A Model of Controllable Small Intestinal Obstruction Using New Zealand Rabbit

Objective To establish a stable rabbit model of controllable small bowel obstruction,the experiment can present good time-dependent relation and unification between the intestinal incarceration time and the degree of intestinal necrosis and recovery.Methods 52 adult healthy male New Zealand rabbits weighing 2.5~3.0 kg were divided into control group(4 rabbits) and model group(48 rabbits) randomly.The model group imitated controllable small bowel obstruction by making incarcerated abdominal wall hernia,which was that a midline fascial defect was made,the length of the defect was set by the 100 percent of the diameter of incarceration 10 cm-length bowel.By different intestinal incarceration and recovery time,the model group was divided into 8 groups randomly,including incarceration 2 h、4 h、6 h、8 h groups and releasing obstruction from the time point of irreversible intestinal damage 0 h、24 h、48 h、72 h groups.Using the sham operation group as the control group,the grade of intestinal injury among the groups was compared by necrosis degrees,and the statistic method was Ridit analysis.Results Comparing with the control group,the different degrees of intestinal necrosis were found in model group.The mean Ridit value of control group was 0.071;the mean Ridit value of each strangulated obstruction group from 2 h to 8 h was 0.327、0.545、0.735、0.890 respectively.Using LSD test of variance analysis,microscopic intestinal injury in each obstruction group was significantly different from the control group(P0.05);the significantly difference of intestinal injury was found between the obstruction groups(P0.05);Besides,the mean Ridit value of each releasing obstruction from the time point of irreversible intestinal damage(6h after obstruction) group from 0 h to 72 h was 0.774、0.595、0.443、0.222 respectively.Using LSD test of variance analysis,the significantly difference of intestinal injury was found between the releasing obstruction groups(P0.05).Conclusion This model of rabbit could present the process of controllable intestinal obstruction typically and show a time-dependent recovery degree when the block was released on time.