Benefits of non-invasive ventilation after extubation in the postoperative period of heart surgery

Abstract

Objective: to show the benefits of the use of non-invasive positive pressure ventilation (NPPV) in the process of weaning from mechanical ventilation in the immediate postoperative period of heart surgery. Methods: A prospective, randomized and controlled study was performed involving 100 consecutive patients submitted to coronary artery bypass grafting or valve surgery. The subjects were admitted into the Intensive Care Unit (ICU) under mechanical ventilation and randomized in a study group (n=50), which used NPPV with bilevel pressure for 30 minutes after extubation, and a control group (n=50) which only used a nasal O, catheter. Anthropometric variables and the times of the intra-operative periods corresponding to anesthesia, surgery and cardiopulmonary bypass, as well as the time required for weaning from invasive mechanical ventilation were analysed. The arterial blood gases and hemodynamic variables were also assessed before and after extubation. Results: The evolution was similar for the control and study groups without statistically significant differences of the variables analyzed except for the PaO2. On comparing the groups, the PaO2 improved significantly (p = 0.0009) with the use of NPPV for 30 minutes after extubation, but there was no statistically significant difference in the PaCO2 (p = 0.557). Conclusion: The use of NPPV for 30 minutes after extubation improved oxygenation in the immediate postoperative period of heart surgery. Descriptors: Heart surgery procedures. Intensive care unit. Respiration, artificial. Ventilator weaning. Intermittent positive-pressure ventilation.