Ex vivo comparison of 7 polydioxanone, 2 polyglactin 910 for closure of ventral median celiotomy in horses.

This research article deals with the comparison of two types of sutures, namely USP 7 braided polydioxanone (7PD) and USP 2 polyglactin 910 (2PG), used to close a type of abdominal surgery (ventral median celiotomy) in horses. The study found that 7PD sutures had a greater resistance to bursting and were more robust compared to 2PG sutures.

Research Method

In this study, the following operational steps were applied:

• Ex Vivo Experiment: The experiment was carried out on fresh equine cadavers, providing a controlled environment where parameters could be precisely manipulated.
• Ventral Median Celiotomy: A 25 cm surgical incision was made in the midline of the horses’ abdomen to simulate a real-life surgical scenario.
• Suture Application: The surgical incisions were closed using two types of sutures – 7PD and 2PG – in a simple continuous pattern.
• Stress Test: A 200L polyurethane bladder was inserted into the abdomen and inflated with compressed air until the sutures failed, to examine their strength and durability.

Variables and Measurements

The study considered the following variables and measurements:

• The horses’ personal details, body weight, and suture type used were registered.
• The mode of failure (suture or abdominal wall) and bursting strength measured in mmHg were recorded for each suture type.
• Statistical tests – Linear regression was applied to assess the interactions between independent and dependent variables.

Key Findings

The findings of the research are as follows:

• Failure Modes: A significant difference was observed in failure modes by suture type. In cases where 2PG sutures were used, the sutures themselves were the failure point. Conversely, for celiotomies closed with 7PD, the abdominal wall was the point of failure, suggesting a stronger suture performance.
• Effect of Age: For 7PD sutures, a negative correlation was found with increasing age. That is, the burst strength of the 7PD sutures decreased as the age of the cadavers increased.
• Bursting Strength: After controlling for the effect of age, it was found that 7PD sutures had significantly higher bursting strength than 2PG sutures.

Conclusions

The research concluded that 7PD sutures exhibit higher bursting strength compared with 2PG sutures. Moreover, the main failure mode for 2PG was suture failure, whereas all failed cases using 7PD sutures were due to abdominal wall failure. This leads to the inference that 7PD sutures were stronger and more reliable in this context.