Effects of CO(2) pneumoperitoneum on anastomotic healing in rats receiving preoperative 5-fluorouracil neoadjuvant chemotherapy

The effect of taurine on flap perfusion and viability in random pattern flaps in rats

BACKGROUND

In present study, the effect of taurine on flap perfusion and viability was examined using the modified random pattern dorsal flap model (DFM).

MATERIALS AND METHODS

Eighteen rats were included and divided equally (n=9) to taurine treatment and control groups in this study. Taurine treatments were given orally at a dose of 100 mg/kg/day. Taurine group received taurine, starting 3 days before the operation till the postoperative 3^rd day. Angiographic images were recorded when the flaps were sutured back and on postoperative 5^th and 7^th days. Necrosis calculations were made with all the images obtained by the digital camera and the indocyanine green angiography. Fluorescence intensity, fluorescence filling rate and flow rate of DFM were calculated by the SPY device and the SPY-Q software. All flaps were analyzed histopathologically, also.

RESULTS

Perioperative taurine treatment significantly reduced necrosis rates and increased the fluorescence density, the fluorescence filling rate and the flap filling rates in the DFM (p<0.05). Reduced amounts of necrosis, ulcer and polymorphonuclear leukocyte supported the beneficial effect of taurine histopathologically (p<0.05).

CONCLUSIONS

Taurine may be used as an effective medical agent for prophylactic treatment options in flap surgery.

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.