Octreotide for recurrent intestinal variceal bleeding in patients without portal hypertension

An obscure cause of gastrointestinal bleeding: Recurrent duodenal variceal hemorrhage treated with intramuscular octreotide in the absence of portal hypertension

Duodenal varices (DVs) are ectopic gastrointestinal varices (ECVs) associated with portal hypertension (PH). We present the case of an 82-year-old woman who presented with symptomatic anemia secondary to DV hemorrhage diagnosed on oesophagogastroduodenoscopy. This lesion was treated with endoscopic adrenaline injection and clip application. The patient re-presented on multiple occasions with bleeding recurrence localized to the duodenum, which was managed with intramuscular octreotide and oral beta-blockade resulting in sustained remission of bleeding. This case highlights a rare cause of upper gastrointestinal hemorrhage and highlights the value of somatostatin analogues for conservative treatment of DVs.

Role of octreotide in small bowel bleeding

Gastrointestinal bleeding accounts for a drastic negative impact on the quality of the patients' lives as it requires multiple diagnostic and therapeutic interventions to identify the source of the bleeding. Small bowel bleeding is the least common cause of gastrointestinal bleeding. However, it is responsible for the majority of complaints from patients with persisting or recurring bleeding where the primary source of bleeding cannot be identified despite investigation. A somatostatin analog known as octreotide is among the medical treatment modalities currently used to manage small bowel bleeding. This medication helps control symptoms of gastrointestinal bleeding by augmenting platelet aggregation, decreasing splanchnic blood flow, and antagonizing angiogenesis. In this review article, we will highlight the clinical efficacy of octreotide in small bowel bleeding and its subsequent effect on morbidity and mortality.

Murine study of portal hypertension associated endothelin-1 hypo-response

AIM: To investigate endothelin-1 hypo-responsive associated with portal hypertension in order to improve patient treatment outcomes.

METHODS: Wild type, eNOS^-/- and iNOS^-/- mice received partial portal vein ligation surgery to induce portal hypertension or sham surgery. Development of portal hypertension was determined by measuring the splenic pulp pressure, abdominal aortic flow and portal systemic shunting. To measure splenic pulp pressure, a microtip pressure transducer was inserted into the spleen pulp. Abdominal aortic flow was measured by placing an ultrasonic Doppler flow probe around the abdominal aorta between the diaphragm and celiac artery. Portal systemic shunting was calculated by injection of fluorescent microspheres in to the splenic vein and determining the percentage accumulation of spheres in liver and pulmonary beds. Endothelin-1 hypo-response was evaluated by measuring the change in abdominal aortic flow in response to endothelin-1 intravenous administration. In addition, thoracic aorta endothelin-1 contraction was measured in 5 mm isolated thoracic aorta rings ex-vivo using an ADI small vessel myograph.

RESULTS: In wild type and iNOS^-/- mice splenic pulp pressure increased from 7.5 ± 1.1 mmHg and 7.2 ± 1 mmHg to 25.4 ± 3.1 mmHg and 22 ± 4 mmHg respectively. In eNOS^-/- mice splenic pulp pressure was increased after 1 d (P = NS), after which it decreased and by 7 d was not significantly elevated when compared to 7 d sham operated controls (6.9 ± 0.6 mmHg and 7.3 ± 0.8 mmHg respectively, P = 0.3). Abdominal aortic flow was increased by 80% and 73% in 7 d portal vein ligated wild type and iNOS when compared to shams, whereas there was no significant difference in 7 d portal vein ligated eNOS^-/- mice when compared to shams. Endothelin-1 induced a rapid reduction in abdominal aortic blood flow in wild type, eNOS^-/- and iNOS^-/- sham mice (50% ± 8%, 73% ± 9% and 47% ± 9% respectively). Following portal vein ligation endothelin-1 reduction in blood flow was significantly diminished in each mouse group. Abdominal aortic flow was reduced by 19% ± 9%, 32% ± 10% and 9% ± 9% in wild type, eNOS^-/- and iNOS^-/- mice respectively.

CONCLUSION: Aberrant endothelin-1 response in murine portal hypertension is NOS isoform independent. Moreover, portal hypertension in the portal vein ligation model is independent of ET-1 function.