Premedication, preparation, and surveillance.

Once again the staggering variation in IV sedation practice between different countries is highlighted. This year the "to sedate or not sedate" debate focuses on colonoscopy. Several papers on the use of Propofol are reviewed. It remains this authors' opinion that propofol is an anaesthetic agent to be used by (or at least in the presence of) an anaesthetist. Informed consent and the question of what to do if a patient withdraws consent halfway through the procedure are discussed. Predictably further recent papers on the relative merits of midazolam and diazepam are presented plus another report on the use of flumazenil in the recovery period. The use of 3% hydrogen peroxide solution to aid the visualization of acutely bleeding gastro-duodenal lesions is presented in two papers along with a discussion of its possible mode of action. The use of antispasmodics to aid colonoscopy is further discussed: this year concentrating on the use of hyoscyamine sulphate (as opposed to hyoscine butylbromide, the preferred agent in the UK). The patients receiving hyoscyamine sulphate had significantly shorter caecal intubation times, better sedation and easier colonic insertion. The "downside" was drug-induced tachycardia and the authors caution against the widespread use of this drug until this situation is further clarified. The subject of hypoxaemia at the time of gastroscopy, colonoscopy and ERCP was reviewed last year and further papers are presented in which the incidence of various levels of hypoxia are given. In anaesthetic circles it would be considered totally unacceptable to allow a patient's oxygen saturation to fall below 85 %, and yet we continue to have papers reporting its incidence. This level of desaturation is potential dangerous and the routine use of supplemental oxygen would greatly reduce this unneccessary risk to patients.