Biomaterial supports for colonic wall defect healing. An experimental study in the rat

Collagen patch cover facilitates recovery of bowel function after laparoscopic colectomy

BACKGROUND

Numerous factors can influence bowel movement recovery and anastomotic healing in colorectal surgery, and poor healing can lead to severe complications and increased medical expenses. Collagen patch cover (CPC) is a promising biomaterial that has been demonstrated to be safe in animal models and has been successfully applied in various surgical procedures in humans. This study.

METHODS

A retrospective review of medical records from July 2020 to June 2022 was conducted to identify consecutive patients who underwent laparoscopic colectomy. Patients who received CPC at the anastomotic site were assigned to the collagen group, whereas those who did not receive CPC were assigned to the control group.

RESULTS

Data from 241 patients (collagen group, 109; control group, 132) were analyzed. Relative to the control group, the collagen group exhibited a faster recovery of bowel function, including an earlier onset of first flatus (2.93 days vs. 3.43 days, p < 0.01), first defecation (3.73 days vs. 4.18 days, p = 0.01), and oral intake (4.30 days vs. 4.68 days, p = 0.04). CPC use was also associated with lower use of postoperative intravenous analgesics. The complication rates in the two groups did not differ significantly.

CONCLUSIONS

CPCs can be safely and easily applied to the anastomotic site during laparoscopic colectomy, and can accelerate bowel movement recovery. Further studies on the effectiveness of CPCs in colorectal surgery involving larger sample sizes are required.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov registration number: NCT05831956 (26/04/2023).

Collagen fleeces do not improve colonic anastomotic strength but increase bowel obstructions in an experimental rat model

PURPOSE

To investigate whether a collagen fleece kept in place by fibrin glue might seal off a colorectal anastomosis, provide reinforcement, and subsequently improve anastomotic healing.

METHODS

Wistar rats underwent a 1-cm left-sided colonic resection followed by a 4-suture end-to-end anastomosis. They were then randomly assigned to one of three treatment groups: no additional intervention (control, n = 20), the anastomosis covered with fibrin glue (fibrin glue, n = 20), the anastomosis covered with a collagen fleece, kept in place with fibrin glue (collagen fleece, n = 21). At either 3 or 7 days follow-up, anastomotic bursting pressure was measured and tissue was obtained for histology and collagen content assessment after which animals were sacrificed.

RESULTS

Three rats in the control (15%), three in the fibrin glue (15%), and one in the collagen group (4.8%) died due to anastomotic complications (P = 0.497). Anastomotic bursting pressures were not significantly different between groups at 3 and 7 days follow-up (P = 0.659 and P = 0.427, respectively). However, bowel obstructions occurred significantly more often in the collagen group compared to the control group (14/21 vs. 3/20, P = 0.003). Collagen contents were not different between groups, but histology showed a more severe inflammation in the collagen group compared to the other groups at both 3 and 7 days follow-up.

CONCLUSIONS

A collagen fleece kept in place by fibrin glue does not improve healing of colonic anastomoses in rats. Moreover, this technique induces significantly more bowel obstructions in rats, warranting further study before being translated to a clinical setting.

Evaluation of a collagen patch as a method of enhancing ventriculotomy healing in Japanese quail (Coturnix coturnix japonica)

OBJECTIVE

To assess the ability of a porcine submucosal collagen patch to enhance ventriculotomy healing in quail.

STUDY DESIGN

Histologic assessment of wound repair after ventriculotomy. Animal Population-Eighteen adult Japanese quail.

METHODS

All quail had a ventriculotomy through the caudoventral thin muscle. The quail were randomly assigned to 1 of 2 groups: group I (n = 9) had routine closure and group II (n = 9) had routine closure and the application of a porcine submucosal collagen patch over the serosal surface of the ventricular suture line. Three quail from each group underwent necropsy at 7, 14, and 21 days after surgery and healing of the ventriculotomy site was evaluated by microscopy.

RESULTS

Ventricular mucosal epithelium was completely healed at 21 days postoperatively. Time to restoration of the ventricular submucosal integrity was variable in both groups. There was evidence of a gross or microscopic perforation in 4 quail in group II, which was statistically significant (P =.041). Quail with perforations had significantly elevated numbers of ventricular serosal lymphoid aggregates compared with those without perforations (P =.029). There were no other significant temporal differences between group I and group II for mortality or histopathologic grading of wound healing.

CONCLUSIONS

A porcine collagen patch did not enhance ventriculotomy wound healing. Subjectively, the collagen patch might have contributed to perforation by the generation of a lymphocytic xenograft rejection response.

CLINICAL RELEVANCE

Ventriculotomy can be safely performed using routine closure methods in healthy birds.

Morphologic study and syntheses of type I collagen and fibronectin of human periodontal ligament cells cultured on poly(ethylene-co-vinyl alcohol) (EVA) with collagen immobilization

The purpose of this study was to regenerate the human periodontal ligament (PDL) around dental implants by using a hybrid structure of cells with materials, such as PDL cells + collagen + poly(ethylene-co-vinyl alcohol) (EVA) on titanium implant. Human PDL cells were cultured on the EVA surface coated with type I collagen and the cell adhesion and extension were investigated. Furthermore, collagen type I and fibronectin syntheses were analyzed. The serum free culture was also tried, to investigate the role of collagen in detail. The results showed that: 1. Satisfactory adhesion, extension, and proliferation of the PDL cells on the EVA films coated with collagen were observed, but were not good without collagen. 2. Immunostaining of cultured PDL cells revealed the syntheses of type I collagen, when cultured on the EVA coated with collagen or conventional culture dish, though fibronectin synthesis was observed even in the EVA without collagen. 3. Only PDL cells on the EVA coated with collagen proliferated well in the absence of serum. These results indicate that our novel implant material (EVA coated with collagen) provides a possibility of PDL regeneration on dental implants.