Noninvasive positive pressure ventilation to prevent respiratory collapse after extubation: clinical case reports

Respiratory complications often develop in liver transplant recipients, and appropriate respiratory management is crucial to improve patient outcome. To evaluate the clinical usefulness of noninvasive positive pressure ventilation (NPPV) in liver transplant recipients, we established application criteria for NPPV in respiratory management in these patients, as follows: (1) arterial oxygen tension to fraction of inspired oxygen ratio less than 300 and arterial carbon dioxide tension greater than 45 mm Hg; (2) arterial oxygen tension to fraction of inspired oxygen ratio less than 200; (3) respiratory rate greater than 25/min; and (4) presence of severe atelectasis or pulmonary edema. A bilevel positive airway pressure ventilator was used with the pressure level adjusted to minimize patient discomfort. In patients who were not able to tolerate NPPV, it was discontinued. However, it was continued until patients no longer had dyspnea without NPPV or to resolution of the initial indication for NPPV such as hypoxemia, hypercapnia, or atelectasis. Of 36 patients who underwent liver transplantation between 2005 and 2007, NPPV was administered in 6 according to our criteria. After extubation, recipients demonstrated hypoxemia, hypercapnia, tachypnea, severe atelectasis, or pulmonary edema. After treatment, these conditions improved without apparent problems related to treatment with NPPV. In 1 patient, reintubation was required because of deterioration of respiratory function due to systemic infection. In conclusion, NPPV was useful in liver transplant recipients after extubation to prevent respiratory deterioration. For successful NPPV, settings must be individualized for each patient.