Pulmonary Artery and Central Venous Pressures as Prognostic Indicators of Post Lung Transplant Outcome

Abstract

Background The relationship between elevated mean pulmonary arterial pressure (mPAP) and central venous pressure (CVP) on poor prognosis in patients undergoing lung transplants has been widely debated. We hypothesized that not only the isolated values of mPAP and CVP, but also the combination of discordant values in these variables may represent an unfavorable condition in lung transplantation. Methods We retrospectively reviewed 80 consecutive patients undergoing lung transplantation between 2008 and 2010. We investigated the relationship between of increased mPAP, CVP, and the discordance of the two variables (discordance group; DG vs. concordance group; CG) on the lowest PO2/FiO2 (P/F) ratio in the first 24 hours after admission to the ICU. We also assessed the impact of these indicators on ventilation time, ICU and hospital length of stay (LOS). Results Of the subjects in this study, 70 patients had bilateral lung transplantation, 40 were male, and the mean age was 51.2 (±14.5). All were intubated at ICU admission. For 1 mmHg increase in mPAP and CVP, the P/F ratio was 5.1 (95% CI 1.06, 9.12) and 8.48 (95% CI 2.89, 14.07) lower respectively. One mmHg increase in mPAP was also associated with hypoxia (defined as P/F ratio < 200), (OR 1.12; 95%CI 1.02-1.23), prolonged mechanical ventilation (MV) (>27hrs) (OR 1.13; 95%CI 1.02-1.25) and ICU LOS (>5 days) (OR1.19; 95% CI 1.06-1.33). One mmHg increase in CVP was also associated with prolonged ICU LOS (OR1.19; 95% CI 1.04-1.37). DG was associated with prolonged ICU LOS compared to CG (OR 6.95; 95% CI 1.37-35.23). Conclusion Post-operative mPAP, CVP as well as the interaction of the two have prognostic values in patients undergoing lung transplantation.