Pediatric Sedation Newsletter – April 2004 by WesleyL

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									            Pediatric Sedation Newsletter – April 2004
Departments of Anesthesiology and Pediatrics, Children’s Hospital at Dartmouth, Dartmouth
Hitchcock Medical Center, Lebanon, NH
Editors: Joseph Cravero MD (joseph.cravero@hitchcock.org),
George Blike MD george.blike@hitchcock.org
Website = http://an.hitchcock.org/PediSedation/
Circulation 3425

Sedation Conference: There was an error concerning the program of events on the website
announcing the First International Multi-specialty Sedation Conference. The meeting will take
place on the 22nd of May, Saturday. This will include lectures, lunch time question and answer
session, and afternoon break-out sessions. There will be an informational meeting about the
Pediatric Sedation Research Consortium on Sunday the 23rd of May for any interested parties.
An organizational meeting for current PSRC members is planned for Friday the 21st. Please look
for details at http://www.thechildrenshospital.org/pro/cs/detail.cfm?RecordID=1195

Reprints: In case you were wondering…… in the past we have reprinted editorials and
commentaries from various journals in their entirety here in the Newsletter after obtaining
permission. After seeking approval from various journals to do this more recently we have been
“discouraged” to continue. In the true spirit of the internet, we will just shift our strategy and
hopefully deliver the same product without getting into trouble. Instead of reprinting an entire
editorial, we will try to summarize the major points and issues raised, and point you to the full
text reference.

Mailbox: We had a letter from a reader recently which raised an interesting point and we seek
other opinions on this matter.

I have a question which maybe we can bring up with the consortium. Recently,
it has been discussed if a follow up phone call should be made the day after
all procedural sedations. Currently this is done by our outpatient surgery
center and radiology. The phone call entails asking if there were any
problems the family or child experienced. According to the radiology nurses
they rarely if ever discover an adverse event. Is this a process which is done at other
institutions?
Should this be a standard of care?

Jill Fitch MD – Columbus Children’s Hospital

   At Dartmouth we make a pre-sedation phone call to all patients. Like most institutions we
seek to gain information on the child in terms of medical history, previous experience etc., and to
give NPO guidance as well as answer any specific questions that families have about the
sedation itself. Although our Same Day Surgery section makes a call to all patients post-
operatively – we do not make such a call to all sedation patients. Our nursing and physician
providers do call any patients who were particularly worrisome in some way (i.e. had a lot of
delirium on emergence) but this is not routine.
     We can imagine a lot of arguments in favor of such a practice. Clearly, many children who
receive sedation are not “back to normal” for a long time after their procedures. Malviya and
colleagues (Pediatrics 105 (3) E42, 2000) described prolonged effects of long-acting sedatives in
a cohort of pediatric sedation patients several years ago. Contacting these families routinely
might help them avoid a trip to the emergency room – and help them manage a frightening
situation (such as their child not “acting right” for quite a while after sedation). In the rare
instance where a child is suffering prolonged nausea and vomiting or some other serious
complication of the sedation, contact could enable the provider to head off a really dangerous
situation. Perhaps most importantly, a consistent call would be good professional practice,
resulting in increased patient satisfaction and a clearer understanding of the implications of the
medications and procedures we provide.
    On the other hand it should be noted that in surgery circles, the post operative call is aimed as
much as following up the possible complications of the procedure as much as the
sedation/anesthesia. In the case where a child receives very brief sedation for a non-invasive test
(i.e. CT scan), the likelihood of finding major problems with a post-sedation phone call is
probably quite low.
     Staffing considerations aside, a post sedation call seems like an excellent idea (probably
more needed in some situations than others), but as far as we know it is not a standard of care at
this point.

We invite reader comment on this issue.

Literature Review:

1)Malviya S, Voepel-Lewis T, Ludomirsky A, Marshall J, Tait AR. Can We Improve the
Assessment of Discharge Readiness?: A Comparative Study of Observational and Objective
Measures of Depth of Sedation in Children. Anesthesiology. 2004,100, (2) 218-224

Abstract: The authors point out that current recommended discharge criteria might not be
rigorous enough to detect residual sedation. This study evaluated the use of the Bispectral Index
(BIS® monitor), the University of Michigan Sedation Scale (UMSS; i.e., 0-4 observational
scale), and a Modified Maintenance of Wakefulness Test (MMWT; visual observation of the
time the child is able to stay awake) in assessing return to baseline status. Twenty-nine children
sedated for echocardiographic examination were studied. Nurses administered sedatives and
monitored and discharged children according to institutional guidelines. Children were
monitored with the BIS® throughout the study. Trained observers assigned UMSS scores every
10-15 min until revised discharge criteria were met (i.e., UMSS score of 0 or 1, MMWT duration
= 20 min). The MMWT value was recorded at each observation following the procedure.
Subsequently, blinded observers recorded average BIS values for the 5 min before each UMSS
observation.

Results showed that there were moderate correlations between the BIS, MMWT, and UMSS
scores (r = 0.68-0.78; P < 0.01). Revised criteria correctly identified children who were awake
and alert (BIS value = 90) in 88% of the cases. Only 55% of the children had returned to baseline
BIS values when discharged by the nurse, compared with 92% when revised criteria were met (P
< 0.05). It took longer to meet revised criteria compared with standard criteria (75.3 ± 76.2 min
vs. 16.4 ± 13.1 min; P = 0.001). The authors concluded that the incorporation of specific,
objective discharge criteria (i.e., UMSS score of 0 or 1, MMWT duration = 20 min) may ensure
a status closer to baseline (BIS value = 90) compared with nursing judgment using standard
criteria. However, such assurance may delay the discharge of sedated children.

Commentary: Not sure what the implications are for our phone call question (above). We
compliment this effort to put a more scientific framework on discharge criteria - which have
previously often been described in “fuzzy” terminology concerning return to baseline status.
There is no doubt that institution of more standardized and objective criteria for discharge results
in patients more closely approximating their baseline status at the time of discharge. The
question still to be raised after a study such as this is whether or not outcomes are changed? On
face value alone, one would assume the answer to that question is “yes”, however that data is
still lacking. Would the institution of these criteria help us avoid any future incidents of children
being discharged after sedation with airway reflexes still significantly impaired - only to slump
over and suffocate in their car seats on the way home? (Coté et. al. Pediatrics 105 805-14, 2000)
Stated another way does keeping children for an extra hour after meeting a defined nursing
standard (in order to pass a more rigorous set of criteria) result in prevention of significant
problems? Such a follow-up study would be welcome.

This study is also interesting for its use of the BIS® monitor as a standard against which to
measure patients and their level of sedation. For those who are not familiar with it, the BIS®
stands for Bispectral Index Score and essentially is a processed EEG that can be derived from 3
electrodes placed on the forehead. The output of this monitor reads from 0 to 100 and gives a
rough evaluation of the depth of sedation or anesthesia for a given patient at that moment. The
producers of this instrument have been fairly aggressive in their marketing for its use in all areas
of anesthesia for many years now. I believe it would be fair to say that the response has been
mixed with some centers using the instrument a lot and others using it very little. Although we
have not used it extensively during pediatric sedation ourselves, we are seeing increasing use of
this instrument in sedation research. While it may not, as of yet, have a role in day to day
sedation work, there seems to be an evolving niche for this monitor in clinical investigation and
perhaps the ICU.

This article was accompanied by an editorial by Charles Coté in the same issue of
Anesthesiology entitled Discharge Criteria for Children Sedated by Nonanesthesiologists: Is
"Safe" Really Safe Enough? Anesthesiology 2004 100 (2) 207-9. This paper traces the evolution
of guidelines for sedation and their role in helping to improve safety in the sedation practice. Dr.
Coté points out the adverse events that have accompanied inappropriate discharge of patients
while still sedated. He points out that parents themselves may be helpful in the prolonged
observation process that may result when more strict discharge criteria are employed. He calls
for more research (like that of Malviya and colleagues) where objective scientific methods are
used to establish the safest possible discharge criteria.
Two studies along with an editorial appeared in Annals of Emergency Medicine this winter. I
apologize ahead of time for those who are tired of hearing about propofol…..

2) Bassett K E, Anderson J L, Pribble C G, Guenther E. Propofol for procedural sedation in
children in the emergency department. Annals of Emergency Medicine. 2003 42, (6) 773-82.

Abstract: The authors wished to determine the safety and efficacy of propofol sedation for
painful procedures in the emergency department (ED). To accomplish this, a consecutive case
series of propofol sedations for painful procedures in the ED of a tertiary care pediatric hospital
from July 2000 to July 2002 was performed. A sedation protocol was followed. Propofol was
administered in a bolus of 1 mg/kg, followed by additional doses of 0.5 mg/kg. Narcotics were
administered 1 minute before propofol administration. Adverse events were documented, as were
the sedation duration, recovery time from sedation, and total time in the ED. Three hundred
ninety-three discrete sedation events with propofol were analyzed. Procedures consisted of the
following: fracture reductions (94%), reduction of joint dislocations (4%), spica cast placement
(2%), and ocular examination after an ocular burn (0.3%). The median propofol dose was 2.7
mg/kg. Ninety-two percent of patients had a transient (≤2 minutes) decrease in systolic blood
pressure without clinical signs of poor perfusion. Nineteen (5%) patients had hypoxia, 11 (3%)
patients required airway repositioning or jaw-thrust maneuvers, and 3 (0.8%) patients required
bag-valve-mask ventilation. No patient required endotracheal intubation. Propofol sedation is
efficacious and can be used safely in the ED setting under the guidance of a protocol. Transient
cardiopulmonary depression occurs, which requires vigilant monitoring by highly skilled
practitioners. They conclude that propofol is well suited for short, painful procedures in the ED
setting.

3) Guenther E, Pribble CG, Junkins EP, Kadish HA, Bassett KE, Nelson DS. Propofol sedation
by emergency physicians for elective pediatric outpatient procedures. Annals of Emergency
Medicine. 2003 42(6) 783-91

Abstract: The authors describe the efficacy of propofol sedation administered by pediatric
emergency physicians to facilitate painful outpatient procedures. A protocol for patients
receiving propofol sedation in an emergency department-affiliated short-stay unit was instituted.
A prospective, consecutive case series was performed from January to September 2000. Patients
were prescheduled, underwent a medical evaluation, and met fasting requirements. A sedation
team was present throughout the procedure. All patients received supplemental oxygen. Sedation
depth and vital signs were monitored while propofol was manually titrated to the desired level of
sedation. Results showed that there were 291 separate sedation events in 87 patients. No patient
had more than 1 sedation event per day. Median patient age was 6 years; 57% were male patients
and 72% were oncology patients. Many children required more than 1 procedure per encounter.
Most commonly performed procedures included lumbar puncture (43%), intrathecal
chemotherapy administration (31%), bone marrow aspiration (19%), and bone biopsy (3%).
Median total propofol dose was 3.5 mg/kg. Median systolic and diastolic blood pressures were
lowered 22 mm Hg (range 0 to 65 mm Hg) and 21 mm Hg (range 0 to 62 mm Hg), respectively.
Partial airway obstruction requiring brief jaw-thrust maneuver was noted for 4% of patient
sedations, whereas transient apnea requiring bag-valve-mask ventilation occurred in 1% of
patient sedations. All procedures were successfully completed. Median procedure duration was
13 minutes, median sedation duration was 22 minutes, and median total time in the short stay
unit was 40 minutes. The authors conclude that propofol sedation administered by emergency
physicians safely facilitated short painful procedures in children under conditions studied, with
rapid recovery.

Comment: These studies are important to review for many reasons. First, in fairness, it should
be recognized that they come from the same institution with many of the same authors on both
papers. This is a critical point since (as the authors point out) their conclusions about safety are
directed at the context and conditions under which the studies were performed. In this case a
major children’s hospital and teaching institution. Clearly the rescue and back-up systems that
are present 24 hours a day are different in this situation than they might be in a community
hospital emergency department. As always, we need to note that even at several hundred
patients, the numbers are very small to make sweeping generalizations about the safety of this
practice.

The studies are very important in that there are very few studies that systematically review the
use of propofol in the emergency department involving children. As the use of propofol is
rapidly becoming very wide-spread in emergency departments across the country, reports such as
these are sorely needed in order to better understand the nature of propofol use and to categorize
the benefits and risks. It will be reassuring when we have reports of its use in tens of thousands
of patients having a wider variety of procedures and in varying venues.

In describing their experience with protocol driven propofol delivery, the authors should be
complimented for including their careful patient selection process. Even in the non-elective cases
(Bassett), patients were all ASA I or II and had been fasted for at least 3 hours. None had
significant airway abnormalities. When considering the outcomes from these studies, this
screening process should be taken into account.

While not readily apparent from the abstracts, both of these studies (not just Bassett) involved
the use of adjunctive opiates for any procedure that was deemed “painful”. This is a critical point
since movement during painful procedures such as lumbar punctures can be unacceptable if not
accompanied by adjunctive opiates - unless the dose of propofol is extremely large. The opiate
administered in the Guenther study was fentanyl (1-2mcg/kg) one minute prior to the
administration of propofol, while in the Bassett study it was morphine for pain in the emergency
department (dose determined by the emergency medicine physician) with 1-2mcg/kg of fentanyl
given prior to the administration of propofol. Interestingly, the investigators did not give opiates
to children who were on chronic opiate therapy when it might be argued that those patients
would need the adjunctive opiates more that any other population.

One real drawback of these two studies is the lack of any type of objective pain or sedation scale
used to describe the state of the patients during procedures. The authors state that “non-
purposeful movement that did not interfere with the procedure and verbalizations including
moaning or minimal crying were tolerated without additional medication administration”. This
type of methodology leaves the reader uncertain of the exact effectiveness of the sedation that
was provided. With a strong enough helper exactly what type of movement interferes with the
procedure?
It is always hard to know how to consider the complications mentioned in studies such as these.
Mild hypoxemia that is readily reversed by manipulation of the jaw or chin may not represent a
major problem at all. On the other hand, the 1% incidence of apnea requiring bag-mask
ventilation remains a strong reminder that only those absolutely comfortable with the
management of pediatric airways should undertake this practice. The requirement for advanced
airway interventions such as endotracheal intubation has been reported with propofol use in
similar situations but is rare enough that it would not reliably show up in studies of this size and
this patient population. Finally, we are always interested in the inclusion of hypotensive data in
studies of propofol sedation. In the setting of brief sedation with a bolus of propofol in an
otherwise well child, what decrease in blood pressure is unexpected and in need of intervention
(or mention)? We would argue that a mild decrease in blood pressure is indeed normal after a
bolus of propofol and while it should be tracked, only very significant decreases should be
reported as findings that are worthy of note.

These papers were accompanied by an article entitled Propofol in the Emergency Medicine:
Pushing the Sedation Frontier. Annals of Emergency Medicine 2003 Vol 42 (6) 792-7. .
Authors, Steven Green MD and Baruch Krauss MD, have published extensively on sedation in
the emergency department and their work has regularly been a part of this newsletter. This paper
reviews the previous reported literature on propofol use in the emergency department, the key
points of the Bassett and Guenther studies, and the various questions that have been raised about
propofol use. We will not attempt to summarize the entire content of this article - it should be
read in its entirety. We would like to point out that the authors conclude that based on the
information provided by the two articles mentioned above (together with sparse reported
literature before this), propofol is an accepted standard of care in the emergency department.
They state “some anesthesiologists will maintain that studies the size of those existing for
general anesthesia, literally hundreds of thousands of cases, are necessary to validate the profile
of newer procedural sedation and analgesia agents. Most established therapies are based on
hundreds rather than thousands or patients, and ED practice patterns and standard of care must
of necessity be based on smaller samples.”

Commentary: It is interesting that the authors single out anesthesiologists in this way. We
would like to note that it is not just anesthesiologists who require large numbers of patients to
establish the safe use of new protocols or therapeutic regimens. However, perhaps it is their
insistence on excellent evidence to guide their practice that has given anesthesiologists the best
record for safety and quality improvement in the field of medicine – as noted in the last two
Institute of Medicine reports on the subject. When discussing future improvements in safety
related to health care, Lucian Leape comments “Anesthesia is the only system in healthcare that
begins to approach the vaunted “six sigma” level of perfection that other industries strive for.”
[1] It would be foolish to apologize for, or retreat from advocating for these standards.

It should be noted that (concerning the content of this newsletter) our comments never address
“standard of care” but rather the conclusions at the end of sedation studies that state “regimen X
is safe and effective”. The issue of safety has to be considered in context. In this particular case
we stand by the statement that roughly seven hundred encounters in less than 400 children at one
institution can not begin to prove “safety” in a field where critical incidents should only occur on
the order of one in tens of thousands of encounters. On the other hand, standard of care is much
more difficult to define and we would not attempt to take on that task.

We would also like to point out that Dr. Green and Dr. Krauss may be correct that some
standards are based on “hundreds” of case experiences; and that makes sense concerning care of
relatively rare entities or infrequent therapeutic strategies. In the case of propofol however,
contact with emergency medicine physicians and data from the Pediatric Sedation Research
Consortium would indicate that, hundreds or even thousands of children are receiving propofol
in emergency departments every day. We would encourage many more reports on its usage. We
believe the gold standard level of evidence for safety (as they cite for anesthesiology) really
would not be that hard to come by.

1) Leape, L.L., D.M. Berwick, and D.W. Bates, What practices will most improve safety? Evidence-based medicine
meets patient safety. Jama, 2002. 288(4): p. 501-7.

As always we appreciate your comments and thoughts.

								
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