Cardiopulmonary changes during laparoscopy and vessel injury: comparison of CO2 and helium in an animal model.
BACKGROUND
Injury of venous vessels during elevated intraperitoneal pressure is thought to cause possible fatal gas embolism, and helium may be dangerous because of its low solubility.


METHODS
Twenty pigs underwent laparoscopy with either CO2 (n=10) or helium (n=10) with a pressure of 15 mm Hg and standardized laceration (1 cm) of the vena cava inferior. After 30 s, the vena cava was clamped, closed endoscopically by a running suture and unclamped again. During the procedure changes of cardiac output (CO), heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), pulmonary artery pressure (PAP), pulmonary artery wedge pressure (PAWP), end tidal CO2 pressure (PETCO2), and arterial blood gas analyses (pH, pO2 and pCO2) were investigated.


RESULTS
No animal died during the experimental course (mean blood loss during laceration: CO2, 157+/-50 ml; helium, 173+/-83 ml). MAP and CO values showed a decrease after laceration of the vena cava in both groups that had already been completely compensated for before suturing. PETCO2 increased significantly after CO2 insufflation (P<0.01), while helium showed no effect. Laceration of the vena cava caused no significant changes in PETCO2 values in either group. Significant acidosis and an increase of pCO2 were only found in the CO2 group.


CONCLUSIONS
The incidence of gas embolism during laparoscopy and accidental vessel injury seems to be very low. With the exception of acidosis and an increase of PETCO2 in the CO2 group, there were no differences in cardiopulmonary function between insufflation of CO2 and helium.
Jacobi
C A
CA
Department of Surgery, Humboldt--University of Berlin, Germany. christoph.jacobi@charite.de
Junghans
T
T
Peter
F
F
Naundorf
D
D
Ordemann
J
J
Müller
J M
JM
D000818:Animals; D002245:Carbon Dioxide; D004618:Embolism, Air / Q000209:etiology*; D006371:Helium; D006439:Hemodynamics; D022125:Lacerations; D010535:Laparoscopy / Q000009:adverse effects; D023421:Models, Animal; D011028:Pneumoperitoneum, Artificial; D011897:Random Allocation; D013552:Swine; D014682:Vena Cava, Inferior / Q000293:injuries
D002245:Carbon Dioxide; D006371:Helium