Download N Gokal Counting the Costs

24 August 2012
No. 28
Counting the Costs
N Gokal
Commentator: SM Roberts
Department of Anaesthetics
Moderator: G Allopi
CONTENTS
INTRODUCTION: ....................................................................................... 2
CONTEXT: COST CONSCIOUSNESS AMONG ANAESTHETIC STAFF . 2
COUNTING THE COST OF THEATER TIME............................................. 3
Direct and indirect costs ....................................................................... 3
Staff in theater ........................................................................................ 4
Pharmacoeconomics ............................................................................. 5
Anaesthetic Drug Costs in Context ............................................................. 5
Route of administration: Injectable verses inhaled ................................... 6
Premedication ............................................................................................... 6
Anaesthetic Induction ................................................................................... 7
Anaesthetic Maintenance ........................................................................... 11
The Use of Generic Drugs .......................................................................... 18
RECOMMENDATIONS ............................................................................ 20
CONCLUSION.......................................................................................... 20
APPENDIX ............................................................................................... 21
REFERENCES ......................................................................................... 24
1
INTRODUCTION
Over the past few years, health care “reform" has resulted in funding
cutbacks in many aspects of healthcare. The ever increasing patient
load has exposed inadequacies in the allocation of the national budget.
Hospitals have struggled to cope with this demand. The medical
practitioner has seen a decrease in the number of available treatment
options as the void between public and private care continues to
increase unrelentingly.
The pharmacy budget, which accounts for 4-8% of total budgets in most
hospitals (1), has been identified as an area for cost-cutting. Anaesthetic
drugs represent a relatively small proportion of this component
(approximately 5-10%), cost-minimization strategies, including
substitutions and restrictions on certain drugs, and the introduction of
educational programs, have all been implemented with varying degrees
of success. (1) Although these programs might seem appealing in their
potential for cost cutting, their effectiveness is extremely difficult to
evaluate.
Value-based anaesthesia, refers to delivery of the best possible care at
a reasonable cost. (3)
CONTEXT: COST CONSCIOUSNESS AMONG ANAESTHETIC STAFF
The current economic climate has placed pressure on the anaesthetist
to add cost as an anaesthetic consideration in every case. At the
forefront of every practitioners mind needs to be the question: “does the
benefit obtained from a particular intervention justify the cost of the
intervention.” Obviously to be able to answer this question a prerequisite
is knowledge of the costs involved. Once this pre request is in place
excessive costs and waste can be minimized while maintaining
standards of patient care and safety.
A study carried out in Denmark looked at cost consciousness among
anaesthetic staff. They demonstrated that 38% of all estimated costs
were within 50% of the actual costs and 85% were within 100% (6). From
this they concluded that the overall consciousness of anaesthetic agents
among staff was clearly deficient.
2
COUNTING THE COST OF THEATER TIME
Direct and indirect costs
There are numerous costs associated with delivery of an anaesthetic.
These costs are difficult to measure accurately. However, they need to
be taken into account in order to make reliable comparisons between
one drug or technique with another.
These costs can be broadly classified as direct and indirect costs. Direct
costs include the price of the anaesthetic drugs themselves, but also
include the cost attached to delivery of the agent. Indirect costs
represent the consequences of administering a given anaesthetic and
therefore include the cost of delayed recovery and treatment of adverse
effects. Indirect costs are notoriously difficult to measure, such as those
associated with improved patient satisfaction. In addition, costs may
have a fixed component; these costs are incurred irrespective of the
numbers of patients treated, and a variable component which changes
with the number of anaesthetics administered and/or their duration. (7)
Direct costs
In many private institutions, the price the patient is charged for drugs is
readily available. However, this charge is subjected to a substantial
mark-up, designed to generate profit and to cover other costs
(overheads) which cannot be directly billed for.
There is a loose relationship between drug acquisition cost and patient
charge (8) and cannot be used when determining costs. The
manufacturer’s recommended price is commonly used for comparisons
between drugs. Prices change over time, so it is imperative to use an up
to-date reference source. The price that a hospital pays is most often
less than the recommended price. The extent of the discount is subject
to negotiation between the hospital and the pharmaceutical company,
and will vary depending the quantity purchased, the number of additional
products bought from the same supplier, the prestige of the institution,
etc.
The purchase price is also influenced by patent protection. While a
single supplier is less likely to offer a significant discount, competition
between suppliers benefits the hospital as it effectively drives prices
down considerably.
3
Drug acquisition costs vary from country to country. For this reason,
studies looking at pharmacoeconomics in other countries may not
always be relevant in our setting. Not only does the direct cost of drugs
differ internationally, but the indirect costs of different drugs may also
vary between populations.
Variation may exist between formulation of drugs, as well as differences
in the package quantity, between countries. Finally, patent protection will
be lost at different times throughout the world so that one country may
have access to inexpensive generics while others have to pay the full
price for the branded product.
Indirect costs:
Indirect costs are those costs associated with consequences of a
particular treatment. Examples would include adverse effects such as
postoperative nausea and vomiting (PONV), unanticipated hospital
admission, prolonged recovery or hospital stay and time away from
work. Costs due to adverse effects may include drugs as well as staff
costs.
Again, these will have fixed and variable components. Some indirect
costs, such as lost productivity or lost earnings, may be borne by society
as a whole or by the patient. These may well be significant, but may be
of less concern to the hospital. There will also be a related cost
associated with patient discomfort or well-being, but this is very difficult
to quantify.
Staff in theater
‘Time is money’ which is no less true than for operating theater time.
Delayed recovery results in increase operating room time. The extent of
which depends on how the staff are paid and employed. With part time
staff, paid on an hourly basis, costs will be approximately proportional to
workload, since these staff will not be paid unless there is work to do.
However, in our setting nursing staff earn salaries.
This means that they are paid to work a fixed number of hours,
irrespective of the work intensity. Small changes in workload will have no
cost implications, since the staffs are there irrespective. Larger changes
in workload will have an effect, only if they alter the number of staff
required for a shift or vary the requirement for paid overtime.
4
Dexter et al (9) used mathematical modeling to examine how faster
emergence from anaesthesia affected operating and recovery room
time.
For part-time staff (who were paid per hour worked) savings were
directly related to the time gained. However, this relationship could not
be demonstrated with small changes in recovery times, amounting to a
few minutes. The reason for this was that time keeping systems were not
sensitive enough to detect small changes. Another explanation which
was offered was that the nursing team is often required to perform a
number of tasks before the next case can begin; In which case a
reduction in recovery time may still not fast track the next patient on a
list.
In the case of salaried staff, Dexter et al (9) found that the only way to
make a saving would be to employ less staff and therefore reducing the
time spent in the operating room would have no effect on staff costs. He
found that this could only be achieved by drastic measures, such as
increasing the proportion of patients bypassing the phase I recovery
room by about 20%, this would achieve a saving of one full-time salary,
amounting to a saving in the region of $US6 per case. (8) Variations in
workload may have other effects as well. Delayed recovery may block
the operating theater and the recovery room. Such delays could
potentially result in cancellation additional days of hospital admission
and delayed discharge from hospital. (8)
Pharmacoeconomics
Table I Acquisition Costs of drugs used in anaesthesia
Replacing given drug for a cheaper agent doesn’t always result in cost
reduction as it doesn’t take into account how anaesthetics are delivered,
the quality of care, and the impact of different drugs on various outcome
factors. Often the more expensive agent saves money overall, however
this is not always the case and determining the total cost associated with
a given agent is challenging and fraught with difficulty.
5
Anaesthetic Drug Costs in Context
Before considering the costs associated with anaesthetic drugs, it is
important to place these in context. Anaesthetic drugs account for
approximately 3-4% of the cost of a surgical procedure. (10) For a
common day case procedure, such as laparoscopic sterilization, surgical
disposables cost 4.5 times as much as anaesthetic drugs. (10) Perhaps
the most substantial part of perioperative costs is comprised of staff
wages, including those of anaesthetists, surgeons and nurses in the
operating theatre and recovery area.
These components have a far greater impact on overall costs than drug
choice alone. However the choice of drug may significantly impact on
duration of hospital admission.
Route of administration: Injectable verses inhaled
Intravenous Anaesthetics
Certain drugs are administered in fixed quantities, e.g. a tablet or a
whole ampoule, the amount used is obvious. The direct cost in this case
will be the product of the unit cost and the number of doses
administered. The situation is less straight forward when it comes to
drugs which are administered in variable quantities, as is the case with
majority of anaesthetic drugs.
Often a single ampule will be divided for use between cases especially
common practice in paediatric anaesthesia and where the case turnover
is high. The disadvantage of such practice is the risk of infection with
propofol and the time that the ampule is opened must be noted. Once
opened it provides an excellent medium for pathogen growth. Never the
less, this is quite common practice and may significantly affect direct
drug costs complicating the calculation of direct costs of intravenous
anaesthetics.
Premedication
The thought of surgery instills feelings of fear and anxiety, therefore the
preoperative use of an amnestic/anxiolytic (e.g. midazolam or diazepam)
may be beneficial.
Although the cost of midazolam exceeds that of diazepam (table I), the
shorter terminal half-life of midazolam (2 to 3 hours versus 12 to 18
hours) means that it minimally delays postoperative awakening.
Midazolam also functions synergistically with propofol, thereby
decreasing the need for (and cost of) propofol.
6
However, not all patients require pharmacological anxiolysis, time taken
to reassure a patient and address any uncertainly is often regarded as
being superior to pharmacological anxiolysis. Thus avoiding the use of
midazolam decreases drug cost and, perhaps, time for recovery.
Anaesthetic Induction
Induction agents:
Induction of anaesthesia may be achieved in one of two ways. Either by
injection of one or more drugs or by delivery of inhaled anaesthetics.
Despite the greater cost of propofol, several desirable attributes have
caused it to gain favor over barbiturates especially for day-case surgery.
These include: (i) retrograde amnesia; (ii) antiemetic property; and (iii) a
rapid redistribution and greater vulnerability to metabolism, and thus less
‘hangover’ after anaesthesia (10).
Opioids
Fentanyl is the most commonly given opioid for induction, other opioids
are reserved for cases were more stringent haemodynamic control is
needed. The dose is tailored to suppress cardiovascular responses to
stimuli such as tracheal intubation and surgery without delaying
recovery. Thus, the practitioner may choose a shorter-acting, but more
expensive, opioid such as alfentanil or remifentanil. Because its halflife is <10 minutes,remifentanil has many advantages over other opioids
and is the the drug of choice if precise ‘moment-to-moment’ control is
desired.
Its context sensitive half life is independent of the duration of the
infusion. However, remifentanil is an expensive opioid. Its use typically
mandates a continuous infusion pump which takes time to set up and its
use has been associated with opioid induced hyperalgesia. Because its
actions short lived, its use may result in significantly increased
postoperative pain scores.
Although inexpensive, pethidine (meperidine) and morphine are rarely
used during induction. The use of pethidine has fallen out of favor in
recent times. It was recently believed that Perthidine has less of an
association with PONV than morphine but studies demonstrating this
used inequivalent doses. It was also belived to cause less Sphincter of
Oddi spasm but this has also been disproven by randomized trials.
It is less potent than morphine and causes the same amount of
histamine release. Its only advantage lies in the 25 mg dose used in the
treatment of post-operative shivering. All opioids can increase the
incidence of postoperative nausea and vomiting.
7
Muscle relaxants:
A number of factors are taken into account when choosing an
appropriate muscle relaxant. If relaxation is only needed for
endotracheal intubation alone (i.e. for a brief period), then a common
choice in adults is the depolarising relaxant suxamethonium
(succinylcholine).Suxamethonium is inexpensive and produces paralysis
in the shortest time.[30] An intubation using sux as a muscle relaxant
may lessen delay by 1 to 3 minutes.
This may seem like a trivial delay but when you consider that the cost of
operating room time in a study conducted in the United States was
shown to be between $US10 to $US20 per minute. (10) Unfortunately
such a study has never been reproduced in our setting. Results would
certainly be beneficial.
But suxamethonium may impose other ‘costs’. Particularly pertinent is its
capacity to produce postoperative muscle pain. In addition,
suxamethonium
may
cause
rhabdomyolysis
and
malignant
hyperthermia. Sux therefore serves as an example of how indirect costs
can supersede direct savings.
The nondepolarising relaxant rocuronium bromide rapidly induces
paralysis without producing postoperative muscle pain.
But rocuronium is more expensive and lasts far longer than
suxamethonium or another nondepolarising, equally expensive, relaxant,
mivacurium chloride. Rocuronium is more useful if relaxation is required
for surgery as well as for intubation. Mivacurium is a shorter acting
nondepolarising relaxant – but its onset is not rapid, nor do conventional
doses consistently produce good conditions for tracheal intubation.
Older relaxants such as pancuronium bromide (table I: Pancuronium
2mg/ml 2ml R4.38) may be a lot cheaper than newer agents like
rocuronium (50mg/5ml 5ml R41.39). But this is another example of how
the indirect saving supersedes the direct cost as rocuronium has been
shown to significantly shortern operating room times and PACU times.
(16)
Minimum alveolar concentration (MAC) reflects potency of inhaled
agents required to eliminate movement in 50% of patients in response to
a noxious stimulus such as a surgical incision. MAC is an anaesthetic
50% effective dose (ED50) that defines potency for all inhaled
anaesthetics. Immobility in 95 to 100% of patients requires anaesthetic
concentrations 10 to 30% greater than MAC.
8
Table I: Clinical and Economic Factors Important to Anaesthetic Choice for Day-Case Surgery Edmond
I. Eger, Paul F. White and Martin S. Bogetz
Halothane and sevoflurane are commonly used to induce anaesthesia in
children and, occasionally, in adults, particularly for brief procedures
(fig. 1).
Fig 1 sevoflurane tends to be used for
shorter procedures (in some patients purely for induction of anaesthesia).
Isoflurane tends to be used for longer procedures, whereas desflurane is used for both.
Clinical and Economic Factors Important to Anaesthetic Choice for Day-Case Surgery Edmond I.
Eger, Paul F. White and Martin S. Bogetz
9
Halothane and sevoflurane are minimally pungent and produce less
breath holding, coughing or laryngospasm. Trials in children, comparing
Sevoflurane and Halothane demonstrated that times to induction differ
by only a few seconds (fig. 2).
Fig 2 The median (± quartiles) time to induction of anaesthesia in children
Clinical and Economic Factors Important to Anaesthetic Choice for Day-Case Surgery
Edmond I. Eger, Paul F. White and Martin S. Bogetz
Differences depend on the relative delivered concentrations. At inspired
concentrations that cause equal MACs, sevoflurane produces a more
rapid induction; however, at the maximum settings of present vaporizers
(5% halothane, 8% sevoflurane), times to intubation of the trachea are
clinically indistinguishable (fig. 2).
The 2 anaesthetics did not differ in a double-blind test of speed and
quality of induction. [52] Despite its greater acquisition cost (table I),
some considerations suggest the use of sevoflurane rather than
halothane. Patients given sevoflurane have fewer ventricular
extrasystoles and may awaken sooner. Although hepatic injury
(increased hepatic transaminases) may follow sevoflurane anaesthesia
(a causal relationship has not been established), sevoflurane rarely (if
ever) causes the severe hepatic injury associated with halothane,
particularly in adults.
10
Anaesthetic Maintenance
Anaesthesia may be maintained with injected agents alone, by inhaled
anaesthetics alone, or by combinations of injected and inhaled
compounds. These approaches are all acceptable however they differ in
their clinical and economic implications. The most commonly used
agents to maintain anaesthesia remains potent inhaled anaesthetics (fig.
3) with nitrous oxide.
Fig 3 Clinical and Economic Factors Important to Anaesthetic Choice for Day-Case Surgery
Edmond I. Eger, Paul F. White and Martin S. Bogetz
The primary anaesthetics used in the US in 1998 to maintain general anaesthesia
Total Intravenous Anaesthesia
Total intravenous
anaesthesia (TIVA) requires
similtainious
administration of a number of agents. Propofol effectively causes
sedation, amnesia and even immobility, but not analgesia or muscle
relaxation. TIVA is supplemented with opioid analgesics, usually as an
infusion, and muscle relaxants.
11
In fact ‘TIVA’ often includes administration of nitrous oxide, since nitrous
oxide neither decreases blood pressure nor delays recovery, and may
be used to decrease the requirement for the more expensive
intravenous drugs. However TCI uses algorithms based on populations
studies of patients not receiving nitrious oxide and therefore the
introduction of nitrious oxide will not change the rate of infusion and the
quantity of intravenious agent used will not change. In other words
nitrious oxide does not carry an economic benefit even though it might
be effective.
This forms an aid to guide infusion rates possibly reducing rates of
infusion and the amount of agent used. The proposed advantages of the
BIS monitor is that it considers the combined sedative effects of
depressant drugs (e.g. midazolam, propofol and inhaled anaesthetics).
BIS monitor use may decrease propofol and may decrease time to
awakening.
The draw back to the monitor is the cost of the monitor itself and the
disposable electrodes. In addition, it reflects population averages for
sedation, whereas individual propofol concentrations at a given BIS
value vary by factors of 4 or more among different patients. Finally, the
monitor reading may not equally reflect the level of sedation for different
drugs or conditions. For example, patients having anaesthesia for
trauma surgery may recall information at BIS levels that nominally
suppress such recall. Thus, the BIS monitor provides a rough, not a
precise, guide, and it cannot guarantee the absence of awareness.
Inhaled Anaesthetics
The vaporizer provides a reservoir of anaesthetic which, unlike
intravenous agents, may be used from patient to patient without risk of
infection. However, only a portion of delivered anaesthetic vapor
reaches the alveolus and is absorbed. If vapor remaining in expired gas
is vented to the atmosphere, it is wasted. Older studies found as much
as a 70% decrease in enflurane consumption by reducing the fresh gas
flow from 6 to 1 L/min over 1 hour, (12) amounting to a considerable cost
saving. Similarly, isoflurane consumption was reduced by 81% by
changing from high gas flows (≥4 L/min)to low flows (0.6 to 0.7 L/min).
(12) Even in children, low-flow anaesthesia may produce considerable
savings.
Use of a circle system reduced average gas flows from 2.6 to 1.2 L/min,
lowering isoflurane consumption by 58%. (12)Low-flow anaesthesia has
the considerable advantage of reducing costs without compromising
12
outcome or patient safety. (14) An education program which informed
anaesthetists of their average fresh gas flow rates in relation to the peer
group mean and advised flow reductions resulted in a 26% reduction in
fresh gas flow from 2.4 ± 1.1 to 1.8 ± 1.0L/min. (15) In the absence of
continued feedback, fresh gas flows had increased after 5 months, but
were still below the original values. Despite advice to the contrary, the
use of more expensive, less soluble anaesthetics actually increased.
The belief that low-flow anaesthesia was more controllable with such
agents was a possible explanation for this.
Inhaled anaesthetics have vastly different acquisition costs as evident in
table I. Their solubility and potencies also differ which reflects in their
partition co efficients and their MAC. (10) These properties influence cost
as a higher MAC and solubility (table II) increase anaesthetic use.
Because at a given concentration a smaller mass of a less soluble
anaesthetic is absorbed during induction, induction can be achieved
more quickly and by delivery of a lower mass of drug. This is because an
insoluble gas has a higher alveolar partial pressure and therefore a
higher partial pressure in the blood. MAC and solubility tend to vary
inversely, producing a rough economic balance.
This is because MAC or potency is dependent on lipid solubility. For
example, a lower solubility partially compensates for the greater usage
associated with the higher MAC of desflurane versus sevoflurane.
Sevoflurane is less soluble in blood than agents like halothane and
isoflurane.
This means that the rate of induction is faster than either of these
agents. However both halothane and isoflurane are more potent than
sevoflurane and therefore a larger amount needs to be used to maintain
the anaesthetic. (17) This confirms the fact that Sevoflurane is an
excellent agent for induction but does not carry a cost benefit if used for
maintenance. It therefore makes economic sense to change over from
sevo to iso after induction. (2)
Solubility also influences the rate at which concentration can be
changed. Due to this difference in solubility haemodynamic control may
be achieved more readily with desflurane at low gas flow rates, this has
a bearing on cost. Anaesthetic solubility also influences cost, because
solubility is an important factor in elimination of inhaled anaesthetics,
and thus to emergence from anaesthesia. (18) awakening is more rapid
after desflurane than after sevoflurane anaesthesia, and more rapid after
sevoflurane than after isoflurane anaesthesia.
13
Evidence has shown that Desflurane anaesthesia produces quicker
discharge from the PACU than isoflurane or halothane anaesthesia. (1922)This correlation is especially true for elderly patients, (22) or after
prolonged anaesthesia. (24)
Fig 4 Recovery after approximately 5 hours of comparable levels of anaesthesia
Beaussier M, Deriaz H, Abdelhim Z, et al. Comparative effects of desflurane and isoflurane on
recovery after long lasting anaesthesia. Can J Anaesth 1998
This relationship could not be reproduced whenEbert TJ, Robinson BJ,
Uhrich TD, et al compared Sevoflurane to Isoflurane (25).
14
Fig 5 Recovery after 3 to 5 hours of comparable levels of anaesthesia
Ebert TJ, Robinson BJ, Uhrich TD, et al. Recovery from sevoflurane anesthesia.A comparison to
isoflurane and propofol anesthesia. Anesthesiology
Awakening in the 30 to 60 minutes immediately after anaesthesia is
usually more rapid after desflurane anaesthesia than after sevoflurane
anaesthesia. (26-27) time to discharge may not differ, unless fasttracking is employed.
The use of gas analysis imparts an economic benefit as precise levels
can be targeted based on a measured value rather than a calculated
value. Concentrations can be adjusted in order to match patient
demands.
Low flow anaesthesia:
Liquid anaesthetics such as sevoflurane or desflurane are converted to
gases and then diluted and delivered to the anaesthetic circuit which
allows rebreathing of these gases after absorption of CO2. Rebreathing
is essential to an economical delivery of anaesthesia. A high gas flow is
used to establish the concentration needed for induction of anaesthesia.
To reduce anaesthetic waste and cost, flow is decreased and
rebreathing increased during maintenance of anaesthesia.
15
A shorter period of high flow may be needed to establish a stable level of
anaesthesia with a less soluble inhaled anaesthetic (table II). (28) A need
to economize has caused inflow rates to decrease.
Flow rates of 1 L/min or less are increasingly common, with one
exception related to the potential nephrotoxicity of sevoflurane The
presently distributed package labeling of sevoflurane in the US (but not
in South Africa) warns that sevoflurane should be used at inflow rates of
2 L/min or greater. An updated version of the package labeling allows an
inflow rate of 1 L/min for up to 2 hours at 1 MAC, but recommends
imposition of sevoflurane at this concentration for no longer time
because of the concern regarding nephrotoxicity.
Thus limiting the economy potentially available with Sevoflurane.
Studies which aim to determine cost efficiency of Sevoflurane over other
volatiles use inequvalent flow rates due to the concern of nephrotoxicity.
This concern is purely theoretical and has not been demonstrated
clinically.
Despite the lower acquisition costs of sevoflurane compared to
desflurane studies have shown that sevo actually has a higher cost due
to the higher flow rate.
The isoflurane cost per patient is less than that for either desflurane or
sevoflurane (Table I). However, recovery after isoflurane anaesthesia is
delayed(Fig. 4, Fig 5)owing to its higher solubility as reflected by its
higher blood gas partition go efficient (Table II)
Costs of TIVA generally exceed those associated with potent inhaled
anaesthetics, equaling $US10 to $US50 (1999 values) per hour more
depending on the combination of agents used.
Maintenance of anaesthesia with 1 MAC isoflurane at a flow rate of 1
L/min costs approximately $US1 per hour, whereas thecost for
desflurane at 1 MAC is $US6 per hour, and sevoflurane at 1 MAC at a
flow rate of 2 L/min costs $US14 per hour.(29) Anaesthesia with isoflurane
may result in a lower net cost than anaesthesia with sevoflurane.
Concurrent nitrous oxide administration may decrease maintenance
costs by a factor of 2 because nitrous oxide is inexpensive and
significantly decreases the requirement for volatile anaesthetic as
described by the concentration effect. (17) Inhalational agents potentiate,
and thus decreasing the use of non-depolarizing muscle relaxants. (10,17).
Combination or ‘Balanced’ Techniques
16
Both inhalational and intravenous anaesthesia have advantages.
‘Balanced’ Techniques aim to combine these advantages. For example,
premedicate with lorazepam 1 to 2mg, induce anaesthesia with propofol
plus fentanyl, provide muscle relaxation with suxamethonium or one of
the intermediate- duration relaxants (atracurium, cisatracurium,
mivacurium, rocuronium or vecuronium) and maintain anaesthesia with
nitrous oxide plus a potent inhaled anaesthetic (desflurane, isoflurane,
sevoflurane) or propofol infusion.
Midazolam is preferred to diazepam because of its more rapid onset of
action and also provides shorter lasting amnesia. Propofol is preferred to
thiopental because it produces less ‘hangover’. Relative to propofol,
thiopental may delay recovery and discharge. (17) Fentanyl can decrease
pulse rate and thereby decrease cardiac work, and ‘standard’ (1 to 4
mg/kg) doses of fentanyl does not delay awakening. However, because
of its context sensitive half-life, fentanyl cannot be used as an infusion.
Nitrous oxide is frequently used because of its minimal cost, its
analgesic properties and its rapid elimination.A50% concentration of
nitrous oxide may be preferred because it decreases the MAC because
greater concentrations may increase the incidence of emesis. Because
of the frequent use of LMAs to secure the air- way, a muscle relaxant
may not be needed for many day-case surgeries. If needed, the choice
of relaxant depends on the duration of paralysis required. Several
factors govern the choice of a potent inhaled anaesthetic.
As indicated in table I, halothane and isoflurane have lower acquisition
costs than desflurane and sevoflurane. If speed of anaesthetic
elimination is of no concern, then these less expensive anaesthetics
may be selected. The nonpungent anaesthetic, halothane, may be
preferred if irritation of the respiratory tract is a concern. However, unlike
the alkane halothane, the ethers, isoflurane and sevoflurane do not
predispose the heart to arrhythmias, and their potential for hepatic injury
is much smaller.
If the most rapid rate of recovery is needed, then desflurane or
sevoflurane may be considered.
17
Fig 6: Cost ($US, 1998 values) per patient to maintain anaesthesiain the US.
Hospital Research Associates Anaesthesia Audit (Syndicated Study). Fairfield (NJ): Hospital Research
Associates
Despite lower acquisition costs in the US, the present cost of desflurane
per patient is half that of sevoflurane (fig. 6), primarily because higher
inflow rates are used with sevoflurane to minimize the risk of renal injury.
This is a study that has never been reproduced in our setting. The
results are expected to be vastly different as Ultane does not carry the
same warning as the sevoflurane used in the US and is used at much
lower flow rates in South Africa. Recovery is faster with desflurane, and
there may be less toxicity concerns.
Emergence delirium may occur after anaesthesia with desflurane,
sevoflurane or other potent inhaled anaesthetics, particularly in children
<5 years of age. (17) This effect may delay discharge from recovery
areas. It may be prevented by administration of fentanyl 2 to 3mg/kg.
The Use of Generic Drugs
The role of the US Food And Drug Administration (FDA) Center for Drug
Evaluation and Research (CDER) is to ensure that drugs marketed in
the country are safe and effective.
18
CDER does not test drugs, although the Center's Office of Testing and
Research does conduct limited research in the areas of drug quality,
safety, and effectiveness.
When companies submit a new drug application to introduce a new drug
product into the U.S, it is the responsibility of the company seeking to
test it and submit evidence that it is safe and effective. A team of CDER
physicians, statisticians, chemists, pharmacologists, and other scientists
review this data.
A generic drug product is one that is comparable to an innovator drug
product in dosage form, strength, route of administration, quality,
performance characteristics and intended use. Generic drug applications
are generally not required to include animal and human data to establish
safety and effectiveness. Instead, generic applicants must scientifically
demonstrate that their product is bioequivalent (i.e., performs in the
same manner as the innovator drug).
One way scientists demonstrate bioequivalence is to measure the time it
takes the generic drug to reach the bloodstream in healthy, volunteers.
This gives them the rate of absorption, or bioavailability, of the generic
drug, which they can then compare to that of the innovator drug. The
generic version must deliver the same amount of active ingredients into
a patient's bloodstream in the same amount of time as the innovator
drug.
No specific mention is made to: Side effects, preservative ingredients,
facility in which the drug is manufactured or the clinical effectiveness of
the drug. (30)
Is the generic equivalent to the original, predecessor, drug?
19
RECOMMENDATIONS
I.
II.
III.
IV.
V.
VI.
VII.
Display price lists in every theater, and update these lists on a
regular basis
Costing feedback meetings
Choice of anaesthetic gas
Choice of flow rates
Generic drugs
PONV
IV Fluids (does every case need IV fluids running/does IV access
just suffice)
CONCLUSION
Drug costs are easy to measure and are often the target for restriction to
achieve cost reduction. This approach is short sighted and recommendations
fail to take into account indirect advantages of using seemingly more
expensive agents. The evidence supporting the use of such agents is limited
and when available not relevant to our setting. The current economic climate
has led to cost awareness becoming a significant anaesthetic consideration.
Limiting the use of high profile drugs to areas in which they have a clear
clinical benefit, through ‘educational’ programs and practice guidelines, can
produce savings of 23 to 43%. (5) The effect of such a strategy may be shortlived, however, (5) emphasizing the need for continued re enforcement. This
evidence suggests that practitioners are willing to change their practice in the
name of cost reduction. Quantifying indirect costs remains a major challenge.
The goals should be clear and include, shorter hospital stays less postoperative complications and quicker transit through PACU and theaters
without compromising on patient safety. What is also clear is that minimizing
waste is beneficial in cost saving.
Lowering fresh gas flows with inhaled anaesthetics (28) not drawing up
intravenous drugs until they are about to be used and limiting the number of
syringes used per patient will reduce drug costs without any impact on
outcome. Other sources of waste include surgical disposables, time lost
through cancellations and misdiagnoses, improperly prepared patients,
excessive cleaning between cases and missing staff. The temptation is to
focus on easily measured drug costs while ignoring other major costs and
sources of waste, in other words being ‘penny wise, but pound foolish’.
20
APPENDIX
Drug and Classification
Benzodiazepines
Midazolam
Midazolam
Lorazapam
Diazepam
Diazepam
Induction Agents
Thiopentone
Propofol
Propofol
Etomidate
Ketamine
Ketamine
Ketamine
Volatiles
Isoflurane
Halothane
Sevoflurane
Desflurane
Enflurane
Analgesia: Opioids
Morphine
Morphine
Pethidine
Preparation
Price
5mg/ml 5ml
5mg/ml 3ml
1mg tablets 100’s
5mg/ml 2ml
5mg tablets 500’s
R5,15
R4.87
R 78.32
R1.66
R33.32
0.5g/20ml
10mg/ml 20ml
10mg/ml 50ml
2mg/ml 10ml
10mg/ml 10ml
50mg/ml 10ml
100mg/ml 10ml
R17.74
R8.30
R47.19
R50.03
R29.07
R36.98
R75.66
250ml
250ml
250ml
240ml
250ml
R202.42
R324.30
R1047.90
R1296.14
R515,91
10mg/ml
15 mg/ml
25mg/ml
R1.33
R 1.40
R 1.98
Fentanyl
Fentanyl
Alfentanil
Sufentanil
Sufentanil
Remifentanil
Remifentanil
Remifentanil
Alternative
Tramadol
Ketorolac
Ketorolac
Paracetamol oral
Paracetamol IV
Opioid reversal
50mcg/ml 2ml
50mcg/ml 10ml
0.544mg/ml 2ml
5mcg/ml 2ml
5mcg/ml 10ml
1mg in 3ml vial
2mg in 5ml vial
5mg in 10ml vial
R1.53
R4.30
R35.94
R13.17
R79.24
R90.63
R81.90
R464.19
50mg 100’s
10mg/ml 1ml
30mg/ml 1ml
500mg 100’s
1g/100ml
R22.62
R17.64
R30.01
R7.86
R38.30
21
Niloxone
Naloxone
Muscle relaxants
Suxamethonium
Atracurium
Atracurium
Cisatracurium
Cisatracurium
Cisatracurium
Rocuronium
Pancuronium
Vecuronium
Mivacurium
Reversal Agents
Glycopyrralate
Neostigmine
Neostigmine
Antiemetics
Droperidol
Metoclopramide
Ondansetron
Ondansetron
Dexamethasone
Other Drugs
Atropine
Adrenaline
Dopamine
Dantrolene
0.4mg/ml 1ml
0.02mg/ml 2ml
R2.41
R4.21
50mg/ml 2ml
10mg/ml 2.5ml
10mg/ml 5ml
2mg/ml 2.5ml
2mg/ml 5ml
2mg/ml 30ml
50mg/5ml 5ml
2mg/ml 2ml
4mg Powder
2mg/ml 5ml
R2.14
R39.90
R52.24
R30.69
R42.00
R399.68
R41.39
R4.38
R15.45
R39.50
0.2mg/ml 2ml
0.5 mg/ml 1ml
2.5mg/ml 1ml
R9.79
R6.59
R1.83
2.5mg/ml 2ml
5mg/ml 2ml
4mg/2ml 2ml
8mg/4ml 4ml
4mg/ml
R42.97
R1.26
R6.37
R9.03
R3.73
0.5mg/ml
1mg/ml
40mg/ml 5ml
20mg
R1.72
R1.68
R3.02
R1527.75
Dobutamine
EphidrineSulphate
Phenylephrine
12.5mg/ml 20ml
50mg/ml 1ml
10mg/ml 1ml
R21.31
R31.45
R27.95
Local Anaesthetics
Lignicaine 1%
Lignocaine 2%
20ml vial
5ml IV use
R 5.38
R2.38
5mg/ml 10ml
5mg/ml 4ml
5mg/ml 20ml
5mg/ml 5ml
R3.28
R10.76
R16.64
R3.64
Bupivacaine
Bupivacaine
Bupivacaine with adrenaline
Bupivacaine with dextrose
Blood Products and Services
22
Levy: After hours
Levy: Blood on returnable basis
Levy: Emergency blood surcharge
Levy: Emergency cross-match
Platelet concentrate - Pooled
Platelet concentrate (Paediatric)
Red cell conc. Pead - Leucodepl
Red cell conc. (in additive soln)
Red cell conc - Leucocyte depleted
Transfusion crossmatch
Type and screen
Whole blood – Leucocyte depleted
R307,90
R120,63
R136,95
R114,81
R5 769,40
R1 741,18
R1 265,57
R1 369,39
R2 237,52
R609,33
R272,83
R2 384,66
Table I Values obtained from Inkosi Albert Luthuli Central Hospital Pharmacy August 2012
23
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