[Risk factors for acute respiratory failure after liver transplantation]

To study the risk factors for acute respiratory failure during recovery after liver transplantation.

We prospectively studied 340 consecutive liver transplant operations. Patient data was grouped according to whether acute respiratory failure developed (group I) or not (group II). Acute respiratory failure was defined by the need for mechanical ventilation longer than 5 days after transplantation or by the need for an inspired oxygen fraction of over 50% for 72 hours. We evaluated demographic characteristics, stage of liver disease before the transplant, comorbidity, immunosuppressant treatment administered, and complications during and after surgery.

Sixty-six patients were placed in group I and 274 in group II. Univariate analysis showed significant differences between the groups for age, sex, Child-Pugh functional stage, preoperative renal failure, type of immunosuppression, and postoperative complications such as atrial fibrillation, pleural effusion, pulmonary edema, ascites, postoperative acute renal failure, brain dysfunction, early graft dysfunction, and respiratory infection. Multivariate analysis by logistic regression, taking the development or not of acute respiratory failure as the dependent variable, gave a model with 6 variables that accounted for 94% of the cases. The variables entering into the model, with their respective odds ratios (OR) were female sex (OR, 5.5), stage C liver function (OR, 3.9), pulmonary edema (OR, 16.3), postoperative acute renal failure (OR, 9), cerebral dysfunction (OR, 4.5), and respiratory infection (OR, 62).

The development of acute respiratory failure after liver transplantation is affected by the following factors: female sex, Child-Pugh class, pulmonary edema, postoperative acute renal failure, cerebral dysfunction, and respiratory infection.