Effect of increasing cardiac preload, sympathetic antagonism, or vasodilation on visceral blood flow during pneumoperitoneum.
OBJECTIVE
An impaired visceral perfusion caused by pneumoperitoneum may contribute to morbidity after laparoscopic surgery. The following three therapeutic concepts: increasing cardiac preload, controlled vasodilation, or selective sympathetic antagonism, were evaluated regarding a possible increase of visceral blood flow during pneumoperitoneum with carbon dioxide.


METHODS
Forty three pigs were assigned to treatment with an increase of preload and vasodilation (group A) or selective sympathetic antagonism with esmolol (group B). In both groups, pigs were assigned to head-up, head-down, or supine position. Perfusion of the vena porta and renal artery was measured by transonic volume flow meters and documented before capnoperitoneum, after induction of a 14-mmHg capnoperitoneum in each body position, after controlled vasodilation with sodium nitroprusside, and after controlled increase of intravascular volume by colloidal infusion.


RESULTS
Increasing intravascular volume improved portal blood flow in all body positions (p<0.05), but not renal blood flow. Medication of esmolol did not alter the measured parameters in any body position compared to control. Vasodilation with sodium nitroprusside reduced renal blood flow in supine and in head-up position.


CONCLUSIONS
An optimal intravascular volume was most effective in improving portal blood flow during capnoperitoneum in this trial. Esmolol had no negative effects on portal and renal blood flow. Patients with renal dysfunction might be treated carefully with sodium nitroprusside during capnoperitoneum.
Junghans
Tido
T
Department of General-, Visceral-, Vascular-, and Thoracic Surgery, Charité-University Medicine Berlin, Campus Mitte, Schumannstrasse 20/21, 10117 Berlin, Germany. tido.junghans@charite.de
Neudecker
Jens
J
Dörner
Felicitas
F
Raue
Wieland
W
Haase
Oliver
O
Schwenk
Wolfgang
W
D000818:Animals; D002245:Carbon Dioxide; D002302:Cardiac Output; D010535:Laparoscopy; D009599:Nitroprusside / Q000494:pharmacology; D011028:Pneumoperitoneum, Artificial; D011168:Portal System / Q000187:drug effects; D011412:Propanolamines / Q000494:pharmacology; D011897:Random Allocation; D012079:Renal Circulation / Q000187:drug effects; D018709:Statistics, Nonparametric; D013552:Swine; D014781:Viscera / Q000098:blood supply*
D011412:Propanolamines; D002245:Carbon Dioxide; D009599:Nitroprusside; C036604:esmolol