Factors determining blood transfusion in patients undergoing off pump coronary artery bypass graft (OPCABG) surgery: A prospective cross-sectional study

Abstract

Cardiovascular disease, especially coronary heart disease is increasing to a great extent globally and in India. Off pump Coronary artery bypass graft is one of the surgical modalities in the treatment of Coronary artery heart disease. Blood/ blood component transfusion is one of the essential roles during/immediate postoperative period of off pump coronary artery bypass graft surgery. Though there are few benefits due to blood transfusion, the demerits outweigh the merits of blood transfusion. Hence identification of predisposing factors for need of blood /blood component transfusions will enhance us to understand the indications and the ways to minimize it. To determine the predisposing factors that influence the need for blood transfusion during off pump coronary artery bypass graft and to measure their strength of association. This cross-sectional study was done in a tertiary care cardiac center in India between March and September 2016 on 196 patients. The participants were from both sexes, aged between 40-70 years, undergoing elective or emergency OPCABG under general anaesthesia. Information on Demographic data and comorbid illnesses were elicited. Vitals and other hemodynamic parameters were recorded during preoperative, intra operative and post operative periods. Total amount of anticoagulant (heparin) used, activated clotting time (ACT) after 3 minutes of anticoagulation, total duration of graft harvest (time from start of first graft harvesting to end of last graft harvest), total number of grafts taken, total duration for anastamoses (time from start of anastamosis to end of last graft anastamosis), total blood loss and total amount of blood transfused were noted. The intra-operative factors included total intra-operative heparin used, total protamine used, total number of grafts used for anastamoses, total duration of graft anastamoses, total duration of surgery, total duration of anaesthesia, total intra-operative blood loss and insertion of IABP intra-operatively. The post operative factors included total amount of postoperative blood loss and post operative insertion of IABP. Multivariate analysis of significant factors showed male gender, preoperative anaemia and total duration of surgery were independent predictors of need of blood and blood product transfusion. Prior identification of risk factors and correction of them if applicable would help to assess and manage preoperatively and also thereby reduce the need for blood transfusions and help in managing optimal utilization of resources.