The hemodynamic effects of CO2-induced pressure on the kidney in an isolated perfused rat kidney model.

Division of General Surgery B, Tel Aviv Sourasky Medical Center, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Surgical laparoscopy, endoscopy & percutaneous techniques (Impact Factor: 0.88). 12/2008; 18(6):573-8. DOI: 10.1097/SLE.0b013e3181875ba4
Source: PubMed

ABSTRACT Variable mechanisms were suggested to mediate the changes in renal hemodynamics during pneumoperitoneum. To assess whether it can be pressure dependent only, we conduct a study in an isolated, pressurized, and perfused organ model.
Seventy Wistar rat kidneys were perfused with oxygenated, 3% albumin-contained Krebs-Henseleit solution. Experiments took place within Plexiglass chamber that provided conditions for perfusion of organs, humidity, and maintenance of intracameral CO2 pressures [0 (control), 3, 5, 8, 12, 15, and 18 mm Hg]. All kidneys (10/group) were perfused for 60 minutes. One-half of the groups were perfused for an additional 30 minutes, during which the perfusion pressures were reduced to 0 mm Hg. pH of the perfusate was measured as well.
The perfusion pressure increased and the kidney flow decreased slightly, in proportion with the intrachamber pressure. Urine output decreased to a minimum of 40% in >or=8 mm Hg pressure conditions, compared with the control group. The pH values were below normal, during experimental pneumoperitoneum.
Pneumoperitoneal conditions are a direct cause of changes in renal urinary output. The increase in pCO2 pressure and consequently low intraorgan pH may contribute to a mild transient renal damage during pneumoperitoneum.

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