Active spleno-femoral shunt avoids splanchnic congestion during portal triad occlusion: an experimental study.
Portal triad occlusion (PTO) is often performed during hepatic resections for trauma or malignancies to minimize intraoperative blood loss. The pringle maneuver is also regularly required during liver transplantation. This maneuver leads to temporary hepatic ischemia and may be associated with splanchnic blood flow congestion, promoting undesirable hemodynamic disturbances in some patients. Veno-venous bypass is a useful, easily performed technique that may avoid those deleterious hemodynamic effects of PTO. We tested the hypothesis that an active spleno-femoral shunt maintains hemodynamic stability and promotes complete decompression of the mesenteric bed, avoiding intestinal mucosal blood congestion, during PTO.


METHODS
Seven dogs (17.2 +/- 0.9 kg) were subjected to 45 minutes of hepatic ischemia during which there was an active spleno-femoral shunt. Systemic hemodynamics were evaluated through Swan-Ganz and arterial catheters. Splanchnic perfusion was assessed by portal vein blood flow and hepatic artery blood flow (PVBF and HABF, ultrasonic flowprobe), intestinal mucosal-arterial pCO(2) gradient (D(t-a)pCO(2), tonometry), and regional O(2)-derived variables.


RESULTS
No significant changes in systemic and regional parameters were observed during the ischemia period. During reperfusion, a significant decrease in mean arterial pressure, PVBF, and arterial pH was observed. A significant increase in ALT and D(t-a)pCO(2) (4.8 +/- 2.5 to 18.9 +/- 3 mm Hg) was also observed following hepatic blood flow restoration.


CONCLUSIONS
Spleno-femoral shunt maintains systemic hemodynamic stability, with an effective decompression of the splanchnic bed during portal triad occlusion. The deleterious hemodynamic and metabolic effects observed during reperfusion period, such as transitory hypotension, high D(t-a)pCO(2), and acidemia, were associated with an isolated hepatic ischemia-reperfusion injury, not with the blood congestion in the splanchnic bed.
Ribeiro
E A
EA
Division of Applied Physiology, Heart Institute/InCor, University of São Paulo Medical School, São Paulo, Brazil.
Cruz
R J
RJ
Poli de Figueiredo
L F
LF
Rojas
O
O
Rocha e Silva
M
M
D000818:Animals; D002407:Catheterization, Swan-Ganz / Q000379:methods; D004285:Dogs; D005263:Femoral Artery / Q000601:surgery*; D006439:Hemodynamics; D007511:Ischemia; D008102:Liver Circulation; D023421:Models, Animal; D011170:Portasystemic Shunt, Surgical; D015424:Reperfusion; D013162:Splenic Vein / Q000601:surgery*