Background/aims: This study was designed to determine whether there exists a difference between in vivo and in vitro measurements of bursting pressure (BP) of experimental intestinal anastomosis studied in Wistar-albino rats.
Methodology: In the first group (n=8), the BP was measured using in vivo method without detaching the adhesions around the anastomosis. BP was determined with digital manometer, and then anastomotic region was removed to measure tissue hydroxyproline (HP) levels. In the second group (n=8), the BP was measured with in vitro method after the segment of intestine including the anastomosis was dissected and isolated. The isolated specimen was then submerged in a normal saline bath. BP was determined with a digital manometer and anastomotic region was removed to measure tissue HP levels.
Results: While HP value in the first group was 105.60 +/- 9.43 microg/mg dry tissue, it was found to be 121.11 +/- 16.26 microg/mg dry tissue in the second group and this difference was not statistically significant (p=0.195). The BP was determined as 240.71 +/- 11.65 mmHg in the first group, 144.71 +/- 16.41 mmHg in the second group and the difference was statistically significant (p=0.002). The anastomotic resistances to intraluminal pressure were found to be statistically different whereas tissue HP levels were normal between the groups.
Conclusions: These results make us consider that mechanical changes occur about the isolated anastomotic line and dissection of adhesions weakens the anastomosis.