PERIOPERATIVE CHANGES IN PLASMA BRAIN NATRIURETIC PEPTIDE CONCENTRATIONS IN PATIENTS UNDERGOING CARDIAC-SURGERY

The plasma concentrations of brain natriuretic peptide (BNP), a cardia c hormone, were measured in 30 consecutive adult patients undergoing c ardiac surgery with cardiopulmonary bypass (CPB) during the perioperat ive period. BNP concentrations remained unchanged until 6 h after the cessation of bypass, and were elevated 12, 24, and 48 h post-bypass (P < 0.0001 versus baseline). They had returned to the baseline values w hen measured 3 weeks postoperatively, The preoperative plasma BNP conc entration correlated significantly with the left ventricular ejection fraction (r = -0.895), The peak plasma BNP concentration 24 h after by pass correlated with the cardiac index (r = -0.64), stroke volume inde x (r = -0.62), injection rate of dopamine hydrochloride (r = 0.65), an d aortic crossclamp time (r = 0.57), There was also a significant corr elation between the preoperative BNP concentration and tile plasma BNP concentration 24 h post-CPB, These findings led us to conclude that t he plasma concentrations of BNP become markedly and acutely elevated a fter cardiac surgery with CPB, and reflect the state of left ventricul ar function, Moreover, the severity of acute heart failure after cardi ac surgery can be predicted by the preoperative plasma BNP concentrati on.