Safety of propofol for conscious sedation during endoscopic procedures in high-risk patients-a prospective, controlled study

Propofol, a rapidly-acting hypnotic agent, is increasingly being used for endoscopic sedation. Serious adverse effects, including respiratory and cardiovascular depression, make many endoscopists reluctant to use propofol in critically ill patients. This study characterizes propofol's safety profile in consecutive high-risk patients (American Society of Anesthesiologists [ASA] classes III and IV) compared with matched subjects (ASA classes I and II).During a 19-month period, 1370 at risk-patients were sedated with propofol, of whom 47% (614 ASA III, 28 ASA IV) were age matched with 642 consecutive patients of the same gender and age assigned to ASA classes I and II and undergoing the same endoscopic procedures (395 gastroscopies, 201 colonoscopies, 14 combined). Registered nurses performed all sedations by propofol dose titration while carefully monitoring arterial oxygen saturation, heart rate, and blood pressure.No major complications occurred among the critically ill patients. There was, however, an increased risk for a short relevant oxygen desaturation (90%) of 3.6% for ASA III and IV versus 1.7% for ASA I and II (p = 0.036). In four versus one case, short mask ventilation was necessary. Also, a greater proportion of patients showed aor =5% oxygen saturation decrease. There was no pronounced influence on arterial pressure or heart rate and no perforations in 336 colonoscopies.With careful monitoring, propofol sedation during GI endoscopies is safe, even for high-risk patients. Considering their higher comorbidity and tendency toward oxygen desaturation, they need particularly careful monitoring, and the required dose is, on mean, 10-20% lower than in ASA classes I and II.