Effects of increased intra-abdominal pressure on renal physiology in a rat model
Research field:Kidney physiology
Authors:Lindström P, Wadström J, Ollerstam A, JohnssonC, Persson A E G
Address of presenting
author:		Inst f Fysiologi
BMC Box 572
751 23 UPPSALA
E-mail:Pernilla.Lindstrom@fysiologi.uu.se
Phone:018-471 4319
Fax:018-4714938
Text of abstract Introduction
Prolonged increased intra-abdominal pressure, seen in laparoscopic surgery, is known to cause oliguria and anuria, probably due to changes in renal haemodynamics. Laparoscopic nephrectomies are performed though it is of outmost importance that the renal function is kept intact when the kidney is harvested for living donor transplantation. We wanted to establish a ratmodel to study if these effects on renal function are severe and how they can be avoided.

Methods
Male DA rats were organised into six groups. The groups were subjected to an intra-abdominal pressure (IAP) of 0 (control), 5 or 10 mmHg created by insufflation of CO2 for four or two hours. Three groups also received a bolusinjection of Candesartan. Urine output (UO) was measured as well as Na, K and osmolality in the urine. Also, glomerular filtration rate (GFR) was analysed and blood pressure monitored.

Results
Rats subjected to 10 mmHg showed a significant decrease in UO during the first two hours compared to the control group, while the group with an IAP of 5mmHg had a significant decrease in UO only during the first hour. Rats receiving Candesartan and high IAP had almost no urine production at all. GFR is affected in a similar manner. An interesting finding is that osmolality, Na as well as K in the urine falls significantly during high IAP.

Conclusions
These results show that the kidney function is altered by a high intraperitoneal pressure created by carbondioxide insufflation and that angiotensin has an important role in regulating blood pressure in our experiments. Further studies are needed in this area to elucidate the pathophysiological mechanisms and how they can be avoided.

References

Keywords:intraperitoneal pressure, renal function, living donor transplantation, laparoscopy

Created 2000-05-02