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Propofol for procedural sedation in the pediatric emergency department
The Journal of Emergency Medicine, Vol. 27, No. 1, pp. 11–14, 2004 Copyright © 2004 Elsevier Inc. Printed in the USA. All rights reserved 0736-4679/04 $–see front matter
doi:10.1016/j.jemermed.2004.02.004
Original Contributions
PROPOFOL FOR PROCEDURAL SEDATION IN THE PEDIATRIC EMERGENCY DEPARTMENT Jay Pershad,
MD
and Sandip A. Godambe,
MD, PhD
Division of Critical Care & Emergency Services, Department of Pediatrics, LeBonheur Children’s Medical Center, Memphis, Tennessee Reprint Address: Jay Pershad, MD, Emergency Department, Le Bonheur Children’s Medical Center, 50 N Dunlap St., Memphis, TN 38103
e Abstract—This retrospective case series reports our experience using propofol for procedural sedation in the Emergency Department over an 18-month period with 52 pediatric patients. Propofol sedation was performed successfully in all children (mean age, 10.2 years; range 0.7– 17.4 years). Indications for sedation included orthopedic manipulation, incision and drainage of abscess, sexual assault examination, laceration repair, and non-invasive imaging studies. The mean dose administered with the intermittent bolus and continuous infusion methods of delivery was 4.25 mg/kg (ⴞ 1.86) and 8.3 mg/kg/h, respectively. The mean recovery time was 27.1 min (ⴞ 15.84). No patient required assisted ventilation or developed clinically significant hypotension. Respiratory depression requiring airway repositioning or supplemental oxygen was noted in 5.8% (3/52) patients. Propofol is a reasonable alternative to facilitate sedation for a range of procedures performed in a busy Pediatric Emergency Department. © 2004 Elsevier Inc.
increasingly being used by non-anesthesiologists to facilitate procedures outside of the traditional operating room setting (2– 6). Propofol represents an alternative agent for provision of sedation during pediatric emergency procedures. It has a rapid onset and offset with a smooth recovery profile. It is an anti-emetic with no anesthetic hangover (7). It is a potent agent, with respiratory depression and hypotension as important side effects (1,3,5). Propofol was recently approved for clinical use in our Emergency Department (ED). We report our experience with its use to illustrate an approach to propofol sedation over a wide range of clinical indications that include painful and non-painful procedures performed in the Pediatric ED.
MATERIALS AND METHODS e Keywords—propofol; procedural sedation; emergency department
Patients who had received propofol for sedation in the ED of LeBonheur Children’s Medical Center during an 18-month period (from January 2001 to June 2002) were identified utilizing sedation records maintained in our pharmacy. Our ED is located in an urban tertiary care Children’s Hospital with an annual census of 65,000 patient visits. Hospital records were retrospectively reviewed after receiving Institutional Review Board approval. Data obtained included patient age, weight and
INTRODUCTION Propofol (2.6 diisopropylphenol) is an ultra-short acting non-opioid non-barbiturate sedative hypnotic agent that is used extensively as an induction agent by pediatric anesthesiologists (1). Due to its favorable properties, it is
RECEIVED: 14 March 2003; FINAL ACCEPTED: 5 February 2004
SUBMISSION RECEIVED:
4 December 2003; 11
12
J. Pershad and S. A. Godambe
Table 1. Protocol for Use of Propofol for Procedural Sedation in the Pediatric Emergency Department Contraindications: ASA Category ⬎ II, Potential for difficult airway, Egg or soy allergy Propofol was injected slowly over at least 1–2 min with an initial induction dose of 1 mg/kg or until eye closure. Repeated aliquots of 0.5 mg/kg over 30–60 titrated to achieve a relatively motionless state during the procedure. A continuous infusion via a syringe pump was titrated when a procedure of longer duration was anticipated. Lidocaine 10 mg may be added to 100 mg of propofol to reduce the pain of injection. Pre-oxygenation is recommended at the discretion of the emergency provider. Adjunctive opiate analgesia for painful procedures because propofol has no intrinsic analgesic properties
diagnosis; procedures performed; presence of co-morbidity; time since last oral intake; induction and recovery time; occurrence of side effects; the use of adjuvant analgesics, and success of the procedure. The sedation was deemed successful if the procedure was completed during the initial sedation attempt. We excluded two patients with severe head trauma on mechanical ventilation who had received propofol infusion for ongoing sedation. Administration time was defined as the time interval between the first and last dose of propofol. Recovery time was the time from last dose of propofol until return to “baseline” as determined by the independent sedation nurse assigned to the patient. This was in accordance with our institution’s discharge policy after sedation. To be eligible for discharge the patient must be awake and able to tolerate an oral feeding. Total sedation time was defined as the time interval between the first dose of propofol until return to baseline. Hypotension was defined as systolic blood pressure less than 5th percentile for age that was not transient or accompanied by a change in perfusion. Respiratory depression was defined as the need for assisted ventilation (bag-mask-valve or endotracheal intubation), airway repositioning maneuvers, or hypoxemia (oxygen saturation ⬍ 90%). Although respiratory rate was not factored into this definition, chest excursion was continuously monitored during the sedation. The protocol for delivery of propofol was in accordance with our departmental policy that was approved by the sedation committee of the hospital. All patients had continuous cardio-respiratory monitoring, pulse oximetry, and intermittent non-invasive (every 3–5 min) monitoring of their blood pressures. A sedation nurse (Registered Nurse), who is solely responsible for patient monitoring and documentation, was present in the room at all times. All patients received an initial bolus of propofol (1 mg/kg) that was followed by titration of smaller aliquots of 0.5 mg/kg until the desired level of sedation was achieved, as determined by the Emergency Physician (EP) administering the medication (Table 1). Patients were commonly pre-oxygenated and some received 1% intravenous lidocaine (10 mg) to reduce the pain of propofol injection. The dose of propofol and use
of adjuvant agents was at the discretion of the Pediatric EP. Results are expressed as mean values ⫾ standard deviation (SD). All statistical tests were performed using Prism (GraphPad, San Diego, CA). RESULTS There were 52 patients who had received propofol for procedural sedation during the study period. This includes one patient who was sedated twice during separate ED encounters. Thirty-one were boys. The mean age of the study population was 10.2 years (range: 0.7–17.4 years). The frequency of procedures performed under propofol sedation were as follows: Extremity fracture manipulation (n ⫽ 35); shoulder dislocation (n ⫽ 3); noninvasive imaging studies (n ⫽ 2); incision and drainage of abscesses (n ⫽ 6); nail bed laceration repair (n ⫽ 2); complex facial laceration (n ⫽ 2); burn debridement (n ⫽ 2); sexual assault examination (n ⫽ 1); and removal of foreign body within the auditory canal (n ⫽ 1). The total number of procedures was greater than 52 because in two subjects multiple procedures were done simultaneously. One was a victim of a motor vehicle crash who underwent right humeral fracture manipulation and left shoulder relocation during the sedation. The second patient had bilateral extremity fracture manipulation. The majority (49/52) of the patients did not have any co-morbidity. There was 1 patient each with asthma, seizure disorder, and ventriculoperitoneal shunt who underwent sedation with propofol. Eighty-one percent (42/52) of all subjects received opiate analgesia at some time before propofol administration. Of this group, 36 patients had received intravenous (i.v.) morphine, 2 received i.v. fentanyl, 2 were administered intramuscular meperidine and 1 received oral acetaminophen with codeine. Two patients had received intravenous lidocaine local anesthesia to counteract the pain of injection. Seventy-one percent (37/52) were pre-oxygenated during the procedure. The mean recovery time was 27.1 min (⫾ 15.84). The average total sedation time was 39.1 min (⫾ 19.43). We excluded the 6 patients who received propofol by continuous infusion
Propofol Procedural Sedation
13
Table 2. Characteristics of Subjects Receiving Propofol via Continuous Infusion to Facilitate Procedures in the Emergency Department Age (yrs)
Diagnosis
TST (minutes)
Loading (mg/kg)
Infusion (mg/kg/h)
1.2 15.2 0.7 11.2 17.4 14.3
Digit amputation with nailbed repair in a patient with asthma Labial abscess incision and drainage Sedation for abdominal imaging (Computed Tomography scan) Incision and drainage of multiple abscesses Perineal abscess incision and drainage Sexual assault examination in a patient with mental retardation and seizure disorder
90 57 46 56 35 56
2.2 1 3.5 1 2.7 1.6
9 5 12 10 6 7.6
(Table 2) and determined the mean total dose of propofol administered by the intermittent bolus method to be 4.25 (⫾ 1.86) mg/kg. The average infusion rate of propofol among the 6 patients who received the medication via continuous infusion was 8.3 mg/kg/h. There were 5.8% (3/52) of patients receiving propofol who developed transient hypoxemia (oxygen saturation ⬍ 90%) due to partial airway obstruction, which resolved with airway repositioning and supplemental oxygen. None of the patients required assisted ventilation or experienced hypotension. Similarly, no patient experienced side effects like emesis, laryngospasm or dysphoria. All procedures facilitated with propofol were deemed successful except for one subject who was sedated for removal of a foreign body in the auditory canal. Although the sedation was satisfactory, the removal was unsuccessful.
DISCUSSION Many sedative agents are available to reduce procedurerelated distress in the ED. The ideal agent, in a busy ED setting, would be one that will achieve behavioral control rapidly and effectively, have a rapid offset, and be devoid of side effects. Commonly used medication regimens for procedural sedation and analgesia include ketamine, benzodiazepines, and opiates (8 –10). Ketamine has the potential for undesirable side effects that include emesis and dysphoria in the recovery period (9,10). It also has a relatively prolonged recovery time, with residual drowsiness and confusion. The mean recovery time in a controlled trial with ketamine-only sedation was 64 min (9). With fentanyl and benzodiazepines, the dose required to perform the procedure, without the use of physical restraints or patient discomfort, frequently results in significant respiratory depression. In a controlled trial involving administration of midazolam and fentanyl for orthopedic manipulation in the ED, 25% of patients developed hypoxemia. The mean recovery time (from first dose until return to baseline status) was 113.7 min (8). Moreover, 8% of patients developed emesis at
some time during the first 24 h of the procedure. Patients who received fentanyl/midazolam had higher scores (greater distress) on the revised Observational Scale of Behavioral Distress scale as compared with a group that was administered ketamine/midazolam (8). Etomidate recently has been reported as an effective alternative for ED procedural sedation. It is less well studied in the pediatric population. Like propofol, it is also an ultra-short acting sedative hypnotic with a similar pharmacokinetic profile. It is also a potent respiratory depressant with additional side effects that include transient myoclonus, pain on injection, and hypotension (11). Unlike propofol, it has a propensity to cause emesis in the recovery period. There are limited data on the use of propofol in the Pediatric ED. Havel et al. first reported a controlled trial comparing propofol and midazolam for emergent closed orthopedic reductions in a pediatric ED. Mild transient hypoxia (11.6% with propofol and 10.9% with midazolam) was the most significant complication in both groups. The mean recovery time in this trial using morphine and propofol for fracture manipulation was 14.9 ⫾ 11.1 min (5). We believe that the comparatively shorter recovery period may be related to the difference in dose of propofol administered. The mean dose of propofol in this study was a loading dose of 1 mg/kg with an infusion rate of 67–117 mcg/kg/min (4 –7 mg/kg/h). These doses are lower than those reported in our subjects. The mean induction and recovery times from propofol anesthesia were 3.9 and 28.8 min, respectively, in a retrospective cohort of patients who received propofol to facilitate procedural sedation in the pediatric intensive care unit (4). We are aware of one prior study that describes the use of propofol for procedural sedation in the Pediatric ED, over a broad range of indications (3). A 30% incidence of desaturation was noted in this prospective cohort of patients. The majority of their patients underwent sedation for fracture manipulation. The mean dose and recovery time in this study by Skokan et al. were 3.3 mg/kg and 18 min, respectively. We speculate that because the majority of subjects (70%) had received fentanyl imme-
14
J. Pershad and S. A. Godambe
Table 3. Limitations of the Study Retrospective design Charting bias Diverse group of procedures performed Non-standardized use of adjunctive agents No systematic measure of pain, recall or patient satisfaction Did not measure depth of sedation Small sample size
diately before the painful procedure, the mean dose of propofol administered was lower than the mean dose in our study. The 3 patients in our study who developed respiratory depression were also undergoing fracture manipulation. All 3 had received opiate analgesia before the administration of propofol. We speculate that opiate use immediately before the administration of propofol may have increased the risk for respiratory depression. We were unable to comment on the impact of opiate use on the overall dose of propofol required during painful procedures due to the variability in the type, as well as the dose and timing, of opiates administered. Propofol has the advantage of a rapid onset and a short half-life leading to a timely recovery from sedation. It is also uniquely able to be titrated to the desired level of patient comfort. For relatively longer duration procedures, once the level of sedation is determined to be adequate, a maintenance drip may be initiated. This avoids the repetitive administration of bolus doses and medication stacking, which can occur with longer-acting sedative-hypnotics. The infusion may be turned off with a quick recovery, to enable evaluation of the patient’s neurologic status. This paralytic sparing role may be important in head-injured patients who are mechanically ventilated. Moreover, patients sedated with propofol emerge with a “clear head” without nausea or dysphoria. In one study evaluating patient preferences for postoperative anesthesia outcomes, avoiding nausea and vomiting was rated a high priority. It ranked higher than incisional pain and recall without pain (12).
LIMITATIONS The study is subject to the usual limitations of retrospective design (Table 3). The wide range of age groups, underlying medical conditions, and indications represented in our population may introduce bias and limit applicability of study conclusions. Similarly, the recording of induction time and recovery time by our “sedation” nurses may be subject to charting bias. However, our recovery time is comparable with prior data using propofol. Besides, the documentation by our “sedation”
nurses is usually meticulous. It is also for this reason that we believe it is unlikely that we missed any significant side effects like apnea or desaturation or hypotension. Despite this, we may have underestimated minor side effects such as pain on injection, brief myoclonus during induction, and use of light restraint during the most noxious period of the procedure. It must be noted that we did not make any systematic observations about the quality of sedation or recovery. CONCLUSIONS In summary, we present our experience with propofol for procedural sedation in the Pediatric ED. Transient respiratory depression may be encountered with its use. Careful monitoring and strict adherence to a protocol is suggested when using propofol for deep sedation. It offers a useful alternative to other sedative hypnotics, with some unique advantages. REFERENCES 1. Bryson HM, Fulton BR, Faulds D. Propofol. An update of its use in anaesthesia and conscious sedation. Drugs 1995;50:513–59. 2. Vardi A, Salem Y, Padeh S, Paret G, Barzilay Z. Is propofol safe for procedural sedation in children? A prospective evaluation of propofol versus ketamine in pediatric critical care. Crit Care Med 2002;30:1231– 6. 3. Skokan EG, Pribble C, Bassett KE, Nelson DS. Use of propofol sedation in a pediatric emergency department: a prospective study. Clin Pediatr (Phila) 2001;40:663–71. 4. Hertzog JH, Dalton HJ, Anderson BD, Shad AT, Gootenberg JE, Hauser GJ. Prospective evaluation of propofol anesthesia in the pediatric intensive care unit for elective oncology procedures in ambulatory and hospitalized children. Pediatrics 2000;106:742–7. 5. Havel CJ Jr, Strait RT, Hennes H. A clinical trial of propofol vs midazolam for procedural sedation in a pediatric emergency department. Acad Emerg Med 1999;6:989 –97. 6. Hostetler MA, Auinger P, Szilagyi PG. Parenteral analgesic and sedative use among ED patients in the United States: combined results from the National Hospital Ambulatory Medical Care Survey (NHAMCS) 1992–1997. Am J Emerg Med 2002;20:83–7. 7. Martin TM, Nicolson SC, Bargas MS. Propofol anesthesia reduces emesis and airway obstruction in pediatric outpatients. Anesth Analg 1993;76:144 – 8. 8. Kennedy RM, Porter FL, Miller JP, Jaffe DM. Comparison of fentanyl/midazolam with ketamine/midazolam for pediatric orthopedic emergencies. Pediatrics 1998;102:956 – 63. 9. Sherwin TS, Green SM, Khan A, Chapman DS, Dannenberg B. Does adjunctive midazolam reduce recovery agitation after ketamine sedation for pediatric procedures? A randomized, doubleblind, placebo-controlled trial. Ann Emerg Med 2000;35:229 –38. 10. Wathen JE, Roback MG, Mackenzie T, Bothner JP. Does midazolam alter the clinical effects of intravenous ketamine sedation in children? A double-blind, randomized, controlled, emergency department trial. Ann Emerg Med 2000;36:579 – 88. 11. Rothermel LK. Newer pharmacologic agents for procedural sedation of children in the emergency department-etomidate and propofol. Curr Opin Pediatr 2003;15:200 –3. 12. Macario A, Weinger M, Carney S, Kim A. Which clinical anesthesia outcomes are important to avoid? The perspective of patients. Anesth Analg 1999;89:652– 8.
doi:10.1016/j.jemermed.2004.02.004
Original Contributions
PROPOFOL FOR PROCEDURAL SEDATION IN THE PEDIATRIC EMERGENCY DEPARTMENT Jay Pershad,
MD
and Sandip A. Godambe,
MD, PhD
Division of Critical Care & Emergency Services, Department of Pediatrics, LeBonheur Children’s Medical Center, Memphis, Tennessee Reprint Address: Jay Pershad, MD, Emergency Department, Le Bonheur Children’s Medical Center, 50 N Dunlap St., Memphis, TN 38103
e Abstract—This retrospective case series reports our experience using propofol for procedural sedation in the Emergency Department over an 18-month period with 52 pediatric patients. Propofol sedation was performed successfully in all children (mean age, 10.2 years; range 0.7– 17.4 years). Indications for sedation included orthopedic manipulation, incision and drainage of abscess, sexual assault examination, laceration repair, and non-invasive imaging studies. The mean dose administered with the intermittent bolus and continuous infusion methods of delivery was 4.25 mg/kg (ⴞ 1.86) and 8.3 mg/kg/h, respectively. The mean recovery time was 27.1 min (ⴞ 15.84). No patient required assisted ventilation or developed clinically significant hypotension. Respiratory depression requiring airway repositioning or supplemental oxygen was noted in 5.8% (3/52) patients. Propofol is a reasonable alternative to facilitate sedation for a range of procedures performed in a busy Pediatric Emergency Department. © 2004 Elsevier Inc.
increasingly being used by non-anesthesiologists to facilitate procedures outside of the traditional operating room setting (2– 6). Propofol represents an alternative agent for provision of sedation during pediatric emergency procedures. It has a rapid onset and offset with a smooth recovery profile. It is an anti-emetic with no anesthetic hangover (7). It is a potent agent, with respiratory depression and hypotension as important side effects (1,3,5). Propofol was recently approved for clinical use in our Emergency Department (ED). We report our experience with its use to illustrate an approach to propofol sedation over a wide range of clinical indications that include painful and non-painful procedures performed in the Pediatric ED.
MATERIALS AND METHODS e Keywords—propofol; procedural sedation; emergency department
Patients who had received propofol for sedation in the ED of LeBonheur Children’s Medical Center during an 18-month period (from January 2001 to June 2002) were identified utilizing sedation records maintained in our pharmacy. Our ED is located in an urban tertiary care Children’s Hospital with an annual census of 65,000 patient visits. Hospital records were retrospectively reviewed after receiving Institutional Review Board approval. Data obtained included patient age, weight and
INTRODUCTION Propofol (2.6 diisopropylphenol) is an ultra-short acting non-opioid non-barbiturate sedative hypnotic agent that is used extensively as an induction agent by pediatric anesthesiologists (1). Due to its favorable properties, it is
RECEIVED: 14 March 2003; FINAL ACCEPTED: 5 February 2004
SUBMISSION RECEIVED:
4 December 2003; 11
12
J. Pershad and S. A. Godambe
Table 1. Protocol for Use of Propofol for Procedural Sedation in the Pediatric Emergency Department Contraindications: ASA Category ⬎ II, Potential for difficult airway, Egg or soy allergy Propofol was injected slowly over at least 1–2 min with an initial induction dose of 1 mg/kg or until eye closure. Repeated aliquots of 0.5 mg/kg over 30–60 titrated to achieve a relatively motionless state during the procedure. A continuous infusion via a syringe pump was titrated when a procedure of longer duration was anticipated. Lidocaine 10 mg may be added to 100 mg of propofol to reduce the pain of injection. Pre-oxygenation is recommended at the discretion of the emergency provider. Adjunctive opiate analgesia for painful procedures because propofol has no intrinsic analgesic properties
diagnosis; procedures performed; presence of co-morbidity; time since last oral intake; induction and recovery time; occurrence of side effects; the use of adjuvant analgesics, and success of the procedure. The sedation was deemed successful if the procedure was completed during the initial sedation attempt. We excluded two patients with severe head trauma on mechanical ventilation who had received propofol infusion for ongoing sedation. Administration time was defined as the time interval between the first and last dose of propofol. Recovery time was the time from last dose of propofol until return to “baseline” as determined by the independent sedation nurse assigned to the patient. This was in accordance with our institution’s discharge policy after sedation. To be eligible for discharge the patient must be awake and able to tolerate an oral feeding. Total sedation time was defined as the time interval between the first dose of propofol until return to baseline. Hypotension was defined as systolic blood pressure less than 5th percentile for age that was not transient or accompanied by a change in perfusion. Respiratory depression was defined as the need for assisted ventilation (bag-mask-valve or endotracheal intubation), airway repositioning maneuvers, or hypoxemia (oxygen saturation ⬍ 90%). Although respiratory rate was not factored into this definition, chest excursion was continuously monitored during the sedation. The protocol for delivery of propofol was in accordance with our departmental policy that was approved by the sedation committee of the hospital. All patients had continuous cardio-respiratory monitoring, pulse oximetry, and intermittent non-invasive (every 3–5 min) monitoring of their blood pressures. A sedation nurse (Registered Nurse), who is solely responsible for patient monitoring and documentation, was present in the room at all times. All patients received an initial bolus of propofol (1 mg/kg) that was followed by titration of smaller aliquots of 0.5 mg/kg until the desired level of sedation was achieved, as determined by the Emergency Physician (EP) administering the medication (Table 1). Patients were commonly pre-oxygenated and some received 1% intravenous lidocaine (10 mg) to reduce the pain of propofol injection. The dose of propofol and use
of adjuvant agents was at the discretion of the Pediatric EP. Results are expressed as mean values ⫾ standard deviation (SD). All statistical tests were performed using Prism (GraphPad, San Diego, CA). RESULTS There were 52 patients who had received propofol for procedural sedation during the study period. This includes one patient who was sedated twice during separate ED encounters. Thirty-one were boys. The mean age of the study population was 10.2 years (range: 0.7–17.4 years). The frequency of procedures performed under propofol sedation were as follows: Extremity fracture manipulation (n ⫽ 35); shoulder dislocation (n ⫽ 3); noninvasive imaging studies (n ⫽ 2); incision and drainage of abscesses (n ⫽ 6); nail bed laceration repair (n ⫽ 2); complex facial laceration (n ⫽ 2); burn debridement (n ⫽ 2); sexual assault examination (n ⫽ 1); and removal of foreign body within the auditory canal (n ⫽ 1). The total number of procedures was greater than 52 because in two subjects multiple procedures were done simultaneously. One was a victim of a motor vehicle crash who underwent right humeral fracture manipulation and left shoulder relocation during the sedation. The second patient had bilateral extremity fracture manipulation. The majority (49/52) of the patients did not have any co-morbidity. There was 1 patient each with asthma, seizure disorder, and ventriculoperitoneal shunt who underwent sedation with propofol. Eighty-one percent (42/52) of all subjects received opiate analgesia at some time before propofol administration. Of this group, 36 patients had received intravenous (i.v.) morphine, 2 received i.v. fentanyl, 2 were administered intramuscular meperidine and 1 received oral acetaminophen with codeine. Two patients had received intravenous lidocaine local anesthesia to counteract the pain of injection. Seventy-one percent (37/52) were pre-oxygenated during the procedure. The mean recovery time was 27.1 min (⫾ 15.84). The average total sedation time was 39.1 min (⫾ 19.43). We excluded the 6 patients who received propofol by continuous infusion
Propofol Procedural Sedation
13
Table 2. Characteristics of Subjects Receiving Propofol via Continuous Infusion to Facilitate Procedures in the Emergency Department Age (yrs)
Diagnosis
TST (minutes)
Loading (mg/kg)
Infusion (mg/kg/h)
1.2 15.2 0.7 11.2 17.4 14.3
Digit amputation with nailbed repair in a patient with asthma Labial abscess incision and drainage Sedation for abdominal imaging (Computed Tomography scan) Incision and drainage of multiple abscesses Perineal abscess incision and drainage Sexual assault examination in a patient with mental retardation and seizure disorder
90 57 46 56 35 56
2.2 1 3.5 1 2.7 1.6
9 5 12 10 6 7.6
(Table 2) and determined the mean total dose of propofol administered by the intermittent bolus method to be 4.25 (⫾ 1.86) mg/kg. The average infusion rate of propofol among the 6 patients who received the medication via continuous infusion was 8.3 mg/kg/h. There were 5.8% (3/52) of patients receiving propofol who developed transient hypoxemia (oxygen saturation ⬍ 90%) due to partial airway obstruction, which resolved with airway repositioning and supplemental oxygen. None of the patients required assisted ventilation or experienced hypotension. Similarly, no patient experienced side effects like emesis, laryngospasm or dysphoria. All procedures facilitated with propofol were deemed successful except for one subject who was sedated for removal of a foreign body in the auditory canal. Although the sedation was satisfactory, the removal was unsuccessful.
DISCUSSION Many sedative agents are available to reduce procedurerelated distress in the ED. The ideal agent, in a busy ED setting, would be one that will achieve behavioral control rapidly and effectively, have a rapid offset, and be devoid of side effects. Commonly used medication regimens for procedural sedation and analgesia include ketamine, benzodiazepines, and opiates (8 –10). Ketamine has the potential for undesirable side effects that include emesis and dysphoria in the recovery period (9,10). It also has a relatively prolonged recovery time, with residual drowsiness and confusion. The mean recovery time in a controlled trial with ketamine-only sedation was 64 min (9). With fentanyl and benzodiazepines, the dose required to perform the procedure, without the use of physical restraints or patient discomfort, frequently results in significant respiratory depression. In a controlled trial involving administration of midazolam and fentanyl for orthopedic manipulation in the ED, 25% of patients developed hypoxemia. The mean recovery time (from first dose until return to baseline status) was 113.7 min (8). Moreover, 8% of patients developed emesis at
some time during the first 24 h of the procedure. Patients who received fentanyl/midazolam had higher scores (greater distress) on the revised Observational Scale of Behavioral Distress scale as compared with a group that was administered ketamine/midazolam (8). Etomidate recently has been reported as an effective alternative for ED procedural sedation. It is less well studied in the pediatric population. Like propofol, it is also an ultra-short acting sedative hypnotic with a similar pharmacokinetic profile. It is also a potent respiratory depressant with additional side effects that include transient myoclonus, pain on injection, and hypotension (11). Unlike propofol, it has a propensity to cause emesis in the recovery period. There are limited data on the use of propofol in the Pediatric ED. Havel et al. first reported a controlled trial comparing propofol and midazolam for emergent closed orthopedic reductions in a pediatric ED. Mild transient hypoxia (11.6% with propofol and 10.9% with midazolam) was the most significant complication in both groups. The mean recovery time in this trial using morphine and propofol for fracture manipulation was 14.9 ⫾ 11.1 min (5). We believe that the comparatively shorter recovery period may be related to the difference in dose of propofol administered. The mean dose of propofol in this study was a loading dose of 1 mg/kg with an infusion rate of 67–117 mcg/kg/min (4 –7 mg/kg/h). These doses are lower than those reported in our subjects. The mean induction and recovery times from propofol anesthesia were 3.9 and 28.8 min, respectively, in a retrospective cohort of patients who received propofol to facilitate procedural sedation in the pediatric intensive care unit (4). We are aware of one prior study that describes the use of propofol for procedural sedation in the Pediatric ED, over a broad range of indications (3). A 30% incidence of desaturation was noted in this prospective cohort of patients. The majority of their patients underwent sedation for fracture manipulation. The mean dose and recovery time in this study by Skokan et al. were 3.3 mg/kg and 18 min, respectively. We speculate that because the majority of subjects (70%) had received fentanyl imme-
14
J. Pershad and S. A. Godambe
Table 3. Limitations of the Study Retrospective design Charting bias Diverse group of procedures performed Non-standardized use of adjunctive agents No systematic measure of pain, recall or patient satisfaction Did not measure depth of sedation Small sample size
diately before the painful procedure, the mean dose of propofol administered was lower than the mean dose in our study. The 3 patients in our study who developed respiratory depression were also undergoing fracture manipulation. All 3 had received opiate analgesia before the administration of propofol. We speculate that opiate use immediately before the administration of propofol may have increased the risk for respiratory depression. We were unable to comment on the impact of opiate use on the overall dose of propofol required during painful procedures due to the variability in the type, as well as the dose and timing, of opiates administered. Propofol has the advantage of a rapid onset and a short half-life leading to a timely recovery from sedation. It is also uniquely able to be titrated to the desired level of patient comfort. For relatively longer duration procedures, once the level of sedation is determined to be adequate, a maintenance drip may be initiated. This avoids the repetitive administration of bolus doses and medication stacking, which can occur with longer-acting sedative-hypnotics. The infusion may be turned off with a quick recovery, to enable evaluation of the patient’s neurologic status. This paralytic sparing role may be important in head-injured patients who are mechanically ventilated. Moreover, patients sedated with propofol emerge with a “clear head” without nausea or dysphoria. In one study evaluating patient preferences for postoperative anesthesia outcomes, avoiding nausea and vomiting was rated a high priority. It ranked higher than incisional pain and recall without pain (12).
LIMITATIONS The study is subject to the usual limitations of retrospective design (Table 3). The wide range of age groups, underlying medical conditions, and indications represented in our population may introduce bias and limit applicability of study conclusions. Similarly, the recording of induction time and recovery time by our “sedation” nurses may be subject to charting bias. However, our recovery time is comparable with prior data using propofol. Besides, the documentation by our “sedation”
nurses is usually meticulous. It is also for this reason that we believe it is unlikely that we missed any significant side effects like apnea or desaturation or hypotension. Despite this, we may have underestimated minor side effects such as pain on injection, brief myoclonus during induction, and use of light restraint during the most noxious period of the procedure. It must be noted that we did not make any systematic observations about the quality of sedation or recovery. CONCLUSIONS In summary, we present our experience with propofol for procedural sedation in the Pediatric ED. Transient respiratory depression may be encountered with its use. Careful monitoring and strict adherence to a protocol is suggested when using propofol for deep sedation. It offers a useful alternative to other sedative hypnotics, with some unique advantages. REFERENCES 1. Bryson HM, Fulton BR, Faulds D. Propofol. An update of its use in anaesthesia and conscious sedation. Drugs 1995;50:513–59. 2. Vardi A, Salem Y, Padeh S, Paret G, Barzilay Z. Is propofol safe for procedural sedation in children? A prospective evaluation of propofol versus ketamine in pediatric critical care. Crit Care Med 2002;30:1231– 6. 3. Skokan EG, Pribble C, Bassett KE, Nelson DS. Use of propofol sedation in a pediatric emergency department: a prospective study. Clin Pediatr (Phila) 2001;40:663–71. 4. Hertzog JH, Dalton HJ, Anderson BD, Shad AT, Gootenberg JE, Hauser GJ. Prospective evaluation of propofol anesthesia in the pediatric intensive care unit for elective oncology procedures in ambulatory and hospitalized children. Pediatrics 2000;106:742–7. 5. Havel CJ Jr, Strait RT, Hennes H. A clinical trial of propofol vs midazolam for procedural sedation in a pediatric emergency department. Acad Emerg Med 1999;6:989 –97. 6. Hostetler MA, Auinger P, Szilagyi PG. Parenteral analgesic and sedative use among ED patients in the United States: combined results from the National Hospital Ambulatory Medical Care Survey (NHAMCS) 1992–1997. Am J Emerg Med 2002;20:83–7. 7. Martin TM, Nicolson SC, Bargas MS. Propofol anesthesia reduces emesis and airway obstruction in pediatric outpatients. Anesth Analg 1993;76:144 – 8. 8. Kennedy RM, Porter FL, Miller JP, Jaffe DM. Comparison of fentanyl/midazolam with ketamine/midazolam for pediatric orthopedic emergencies. Pediatrics 1998;102:956 – 63. 9. Sherwin TS, Green SM, Khan A, Chapman DS, Dannenberg B. Does adjunctive midazolam reduce recovery agitation after ketamine sedation for pediatric procedures? A randomized, doubleblind, placebo-controlled trial. Ann Emerg Med 2000;35:229 –38. 10. Wathen JE, Roback MG, Mackenzie T, Bothner JP. Does midazolam alter the clinical effects of intravenous ketamine sedation in children? A double-blind, randomized, controlled, emergency department trial. Ann Emerg Med 2000;36:579 – 88. 11. Rothermel LK. Newer pharmacologic agents for procedural sedation of children in the emergency department-etomidate and propofol. Curr Opin Pediatr 2003;15:200 –3. 12. Macario A, Weinger M, Carney S, Kim A. Which clinical anesthesia outcomes are important to avoid? The perspective of patients. Anesth Analg 1999;89:652– 8.