Preoperative Anemia Increases risk of Renal Dysfunction after Coronary ArteryBypass Surgery


  • Amer Iqbal Wazirabad institute of cardiology
  • Awais Alam Wazirabad Institute of Cardiology
  • Tipu Khan Wazirabad Institute of Cardiology
  • Javed Iqbal Rawalpindi Institute of Cardiology, Rawalpindi.


Anemia, Cardiac Surgery, CABG, Renal Dysfunction, Stroke


INTRODUCTION: Preoperative anemia is commonly encountered in patients undergoing coronary artery bypass surgery. It is now an established fact that anemia at the time of surgery affects the outcome. However, this fact has not been taken into account in the major cardiac surgery risk stratification systems. The impact of preoperative anemia on development of postoperative renal failure is not very well established. This study is planned to evaluate this effect. AIMS & OBJECTIVE: To assess the increases risk of renal dysfunction after Coronary Artery Bypass Surgery in patients having preoperative anemia. MATERIAL AND METHODS: This is a retrospective study, data extracted from the patient record operated at our institution between Jan 2019 to Feb 2021 for isolated stable coronary artery bypass surgery. A total of 819 patients were operated, final sample size of 773 patients was selected, 185 (24%) were anemic by world health organization definition of anemia. These patients and various parameters were then compared with non-anemic patients. RESULTS: Preoperative anemia was associated with three times increased risk of developing acute kidney injury or worsening of pre-existing renal dysfunction (18.3% vs 6.4% p<0.0001). There was also a significant difference in the anemic and no-anemic groups in developing postoperative stroke (2% vs 1% p=0.008), development of new onset atrial fibrillation (36.2% vs 32.9% p=0.003) and prolonged hospital stay (53.5% vs 35.8% p<0.0001). There was however no effect on postoperative myocardial infarction *2% in each group p=0.09). CONCLUSION: Preoperative anemia is a significant contributor to development of renal dysfunction, stroke and atrial fibrillation after coronary artery bypass surgery. KEYWORDS: Anemia, cardiac surgery, CABG, renal dysfunction, stroke

Author Biographies

Awais Alam, Wazirabad Institute of Cardiology

Chief Anaesthetist at Wazirabad Institute of Cardiology

Tipu Khan, Wazirabad Institute of Cardiology

Assistant Professor of Cardiac Surgery


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