Accelerated acute clonidine withdrawal syndrome during coronary artery bypass surgery. A case report.

A patient with essential hypertension treated with clonidine developed accelerated acute clonidine withdrawal syndrome during coronary artery bypass surgery. There were recurring hypotensive and hypertensive episodes. The hypotension was associated with myocardial ischaemia, cardiac arrhythmia and ventricular fibrillation, and was treated successfully with i.v. calcium chloride given at the onset of hypotension.