Changes in small intestinal oxygenation during hemodialysis: A case report

Gastrointestinal symptoms are common in patients undergoing hemodialysis (HD) and closely associated with mesenteric ischemia, a life-threatening condition with high mortality.Non-occlusive mesenteric ischemia can be triggered by HD; however, its early diagnosis remains challenging.Near-infrared spectroscopy enables real-time assessment of regional tissue oxygen saturation (rSO); however, monitoring intestinal rSO in adults has not been reported, likely due to limited light penetration through the abdominal wall.Here we report a case in which intestinal rSO was successfully measured through a hernial orifice during HD.A 94-year-old man receiving maintenance HD for nephrosclerosis-related chronic kidney disease underwent continuous rSO monitoring at three sites-forehead (brain), right hypochondrium (liver), and abdominal incisional hernia orifice (small intestine)-using an INVOS 5100c oximeter (Covidien Japan).HD was performed under hemodynamically stable conditions without intradialytic hypotension.During HD, cerebral and hepatic rSO remained stable, whereas intestinal rSO began to decline shortly after its initiation and showed a rapid and marked decrease following an increase in the ultrafiltration rate from 430 to 530 mL/h.A partial recovery was observed thereafter; however, intestinal rSO remained approximately 20% below baseline at the end of the HD.Continuous monitoring of intestinal rSO during HD revealed that intestinal perfusion can decrease even when systemic hemodynamics remains stable.