摘要：While the introduction of off-pump myocardial revascularization (OPCAB) has initially shown promise in reducing respiratory complications inherent to conventional coronary surgery, it has failed to eradicate them. Our study focused on quantifying the lactate release from the lungs and the dysfunction at the level of the alveolar-capillary membrane precipitated by OPCAB at different time points after the insult. Furthermore, we aimed to determine the impact of pulmonary lactate production on systemic lactic acid concentrations. The study was conducted in a prospective observational fashion. Forty consecutive patients undergoing OPCAB were analyzed. The mean patient age was 6010 years. The mean EUROScore was 3.82.9. The alveolar-arterial O2 gradient increased from 19 range 9 to 30 to 26 range 20 to 34 kPa (P observed increase in the pulmonary lactate release (PLR) from a baseline value of 0.022 range –0.074 to 0.066 to 0.089 range 0.016 to 0.209 mmol/min/m2 at six hours postoperatively did not reach statistical significance (P=0.105). The systemic arterial lactate (LS) concentration increased from 0.94 range 0.78 to 1.06 to 1.39 range 0.97 to 2.81 mmol/L (P in the studied group was 2.5% (1/40). The pulmonary lactate production showed a statistically significant correlation with the systemic lactate concentration (R=0.46; P=0.003). Pulmonary injury following off pump myocardial revascularization was evidenced by a prompt increase in the alveolar-arterial oxygen gradient. The alveolar-arterial O2 gradient correlated with the duration of mechanical ventilation.
