Download accuracy of text entries within a manually compiled anaesthetic record

British Journal of Anaesthesia 1992; 68: 381-387
ACCURACY OF TEXT ENTRIES WITHIN A MANUALLY
COMPILED ANAESTHETIC RECORD
L. ROWE, D. C. GALLETLY AND R. S. HENDERSON
SUMMARY
We have examined the accuracy of text entries
within a manually compiled anaesthetic record by
comparing the record of the anaesthetist with that
of an observer, present throughout the procedure
but whose sole purpose was the documentation of
perioperative events. Eighty-six items of information were analysed for accuracy from 197 records.
The mean proportion of omissions was 35% and the
mean proportion of incorrect entries was 3.4%.
Where no entry should have been made, the mean
proportion of unwarranted entries was 1 %. Accuracy varied according to the information contained; however, omissions were common for
preoperative status, fluids, tourniquet use, aspects
of monitoring, local anaesthesia and intraoperative
problems. The most consistently accurate information was the description of the patient and that
relating to intraoperative i.v. drug use. Inaccuracy
was common for the majority of sites on the record,
irrespective of their reflecting on the anaesthetist's
performance. We suggest, therefore, that the reason
for this inaccuracy of data was not related principally to anaesthetists' defensiveness, but may
reflect their attitudes to the record's value and
response to inadequacies in its design. The observed deficiencies in recording accuracy may affect
patient safety during future anaesthesia and has
relevance to medico-legal and epidemiological
research.
KEY WORDS
Records, anaesthesia. Accuracy.
The manually compiled anaesthetic record is recognized widely as being an important component of
anaesthetic care [1]. Studies have shown, however,
that when recording physiological variables, anaesthetists tend to understate extreme values and
smooth out normal physiological fluctuations [2-6].
Although some authors consider this to be " clinically
relevant filtering of physiological artefact" [5] and of
no real significance, others suggest it represents an
anaesthetist's unconscious defence strategy, fewer
extreme recordings implying better case management [4]. In a recent survey of New Zealand
anaesthetists, data manipulation (either intentional
omission or the recording of incorrect information)
was found to be a common and conscious act [1].
Previous studies of the accuracy of the anaesthetic
record have focused on the accuracy of physiological
recordings. However, these make up only a part of
the total record content and their correct interpretation requires a knowledge of the additional text
entries which specify the drugs, their time of
administration and dose, fluids administered, ventilatory information and problems encountered. To
our knowledge, no comprehensive study has examined the accuracy of these accompanying data. In
this study, we examined the accuracy of these text
entries by comparing the actual record produced by
anaesthetists with that of an anaesthetist observer
who took no part in the anaesthetic management and
whose sole function was the compilation of an
accurate and comprehensive account of the perioperative course.
METHODS
The study was conducted over a 4-month period at
a large New Zealand public hospital. After prior
approval from the Ethics Committee, anaesthetists at
that hospital were informed that an observer would
be present throughout some of their cases and that
the purpose of this was to audit the methods of
anaesthesia used within the department. They were
not told the exact nature of the study and none knew
until immediately before induction of anaesthesia,
that a specific case was being observed.
Two hundred patients undergoing general or
major regional anaesthesia were studied. They were
selected at random on the morning of surgery from
operating theatre schedules and included patients
undergoing gynaecological, orthopaedic, ENT, ophthalmological or general surgery. Owing to time
constraints, cardiothoracic and neurosurgical cases
were excluded, as were cases expected to last longer
than 3h.
From the time of arrival in the operating theatre
area until discharge from the recovery room, all
patients were accompanied by an observer, a postFellowship registrar with 5 years experience in
L. ROWE, M.B., CH.B., F.C.ANAES.J R. S. HENDERSON, M.B., CH.B.,
F.F.A.R.A.C.S. ; Department of Anaesthesia, Dunedin Public
Hospital, Dunedin, New Zealand. D. C. GAIXBTLY, M.B., CH.B.,
F.C.ANAES., F.F.A.R.A.C.S.; Section of Anaesthesia, Wellington
School of Medicine, Wellington, New Zealand. Accepted for
Publication: November 14, 1991.
Correspondence to D.C.G.
BRITISH JOURNAL OF ANAESTHESIA
382
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FIG. 1. The anaesthetic record form.
anaesthesia. The observer took no part in the clinical
management and communicated with theatre staff
only when this was essential (in one case the observer
took over for a short period when the anaesthetist left
to attend an emergency).
The observer entered intraoperative data onto a
comprehensive five-page record. This included information which would be entered normally onto the
case note anaesthetic record, and additional information detailing the anaesthetic course and sys-
tem errors (the subject of a separate paper). Data
included all aspects of drug, gas and fluid administration, i.v. cannulation, monitoring, breathing
system and ventilation variables, positioning, tourniquet use and local anaesthesia administration. All
abnormal physiological events noted by the observer
were recorded, as were all problems and system
errors. Where non-invasive arterial pressure monitors were used (Dinamap), all digital recordings were
noted. The patient's preoperative condition was
ACCURACY OF ANAESTHETIC RECORDS
assessed and recorded by independent clinical examination, reference to case notes and laboratory
investigations.
Two days after anaesthesia, each patient's case
records were retrieved and a copy of the actual
anaesthetic record was made. This record comprises
four sides (two sheets) for data collection, two
covering the intraoperative period. The first of these
(fig. 1) includes the text entries and is intended as a
comprehensive summary of the anaesthetic course. A
carbon copy of this sheet is kept for computer entry
and later departmental review of such matters as
changing patterns of drug utilization, trainee supervision and intraoperative complications. This summary sheet was the subject of the present study. The
second intraoperative data sheet comprises a graphical record of physiological measurements. While
some anaesthetists include drug and fluid information on this graphical record, it is expected by the
department that an accurate summary appears on the
text entry sheet.
The anaesthetic record examined in this paper is,
in our opinion, representative of traditional manually
compiled records in widespread use, although it may
specify in more detail than others, the entries
required. As is currently a common trend, this
itemized format had been chosen because entries
were intended for computer input.
The data from the observer's and die actual
patient record (summary sheet) were categorized and
entered onto computer spreadsheets (Statview SE)
for statistical comparison.
RESULTS
In three cases an anaesthetic record could not be
found within the patient's case notes. Examination of
record accuracy was therefore limited to the remaining 197 records.
Eighty-six specific items of information from the
anaesthetic record (fig. 1) were examined for accuracy and for each item we calculated the number of
records in which:
(1) entry of that item was expected (E);
(2) the expected entry had been omitted (O);
(3) the expected entry was made but was incorrect
(i);
(4) no information should have been entered but
an inappropriate entry was made (N).
From these were calculated the proportion of
omissions (O/E), the proportion of incorrect entries
(I/E) and the proportion of inappropriate entries
where no entry was expected (N/(197-E)) (table I).
For the 86 entry sites examined, the total number
of expected entries was 8231—a mean of 41.8 per
record. Where an entry was expected, die mean
proportion of omissions was 35% and die mean
proportion of incorrect entries was 3.4%. Where no
entry should have been made, the mean proportion
of unwarranted entries was 1 %.
Recording accuracy was greatest for demographic
information (patient name and hospital number
being attached to the record using preprinted labels).
Sites for anthropomorphic and preoperative clinical
and laboratory data showed high proportions of
383
omission. In particular, those for blood volume,
NYHAC (New York Heart Association Classification), preoperative haemoglobin concentration, and
patient height were almost invariably omitted. It is
probable that diese relate to a lack of perceived
usefulness of the data to the anaesthetist and may be
more relevant to other types of surgery not included
in this study (e.g. cardiac).
Potentially more useful data such as ASA, preoperative arterial pressure and patient weight were
also omitted commonly. For ASA, there was some
discrepancy between the observer's and anaesthetist's assessment. However, consistent with previous published studies [7], there was no apparent
trend or bias towards one extreme of values and,
where there was a discrepancy, the observer's and
anaesthetist's grading varied at most by one ASA
grade in either direction.
A number of preoperative conditions and medications were not recorded, although they could have
been influential in determining the choice of drugs or
anaesthetic technique. Because these entry sites are
open-ended, it might be expected that omissions
would be frequent. In many cases, however, the
"nil" boxes were ticked also; although possibly
ticked in error, this suggests mat anaesthetists were
unaware of these conditions and drugs. The drugs
omitted most commonly were oral contraceptives (15
records), antibiotics (six), bronchodilators (seven)
and regular aspirin (five). The most commonly
omitted preoperative conditions were smoking (36
records), hypertension (17), recent upper respiratory
tract infection (18), other pulmonary/bronchospastic
disease (21), haematological abnormalities (12), psychiatric disturbances/dementia (10) and obesity
(eight). In two records, a previous documented
history of difficult intubation was not noted. Of 29
records of patients with a history consistent with
genuine drug allergy, die fact was not noted in 16,
and in four of these cases the "nil allergy" box was
ticked.
Premedication data were omitted in approximately
15—20 % of records, although the drug was documented more commonly than dose, which in turn
was more accurate than premedication time.
Intraoperative drugs tended to be documented
more accurately dian premedicants. The most accurate were non-depolarizing neuromuscular blocking drugs, suxamethonium and the opioids. The
dose used was less accurate than the drug itself; this
was especially so for die induction agent, where the
drug was not named in 5 % of records and the dose
was either incorrect or omitted in 22 %. The volatile
agent/gas used was poorly documented (13% omitted or incorrect) and, in 11 cases, patients received
halothane for maintenance without diis being recorded (representing 9% of all patients receiving
halothane).
Fluid and i.v. therapy data were documented
poorly: 27% of fluids were not recorded and die
volume was inaccurate or omitted in 73 % of records.
Accuracy of airway information varied, die type of
tracheal tube being recorded for almost 95 % of
patients, while tube size was commonly incorrect
and cuff volume was rarely recorded. Aldiough an
BRITISH JOURNAL OF ANAESTHESIA
384
TABLE I. Data entry site: number of records where an entry was expected (E), proportion (%) of omissions (O/E) and
incorrect entries {I/E) at those sites where an entry was applicable, and proportion (%) of inappropriate entries at those sites
where no entry should have been made (Nj197-E).— = Not applicable
Omitted
Incorrect
Inappropriately
entered (%)
1
0
0
3
49
96
100
82
97
22
99
20
72
43
59
51
55
47
19
14
19
22
4
28
29
15
14
5
11
4
6
6
3
1
1
10
8
27
43
64
22
36
6
8
75
8
10
20
17
14
20
11
52
63
6
10
0
6
—
29
100
27
26
37
60
14
39
39
0
3
4
0
0
4
2
0
0
3
0
21
1
4
1
0
1
0
0
0
17
2
6
8
4
10
0
0
1
0
11
0
6
7
0
0
3
0
0
0
30
0
4
7
0
11
2
0
0
0
0
0
0
0
0
7
0
0
0
0
—
0
0
0
0
0
—
4
0
26
0
13
—
—
—
—
—
—
—
—
—
—
—
—
0
16
0
13
2
14
—
0
0
0
—
—
6
—
—
Data entry site
Date
Name
Hospital number
Operation
Weight
Height
Blood volume
Preop. AP
Preop. Hb concn
ASA
New York Heart Ass. Class.
Preop. visit
Preop. condition
Nil of note box
Current therapy
Nil curr. therapy box
Allergies
Nil allergies box
Asleep/calm/anxious
Premedicant drug
Premedicant dose
Premedicant time
Induction time
Induction duration
Preoxygenation
Anaesthesia
Position
Induction drug
Induction drug dose
Analgesic drug
Analgesic dose
Gas and vapour
Suxamethonium dose
Competitive NMB
Competitive NMB dose
Atropine/neosrjgmine dose
Other drugs
I.v. fluid type
I.v. fluid volume
Nil fluid box
Cannula size
Cannula site
Tracheal tube type
Tracheal tube size
Tracheal tube cuff vol.
Trach. tube cuff used
Oropharyngeal airway
Spontaneous ventilation
IPPV
Circle
T-piece
Other circuit
Tourniquet site
Tourniquet time
AP monitor
Dinamap (NIAP)
Direct AP
ECG monitored
CVP monitored
Temperature monitored
Urine catheter
Fl Oi monitored
Oximeter used
Nerve stimulator used
LA by surgeon box
LA block type
Lignocaine used
Lignocaine %
Bupivacaine used
Bupivacaine %
197
197
197
197
197
197
197
197
197
197
197
197
157
40
98
99
29
168
197
147
147
147
197
197
31
197
197
174
174
139
139
174
32
79
79
77
38
30
30
167
195
195
104
104
83
83
61
104
84
154
20
19
27
27
185
168
3
189
0
7
5
168
109
30
15
50
23
23
30
30
4
0
0
0
0
0
0
0
0
0
1
0
7
0
0
0
0
0
2
21
2
9
2
1
1
0
0
17
3
0
50
0
0
0
17
0
1
1
0
2
1
1
1
(continued)
ACCURACY OF ANAESTHETIC RECORDS
385
TABLE I (com.)
Data entry site
Adrenaline concentration
Other vasoconstrictor
Position (spinal/extrad.)
Spinal needle
LA complication
Death
Cardiac arrest
Hypoxia
Laryn. /bronchospasm
Hypotension/hypertension
Difficult intubation
Difficult venepuncturc
Arrhythmia
Aspiration
Vomiting
Apnoea
Omitted
Incorrect
E
(%)
(%)
17
8
13
8
11
0
0
13
16
8
9
14
33
0
3
0
29
75
38
12
82
—
—
100
69
100
56
100
67
—
100
24
0
31
0
0
—
—
0
0
0
0
0
0
—
0
oropharyngeal airway was inserted in only 61
patients, its use was documented in 89. For approximately 15 % of patients, a record of the breathing
system was omitted.
Despite its importance, both the site and timing of
tourniquet use was omitted in more than 50% of
relevant cases.
Monitoring equipment was documented most
accurately for arterial pressure and ECG ( ^ 1 0 %
omission), although for other monitors (temperature,
urine catheter, FiOt, pulse oximeter, nerve stimulator)
the rate of omission was 25 % or greater.
Fifty patients received local anaesthetic agents
either alone or as part of a combined technique with
general anaesthesia. In approximately 40% of
patients in whom lignocaine was used, the fact was
not documented and in 65 % the concentration used
was not recorded or was inaccurate. Similarly, the
use of a vasoconstrictor was documented poorly, for
adrenaline the concentration being omitted or incorrect in 53%.
In 11 patients a problem occurred with the local
anaesthesia (generally poor block) but was not noted
in nine of these.
The area of the anaesthetic record set aside for
documentation of problems had a low accuracy,
invariably because of data omission. Difficulties with venepuncture (three or more attempts)
were not recorded and difficulties with intubation
(two or more attempts) were recorded in only 45 %
of cases. None of the episodes of hypoxaemia
(observed central cyanosis), vomiting, hypertension
(> 180 mm Hg) or hypotension (< 70 mm Hg) was
recorded.
DISCUSSION
This present study has shown that the inaccuracy of
anaesthetic record text entries is at least as significant
as the inaccuracies in the recording of physiological variables. The most accurate records (other
than basic demographic information) were those
giving details of intraoperative drugs. Few other
records gave less than a 10% rate of omission
or inaccuracy.
Inappropriately
entered (%)
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
The largest number of recording errors related to
data omission, rather than the recording of false
information. Our data indicate that a reviewer, when
examining a completed record, should be most
accepting of entries made and less certain with
regard to the accuracy of absent information.
Analysis of physiological variables recorded manually onto anaesthetic records has demonstrated an
apparent bias towards fewer extreme values and a
smoother physiological course than occurs in reality.
Common explanations given for this bias include
poor memory or the need for retrospective recording
at times of anaesthetic activity (such as during
induction) and the filtering of irrelevant artefact or
physiological fluctuation [5]. It is a widespread
assumption, however, that failure to record physiological variables frequently represents the anaesthetist's defensive attitude towards outside scrutiny
[4]. In this present study, we have observed a high
degree of inaccuracy in anaesthetic record text
entries, the majority of which do not contain
medico-legally sensitive information and which do
not reflect well or badly upon the anaesthetist's
performance. This is consistent with a previous
study [1] in which we found data manipulation of
physiological variables to be uncorrelated with
medico-legal concerns or willingness to use automatic recording devices, but variably correlated with
other factors representing the anaesthetist's attitude
towards the record form's purpose, relevance or
adequacy of design.
One could argue that an anaesthetist's defensiveness is reflected in the low rate of documentation of
morbidity and procedural difficulties. For these
entries, however, the inadequate recording may
simply reflect the lack of formal definition for each
problem. Thus, of those problems and complications
specifically listed, only death could be considered as
sufficiently well denned to require no judgement (or
allow no bias) on the part of the anaesthetist. Other
problems, such as "difficult intubation" or "difficult
i.v. cannulation", lack clear criteria for entry. Lunn
[8] has noted the "folly of a design which permits
mixture of fact with opinion, particularly when
386
subsequent interpretation is anticipated". A
standardized, clearly denned criterion (for example,
in the case of difficult intubation, based on degree of
visualization of the vocal cords) is probably a
necessary requirement for subsequent analysis.
With the obvious exception of drug names, there
are comparatively few differences between records in
current use and those used half a century ago [9,10],
with our modern practice based largely upon "the
traditional and not necessarily logical, nature of our
habits" [11]. In recent years, however, the number
of recordable physiological variables has increased
greatly. Since anaesthetists spend between 10 and
15% [12-15] of intraoperative time completing the
anaesthetic record, it is possible that the added
demands from increased monitoring could further
frustrate the task of accurate record completion.
Given the degree of omission found in these records,
it might also be argued that this time might be better
devoted to direct patient care and that any attempt to
reduce data omission while retaining a manual
recording system would be likely to reduce further
the time spent in patient monitoring. Conversely, it
may be the case that the mental activity required for
manual record keeping prompts patient observation.
A number of authors have suggested that the use
of automated anaesthesia recording devices would
improve the accuracy of anaesthesia documentation
or increase the time spent in direct patient care
[13,16,17]. Others have pointed out the problems
with these devices [18] or have attempted to assess
how these problems could be overcome [19]. However, in addition to accurate, automatically recorded
physiological variables, correct interpretation requires accurate text entries. We have demonstrated
in this study that these text entries are omitted
frequently or are inaccurate, although it is possible
that improvements in this aspect would occur with
computer-based entry [20] and that further improvements in accuracy could be achieved using intelligent
software systems which could reject inconsistencies
and demand a correction at the time of data entry.
While computer-based text entry systems using
keyboard, barcode, light pen, touch screen or voice
recognition have been devised and evaluated
[17,20-23], it is this aspect of automated recording
which has proved the most difficult to implement
and is one reason why completely automated
methods have been slow to develop [11].
Many reasons have been cited for the production
of anaesthetic records, including intraoperative review and trend detection, future patient management, medico-legal documentation, research and
quality assurance. The requirements for each are
different; however, inaccuracy has implications for
all.
Future patient management. Data omission, the
commonest form of text entry inaccuracy could
have serious implications for future patient safety, as
for example in those in whom exposure to halothane
went undocumented. Where patient management is
being planned, the absence of such information
should not be accepted as reliable.
Quality assurance and research. Computer-based
record reviews are undertaken commonly as part of
BRITISH JOURNAL OF ANAESTHESIA
quality assurance procedures and epidemiological
research. It is apparent, however, that only a few text
entry sites can provide accurate data on which to test
research hypotheses or base a quality assurance
analysis. Review of basic demographic features, drug
usage and type of anaesthetic would, on the basis of
our findings, give data of reasonable accuracy and be
useful for monitoring operating theatre utilization
[24,25] and pharmaceutical usage. Quality assurance
review of problems and complications, however,
would collect only a small proportion of those cases
in which problems occurred. When problems are
recorded, these entries are reasonably accurate and,
depending upon the analysis being performed, such
data could be useful. However, comparison of
records documenting a condition with those omitting
such documentation (in order, for example, to
ascertain factors associated with the production of
minor morbidity) would be unlikely to provide data
from which reliable conclusions could be drawn.
Certainly, no reliable comparison could be made
between different anaesthetists' performances, as an
individual's entry criteria differ, as does the diligence
of recording.
Medico-legal documentation. The anaesthetic record has an important role in medico-legal matters,
although it is difficult to imagine how the current
record could provide the basis for an accurate legal
opinion. In this present study, the timing and doses
of drugs were frequently incorrect, as were the fluid
volumes, tourniquet times and site, and the problems
encountered. It is therefore understandable why a
frequent medico-legal problem for anaesthetists is
the inaccuracy of their anaesthetic record. Powers
and Gore noted with regard to intraoperative
problems that their "improper and inadequate...
notation... will require explanation and might even
make certain cases legally indefensible" [26]. Dillon
noted in regard to malpractice claims that records
"almost always are grossly incomplete" [27].
In summary, this study has shown major inaccuracies in the text entries of manually compiled
anaesthetic records. In conjunction with many
studies which have demonstrated inaccuracy in the
entry of physiological variables, we conclude that the
manual record may present future anaesthetists with
misleading information which could detrimentally
affect patient safety. Although an anaesthetist may
be reasonably (although not completely) confident
that an event occurred if it is documented, he/she
should not entertain such confidence if an event is
not documented.
A previous record does not provide the anaesthetist with a reliable summary of preoperative
condition, drug allergy or medications. Most importantly, the absence of recordings related to
difficulty of intubation and exposure to halothane
need to be viewed with considerable caution.
ACKNOWLEDGEMENTS
This study was part of a project supported by the New Zealand
Medical Education Trust (Grant 159). The authors wish to thank
Mr Chris Gousmett for his help in the conduct and analysis of this
study.
ACCURACY OF ANAESTHETIC RECORDS
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