Optimizing Haemodynamics in Off Pump Coronary Artery Bypass Grafting: The Impact of Prophylactic Vasopressin Administration

Abstract

Objective: To evaluate the haemodynamic effects of prophylactic low-dose vasopressin in patients undergoing off-pump coronary artery bypass grafting (OPCAB).

Study Design: Quasi-experimental study.

Place and Duration of Study:  Department of Cardiac Anaesthesia, Armed Forces Institute of Cardiology/National Institute of Heart Diseases (AFIC/NIHD) Rawalpindi, Pakistan from Oct 2024 to Mar 2025.

Methodology: Seventy-six male and female patients, aged between 30 and 70 years, who were scheduled for elective OPCAB were included. Patients were divided into two groups of 38 patients. Group-A received Vasopressin (0.03 IU/min) and Group-B (control group) received Normal Saline, initiated during left internal mammary artery (LIMA) harvesting and continued until the end of surgery. Haemodynamic parameters i.e. mean arterial pressure (MAP), heart rate (HR), and central venous pressure (CVP) were recorded at key surgical stages. Lactate, creatinine, and CK-MB levels were measured at baseline, and 6 hours and 24 hours postoperatively.

Results: The overall cohort comprised 59.2% males with a mean age of 55.6 ± 8.1 years. During grafting, the Group-A maintained a higher MAP compared with Group-B (p ≤ 0.05) and a lower mean HR (p ≤ 0.05). No significant differences were observed in CVP or postoperative biochemical markers. Postoperative complications occurred in 21.05% of the Group-A and 28.95% of Group-B, a difference that was not statistically significant (p > 0.05).

Conclusion: Low-dose vasopressin improves intraoperative haemodynamic stability in OPCAB without adverse effects