This prospective study demonstrates that propofol is a safe and effective agent for procedural sedation in the ED. The study also shows that propofol has a considerably shorter duration of action than midazolam, thereby shortening the period of sedation. Safe practice of procedural sedation requires two doctors, with one doctor acting as the sedationist and remaining with the patient until fully conscious.8,9
This has clear resource implications for the ED, which could be mitigated by reducing the duration of sedation. Although the shorter sedation time in our study did not produce a shorter overall length of time in the department, there were several potential reasons for this including prolonged time spent waiting for x
ray or inpatient bed availability.
A shorter duration of sedation with propofol has been reported in previous studies. Taylor et al1
compared propofol with midazolam/fentanyl in a randomised controlled trial of patients in an Australian ED for reduction of anterior shoulder dislocations. The authors titrated each drug to a clinical end point of spontaneous eye closure rather than use weight determined bolus doses. Patients in the propofol group had shorter mean times to first wakening and full consciousness, and had easier reductions; however, there were more episodes of respiratory depression (11 vs 6 patients) and one episode of vomiting. The high incidence of respiratory depression in the propofol group may have resulted from larger doses being given due to titration to spontaneous eye closure rather than using a weight‐determined bolus dose.
Low rates of adverse events have also been demonstrated in other studies. Swanson et al10
used a bolus of fentanyl with a propofol infusion to an end point of ptosis and slurred speech for a variety of procedures. They reported one transient episode of hypotension and two episodes of apnoea resolving within 30 s. The mean recovery time for patients was 6.1 min. Miner et al11
compared propofol with methohexital for fracture/dislocation reduction. Propofol was administered as a 1 mg/kg bolus then 0.5 mg/kg. The two agents were similar for duration of sedation (9.9 vs 8.5 min), level of sedation, and rate of adverse events. Coll‐Vincent et al12
compared propofol, etomidate, midazolam and midazolam plus flumazenil in patients undergoing cardioversion for atrial fibrillation or flutter and demonstrated a significantly shorter recovery time occurred with propofol group and midazolam/flumazenil group.
None of the patients in our study who received propofol were over‐sedated. However, four patients who all received large doses of midazolam (10–20 mg) were over‐sedated. This rate of over‐sedation is higher than that found in the recent study by Duncan et al
most probably due to the larger doses that were given, which were most likely the result of a failure to follow the departmental guidelines. The shorter duration of action of propofol makes titration of the dose easier than with midazolam. Symington and Thakore3
systematically reviewed the use of propofol for procedural sedation and concluded that propofol was safe and effective for procedural sedation.
The period of fasting was another area where the departmental guidelines may not have been followed, with seven patients receiving sedation after <4 h of fasting. The minimum period of fasting before emergency sedation is a contentious area. The recently published American College of Emergency Physicians Clinical Policy on sedation could find no evidence either way on a minimum period of fasting.14
Their level C recommendations stated that recent food intake was not a contraindication to procedural sedation in the ED.
There were several limitations to our study. We had lower than anticipated numbers enrolled into the study, possibly due to poor recruitment of patients, or poor identification of suitable patients for the study. Therefore the number recruited may not be large enough to detect all potential adverse events and reduces the ability for direct comparison between the two groups.
In conclusion, this study has shown propofol to be effective and safe for use in procedural sedation in the ED. Further work is required in the form of a randomised controlled trial comparing propofol and midazolam to study whether this shorter duration of action translates into a shorter length of stay in the ED.