High volumes of intravenous fluid during cardiac surgery are associated with increased mortality

摘要

Cardiac surgery, primarily coronary-artery bypass grafting (CABG), is commonly performed on a worldwide basis. The unadjusted mortality in the United States has decreased from last decade, however still remains high at 2.2% according to the Society of Thoracic Surgeons. A number of risk factors are associated with increased surgical mortality: age, female gender, serum creatinine, extra cardiac arteriopathy, chronic airway disease, severe neurological dysfunction, previous cardiac surgery, recent myocardial infarction, left ventricular ejection fraction, chronic congestive cardiac failure (CHF), pulmonary hypertension, active endocarditis, unstable angina, procedure urgency, critical preoperative condition [1]. Intra-operative hemodynamic abnormalities, including hypotension during and post cardiac surgery, pulmonary diastolic hypertension have also been shown to be independently associated with increased morbidity and mortality [2,3]. Most of the factors associated with increased mortality after cardiac surgeries are non-modifiable. Increased Intravenous Fluid (IVF) in non-cardiac surgery has been shown to be associated with increased morbidity and complications [4]. However, controversy still surrounds the type and regimen of fluids to be administered during cardiac surgery. Highly positive intra-operative fluid balance during cardiac surgery has been correlated with increased length of hospital stay and increased rates of Intensive Care Unit (ICU) readmission and blood transfusion [5]. We hypothesized that large administration of intravenous fluid during cardiac surgery is associated with increased 90 day mortality.