Effect of preoperative respiratory muscle strength on the liver transplant outcome

Abstract

Purpose: To assess the effect of the preoperative respiratory muscle strength on the orthotopic liver transplantation (OLT) outcome. Methods: Maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax) were assessed in 228 recipients immediately before OLT. Patients were classified according to the occurrence of the absolute values of muscle strength equal or lower than 50 cm H₂O. The following response variables were analyzed: duration of postoperative mechanical ventilation, incidence of tracheal reintubation and noninvasive positive pressure ventilation, length of hospital stay, and patient survival. Results: PImax e PEmax were equal or lower than 50 cm H₂O in 19.7% (45/228) and 14.5% (33/228) of patients, respectively. The patient mortality up to 6 months after OLT was 14.2% (26/183) in the group with PImax > 50 cm H₂O and 33.3% (15/45) in the group with lower values (p=0.003). The 1-, 3-, and 5-year patient survival was 84%, 77% and 71% for the group with PImax > 50 cm H₂O and 57%, 50% and 50% for the group with lower values (p=0.0024). As to the PEmax, probabilities were 80%, 74% and 69% for the group with higher values and 66%, 59% and 51% for patients with respiratory muscle weakness (p=0.1039). There was no significant difference regarding others variables analyzed. Conclusion: Patients with low PImax present higher mortality rates after OLT. However, there are no statistically significant effects of the preoperative respiratory muscle strength on the response variables more directly related to the pulmonary outcome.