Intraoperative Patterns of Gastric Microperfusion During Laparoscopic Roux-en-Y Gastric Bypass

Introduction

Visible light spectroscopy (VLS) represents a sensitive, non-invasive method to quantify tissue oxygen levels and detect hypoxemia. The aim of this study was to assess the microperfusion patterns of the gastric pouch during laparoscopic Roux-en-Y gastric bypass (LRYGB) using the VLS technique.

Methods

Twenty patients were enrolled. Tissue oxygenation (StO2%) measurements were performed at three different localizations of the gastric wall, prior and after the creation of the gastric pouch, and after the creation of the gastro-jejunostomy.

Results

Prior to the creation of the gastric pouch, the lowest StO2% levels were observed at the level of the distal esophagus with a median StO2% of 43 (IQR 40.8–49.5). After the creation of the gastric pouch and after the creation of the gastro-jejunostomy, the lowest StO2% levels were recorded at the level of the His angle with median values of 29% (IQR 20–38.5) and 34.5% (IQR 19–39), respectively. The highest mean StO2 reduction was recorded at the level of the His angle after the creation of the gastric pouch, and it was 18.3% (SD ± 18.1%, p < 0.001). A reduction of StO2% was recorded at all localizations after the formation of the gastro-jejunostomy compared to the beginning of the operation, but the mean differences of the StO2% levels were statistically significant only at the resection line of the pouch and at the His angle (p = 0.044 and p < 0.001, respectively).

Conclusion

Gastric pouch demonstrates reduction of StO2% during LRYGB. VLS is a useful technique to assess microperfusion patterns of the stomach during LRYGB.

Graphical abstract

     

Development of an auxotrophic oral live Shigella flexneri vaccine

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Effects of low and high dose oral contraceptives on blood coagulation and thrombogenesis induced by vascular subendothelium exposed to flowing human blood.

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华蟾蜍毒素对离体豚鼠输精管的作用

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Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results

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Cysticercosis of the brain. The value of computed tomography

Incidence and radiologic findings of neurocysticercosis were investigated in a series of 23,800 consecutive head examinations using computed tomography (CT). The condition was diagnosed in 168 cases (0.7%). The parenchymatous form was the most common presentation (96.3%), while the meningeal form corresponded to only 11.9 per cent of cases. These two forms coexisted in some cases. These findings reversed the knowledge on the condition based on conventional radiography. The different CT appearances in the brain are described and a new radiologic protocol for the CT evaluation of the condition is advocated, which includes a follow-up after a trial cure with Praziquantel in the presence of cysts not associated with suggestive brain calcifications. CT was more sensitive than conventional radiography in the differentiation between dead and living larvae, thus having an impact on the therapeutic management of the patients.