The effectiveness of a low-dose esketamine versus an alfentanil adjunct to propofol sedation during endoscopic retrograde cholangiopancreatography

BACKGROUND Endoscopic retrograde cholangiopancreatography (ERCP) is one of the most complex gastrointestinal endoscopic procedures. Currently, it is still unclear which sedation regimen best facilitates an ERCP. The N -methyl- d -aspartate receptor antagonist esketamine has anaesthetic, analgesic and sympathomimetic properties and is known to cause less cardiorespiratory depression than other sedatives. It could therefore be an ideal adjunct to propofol for deep sedation. OBJECTIVE To assess the effectiveness of esketamine versus alfentanil as an adjunct to propofol target-controlled infusion (TCI) for deep sedation during ambulant ERCP. DESIGN A randomised controlled multicentre study. SETTING Endoscopic intervention suite at an academic and general hospital in the Netherlands. PARTICIPANTS Adult, American Society of Anesthesiologists Physical Status I to III patients scheduled to undergo ERCP. INTERVENTION Consecutive patients were randomly assigned to receive sedation for an ERCP with propofol TCI and alfentanil (group A) or with propofol TCI and esketamine (group E). MAIN OUTCOME MEASURES The primary outcome was effectiveness of the sedation regimen expressed as the total dose of propofol – as a surrogate parameter – necessary to perform ERCP in a satisfactory manner for endoscopist and patients. Secondary outcomes were recovery time, patients’ and endoscopists’ satisfaction with sedation, side effects (e.g. psychotomimetic effects, nausea and vomiting) and the number of respiratory and cardiovascular adverse events. RESULTS Data from 162 patients were analysed. The total dose of propofol required was significantly lower in group E ( n =83) (8.3 mg kg −1 h −1 ) than in group A ( n =79) (10.5 mg kg −1 h −1 ) ( P < 0.001). There were no significant differences in recovery time, patients’ and endoscopists’ satisfaction, side effects, psychotomimetic effects and the number of sedation-related adverse events. CONCLUSION Low-dose esketamine reduces the total amount of propofol necessary for sedation during ERCP in American Society of Anesthesiologists I and II patients without affecting recovery time, satisfaction of patients and endoscopists, side effects and respiratory or cardiovascular adverse events, when compared with alfentanil. TRIAL REGISTRATION The Netherlands Trial Register (NTR5486).