# Abstract

 

## Background During laparoscopy, insufflation of an inert gas in the peritoneal cavity creates a working space to facilitate surgery. The space should be large enough to facilitate surgery without increasing intra-abdominal pressure (IAP) over a threshold limit (usually 15 mm Hg). 

## Objectives This experimental study was performed to evaluate the effects of increasing in intra-abdominal pressure on internal organs. 

## Materials and Methods Twenty female mixed breed dogs (20 ± 3 kg, 18 ± 1.2 months) were selected. They were randomly divided to two groups (n = 10). The intra-abdominal pressure was maintained 12 mm Hg and 20 mm Hg during the operation in control group and in test group respectively. 

## Results Histopathologic evaluations revealed more pathological changes at the kidney of all the dogs in test group in comparison to control group. 

## Conclusions Our findings revealed that organs that their blood supplies are related to one single or two arteries and their blood drainage are related to one or two veins are more sensitive to increased intra-abdominal pressure. # 4. Results There were no differences between dogs in body weight, age and the procedure of general anesthesia. In heart rate evaluation at equal intervals, no significant differences were observed over time between the two groups. Also in respiratory rate, there were no significant differences (P>0.05). Results of end tidal CO ~2~ measurements did not show severe hypoventilation during anesthesia in both groups. Comparison of this data between groups did not show any significant difference (P > 0.05). The mean of hemoglobin saturation measurements in the two groups did not show any significant difference (P > 0.05). Histopathologic evaluations revealed pathological changes at the kidney of all the dogs in test group (intraabdominal pressure: 20 mm Hg) ( [Figure 1](#) ) in comparison to control group (intra-abdominal pressure: 12 mm Hg) ( [Figure 2](#) ). These pathological changes included: coagulation necrosis, glomerulonephritis and fatty changes. Fatty changes were stronger at distal tubules in comparison with proximal tubules. The pathologic changes at the liver were similar in both groups and were mild. These changes included mild coagulation necrosis in the parenchyma, hyperplasia at the smooth muscles and congestion. The differences between two groups were not significant. The pathologic change that was significant in test group at the pancreases was acinar necrosis. This change was observed only in samples of test group. Any pathologic change at the spleen was not detected in two groups. <figure> <p><img src="" /></p> <figcaption>Pancreas Acinar Necrosis<br /> (a) normal acinar histological section of pancreas (control group), (b) acinar necrosis histopathological section of pancreas (test group; intraabdominal pressure: 20 mm Hg).</figcaption> </figure> <figure> <p><img src="" /></p> <figcaption>Kidney Histopathological Changes<br /> (a) Normal renal cortex histological section (control group), (b) necrosis of renal cortex (test group; intraabdominal pressure: 20 mm Hg), (c) normal medullary tubules (test group; intraabdominal pressure: 20 mm Hg), (d) more sever necrosis of renal cortex (test group; intraabdominal pressure: 20 mm Hg).</figcaption> </figure>


Extracted trial result:
Outcome: Pathologic changes in the liver (continuous)
Intervention: Intraabdominal pressure 20 mm Hg
Comparator: Intraabdominal pressure 12 mm Hg
Intervention group size: 10
Comparator group size: 10
Notes: No quantitative measures given