Pressure response of human colon to intraluminal distension (original) (raw)

Viscoelastic properties of the human colon

American journal of physiology. Gastrointestinal and liver physiology, 2001

Our objectives were to characterize colonic viscoelastic properties of the human descending colon by assessing pressure-volume (P-V) relationships during barostatic balloon distension. In 16 healthy subjects, a balloon was inflated to 44 mmHg and then deflated to 0 mmHg in 4-mmHg steps at 10, 30, and 60 ml/min, allowing volume fluctuations to stabilize at each pressure increment. Thereafter, these "quasi-static" P-V curves were compared with "dynamic" distensions to 300 ml, at 1 and 10 ml/s, before and after intravenous atropine in another five subjects. During quasi-static curves, balloon volume stabilized at each pressure increment. Quasi-static P-V curves were reproducible within individuals and approximated to a power exponential function and revealed hysteresis, indicative of viscoelasticity. Body mass index influenced quasi-static P-V curves during inflation but not during deflation. The colon was less compliant during dynamic distensions at 10 ml/s than du...

A Research Model of Measuring the Tensile Strength of Colonic Anastomosis in Wistar Rats

2014

The present experimental study investigates the mechanical behavior of intestinal anastomoses in Wistar rats. More specifically the response of the anastomoses to a properly applied uniaxial direct tensile load is studied and the respective tensile strength is determined. The surgical procedure of large bowel anastomoses is described in detail. In addition the authors provide a thorough description of the experimental apparatus, designed especially for measuring the tensile strength of the specimens under study, with special consideration in gripping of the intestine, the load application and the data acquisition and storage systems. This experimental model provides an excellent method for measuring the anastomotic strength and therefore a flexible tool for the comparative evaluation of various anastomotic techniques.