Low-Dose Ketamine in Combination with Midazolam for Diagnostic Upper Gastrointestinal Endoscopy: Case Report

Abstract

Introduction and objectives: The number of outpatient endoscopic procedures in gastroenterology has increased in recent years. During the pandemic, due to drug shortages, alternative sedation techniques were explored. This study describes the sedation profile and adverse effects of combining low-dose ketamine with midazolam for sedation during diagnostic upper gastrointestinal endoscopy (UGIE).

Materials and methods: A prospective, observational, descriptive case series study was conducted involving 30 patients aged 18 to 70 years with ASA physical status classification I or II, who underwent diagnostic UGIE. Sedation was induced with 0.03 mg/kg of midazolam and 0.3 mg/kg of ketamine prior to endoscopy. During and after endoscopy, the need for additional sedative medications and the occurrence of major adverse events (e.g., cardiorespiratory arrest or death) and minor events (e.g., desaturation, apnea, laryngospasm, hypertension, tachycardia, coughing, hypersalivation, dizziness, and recall of the procedure) were documented. Procedure duration, recovery time, and depth of sedation were also recorded.

Results: Effective sedation was achieved in 27 ASA I and II patients without the need for additional sedatives to achieve the endoscopic procedure. The mean procedure time was 7.9 minutes, and the average recovery time was 26.1 minutes. Adverse events were observed in 66% of patients during the procedure (the most frequent being elevated blood pressure in 45.9%) and in 63.4% during recovery (most commonly dizziness in 50%).

Conclusions: The combination of low-dose ketamine and midazolam appears to be a safe and effective sedation strategy for diagnostic UGIE, with minor adverse effects reported in more than 50% of patients.