Nuevas perspectivas en trasplante de pulmón

Abstract

Two of the complications that have the greatest impact on survival after lung transplantation (LT) are primary graft dysfunction (PGD) and respiratory infections. This thesis includes two studies on these complications._x000D_ The first of these studies analyzed the role of the biomarker proadrenomedullin (proADM) in PGD. The objective was to assess the association between proADM plasma levels (measured by immunofluorescence) in the first three days after surgery and graft function [defined by the partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FIO2) ratio], the different degrees of PGD and mortality in the intensive care unit (ICU). In this prospective study including 100 LT recipients admitted to the ICU after surgery, a significant association was confirmed between the biomarker levels and the PaO2/FIO2 ratio in the first three days. Proadrenomedullin levels measured at 24 hours were significantly higher in the population of patients who presented grade 3 PGD at 72 hours, the only degree associated with increased ICU mortality. Proadrenomedullin levels measured at 48 and 72 hours were significantly higher in patients who died in the ICU. Finally, adding the individual predictive utility for ICU mortality of grade 3 PGD at 72 hours to that of proADM measured at 72 hours improved the model’s predictive value. The conclusion was that higher proADM levels measured following LT are associated with the most severe grade of PGD and with early mortality. These findings may have implications for prognosis in LT recipients and may also be relevant to future research works into PGD._x000D_ The second study assessed the impact of respiratory infections in the immediate postoperative period after LT. The main objective was to evaluate the effect of ventilator-associated pneumonia (VAP) and tracheobronchitis (VAT) on ICU and hospital length of stay and on early mortality. Secondary objectives were to identify their causative organisms and their potential risk factors. A retrospective study was designed in which the clinical data of 170 consecutive LT recipients admitted to the ICU after surgery were analyzed. Suffering ventilator-associated respiratory infection was associated with more days of mechanical ventilation and with longer ICU and hospital stays. Mortality in the ICU was higher in patients who had VAP, but not in patients with VAT. Pseudomonas aeruginosa was the most frequent germ causing ventilator-associated respiratory infection. In the VAP cases, 8/12 were multidrug resistant. The multivariate analysis showed that gastric paresis was an independent risk factor for the development of VAP, an association that remained significant when adjusting for days of mechanical ventilation. Further, both gastric and phrenic paresis were risk factors for the development of VAT. In conclusion, prevention of VAP following LT may reduce early mortality. The empirical treatment of ventilator-associated respiratory infections should cover multidrug resistant pathogens. Finally, prevention of gastroparesis may reduce the incidence of VAP and prevention of phrenic paresis may reduce the incidence of VAT.

Date of Award	27 Nov 2015
Original language	Undefined/Unknown
Awarding Institution	Vall d'Hebron University Hospital (HUVH)
Supervisor	Teresa Pont Castellana (Director), Ferran Morell Brotad (Tutor) & Jordi Rello Condomines (Director)