Propofol Sedation in Outpatient Colonoscopy by Trained Practice Nurses Supervised by the Gastroenterologist: a Prospective Evaluation of over 3000 Cases

Abstract

Propofol has several advantages for sedation in endoscopic procedures. Sedation administered by anaesthesiologists is associated with high costs. In this study the safety of propofol sedation administered by trained practice nurses under the supervision of the gastroenterologist in a cohort of outpatients of an ambulatory practice for gastroenterology in Germany is evaluated. During a period of 21 months all patients referred to colonoscopy were eligible for this prospective observational study. The familiar CRC risk of the individuals, indication, completeness and results of the colonoscopy were registered together with the dose of propofol used. Propofol was administered by intermittent intravenous bolus titration by trained practice nurses under supervision of the gastroenterologist. Oxygen saturation, heart rate and blood pressure were recorded constantly during the procedure and adverse cardiopulmonary events were monitored by the endoscopy team. A respiratory event was defined as an episode of apnoea or laryngospasm requiring assisted ventilation. 23 % of the patients received supplemental oxygen. A total of 3641 colonoscopies were recorded. 33 individuals were sedated with midazolam and were excluded from the evaluation. 3610 individuals were sedated with propofol (119 +/- 39 mg, mean dose +/- S. D.). 40 % of the procedures were performed as combined gastroscopy and colonoscopy. The cecum was reached in 99 % of the colonoscopies. Respiratory events occurred in five patients (0.14 %). Assisted ventilation in all cases was performed by mask ventilation. Bradycardia (HF < 60/min) and arterial hypotension (RR < 90 mmHg) occurred in 0.5 and 0.3 % of the colonoscopies, respectively, but medical intervention was necessary only in 0.2 % for both types of event. Minor events of hypoxaemia were observed in 51 patients (1.4 %), but only 1/3 of these events occurred in patients supplemented with oxygen. Propofol can be administered safely for ambulatory colonoscopy by trained practice nurses, with careful monitoring under supervision of the gastroenterologist.