Inclusion of ethyl nitrite in the insufflating gas can obviate the decreased tissue perfusion caused by prolonged carbon dioxide pneumoperitoneum

• Published in: Journal of the American College of Surgeons Vol. 199; no. 3; pp. 17 - 18
• Main Authors: Ken-ichiro, Uemura, McClaine, Rebecca J., Stamler, Jonathan S., Ahearn, Gregory S., Shimazutsu, Kazufumi, Lacassie, Hector J., McClaine, Deborah J., Campbell, Kurt A., Eubanks, W.Steve, Reynolds, James D.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01-09-2004
• ISSN: 1072-7515; 1879-1190
• DOI: 10.1016/j.jamcollsurg.2004.05.022

Introduction: Prolonged periods of carbon dioxide pneumoperitoneum (CO2-PNP) may produce intra-abdominal tissue ischemia and subsequent post-operative organ dysfunction. In a preliminary study we recently determined that ethyl nitrite (ENO), a nitric oxide congener, could improve liver blood flow during insufflation. The purpose of the present study was to evaluate the ability of ENO to attenuate the reduced tissue perfusion produced by prolonged CO2-PNP.
Methods: The study was conducted on appropriately anesthetized adult swine. Animals in the control group were insufflated with CO2 while experimental animals received CO2 plus a fixed concentration of ENO. PNP was maintained at a pressure of 15 mm Hg for 240 min during which respiration was actively managed to maintain end-tidal CO2 below 32. The microsphere technique was used to quantitate tissue perfusion before and during PNP. Differences in flow within each treatment group are expressed as percent of baseline.
Results: A total of 23 pigs were studied. Changes in splanchnic perfusion are presented in the table. For the CO2 alone group, reductions in vascular flow were noted after 60 min and flow remained depressed for the duration of the study. When ENO was included in the insufflation gas, perfusion significantly improved.
Tissue perfusion (% of baseline)
CO2 alone (n = 11)
CO2 + ENO (n = 12)
Region
180 min
240 min
180 min
240 min
Right hepatic
58 ± 16
72 ± 25
93 ± 8
97 ± 11
Portal venous inflow
81 ± 8
85 ± 9
122 ± 9
131 ± 9
Kidney cortex
69 ± 5
76 ± 6
85 ± 5
93 ± 5
Kidney medulla
65 ± 6
74 ± 8
77 ± 4
82 ± 6
Spleen
48 ± 8
47 ± 9
78 ± 9
85 ± 9
Conclusions: The data indicate that during prolonged CO2-PNP, ENO can effectively attenuate decreases (and in some areas increase) tissue perfusion within the peritoneal cavity. The dose-dependent effects of ENO and the implications of this finding on post-insufflation organ function are the foci of ongoing research.