HEMODYNAMIC-EFFECTS OF CARBON-DIOXIDE INSUFFLATION DURING THORACOSCOPY

As more complex thoracoscopic procedures are performed, adequate expos ure becomes increasingly more important. The insufflation of CO2 has b een demonstrated to aid in the compression of lung parenchyma and the effacement of subpleural lesions, and to act as a retractor when combi ned with changes in patient position. However, a recent study demonstr ated that CO2 insufflation during thoracoscopy in the pig had adverse hemodynamic consequences, We prospectively studied 32 patients undergo ing thoracoscopy to evaluate the effects of CO2 insufflation in the cl inical setting. The end-tidal CO2 pressure, arterial oxygen saturation , mean arterial pressure, heart rate, and central venous pressure were monitored. Measurements were determined at baseline, at the initiatio n of one-lung ventilation, and at intrapleural pressures of 2 to 14 mm Hg. We found that the insufflation of CO2 of 2 to 14 mm Hg had no sig nificant effect on the end-tidal CO2 pressure, arterial oxygen saturat ion, heart rate, or mean arterial pressure, but the central venous pre ssure did rise from 7.00 +/- 1.5 mm Hg to 17.30 +/- 2.53 mm Hg (p < 0. 05). We conclude from this that the insufflation of CO2 during thoraco scopy does not have adverse hemodynamic effects in the clinical settin g. Therefore, we propose that low-pressure (< 10 mm Hg) insufflation i s a safe adjunct to the conduct of routine thoracoscopic surgical proc edures.