Computer-controlled delivery versus manual delivery of propofol to produce general anaesthesia or sedation in adult patients

Continuous infusions of the intravenous anaesthetic propofol are commonly used to induce and maintain sedation and general anaesthesia. Propofol may be administered by a computer-controlled (target-controlled) or manually-controlled delivery system. Randomized trials have explored the differences in quality of anaesthesia, adverse event rate and propofol drug cost between the two types of delivery systems but their comparative effectiveness remains controversial. As computer-controlled delivery systems are in widespread international use, and potentially may be more expensive without added benefit, a systematic review of randomized controlled trials was warranted. After a search of the literature, 20 randomized controlled trials (RCTs) involving 1759 patients were selected for review. Eighteen studies focused on general anaesthesia and two studies focused on sedation. All papers were of poor methodological quality and there was high variability in the way outcomes were defined, measured and reported. Overall, target controlled infusion (TCI) was associated with higher total doses of propofol than manually controlled infusion (MCI), resulting in marginally higher propofol drug costs. However, fewer dose adjustments (interventions) were required by the anaesthetist during the use of TCI compared with MCI. With regard to quality of anaesthesia, recovery or adverse events (hypotension, apnoea, movement during anaesthesia), no clinically significant differences were demonstrated between treatment arms. No cases of unintentional awareness were reported. Effect size for total dose, induction dose, induction time, time to eye opening and movement during anaesthesia were highly variable because these outcomes depended on the infusion regimen used, which was different for every study. This systematic review does not provide sufficient evidence to make firm recommendations about the use of TCI versus MCI in clinical anaesthetic practice.