High flow and high dose neosynephrine are effective to maintain perfusion pressure for the patient with preoperative angiotensin converting enzyme inhibitor during cardiopulmonary bypass

Angiotensin converting enzyme inhibitors (ACEIs) are widely used in the treatment of hypertension, myocardial infarction, and congestive heart failure. They have a known adverse effect of unresponsiveness to vasoconstrictors resulting in hypotension for the patients undergoing cardiac surgery. We report a case of a 43-year-old female patient with preoperative lisinopril (2.5 mg per day for a week prior to cardiac surgery), who was diagnosed with severe mitral and tricuspid valve regurgitation. She underwent both a mitral and tricuspid valve replacement operation using cardiopulmonary bypass (CPB). To address her ACEI-associated hypotension on cardiopulmonary bypass, bypass flows were as high as cardiac index of greater than 3 (3.1 +/- .2) L/min/m2 to provide sufficient perfusion indicated by cerebral oxymetry monitoring and adequate urine on pump. In addition, due to unresponsiveness to regular concentration of neosynephrine (neo), boluses of higher concentrations up to 320 microg/mL of neo were administered to maintain the perfusion pressure on pump. The patient was weaned from CPB uneventfully and was discharged home on postoperative day 7. Additional therapeutic treatment to ACEI-associated hypotension and unresponsiveness to neo for the patients undergoing cardiac surgery using CPB is reviewed as well in this paper.