Effects of fluid resuscitation on cardiovascular performance after posttraumatic pneumonectomy.

BACKGROUND: : Several factors have been implicated in the high-mortality rate of posttraumatic pneumonectomy. In this study, we evaluated the hemodynamic and echocardiographic changes induced by pneumonectomy and fluid resuscitation after hemorrhagic shock. METHODS: : Fourteen dogs were bled to a target mean arterial pressure of 40 mmHg. The animals were assigned to two groups: control (no fluid resuscitation) and lactated Ringer's (3 x shed blood volume). The left pulmonary hilum was cross clamped, and the animals were observed for 60 minutes. Systemic hemodynamics was evaluated using Swan-Ganz, arterial catheter, and ultrasonic flow probe. Systemic O2-derived variables were calculated. Ejection fraction was determined by two-dimensional echocardiography. RESULTS: : Fluid resuscitation improved the mean arterial pressure and systemic oxygen delivery. After pneumonectomy, no significant increase in right ventricular pressure was observed in the LR group. No signs of major ventricular dilation or changes in arterial oxygenation were observed. CONCLUSION: : Our data suggest that pneumonectomy is not associated with early pulmonary hypertension; gentle fluid resuscitation improves cardiovascular performance and is not associated with an increase in right ventricular pressure.