Risk Of Mesenteric Ischemia Research Articles

Selepressin, a novel selective V1A receptor agonist: Effect on mesenteric flow and gastric mucosa perfusion in the endotoxemic rabbit

Intestinal or mesenteric ischemia generally leads to inflammation and injury, potentially developing hypoxia, causing cell death and tissue necrosis. This in turn can lead to sepsis and shock. Conversely, following shock, the intestinal tract is a main organ to experience ischemic/reperfusion injury. Increased intestinal cell-membrane permeability through mesenteric ischemia provoking bacterial translocation and gut-barrier injury can lead to sepsis and multi-organ failure. Hypotension induced by systemic vasodilation and vascular leak in systemic inflammatory response syndrome and sepsis is countered by immediate fluid resuscitation and vasopressor administration, primarily norepinephrine (NE), with possible arginine vasopressin (AVP) supplementation, an agonist of vasopressin V1A and V2 receptors. Selepressin is a selective V1A-receptor agonist, avoiding potential V2 receptor-associated adverse effects. Selepressin, non-selective AVP, and NE effects on mesenteric blood flow (MBF) and gastric mucosa perfusion (GMP) were compared in control rabbits and a lipopolysaccharide-induced, fluid-resuscitated rabbit endotoxemia model. AVP induced a pronounced decrease in MBF and GMP in non-endotoxemic and endotoxemic rabbits, whereas the reduction after selepressin treatment was significantly less for both indicators in the endotoxemic animals. By contrast, NE increased the MBF and did not affect GMP in both groups. Selepressin and AVP induced a pronounced dose-dependent increase in mesenteric vascular resistance in non-endotoxemic and endotoxemic rabbits, tending to be less in endotoxemic animals, whereas a minor increase in both groups was observed with NE. Therefore, in this safety study, the risk for mesenteric ischemia on selepressin treatment was not inferior to AVP, being less in endotoxemic than in non-endotoxemic animals.

Different Risk of Common Gastrointestinal Disease Between Groups Undergoing Hemodialysis or Peritoneal Dialysis or With Non-End Stage Renal Disease: A Nationwide Population-Based Cohort Study.

Peritoneal dialysis (PD) is one type of renal replacement therapy, but potential peritoneal damage and gastrointestinal (GI) tract adverse effects during long-term exposure to bio-incompatible dialysate remain a concern. Although GI disease frequently occurs in dialysis patients, whether the risk of GI diseases differs among PD and hemodialysis (HD) or non-uremic groups is still uncertain.In this retrospective cohort study, data were obtained from the National Health Insurance Research Database, which includes almost all dialysis patients in Taiwan. Between 2000 and 2009, a total of 1791 PD and 8955 HD incident patients were enrolled and matched for age and sex or for propensity score. In addition, a comparison cohort of 8955 non-uremic patients was also selected. Individuals were monitored for the occurrence of common GI diseases until 2010, and data were analyzed using several different models.Generally speaking, the results showed that the risk of gastroesophageal reflux, intestinal obstruction or adhesions, and abdominal hernia was significantly higher in the PD group, whereas the risk of peptic ulcer disease and lower GI diverticula and bleeding was significantly greater in the HD group. Meanwhile, the risk of mesenteric ischemia, liver cirrhosis, and acute pancreatitis was higher in dialysis patients, but was not significantly different between the PD and HD groups; moreover, the risk of appendicitis in the PD group appeared to be lower than that in the HD group.In conclusion, dialysis patients have a higher risk of most common GI diseases, and PD and HD modalities are associated with different GI diseases.

Bronchoscopy is associated with decreased mesenteric arterial flow*

We hypothesized that fiberoptic bronchoscopy can contribute to mesenteric ischemia and bacterial translocation. To test this hypothesis we investigated in patients undergoing bronchoscopy mesenteric blood flow and markers in association with ischemia reperfusion injury. Forty-seven consecutive patients requiring diagnostic fiberoptic bronchoscopy were studied. Parameters evaluated were superior mesenteric artery Doppler sonography, oxidative stress mediators, arterial blood gases, blood cultures pre-fiberoptic bronchoscopy, and 1st, 4th, and 24th hr post-fiberoptic bronchoscopy. After bronchoscopy; PaO2 decreased by 21.8% +/- 1.5% (range 6-40), and remained low at all time points (p = 0.0001, p = 0.0001, p = 0.008). Flow volume decreased by 38.8% +/- 14.9% (range 6-72), and remained low at 1st and 4th hr (p = 0.0001, p = 0.01). Resistive and pulsatile index increased at 1st hr (p = 0.0001, p = 0.001) and 4th hr (p = 0.018, p = 0.045). Myeloperoxidase and malondialdehyde increased at 1st hr (p = 0.0001) and 4th hr (p = 0.037, p = 0.028). Corresponding glutathione and catalase decreased at 1st hr (p = 0.0001), and glutathione remained significant at 4th and 24th hr (p = 0.0001, p = 0.003). Correlation between flow volume and PaO2 (r = .71, p = 0.0001), myeloperoxidase (r = -.39, p = 0.05), glutathione (r = .41, p = 0.03) was significant. Nine of 47 (19.1%) had fever, and 3 of 47 (6.4%) had gram-negative bacteremia. Fiberoptic bronchoscopy is associated with decreased mesenteric blood flow, which may place the patient at risk for mesenteric ischemia and gastrointestinal bacterial translocation.

Repair of an Abdominal Aortic Aneurysm with a Remarkably Dilated Meandering Artery: Report of a Case

A 73-year-old man on dialysis for chronic renal dysfunction was referred to our hospital for surgical treatment of an abdominal aortic aneurysm (AAA). Preoperative angiography showed a remarkably developed meandering artery branching from the inferior mesenteric artery (IMA). The superior mesenteric and celiac arteries were occluded at the origin, and all blood flow to the abdominal organs was apparently supplied by collateral circulation from the IMA. Considering the risk of mesenteric ischemia after aortic clamping in conjunction during surgery, we used a perfusion catheter with a 12-F balloon to create a shunt to the IMA from the subclavian artery. The operation was successful and the patient recovered uneventfully. We describe this surgical procedure for its effectiveness in preventing postoperative mesenteric ischemia in a rare case of an AAA with complex branching lesions.

Mesenteric blood flow velocities in the newborn with single-ventricle physiology: Modified Blalock-Taussig shunt versus right ventricle-pulmonary artery conduit

Neonates with ductal-dependent single-ventricle congenital heart disease palliated with a modified Blalock-Taussig shunt (mBTS) commonly have retrograde diastolic flow in the aorta, which may place them at increased risk of mesenteric ischemia. Recently, palliation with a right ventricle-to-pulmonary artery conduit, known as the Sano procedure, has been shown to eliminate retrograde diastolic flow, theoretically leading to better systemic perfusion. To compare the changes in superior mesenteric artery (SMA) and celiac artery velocities and flow after a bolus enteral feed in patients with single-ventricle congenital heart disease palliated with an mBTS vs. those palliated with the right ventricle-to-pulmonary artery conduit. Prospective clinical study. Cardiothoracic intensive care unit and pediatric ward of a tertiary care children's hospital. A total of 27 patients with single-ventricle congenital heart disease (15 with mBTS, 12 with Sano) after stage-1 palliation. Doppler ultrasound of the SMA and celiac artery was performed 30 mins before and after a bolus enteral feed. SMA and celiac artery peak systolic flow velocity, mean flow velocity, and time-velocity integral were measured. After a bolus enteral feed, 8 of 15 infants palliated with an mBTS had retrograde diastolic flow through the SMA yet demonstrated significant increases in all variables of both the SMA and celiac artery flow velocities (SMA peak systolic flow velocity: 0.96 +/- 0.33 vs. 1.2 +/- 0.4 m/sec, p = .01). Those palliated with the Sano procedure did not demonstrate SMA retrograde diastolic flow but also did not have any significant changes in their mesenteric flow variables (SMA peak systolic flow velocity: 0.79 +/- 0.16 vs. 0.89 +/- 0.26 m/sec, p = .2). Postprandial retrograde diastolic flow was observed in the majority of patients palliated with an mBTS vs. none of the patients in the Sano group. However, contrary to expectations, postprandial mesenteric blood flow velocities in those palliated with an mBTS are significantly higher than in Sano patients, although the increase is not as high as that historically seen in normal neonates. This may place this population at risk for mesenteric ischemia and feeding intolerance in the postoperative period, and the risk may be even greater for those neonates palliated with a right ventricle-to-pulmonary artery conduit.