Remifentanil for Procedural Sedation in the Emergency Department

We are writing to present a case series cataloguing our experience with remifentanil as the sole agent for brief, painful procedures in the emergency department (ED). Although described as part of a combination technique, this is the first description of remifentanil as the sole agent for this purpose.1, 2

The ideal agent for procedural sedation cases has not been identified. Common practice includes a sedative-based technique with agents such as etomidate, propofol, or methohexital. Such techniques are often supplemented by modest doses of opiate but the sedative hypnotic agent exerts the primary effect. Pure opiate-based techniques are less well described.1

Remifentanil is a phenylpiperidine derivative with rapid action (1-2 minutes) and rapid hydrolysis by nonspecific plasma esterases with a clinical half life of 5-8 minutes. Like all phenypiperidines, remifentanil enjoys excellent hemodynamic stability.3, 4

A convenience sample was selected from patients requiring procedural sedation. Institutional procedural sedation guidelines were followed. An initial bolus dosage of 0.5 - 3 mcg/kg IV remifentanil was administered with subsequent 0.25 – 1 mcg/kg boluses as required. Patients were monitored with bispectral analysis (Aspect Medical Systems, Norwood, MA). Visual analog scales allowed patients to record procedural pain. Patients were queried regarding recall/unpleasant sensations. The operators recorded their opinion as to adequacy of sedation and analgesia. Time from last dosage of remifentanil to return of oriented speech was recorded.

Baseline data for the 12 patients included a mean age of 37 (range 18-77; standard deviation [SD] 17.2, 83% male). Comorbidities were rare with a mean ASA score of 1.7 (1-3; SD 0.7) and a mean baseline BIS of 97 (94-98; SD 1.2). A variety of procedures were performed with the majority being joint reductions. All procedures were completed successfully with a mean remifentanil dose of 3.4 mcg/kg (0.9-8.6; SD 1.9). Mean low bispectral analysis score was 84 (29-96; SD 18). Most patients recalled the procedure, with only one being unpleasant. Mean patient visual analog scale was 1.1 (0-3; SD 1.5). The quality of sedation and analgesia rated by the practitioner was consistently good or excellent. Two patients (17%) had complications requiring temporary intervention (one required bag-valve-mask ventilation and one required a laryngeal mask airway for 3 minutes). No patient had an adverse outcome. Mean time from final drug administration to full return of wakefulness was 4 minutes. Remifentanil doses in our cohort were directly correlated with degree of bispectral analysis depression.5

This is the first description of remifentanil as a single agent for procedural sedation in the ED. Our experience with remifentanil suggests that this agent may be extremely useful as a single agent for providing analgesia for brief, painful procedures. In summary: