Mucosal and serosal changes after gastric stapling determined by a new "real-time" surface tissue oxygenation probe:...

Area of Science:

• Surgical Innovation
• Biomedical Engineering
• Gastrointestinal Surgery

Background:

• Surgeons currently use subjective methods to assess tissue ischemia at surgical anastomoses.
• These methods may fail to detect transient or minor ischemia, potentially leading to complications like leakage and stricture.
• A novel microvascular tissue oximeter probe offers noninvasive, real-time measurement of tissue hemoglobin oxygen saturation (StO(2)).

Purpose of the Study:

• To evaluate the reproducibility of the T-Stat oximeter probe for measuring gastric StO(2).
• To compare the sensitivity of gastric mucosa versus serosa to ischemia.
• To determine the impact of proximity to the staple line on StO(2) measurements.

Main Methods:

• Anesthetized swine (n=8) underwent gastric transection using 4.8-mm staple height cartridges.
• Local gastric StO(2) was measured in vivo at two locations: adjacent to the staple line and 2 cm away.
• Measurements were taken to assess reproducibility, mucosal vs. serosal sensitivity, and proximity effects.

Main Results:

• Both mucosal and serosal StO(2) significantly decreased adjacent to the staple line compared to baseline (P <.05).
• No significant StO(2) changes were observed 2 cm away from the staple line.
• Visible changes in tissue color or pulsation were not detected despite significant StO(2) drops.

Conclusions:

• Significant, reproducible decreases in mucosal and serosal StO(2) were detected near gastric staple lines.
• The dramatic drop in mucosal StO(2) occurred without any visible signs of ischemia.
• Real-time oximetry could help identify patients at risk for anastomotic complications.