Pulmonary artery catheter placement in high-risk coronary artery bypass grafting: should it be done before or after induction of anaesthesia?

Pulmonary artery catheter (PAC) is generally inserted after induction of general anaesthesia (GA). However, in high-risk coronary artery disease patients (left main disease / ejection fraction (35%), it may be desirable to insert it before the induction of GA. Thirty patients with left main coronary artery disease and / or left ventricular ejection fraction < 35% undergoing coronary artery bypass grafting (CABG) surgery were prospectively randomized into 2 groups of 15 each. In group A, pulmonary artery catheter was inserted before induction and in group B, after induction of GA. Haemodynamic parameters like heart rate (HR), mean arterial pressure (MAP), cardiac index (CI) and other derived parameters were obtained serially up to 10 min after tracheal intubation in group A and the haemodynamic management was based on these parameters. In group B, the haemodynamic management was based on HR and MAP. The demographic data was similar in both the groups. The time required for insertion of PAC was also similar in the two groups (7.6 +/- 1.8 and 6.2 +/- 1.3 min, p > 0.05). The number of interventions in the form of infusions of volume, nitroglycerin or dopamine were significantly more in group A before tracheal intubation. The patients in group A maintained better haemodynamics at 10 min after tracheal intubation as compared with group B (CI 2.8 +/- 0.67 vs 2.1 +/- 0.49, p < 0.05; stroke volume 54 +/- 18 vs 51 +/- 0.65, p < 0.05; systemic vascular resistance 1431 +/- 409 vs 1724 +/- 430, p < 0.05; pulmonary vascular resistance 109 +/- 34 vs 181 +/- 110, p < 0.05). Insertion of PAC before induction of GA provides informative data and can be utilized to treat haemodynamic alterations in high-risk patients undergoing CABG.