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

Abstract

Background: 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.

Methods: 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.

Results: 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).

Conclusions: 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.