Diagnosis and management of splanchnic ischemia

Figure 1 Classification of splanchnic, or gastrointestinal ischemia. ASS: Acute splanchnic syndrome; CSS: Chronic splanchnic syndrome; CACS, Celiac artery compression syndrome; NOMI: Non-occlusive mesenteric ischemia.

Figure 2 Collateral vessels: gastroduodenal (GD) artery and Buehlers artery (B). A: The gastroduodenal (GD) artery and Buehlers artery (B) are visible on non-selective aortography indicating stenosis of the origin of either the CA or SMA. The late filling of the CA points to a stenosis in its origin; B: Lateral aortography showing an asymmetrical stenosis of the CA; C: On selective cannulation of the SMA, both collaterals are more clearly visible.

Figure 3 Tonometer balloon placed in the stomach nasogastrically. CO₂ diffuses rapidly over different membranes, therefore the tonometer PCO₂ (PtCO₂) will be in equilibrium with gastric luminal PCO₂ (PgCO₂) and mucosal PCO₂ (PmCO₂). The PCO₂ can be measured from the catheter either from injected saline using blood gas analyzers or by connection to a semi-automated Tonocap device. The underlying physiological principle is that ischemia is always associated with PCO₂ increase. Therefore, focal measurement of ischemia is possible for long periods via a minimally invasive technique.

Figure 4 Imminent ASS and normal gastric and jejunal PCO₂ pattern. A: Normal 24 h PCO₂ pattern in the stomach (squares) and jejunum (diamonds) with variation in PCO₂, but no peaks above 11 kPa following meals; B: Imminent bowel infarction in a patient with severe 3 vessel CSS. After her evening meal she had pain for almost 6 h, and extreme ischemia with PCO₂ > 16 kPa for 7 h. She was treated with endovascular stent placement the day after this measurement, with immediate relief of complaints. She is still doing well, over 3 years later.