Cholinesterase activity in serum during general anesthesia in health and disease

Atherosclerotic patients challenge the anesthesiologist as they display a significant instability between the two parts of the autonomic nervous system. We aimed to assess the effect of general anesthesia (GA) and surgery on serum cholinesterase activity. Prospective study of 57 patients undergoing ambulatory or vascular surgery under GA. Cholinesterase levels were measured before induction of anesthesia, 15 minutes thereafter and at the end of surgery by measuring the capacity of serum Acetylcholinesterase (AChE) and Butyrylcholinesterase to hydrolyze AcetylThioCholine. Data of atherosclerotic disease, anesthesia management were analyzed.Both AChE and total Cholinergic Status (CS) decreased significantly after GA induction at 15 minutes and furthermore by the end of surgery. Vascular surgery patients, presented lower baseline cholinesterase activity compared to patients for ambulatory surgery. In patients requiring intraoperative administration of phenylephrine for hemodynamic support (21.1%), a significant lower level of AChE and CS was observed compared to untreated patients. A positive correlation was found between the lowest temperatures measured and the AChE and CS change from the baseline values. Our findings serve as a mirror to the sympathetic/parasympathetic disbalance during GA with a marked decrease in the parasympathetic tone. Our data show that low cholinesterase activity increase the need for hemodynamic support.