EFFECTS OF PHENYLEPHRINE VS NORADRENALINE ON LACTATE LEVEL DURING CARDIOPULMONARY BYPASS IN PATIENTS UNDERGOING CORONARY ARTERY BYPASS GRAFTING
Objective: To evaluate effects of phenylephrine vs noradrenaline on lactate level during cardiopulmonary bypass in patients undergoing coronary artery bypass grafting.
Study Design: Comparative cross-sectional study.
Place and Duration of Study: Department of Anesthesia, Armed Forces Institute of Cardiology Rawalpindi Pakistan, from Jan to Jun 2019.
Methodology: A total of 200 patients, divided in two groups, group A and B, each consisting of 100 patients. Group A received phenylephrine and group B received noradrenaline, keeping mean arterial pressure between 65-90 mmHg. Serum lactate level was measured before induction, before initiation of cardiopulmonary bypass, after cooling, after rewarming and before shifting to ICU by collecting ABGs blood sample. Lac, Bicarbonate, PH, Hb and Base excess in patients at different time Points was measured. Data was stratified for age, gender, BMI and ASA class (II/III) to deal with effect modifiers. Post stratification
T-test was applied taking p-value ≤ 0.05 as significant.
Results: Lactate levels before induction were 1.30 ± 0.05 and 1.40 ± 0.04 in phenylephrine and noradrenaline groups with no statistically significant difference (p= 0.134). Lactate levels before cardiopulmonary bypass were 02.77 ± 1.82 and 03.83 ± 1.17 in phenylephrine and noradrenaline groups with no statistically significant difference (p=0.229). Lactate levels after cooling were 04.98 ± 01.67 in phenylephrine group and 06.11 ± 1.35 in noradrenaline group, with statistically significant difference (p= 0.003). Lactate levels after rewarming were 05.72 ± 01.85 in phenylephrine group and 07.17 ± 02.11 in noradrenaline group, with statistically significant difference (p=0.044). Lactate levels before shifting to ICU were 06.17 ± 02.43 in phenylephrine group and 07.52 ± 02.82 in noradrenaline group, with statistically significant difference (p=0.041).
Conclusion: Nor-adrenaline was associated with increase in the serum lactate levels more significantly as compared to phenylephrine in patients undergoing coronary artery bypass grafting via cardiopulmonary bypass.