β-Adrenergic agonist infusion during extracorporeal lung perfusion: Effects on glucose concentration in the perfusion fluid and on lung function

Abstract

We recently showed in a pig model of ex vivo lung perfusion (EVLP) that lung edema correlates with glucose consumption. We investigated whether salbutamol, a β-adrenergic receptor agonist known to upregulate fluid transport in the lung, modulates glucose concentration in the perfusate during EVLP. Lungs from domestic pigs underwent normothermic EVLP. At the end of controlled reperfusion, lungs were ventilated and perfused for 60 minutes, then randomized to salbutamol (β-Agonist) infusion or placebo (Control) for 180 minutes. Functional parameters were assessed. In the β-Agonist group, glucose concentration decreased over time more than corresponding Control values (analysis of variance [ANOVA], p = 0.05). Mean pulmonary artery pressure (mPAP) was 16 ± 1 mm Hg in the β-Agonist group vs 21 ± 1 mm Hg in the Controls (ANOVA p < 0.05). Baseline mPAP was correlated with the drop of mPAP after the β-agonist infusion (R(2) = 0.856, p < 0.05). Dynamic compliance dropped from 51 ± 10 to 31 ± 6 ml/cm H(2)O in the β-Agonist group and from 60 ± 4 to 21 ± 3 ml/cm H(2)O in the Control group (ANOVA, p < 0.05 β-agonist vs Control). The Δ partial pressure of oxygen/fraction of inspired oxygen was 418 ± 15 and 393 ± 12 mm Hg in the β-Agonist and Control groups, respectively (t-test p = 0.106). Glucose concentration in the perfusate was affected by salbutamol. Salbutamol was associated with lower pulmonary pressures and better lung mechanics. These data suggest a possible role for salbutamol as a pharmacologic adjunct during EVLP before transplantation.