Cardiopulmonary effects of the laparoscopic pneumoperitoneum in a porcine model of adult respiratory distress syndrome.

BACKGROUND

Increasingly, laparoscopy is being used in critically ill patients in whom there is a question of intra-abdominal sepsis. We examine the cardiopulmonary effects of laparoscopy in a porcine model of adult respiratory distress syndrome (ARDS).

METHODS

Domestic pigs (n = 12) underwent saline lung lavage and subsequent surgical abdominal exploration using either laparoscopy or conventional laparotomy. Hemodynamic and respiratory measurements were obtained.

RESULTS

After pulmonary lavage, the two groups developed similarly diminished arterial pO2 (P <0.001), a worsened pulmonary shunt (P <0.001), and an increased alveolar-arterial oxygen gradient (P <0.001). The pulmonary compliance was significantly decreased in the animals undergoing laparoscopy (versus laparotomy, P <0.05). The mean pulmonary arterial pressure did not differ between the groups. The laparoscopic group had a higher pCO2 (not significant) and was more acidotic (P <0.05) than the laparotomy group. The laparoscopic animals had an increased heart rate (P <0.05), cardiac index (P <0.01), and oxygen delivery (P <0.005) as compared with the laparotomy group.

CONCLUSIONS

During laparoscopy, animals with ARDS demonstrate further compromise in pulmonary physiologic parameters but overall cardio-respiratory function is preserved.