The Optimal Tidal Volume Delivered by Ventilator after Pulmonary Resection: Its Effect on Cardiopulmonary Hemodynamics

Abstract

Pulmonary function and gas exchange deteriorate after pulmonary resection. The vital capacity, tidal volume, and functional capacity decrease after pulmonary resection becauce of loss of effective lung volume and, therefore, affect the setting of the ventilator. Nineteen patients undergoing pulmonary resection were included in this study on the optimal tidal volume delivered by a ventilator. Five patients received mediastinal surgery or wedge resection of the lung. 4 had pneumonectomy, and 10 had lobectomy. Immediately after the pulmonary surgery, they were maintained with ventilatory support. Subsequently, a different setting of tidal volume on the ventilator was given for each patient, i.e., 6 ml/kg, 8 ml/kg, 10 ml/kg, 12 ml/kg, and 14 mlikg. For each setting of tidal volume, a hemodynamic study was performed including cardiac output and other parameters. With the examination of Wilk's Lambda test, there was no difference in association with different settings of tidal volume on blood pressure ( F = 0.92, p = 0.51), pulrnonary artery pressure ( F = 0.95, p = 0.43), pulmonary vascular resistance (F = 0.24, p = 0.97), systemic vascular resistance (F = 0.42, p = 0.78). and cardiac output (F = 0.35, p = 0.93) in 3 different groups of patients.It is concluded that after pulmonary resection a patient's lungs can be inflated with a tidal volume to 14 ml/kg during ventilatory support without compromise of carcliovascular performance.Pulmonary function and gas exchange deteriorate after any major surgical procedure, particularly after pulmonary resection. The vital capacity, tidal volume, and functional residual capacity decrease after pulmonary resection because of loss of effective lung volume. No available literature mentions the difference between patients with and without pulmonary resection during mechanical ventilator support, especially about the delivery of tidal volume by the ventilator. The hemodynamic change for patients undergoing pulmonary resection was investigated in this study. The cardiac output, cardiac index, pulmonary artery pressure, and systemic and pulmoriary vascular resistance were evaluated under different settings of tidal volume in ventilatory ~~~~~ ~~ ~