Establishing an animal model for peritoneal catheter malfunction caused by omental wrapping using negative pressure suction: and exploration.

Background: This study aims to establish a simplified and effective animal model of catheter malfunction caused by omental wrapped using negative pressure suction.

Method: The peritoneal dialysis catheter outlet was linked to a negative-pressure (0-75mmHg) suction pump to intensify the negative pressure. Different negative pressures were tested for model construction , a model of peritoneal catheter malfunction caused by omental wrapped was constructed in five beagles after catheter placement. Catheter drainage conditions and related complications were monitored before and after the model establishment.

Results: In the vitro experiment, the overall success rate of constructed models was 90% (36/40). The total malfunction rate was higher in 62.5 mmHg (10/10) and 75 mmHg (10/10) than in 12.5 mmHg (8/10) and 37.5 mmHg (8/10). The outflow velocity of dialysate at 62.5 mmHg was significantly lower than that at 12.5 mmHg and 37.5 mmHg, without a statistically significant difference compared to 75 mmHg. In the experiment, catheter outflow velocity increased, and residual fluid volume decreased after omental wrapped (99.6 ± 6.7 ml/min vs. 32.6 ± 4.6 ml/min at initial five minutes,  < 0.0001; 69.2 ± 16.3 ml vs. 581.0 ± 109.4 ml,  < 0.001). And the outflow velocity was finally below 2 ml/min. No severe related complications (such as infection, organ damage, or bleeding) were observed through laparoscopic examination and dialysate tests seven days post-operation.

Conclusion: Utilizing negative pressure suction to increase negative pressure around catheter tip is a simple, safe, and effective method for establishing an animal model of omental wrapped leading to catheter malfunction.