Effect of peri-operative red blood cell transfusion on 30-day and 1-year mortality following coronary artery bypass surgery

• Published in: European journal of cardio-thoracic surgery Vol. 27; no. 4; pp. 592 - 598
• Main Authors: Kuduvalli, Manoj, Oo, Aung Y., Newall, Nick, Grayson, Antony D., Jackson, Mark, Desmond, Michael J., Fabri, Brian M., Rashid, Abbas
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier Science B.V 01-04-2005; Elsevier Science
• Subjects: Aged; Biological and medical sciences; Cardiology. Vascular system; Coronary Artery Bypass - mortality; Coronary artery bypass grafting; Coronary heart disease; England - epidemiology; Epidemiologic Methods; Erythrocyte Transfusion - adverse effects; Erythrocyte Transfusion - mortality; Female; Haemoglobin; Heart; Humans; Male; Medical sciences; Middle Aged; Mortality; Perioperative Care - adverse effects; Postoperative Complications; Postoperative Period; Transfusion; England; Haemoglobin; Transfusion; Coronary artery bypass grafting; Mortality; Prognosis; Red blood cell; Cardiovascular disease; Coronary heart disease; Epidemiology; Treatment; Surgery; Hemoglobin; Graft; Day
• ISSN: 1010-7940; 1873-734X
• DOI: 10.1016/j.ejcts.2005.01.030

Objective: The purpose of this study was to examine the effect of peri-operative red blood cell (RBC) transfusion on 30-day and 1-year mortality following coronary artery bypass grafting (CABG). Methods: We retrospectively analysed 3024 consecutive patients who underwent isolated CABG between January 1999 and December 2001. Patient records were linked to the National Strategic Tracing Service, which records all mortality in the UK. Thirty-day and 1-year mortality were derived from Kaplan–Meier curves. Confounding variables were controlled for by constructing a propensity score for the probability of receiving a transfusion from core patient characteristics including the lowest recorded laboratory haemoglobin (LL Hb) from a clinical chemistry database (C statistic 0.81). The propensity score and the comparison variable (transfusion versus no transfusion) were included in a Cox proportional hazards analysis, allowing calculation of adjusted hazard ratios (HR) and Kaplan–Meier survival curves. Results: Nine hundred and forty (31.1%) patients received RBC transfusion during or within 72h of surgery. Predictors of the need for transfusion were LL Hb and lower body mass index, use of cardiopulmonary bypass, female sex, number of grafts, renal dysfunction, increased age, extent of disease, and prior CABG; these factors were all included in the propensity score. After 1-year of follow-up, 122 (4.03%) deaths occurred. The crude HR for 1-year mortality in patients transfused was 3.0 (P≪0.001). After adjusting for the propensity score, re-operation for bleeding, peri-operative blood loss and post-operative complications, the adjusted 30-day mortality was 1.9% in transfused patients compared to 1.1% in patients not transfused (P≪0.05). The adjusted HR for 1-year mortality in patients transfused was 1.88 (P≪0.01). Conclusions: Peri-operative RBC transfusion after CABG is associated with an increased risk of mortality during a 1-year follow-up period, with a large proportion of deaths occurring within 30-days.