Pressure-regulated volume control vs volume control ventilation in infantsafter surgery for congenital heart disease

The objective of this investigation was to compare how two modes of positiv e pressure ventilation affect cardiac output, airway pressures, oxygenation , and carbon dioxide removal in children with congenital heart disease in t he immediate postoperative period. The investigation used a one group prete st-post-test study design and was performed in the pediatric cardiac intens ive care unit in a university-affiliated children's hospital. Nine infants were enrolled immediately after repair of tetralogy of Fallot (2) or atriov entricular septal defects (7) with mean weight = 5.5 kg (4.2-7.3 kg). Child ren were admitted to the pediatric cardiothoracic intensive care unit after complete surgical repair of their cardiac defect and stabilized on a Sieme n's Servo 300 ventilator in volume control mode (VCV1) (volume-targeted ven tilation with a square flow wave pattern). Tidal volume was set at 15 cc/kg (total). Hemodynamic parameters, airway pressures and ventilator settings, and an arterial blood gas were measured. Patients were then changed to pre ssure-regulated volume control mode (PRVC) (volume-targeted ventilation wit h decelerating flow wave pattern) with the tidal volume set as before. Meas urements were repeated after 30 minutes. Patients were then returned to Vol ume control mode (VCV2) and final measurements made after 30 minutes. The m easurements and results are as follows: [GRAPHICS] PIP, peak inspiratory pressure: P-aw, mean airway pressure; CI, cardiac ind ex. *p <0.05. After correction of congenital heart defects in infants, mechanical ventila tion using a decelerating flow wave pattern resulted in a 19% decrease in p eak inspiratory pressure without affecting hemodynamics, arterial oxygenati on, or carbon dioxide removal.