Effects of sodium hypochlorite and ozone on healing of intestinal anastomosis in simulated strangulation colorectal obstruction

Experimental models of high-risk bowel anastomosis in rats: A systematic review

BACKGROUND

Anastomotic leaks remain one of the most dreaded complications in gastrointestinal surgery causing significant morbidity, that negatively affect the patients' quality of life. Experimental studies play an important role in understanding the pathophysiological background of anastomotic healing and there are still many fields that require further investigation. Knowledge drawn from these studies can lead to interventions or techniques that can reduce the risk of anastomotic leak in patients with high-risk features. Despite the advances in experimental protocols and techniques, designing a high-quality study is still challenging for the investigators as there is a plethora of different models used.

AIM

To review current state of the art for experimental protocols in high-risk anastomosis in rats.

METHODS

This systematic review was performed according to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. To identify eligible studies, a comprehensive literature search was performed in the electronic databases PubMed (MEDLINE) and Scopus, covering the period from conception until 18 October 2023.

RESULTS

From our search strategy 102 studies were included and were categorized based on the mechanism used to create a high-risk anastomosis. Methods of assessing anastomotic healing were extracted and were individually appraised.

CONCLUSION

Anastomotic healing studies have evolved over the last decades, but the findings are yet to be translated into human studies. There is a need for high-quality, well-designed studies that will help to the better understanding of the pathophysiology of anastomotic healing and the effects of various interventions.

The acute effects of preoperative ozone theraphy on surgical wound healing

PURPOSE

To investigate the effects of preoperative rectal ozone insufflation on surgical wound healing over the proinflammatory cytokines and histopathological changes.

METHODS

Twenty one rabbits were divided into 3 groups. Sham, surgical wound, and ozone applied (6 sessions, every other day 70 µg/mL in 12 mL O2-O3 mixture rectally) surgical wound groups were created. TNF-alpha and IL-6 levels from all rabbits were studied at the basal, 24th hour, and 72nd hour. The histopathological examination was done by removing the surgical scar tissue at the end of 72nd hour.

RESULTS

TNF-alfa and IL-6 levels were significantly lower compared to the control group, in the rabbits treated with ozone. The increase in angiogenesis, the decrease in the number of inflammatory cells, epidermal and dermal regeneration, better collagen deposition, and increased keratinisation in stratum corneum were observed in the histopathological examination. It was determined that the wound healing noticeably accelerated in the ozone group.

CONCLUSION

Preoperative rectal ozone insufflation had a positive effect on surgical wound healing in acute period.

Effect of ozone on intestinal epithelial homeostasis in a rat model

BACKGROUND

The positive effects of ozone therapy have been described in many gastrointestinal disorders. The mechanisms of this positive effect of ozone therapy are poorly understood. The purpose of the present study was to investigate whether the use of ozone may potentiate the gut intestinal mucosal homeostasis in a rat model.

METHODS

Adult rats weighing 250-280 g were randomly assigned to one of three experimental groups of 8 rats each: 1) Control rats were given 2 mL of water by gavage and intraperitoneally (IP) for 5 days; 2) O3-PO rats were treated with 2 mL of ozone/oxygen mixture by gavage and 2 mL of water IP for 5 days; 3) O3-IP rats were treated with 2 mL of water by gavage and 2 mL of ozone/oxygen mixture IP for 5 days. Rats were sacrificed on day 6. Bowel and mucosal weight, mucosal DNA and protein, villus height and crypt depth, and cell proliferation and apoptosis were evaluated following sacrifice.

RESULTS

The group of O3-IP rats demonstrated a greater jejunal and ileal villus height and crypt depth, a greater enterocyte proliferation index in jejunum, and lower enterocyte apoptosis in ileum compared to control animals. Oral administration of the ozone/oxygen mixture resulted in a less significant effect on cell turnover.

CONCLUSIONS

Treatment with an ozone/oxygen mixture stimulates intestinal cell turnover in a rat model. Intraperitoneal administration of ozone resulted in a more significant intestinal trophic effect than oral administration.

Effect of Ozone Therapy (OT) on Healing of Colonic Anastomosis in a Rat Model of Peritonitis

BACKGROUND

Ozone is a three-oxygen molecule (O3). Ozone therapy (OT) is systematically effective when pathological inflammatory and immunologic processes are activated. Among of these conditions are wound healing, macular degeneration related to aging, and conditions that are ischemic or infectious.

AIMS

The aim of this study was to determine the effects of OT on wound healing of intestinal anastomosis in the presence of peritonitis in a rat model.

STUDY DESIGN

Animal experimentation.

METHODS

A total of 40 Wistar albino rats were randomized into four groups (n=10) including: sham (S), peritonitis (P), ozone 0 (O0), and ozone 24 (O24). In group S, only cecal dissection was carried out. The S group had only a cecal dissection and intestinal anastomosis performed, but no peritonitis. In all other groups, cecal ligation and puncture (CLP) followed the cecal dissection to induce bacterial peritonitis. 24 h after puncture, a cecal resection and ileocolic anastomosis were performed. In group P, 24 h after CLP, a cecal resection and ileocolic anastomosis were performed and no ozone was administered. In group O0, immediately after the anastomosis, and in group O24, starting 24 hours after the anastomosis, an intraperitoneal 1 mg/kg/day ozone administration was applied for seven days. On the seventh day the animals were sacrificed, the anastomotic bursting pressures (BP) and the hydroxyproline values of the anastomotic tissues were measured, and histopathologic examination of the anastomotic segment was carried out.

RESULTS

The highest BP was in group S, with 211±23.13 mmHg. The mean BP of group P was 141±56.25 mmHg, which was significantly lower than in the other two peritonitis groups that received ozone therapy, group O0 and O24, where it was 192±22 and 166±45 mmHg, respectively (p<0.05). The difference in the BP between groups O0 and O24 was not statistically significant (p>0.05). Histopathologic analyses of the anastomotic segments determined there was significantly more oedema and necrosis in the control group rats, and collagen deposition in the anastomotic tissue was significantly higher in the ozone-treated groups on postoperative day 7. Hydroxyproline levels were significantly higher in groups O0 and O24 compared to the peritonitis group (P).

CONCLUSION

Ozone therapy has a beneficial effect on anastomotic healing of the colon in the presence of peritonitis.

Effect of ozone on intestinal recovery following intestinal ischemia-reperfusion injury in a rat

BACKGROUND

Growing evidence suggests that ozone (O3) protects the host against pathological conditions mediated by reactive oxygen species by increasing the activity of antioxidant enzymes. The purpose of the present study was to examine the effect of O3 on intestinal recovery and enterocyte turnover after intestinal ischemia-reperfusion (IR) injury in rats.

METHODS

Male Sprague-Dawley rats were divided into four experimental groups: (1) sham rats underwent laparotomy; (2) sham-O3 rats underwent laparotomy and were treated with an ozone/oxygen mixture intraperitoneally and intraluminally (50 %/50 %); (3) IR rats underwent occlusion of both superior mesenteric artery and portal vein for 20 min followed by 48 h of reperfusion, and (4) IR-O3 rats underwent IR and were treated with an ozone/oxygen mixture similar to group 2. Intestinal structural changes, Park's injury score, enterocyte proliferation and enterocyte apoptosis were determined 48 h following IR. Western blot was used to determine ERK and Bax protein levels. A non-parametric Kruskal-Wallis ANOVA test was used for statistical analysis with p < 0.05 considered statistically significant.

RESULTS

Treatment of IR rats with O3 resulted in a significant increase in mucosal weight in jejunum (70 %) and ileum (32 %), mucosal DNA (twofold increase) and protein (35 %) in ileum, villus height and crypt depth in jejunum (61 and 16 %, correspondingly) and ileum (31 and 43 %, correspondingly) compared to IR animals. IR-O3 rats also had a significantly lower intestinal injury score as well as a lower apoptotic index in jejunum and ileum compared and IR animals. A significant increase in cell proliferation rates in IR-O3 animals was accompanied by increased levels of p-ERK protein.

CONCLUSIONS

Treatment with ozone prevents intestinal mucosal damage, stimulates cell proliferation and inhibits programmed cell death following intestinal IR in a rat.

Treatment with chlorhexidine modifies the healing of colon anastomosis in rats

PURPOSE

To investigate the effects of chlorhexidine on the healing of colon anastomosis in the presence of peritonitis.

METHODS

Peritonitis was induced in male Wistar rats by cecal ligation and puncture (CLP). The abdominal cavities of experimental animals were irrigated with warm solutions containing 0.9% saline (SAL group; n = 8) or 0.05% chlorhexidine (CHD group; n = 8), following which colon anastomosis was performed. Rats of the control group (n = 8) were submitted to colon anastomosis but not to CLP. Animals were euthanized seven days after surgery, and healing was assessed by histopathological examination and by measuring anastomotic burst pressure.

RESULTS

Post-operative survival rates were 100, 87.5 and 75% for the control, SAL, and CHD groups, respectively. The degree of inflammation was significantly lower (ρ = 0.01) in the CHD group compared with the other groups, whilst the anastomotic burst pressure within the CHD group (156.7 ± 53.2 mmHg) was lower than, but not significantly different from, those of the control and SAL groups (196.3 ± 49.8, 208.6 ± 72.7 mmHg, respectively).

CONCLUSIONS

Peritoneal irrigation with chlorhexidine solution is effective in the control of inflammation promoted by peritonitis but does not improve healing of colon anastomosis in rats.

Protective effects of medical ozone combined with traditional Chinese medicine against chemically-induced hepatic injury in dogs

AIM

To investigate the protective effect of medical ozone (O(3)) combined with Traditional Chinese Medicine (TCM) Yigan Fuzheng Paidu Capsules (YC) against carbon tetrachloride (CCl(4))-induced hepatic injury in dogs.

METHODS

Thirty healthy dogs were divided randomly into five groups (n = 6 in each group), namely control, oleanolic acid tablet (OAT), O(3), YC and O(3) + YC, given either no particular pre-treatment, oral OAT, medical ozone rectal insulfflation every other day, oral YC, or oral YC plus medical ozone rectal insulfflation every other day, respectively, for 30 consecutive days. After pre-treatment, acute hepatic injury was induced in all dogs with a single-dose intraperitoneal injection of CCl(4). General condition and survival time were recorded. The biochemical and hematological indexes of alanine aminotransferase (ALT), aspartate aminotransferase/alanine aminotransferase (AST/ALT), serum total bilirubin (TBIL), prothrombin time (PT), blood ammonia (AMMO), and blood urea nitrogen (BUN) were measured after CCl(4) injection. Hepatic pathological changes were also observed.

RESULTS

Compared to the other four groups, the changes of group O(3) + YC dogs' general conditions (motoricity, mental state, eating, urination and defecation) could be better controlled. In group O(3) + YC the survival rates were higher (P < 0.05 vs group control). AST/ALT values were kept within a normal level in group O(3) + YC. Hepatic histopathology showed that hepatic injury in group O(3) + YC was less serious than those in the other four groups.

CONCLUSION

Medical ozone combined with TCM YC could exert a protective effect on acute liver injury induced by CCl(4).