Procedural sedation of critically ill patients in the emergency department.

OBJECTIVES: Procedural sedation is routinely performed in the emergency department (ED). However, some authors believe it is unsafe in nonintubated, critically ill patients. The objective of this study was to determine the safety of ED procedural sedation in the American Society of Anesthesiologists (ASA) physical status classification P3 and P4 patients.

METHODS: This was a prospective observational study of patients undergoing procedural sedation in the ED between August 2002 and December 2003 who were classified as ASA physical status score P3 or P4. Patients received either propofol or etomidate at the discretion of the treating physician before their painful procedure. Doses, vital signs, end-tidal CO(2) (ETCO(2)) by nasal cannulae, and pulse oximetry were recorded. Respiratory depression (RD) was defined as a change from baseline ETCO(2) >10 mm Hg, an oxygen saturation of < 90%, or an absent ETCO(2) waveform at any time.

RESULTS: Sixty-two critically ill, nonintubated patients were enrolled. Thirty-one patients received propofol, and 31 patients received etomidate. No cardiac rhythm abnormalities were detected. RD was seen in 37 of 62 patients (59.7%): 19 of the 31 (61.3%) who received propofol and 18 of the 31 (58.1%) who received etomidate. The mean decrease from baseline systolic blood pressure was 11.3% (95% confidence interval [CI] = 7.3% to 15.5%): 5.0% (95% CI = 3.0% to 8.1%) for those receiving etomidate and 17.1% (95% CI = 9.9% to 24.3%) for those receiving propofol. No adverse events were reported.

CONCLUSIONS: The rate of subclinical RD detected by these criteria was similar to previous reports for noncritically ill patients. Procedural sedation of nonintubated ASA physical status score P3 and P4 patients in the ED with either propofol or etomidate appears to be safe.