected PRN use. Inaccurate data collection by ward staff is also mentioned
by the authors.
The importance of a comfortable ward environment and of structured,
therapeutic activity in inpatient units for recovery has long been recognised
(Royal College of Psychiatrists, 2011). One of the studies reviewed examined
an intervention based along these lines. It is also the only study reviewed that
explicitly considered the health economic aspects of an intervention, although
Smith et al (2008) do mention in passing that the availability of PRN
medication enables cost savings to be made by healthcare providers because
it does not require a physician to administer it, and that eliminating PRN
orders means that time spent on preparing, administering, and documenting
the use of them is saved (which has cost implications). Nanda et al (2011)
examined the effect on PRN use of exposure to three different paintings in the
unit lounge, and compared this with PRN use in a control condition where no
art was displayed. The annual PRN cost per condition was calculated from
the data. There was a significant reduction in PRN use when an artwork
depicting a realistic nature scene (a photograph of a savannah) was
displayed, as opposed to an abstract artwork and an abstractrepresentational image. Total cost per PRN incident was calculated to be
$60.30. Based on the amount saved comparing PRN use during the display
period for the image of the realistic nature scene compared to the control
period, the annual saving for the hospital in terms of unrecovered cost for the
nature artwork was calculated at $3,183, and annual saving for patients at
$15, 272. Because the artwork for the intervention had been donated, and
installed by the university conducting the trial, the cost of the intervention was
34
minimal, but assuming a yardstick of $2,000 for an artwork of similar size, the
data suggested that this cost would be recoverable within one year. While this
study is interesting, its generalisability is limited because only one hospital
was studied. Also, because only one unit was studied, the paintings were
displayed successively, so an order effect might have imposed a bias towards
the realistic nature scene, as this was the last to be displayed. Furthermore,
there was no post-intervention follow-up, for example, by continuing to display
the most effective image (once it had been identified) after the intervention
period while continuing to monitor PRN use. Therefore, the possibility of a
Hawthorne effect occurring, and then diminishing as the novelty of the image
faded over time cannot be discounted. Finally, PRN was the only intervention
studied, so if levels of anxiety and agitation among the patients remained
constant (which is unknown, as no direct measures of psychopathology were
used), other interventions might have been used instead (although staff were
blind to the fact that PRN use was being examined) which would not have
been recorded. If the use of other containment methods had also been
recorded, a more accurate appraisal of both the intervention’s effect on
reducing anxiety and agitation and of the health economic impact of the
intervention would have been obtained.
2.11.3 Is PRN medication actually necessary? The case for prohibition: The
most radical alternative is to prohibit PRN psychotropics as a matter of policy.
Thapa et al (2003) argue that the rationale underlying the use of PRN (that, in
its absence, staff would be unable to maintain a safe therapeutic
environment) has no empirical basis. Their study retrospectively audited
casenotes for unscheduled medications that were administered before and
after the Arkansas State Hospital instituted a policy banning standing PRN
prescriptions for psychotropic drugs. Two types of unscheduled medications
were examined: PRN medication, which when prescribed, can be
administered at the nurses’ discretion and statem (stat) medication, which
require a physician’s order before it can be administered on each occasion
that it is requested. After the policy was changed, the proportion of patients
receiving unscheduled psychotropic medication was found to have fallen
significantly, which was still significant even when controlling for age, gender,
race, marital status, diagnosis, substance misuse, Axis-II diagnosis, legal
status and year of first hospitalisation. It was also found that significantly more
PRN doses were administered at the patient’s request (just under a quarter,
compared to 13% of stat doses), which suggests that nurses may have
preferred not to attempt non-pharmacological interventions when PRN
medication was accessible to them, which prompts Thapa et al to question
whether PRN medication exists for the benefit of patients or staff. Compared
to the three months before the policy change, there was no significant
difference in the number of aggressive incidents, the frequency of restraint
and seclusion use, and the duration of seclusion in the first three months after
the change, and there were also no significant differences in scheduled
medication prescribing. While these results suggest the possible value of
replacing PRN medication prescriptions with stat orders, the study has
several limitations. No measures of the actual need for or functional outcomes
of the administration of the unscheduled medications was given, nor was
there any data collected on adverse reactions to PRN or stat doses, nor of
adverse consequences of not administering PRN medication or stat doses on
request from the patient. This may have been because the study was a
retrospective case audit, and this information may not have been routinely
recorded in casenotes. Also, only a single site was studied, and the study
period was relatively short. A larger study was conducted by Smith et al
35
(2008), following a similar policy change in all of Pennsylvania’s nine state
hospitals (one of these hospitals had already replaced PRN medication with
stat medication over 10 years previously). During the study unscheduled
medications (PRN and stat doses) were prospectively recorded in all of the
hospitals for six months before the change in policy, and stat doses were
recorded for 17 months after the change. By the final month of the study, both
the proportion of patients receiving unscheduled doses of medication and the
total number of doses administered had fallen significantly, compared to the
first month of baseline ratings. Verbal aggression, physical aggression
towards fellow patients, and use of mechanical restraint all fell significantly,
and while seclusion use also fell, this was not significant. Compared to the
hospital which used stat doses instead of PRN orders at baseline, patients in
the hospitals which did use PRN orders received twice the unscheduled
medication (which was highly significant), and when the other hospitals also
replaced PRN orders with stat doses, unscheduled medication use decreased
significantly. Smith et al comment that the elimination of PRN orders resulted
in staff changing the focus of their efforts onto effective intervention and
support, and increased team cohesion and therapeutic relationships with
patients. However, since the study did not directly monitor the use of
containment methods other than unscheduled medication, mechanical
restraint or seclusion, the extent to which staff did actually change their
behaviour towards patients is unclear. They also comment that eliminating the
use of PRN orders resulted in a safer hospital system. While the number of
patient-on-patient assaults did decrease significantly, the number of patient
falls, patient-on-staff assaults, episodes of self-injurious behaviour, adverse
drug reactions and medication errors were not significantly affected by the
discontinuation of PRN orders. Also, because the state hospital system had
already reduced mechanical restraint and seclusion before the study’s
baseline, and local projects were in place to reduce falls and assaults, these
initiatives may also have affected the results. There was also no examination
of how symptom severity affected the use of unscheduled medication, so it is
possible that changes in the inpatient profile might have affected the
reductions that were observed.
2.12
Perceptions of PRN use: staff, patients and others
In a qualitative study of inpatient service users’ experiences concerning PRN
medication, Baker et al (2006) found that most participants suggested that it was
useful, citing benefits such as its flexibility, availability, and calming effects (although
the effects and side-effects of some drugs made them preferred to others). Just over
half of the participants considered that the absence of PRN would have dire
consequences; while a minority (9%) did not agree that this would have negative
consequences. Particular problems reported included confusion and stigma around
the process associated with the use of PRN medication, especially when PRN
medication that they had requested was refused by staff, and particularly if no
explanation was offered, and when staff tried to initiate it, but the service user did not
want it. PRN medication was then seen as a means of control. Participants also
reported a lack of education about their PRN, although nearly a third said that they
were not concerned by their lack of knowledge, either because they trusted staff to
decide for them or because they had used PRN before without concern. However,
this tended to undermine feelings of self-sufficiency. While these findings are
interesting and largely reflect those of clinicians in a later study, the sample was selfselected, and some patients who might have expressed different views may have
been too ill to participate, or might have thought that participation might be too
stressful to consider taking part. The participants were all inpatients when they were
36
interviewed (and some were detained patients), which might have influenced what
was reported.
In a later study, Baker et al (2007b) analysed themes which emerged from interviews
with clinicians concerning their perceptions of PRN medication and its use.
Subsumed under the emergent theme of Balanced Usefulness were the advantages
of PRN medication as a means of relieving distress and in preventing and managing
violent behaviour. A subtheme focussed on "removing doctors from the process",
which had the underlying assumption that this would lead to safer and improved
patient care. There was also a small number of extracts from the interviews which
mentioned PRN use to avoid ‘bothering’ the doctor, and prescribing PRN medication
was also seen as often not primarily related to individual clinical need, but to provide
staff with reassurance. Both of these points echo Thapa et al’s (2003) concerns
regarding whether PRN medication is for the benefit of patients or staff discussed
above. The most commonly mentioned disadvantage of PRN medication focussed
around the perceived potential for misuse of PRN medication, either by nursing staff
giving too much or too quickly, or by patients (which reflects on of the findings of
Usher et al, 2009). While medical and pharmaceutical staff may have been
underrepresented among the study’s participants, the sample was generally
regarded as being representative of the range of clinicians involved in the
prescription and administration of PRN medication. However, it was a convenience
sample recruited from one (albeit large) city, so the findings may not be entirely
representative.
Whittington et al (2009) found that PRN medication was among the three most
approved-of containment methods among both inpatient service users and staff who
participated in a survey of approval of various coercive measures commonly used in
acute inpatient care. Personal experience of either using or receiving PRN
medication appeared to be important in this, as staff who had administered PRN
medication (or any of the coercive methods listed) were significantly more approving
of it than those who had not, and service users who had received PRN medication
were significantly more approving of it than those who had not. However, while this
survey was large and representative of the three regions in England where it was
conducted, the sample is not representative of the whole of England. As in Baker et
al (2006), staff involvement in the recruitment of the inpatient service users who
participated may have introduced bias. Also, no data was collected on the service
user participants in terms of diagnosis, or type of unit, nor of assault rates in the
participating units, all of which may have influenced the results. The study also
assumes a consistent attitude towards coercive interventions which is stable across
situations, where attitudes might actually differ in relation to the circumstances and
situations in which they are deployed. Attitudes might also be affected by assault
rates in participating inpatient services at the time that the survey was conducted.
The general public also has opinions about coercive methods in general, and the use
of PRN medication in particular, which appear to be less positive than those of
service users and clinicians. In an attempt to examine these, Muir-Cochrane et al
(2009) surveyed university students’ attitudes to containment methods, comparing
those of psychiatric nursing students with those of students who were not studying
psychiatric nursing. PRN medication received the second-lowest method-specific
approval rating from non-nursing students, who were also significantly less approving
of PRN medication than mental health nursing students. However, these findings
might have been affected by the fact that only half of the sample pool of nursing
students participated in the study, while data collection among the non-nursing
students took place in May and June, when most such students had completed their
studies for the year and were therefore less likely to be on campus. While these
37
findings are interesting, they cannot be considered representative of the opinions of
the wider public as they were obtained from an unrepresentative sample.
3
DISCUSSION
3.1
Summary
PRN medication is a frequently used containment strategy in inpatient units. If
it is used, it is most likely to be administered in the early stages of admission,
and its use diminishes as the duration of the inpatient stay increases. Its use
may be more common among formally detained patients, but the evidence
here is mixed. It is often used alongside other containment strategies, and is
often prescribed alongside regularly scheduled medication. This means that
there is a risk that, if it is administered, PRN medication can lead to
unintended high doses, or potentially significant drug interactions, but these
appear not to be common in practice. On the whole, both clinicians and
service users are in favour of it.
While the evidence is mixed regarding the age and gender of the typical
patients who receive it, it appears that non-White patients are more likely to.
This might be due to racial stereotypes influencing clinicians’ perceptions of
the behaviour of non-White patients (and therefore decision-making regarding
its prescription and use), a higher level of acuity of symptoms in this patient
group, or a lack of effort made by clinicians to encourage meaningful
engagement in treatment. Psychosis (especially when chronic), mania, and
personality disorder have all been associated with the receipt of PRN
medication in adults, and child and adolescent inpatients with developmental
disorders more likely to receive it, probably because of the impulsive
behaviour that is associated with impairments of executive function in these
disorders. In terms of specific antecedents of its use, agitation and insomnia
are most commonly reported, and PRN medication is likely to be effective in
addressing the reason for its administration in around half of the occasions
when it is used. In common with other strategies to contain disruptive and
dangerous behaviour in inpatient settings, a small group of patients receives
a disproportionate amount of PRN psychotropics. Among adults, these
typically have diagnoses of psychotic disorders and bipolar affective disorder,
while children and adolescents typically have a diagnosis of a psychotic
disorder and a significant pre-admission history of aggressive and/or other
disruptive behaviour
Clinicians tend to describe clinical decision-making around the use of PRN
psychotropics as determined by assessment of the patient’s history, mental
state, and risk, as well as consideration of the needs of other patients on the
ward, and emphasise that PRN medication should only be used when other,
less restrictive interventions have been attempted and found to be
unsuccessful. However, some medications appear to be routinely prescribed
for PRN use irrespective of any assessment of the patient’s needs, and PRN
use can be influenced by contextual factors, such as the general level of
activity and disturbance on the ward, the number of staff on the ward
(particularly qualified staff), the perceived degree of competence of these
staff, and their degree of familiarity with the patients.
It may be possible to decrease the use of PRN medication by changing the
dosages or drugs in regular medication prescriptions, or by altering the times
at which regular medication is scheduled, by the use of non-pharmacological
38
interventions that address the conflict behaviours, or by improving the
therapeutic impact of ward environments by making changes to working
practices, organisation, and structure.
3.2
PRN use and the City Model
Most of the studies were concerned with describing the circumstances of
PRN use, its effects, and the characteristics of patients who received it, and
so PRN medication as a vehicle whereby more therapeutic transactions
between clinicians and patients could be enabled by it received scant
attention. The idea that non-pharmacological processes could also be at work
when PRN medication is administered was discussed in two studies (Evans &
Di Scipio, 1980; Mclaren et al, 1990), although several studies comment that
PRN medication is anti-therapeutic, in that its use tends to reduce attempts at
other (psychosocial) management approaches and undermines the nurse’s
role in promoting coping and self-management strategies (Evans & Di Scipio,
1980; Thapa et al, 2003; Curtis et al, 2007; Usher et al, 2009).
However, several of the studies reviewed did have findings that related to
some aspects of the City Model. While they are all have methodological
shortcomings, taken as a whole they do suggest that the use of PRN
medication can be reduced. Two studies found that aspects of ward structure
were potentially involved in the use of PRN medication. Perlman & Hogben
(1977) found that altering regular medication times to bring them into
alignment with time that are potentially upsetting for patients (visiting hours,
ward rounds, etc) may have been effective in reducing PRN medication use.
Ironically, one of the confounding variables that raised some doubt as to
whether this was actually true, the fact that ward medical staff would have
been more experienced by the time that the intervention was put into effect, is
in itself suggested by the Technical Mastery component of the model.
Alexander (2006) found that low levels of ward incidents (and hence low
levels of PRN use) could be linked to higher levels of ward structure and
organisation, although the study acknowledges that the low levels of conflict
might also be caused by an oppressive ward atmosphere caused by this very
level of structure and organisation. The Technical Mastery component of the
model is also reflected in Geffen et al’s (2002) finding that the more senior
medical and nursing staff were, the more knowledge they had of nonpharmacological alternatives to PRN use, and in Usher et al’s (2009) finding
that staff who were less familiar with the patients on the ward were more likely
to administer PRN. Sonntag et al (2006) found that institutional characteristics
influence the likelihood that PRN medication will be used, particularly the
levels of qualified staff and their perceived level of competence, which is
clearly in line with the Organisational Support aspect of the City Model,
insofar as the need for the organisation to provide specialist training (Bowers,
2002, p.146). Curtis et al (2007) also comment that nurses’ skillbase should
be expanded in both undergraduate and in-service training. Most of the
findings that are relevant to the City Model pertain to the its High Therapy
component, as these results concern the effect of increased or improved
therapeutic input on PRN use. Donat (2006) and Dean et al (2007) both
report on initiatives to improve and increase therapeutic input which led to a
reduction in restrictive containment methods in general and PRN use in
particular. In their single-case study, Beal & Delaney (2005) illustrate how the
need for PRN medication (and seclusion) was reduced after a programme
was initiated which distracted the patient from his feelings, reinforced selfregulation, and developed self-efficacy. Thomas et al (2006) describe how a
39
daily programme of gentle exercise and relaxation provided opportunities to
introduce a daily routine and add structure to the day, while
improving/maintaining physical fitness and improving cognitive, social, and
interpersonal skills may have reduced PRN use, while Smith et al (2008)
suggested that, as well as reducing the number of unscheduled medications
that were administered, replacing PRN medication with stat medication led to
the encouragement of a change of focus on nurses’ efforts, towards effective
intervention and support and increased team cohesion and therapeutic
relationships with patients (although no evidence is presented to support this
claim). However, such efforts to increase and improve therapeutic input need
not necessarily be successful, as two studies (Colenda & Hamer, 1991;
Beaulieu et al, 2008) found that staff training in verbal interventions to reduce
the use of PRN medication were not successful, and, paradoxically, increased
its use. This may be a point that the City Model has missed – that increased
Technical Mastery might not mean that staff eschew more restrictive
containment methods in favour of more therapeutically-based ones; in fact,
the improved confidence derived from increased Technical Mastery, along
with a fuller understanding of the limits of less restrictive interventions under
certain circumstances, may well increase the use of more restrictive
interventions
3.3
Lessons for future research
A major problem identified in the studies reviewed was their small size and
limited geographical scope, making the generalisability of their results
problematic. Large, multi-site studies are the obvious remedy to this problem.
Many of the studies relied upon retrospective casenote audits. A problem
highlighted in several studies was the poor quality of information recorded in
the notes. This included missing information on the antecedents of PRN use
and on other containment strategies that had been unsuccessfully attempted
or were used either concurrently with or after administering PRN medication,
imprecise or absent information on its effectiveness, and lack of indication of
side-effects or their absence. This strategy is therefore clearly inadequate to
the task of obtaining high quality data.
A related problem was that in some studies, because PRN medication was
their specific focus of concern, the use of other containment strategies was
not recorded. It is clearly important that this information is recorded, as it will
reveal the relative use of different containment strategies in relation to
different conflict events. Not only is this important in its own right, but
comparison of this data between services and clinical settings may be very
revealing and useful. Another problem regarding the quality of the information
recorded is the fact that only one study used an objective assessment of
symptom severity (and that was only because the usefulness of the scale for
possibly reducing PRN use was itself being investigated). Again, recording
data on the severity of symptoms or other antecedents of PRN use (and other
containment strategies) according to well-defined criteria would give a clearer
idea of whether PRN medication (or other containment strategies) is likely to
be an effective measure in resolving the situation, or whether the strategy is
too restrictive for a given situation at a given level of severity. All of the
information indicated here needs to be recorded prospectively, using data
recording instruments which have clear definitions.
40
The statistical significance or otherwise of observed differences between
patients who had received PRN medication and those who had not in relation
to age, ethnicity, gender, etc. should also be indicated.
Finally, there was a lack of consideration of the health economic implications
of PRN psychotropic medication use in the studies surveyed. Studies which
identify healthcare costs in relation to different containment methods, and
which identify potential cost-savings associated with certain containment
strategies as well as the possible offsetting of other costs would be a valuable
resource in guiding training, policy, and practice.
Taken together, these measures would greatly improve the methodological
quality of future studies, making comparisons across studies and between
settings possible, and providing clearer evidence upon which to base policy
and practice.
41
4
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