Cannabis adds work for anaesthetists — less than feared

A retrospective study covered 341,199 adults treated at one Boston medical centre. Recorded medical and non-medical cannabis use was associated with modestly higher doses of propofol and inhaled anaesthetics. The largest difference appeared among daily non-medical users: an additional 8.41 micrograms of propofol per kilogram per minute. The authors stress that the effects were smaller than previous estimates and their clinical relevance still needs testing; a very large table is still not a causal experiment.