Plasma cholinesterase levels during cardiopulmonary bypass. A report on 10 cases

Plasma cholinesterase levels of 10 male patients were determined before, during and after cardiopulmonary bypass surgery. These levels dropped significantly below the pre-anaesthetic values after commencing anaesthesia. In 6 patients levels returned to pre-anaesthetic values before or on the 2nd postoperative day. This could not be explained in terms of enzymic biosynthesis alone, and it is suggested that postoperative fluid readjustments may play an important role in certain cases.