Congestive kidney failure in cardiac surgery: the relationship between central venous pressure and acute kidney injury

Acute kidney injury (AKI) in cardiac surgery has traditionally been linked to reduced arterial perfusion. There is ongoing evidence that central venous pressure (CVP) has a pivotal role in precipitating acute renal dysfunction in cardiac medical and surgical settings. We can regard this AKI driven by systemic venous hypertension as ‘kidney congestive failure’. In the cardiac surgery population as a whole, when the CVP value reaches the threshold of 14 mmHg in postoperative period, the risk of AKI increases 2-fold with an odds ratio (OR) of 1.99, 95% confidence interval (95% CI) of 1.16–3.40. In cardiac surgery subsets where venous hypertension is a hallmark feature, the incidence of AKI is higher (tricuspid disease 30%, carcinoid valve disease 22%). Even in the non-chronically congested coronary artery bypass population, CVP measured 6 h postoperatively showed significant association to renal failure: risk-adjusted OR for AKI was 5.5 (95% CI 1.93–15.5; P = 0.001) with every 5 mmHg rise in CVP for patients with CVP