When used under general anesthesia, propofol can cause severe respiratory depression and suppress the vomiting and cough reflex.

Respiratory depression also occurs during awake sedation induced by propofol.

Unlike benzodiazepines, propofol has no specific antagonist that can be used to reverse its effects.

The study, reported by Vargo et al. in the current issue of Gastroenterology, addresses some of these questions.

Their study was a randomized, prospective study in which 75 patients undergoing endoscopic retrograde cholangiopanthography (ERCP) or endoscopic ultrasound (EUS) received propofol or midazolam/pethidine administered by a gastroenterologist. The safety of this protocol was evaluated using CO2-graphy as the primary method for detecting early respiratory depression. Patient and endoscopist satisfaction with sedation was assessed using a visual analog scale, and any hangover effects of sedation were assessed over 24 hours by recording patient activity and food intake compared to baseline. A cost and cost-benefit analysis was performed to determine the differences between the 2 sedation regiments studied. Demographically and clinically, the two groups of patients were very similar. Standard measurements such as blood pressure and pulse oximeters were used during sedation, as well as electroencephalograms. Sedation (propofol or midazolam/pethidine) is performed by an independent physician.

Propofol is given in pill form rather than as a continuous infusion. Significant adverse events such as hypotension, hyperapnea, bradycardia, and hypoxemia during surgery were similar in both groups. Patients who received propofol took less time to reach sufficient sedation for intubation and recovered more quickly. All patients who received propofol were suitable for discharge within 30 minutes of surgery, compared to less than 20 percent of patients in the standard sedation group. Patients and endoscopists were more satisfied with propofol. There were significantly fewer sequelae of sedation assessed at 24 hours in the propofol group. The total cost was higher in the propofol group, but through a sensitivity analysis, the researchers concluded that if administered by a registered nurse rather than a doctor, the cost would be very similar to the cost of standard sedation.