Effects of hyperbaric oxygen and Pgg-glucan on ischemic colon anastomosis

Hyperbaric oxygen treatment for late low colorectal anastomosis ischaemia: Case report

INTRODUCTION

This report describes the use of hyperbaric oxygen treatment (HBOT) to treat a case of colorectal anastomosis ischaemia following colorectal surgery.

CASE REPORT

A 47-year-old man developed post-operative colorectal anastomosis ischaemia with leak after laparoscopic low anterior resection for T3N0 adenocarcinoma of the rectum. The leak with concomitant ischaemia presented 17 days after surgery. HBOT was administrated in 11 sessions over three weeks and the patient followed endoscopically and radiologically for two months. At two months the anastomosis showed both endoscopic and radiological healing; therefore the ileostomy was closed. Anal function was satisfactory with no incontinence or evidence of sepsis.

CONCLUSIONS

Intra-operative or late leak with concomitant ischaemia of a colorectal anastomosis is a challenging event in colorectal surgery. HBOT may be beneficial in promoting healing in selected patients. Further studies are needed to evaluate conservative treatments and the role of HBOT.

Effect of preconditioning and postoperative hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats

Purpose

To investigate the effect of hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats.

Methods

Forty female rats underwent segmental resection of 1 cm of the left colon followed by end-to-end anastomosis. They were randomly assigned to four groups (n=10 each), a sham group; two groups were submitted to Hyperbaric Oxygen therapy (HBOT) with and without induced ischemia and the induced ischemia group without HBOT. The HBOT protocol evaluated was 100% O2 at 2.4 Atmosphere absolute pressure (ATA) for 60 minutes, two sessions before as a preconditioning protocol and three sessions after the operation. Clinical course and mortality were monitored during all experiment and on the day of euthanasia on the fourth day after laparotomy. Macroscopic appearance of the abdominal cavity were assessed and samples for breaking strength of the anastomosis and histopathological parameters were collected.

Results

There was no statistically significant difference in mortality or anastomosis leak between the four experimental groups. Anastomosis breaking strength was similar across groups.

Conclusion

The HBOT protocol tested herein at 2.4 ATA did not affect histopathological and biomechanical parameters of colonic anastomotic healing, neither the clinical outcomes death and anastomosis leak on the fourth day after laparotomy.

Systematic Review on the Influence of Tissue Oxygenation on Gut Microbiota and Anastomotic Healing

BACKGROUND

Anastomotic leak rates have not improved over several decades despite improvements in surgical techniques and patient care. The gut microbiome has been implicated in the development of leaks. The exact mechanisms by which tissue oxygenation affects gut microbial composition and anastomotic healing physiology are unclear. Also, commonly used carbon dioxide (CO₂) is a known vasodilator that improves tissue oxygen tension. We performed a systematic review to determine the influence of hyperoxia, hypoxia, and hypercapnia on the gut microbiome and anastomotic healing.

METHODS

A literature search was performed in MEDLINE, EMBASE, and COCHRANE to identify studies investigating the effects of hyperoxia, hypoxia, and hypercapnia on anastomotic healing and gut microbiota published between 1998 and 2018. Two reviewers screened the articles for eligibility and quality. Fifty-three articles underwent full text review, and a narrative synthesis was undertaken.

RESULTS

Hyperoxia is associated with better anastomotic healing, increased gastrointestinal oxygen tension, and may reduce gut anaerobes. Hypoxia is associated with poor healing and increased gut anaerobes. However, it is unclear if hypoxia is the most important predictor of anastomotic leaks. Low pressure CO₂ pneumoperitoneum and mild systemic hypercapnia are both associated with increased gastrointestinal oxygen tension and may improve anastomotic healing. We found no studies which investigated the effect of hypercapnia on gut microbiota in the context of anastomotic healing.

CONCLUSIONS

Tissue oxygenation influences gut anastomotic healing, but little evidence exists to demonstrate the influence on the gut microbiome in the context of healing. Further studies are needed to determine if anastomotic microbiome changes with altered tissue oxygenation and if this affects healing and leak rates. If confirmed, altering tissue oxygenation through hyperoxia or hypercapnia could be feasible means of altering the microbiome such that anastomotic leak rates reduce.

Meta-analysis on the effect of hyperbaric oxygen as adjunctive therapy in the outcome of anastomotic healing of experimental colorectal resections in rats

BACKGROUND

Colorectal cancer is the third most common form of cancer and colorectal surgery is the treatment of choice in local disease. Anastomotic leakage following colorectal surgery is a major complication with a high incidence and mortality. Adjuvant hyperbaric oxygen treatment (HBOT) may be associated with reduction of anastomotic leakage. A systematic review was conducted regarding HBOT as an adjunctive therapy to colorectal surgery.

METHODS

Systematic review (1900-2017) using PubMed, Cochrane, EMBASE, Web of Science and EMCARE. All original published studies on the effect of HBOT as an adjunctive therapy for colorectal surgery with the creation of an anastomosis were considered.

RESULTS

Thirteen small animal trials were included for qualitative synthesis. We found no human trials. Eleven trials used bursting pressure whilst eight used hydroxyproline levels as a marker for collagen synthesis as primary outcome to assess the strength of the anastomosis. A meta-analysis performed for normal and ischaemic anastomoses showed that postoperative HBOT improves bursting pressure and hydroxyproline levels significantly in both normal (p ≤ 0.001 and p = 0.02) and ischaemic anastomoses (p ≤ 0.001 and p = 0.04).

CONCLUSION

Postoperative HBOT has a positive effect on colorectal anastomoses in rats. Further research should focus on a larger systematic animal study.

The Effects of Simvastatin on Ischemia Reperfusion Injury in an Experimental Colon Anastomosis Model

Anastomotic leakage is more frequently reported in colonic anastomoses. Ischemia reperfusion injury is one of the main reasons for anastomotic leakage. Simvastatin is known to prevent tissue damage induced by free oxygen radicals after ischemia reperfusion injury. The effect of simvastatin on colonic anastomosis impaired by ischemia reperfusion injury is investigated. Single layer, end-to-end colocolic anastomosis after 0.5-cm colon resection was performed in Wistar Albino rats. In Group 1 (control) (n = 10), colonic anastomosis without I-R was performed. In Group 2 (n = 10), the superior mesenteric artery was clamped for 10 min followed by 60 min of reperfusion after which resection anastomosis was performed. In Group 3 (n = 10), 10 mg/kg simvastatin was given by gavage for 7 days after I-R and resection anastomosis. In Group 4 (n = 10), the rats received 10 mg/kg simvastatin by gavage 7 days before and 7 days after ischemia reperfusion and surgery. All of the rats were sacrificed 8 days after surgery. Anastomotic bursting pressure and tissue hydroxyproline levels were measured. Postoperative administration of simvastatin restored the anastomotic bursting pressure and hydroxyproline levels to that of control group thus overcoming the effect of ischemia reperfusion injury. Simvastatin administered postoperatively in an experimental model of colonic resection anastomosis impaired by ischemia reperfusion injury increased anastomotic bursting pressures and tissue hydroxyproline levels. Further experimental and clinical studies will show whether administration of simvastatin will increase reliability of the anastomosis and decrease postoperative morbidity and mortality in colonic anastomosis after ischemia reperfusion injury.

Equivocal effect of intraoperative fluorescence angiography on colorectal anastomotic leaks

BACKGROUND

Intraoperative fluorescence angiography is beneficial in several surgical settings to assess tissue perfusion. It is also used to assess bowel perfusion, but its role in improving outcomes in colorectal surgery has not been studied.

OBJECTIVE

The purpose of this work was to determine whether intraoperative angiography decreases colorectal anastomotic leaks.

DESIGN

This was a case-matched retrospective study in which patients were matched 1:1 with respect to sex, age, level of anastomosis, presence of a diverting loop ileostomy, and preoperative pelvic radiation therapy.

SETTINGS

The study was conducted at an academic medical center.

PATIENTS

Patients who underwent colectomy or proctectomy with primary anastomoses were included.

INTERVENTIONS

The intraoperative use of fluorescence angiography to assess perfusion of the colon for anastomosis was studied.

MAIN OUTCOME MEASURES

Anastomotic leak within 60 days and whether angiography changed surgical management were the main outcomes measured.

RESULTS

Case matching produced 173 pairs. The groups were also comparable with respect to BMI, smoking status, diabetes mellitus, surgical indications, and type of resection. In patients who had intraoperative angiography, 7.5% developed anastomotic leak, whereas 6.4% of those without angiography did (p value not significant). Univariate analysis revealed that preoperative pelvic radiation, more distal anastomosis, surgeon, and diverting loop ileostomy were positively associated with anastomotic leak. Multivariate analysis demonstrated that level of anastomosis and surgeon were associated with leaks. Poor perfusion of the proximal colon seen on angiography led to additional colon resection before anastomosis in 5% of patients who underwent intraoperative angiography.

LIMITATIONS

The retrospective study design with the use of historical control subjects, selection bias, and small sample size were limitations to this study.

CONCLUSIONS

Intraoperative fluorescence angiography to assess the perfusion of the colon conduit for anastomosis was not associated with colorectal anastomotic leak. Perfusion is but one of multiple factors contributing to anastomotic leaks. Additional studies are necessary to determine whether this technology is beneficial for colorectal surgery.

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.

Hyperbaric oxygen therapy and mechanical resistence of the colonics anastomosis in rats with peritonitis

PURPOSE

To analyze the effects of hyperbaric oxygen therapy (HBO) on the mechanical resistance of anastomosis performed in rats' distal colon presenting peritonitis induced by ligature and cecal punction using the Total Energy Rupture biomechanical test (ETR).

METHODS

It was used 45 rats divided into three groups of 15 animals each. In Control Group (CG), it was performed anastomosis in distal colon without peritonitis. In Peritonitis Group (PG), it was performed anastomosis six hours after the induction of peritonitis by ligature and cecal punction. In Hyperbaric Chamber Group (HCG), it was performed six hours after the induction of peritonitis by ligature and cecal punction. The animals on CG and PG were kept at place air while the animals on HCG were placed on an experimental hyperbaric chamber in order to inhale oxygen at 100%, two absolute atmospheres, for 120 minutes, for four consecutive days. Euthanasia took place on the fifth day of the experiment. All the animals underwent to Total Energy Rupture Biomechanical Resistance test (ETR). Total Energy Rupture was defined as the necessary internal energy stored up to promote the colon rupture after an external traction force imposition.

RESULTS

The Peritonitis Group presents smaller average ETR than Control Group. There was no statistical difference between Peritonitis Group and Hyberbaric Chamber Group.

CONCLUSION

Hyperbaric oxygen therapy did not alter the mechanical resistance of anastomosis performed in distal colon of rats under the presence of peritonitis induced by ligature and cecal puncture.

The effects of hyperbaric oxygen therapy on colonic anastomosis in rats with peritonitis

The aim of this study is to investigate the healing effect of hyperbaric oxygen (HBO) on colonic anastomoses in the presence of experimentally induced peritonitis. Thirty-two rats were allocated randomly into short-term anastomosis (STA), short-term anastomosis + HBO treatment (STA+HBO), long-term anastomosis (LTA), and long-term anastomosis + HBO (LTA+HBO) treatment groups. The STA and LTA groups were administered fluid resuscitation and antibiotics for 3 and 7 days, respectively, whereas the HBO treatment groups received additional HBO therapy for 3 and 7 days, respectively. The rats were reoperated on the third and the seventh days of anostomoses for evaluation. The bursting pressures in STA+HBO and LTA+HBO therapy groups were significantly higher than those in groups with anastomoses alone (p < .001 and p < .01). HBO therapy did not affect the fibrotic index neither in STA nor in LTA groups (p > .05 for both); however, it was significantly higher in LTA+HBO group than that in STA+HBO group (p < .05). The hydroxyproline level was significantly higher in LTA group than in STA group (p < .05), yet HBO therapy did not affect the hydroxyproline levels in STA or LTA groups (p > .05 for both). It is concluded that hyperbaric oxygen treatment has positive effects on colonic anastomotic healing in case of peritonitis.