Role of Beta Blockers in EHPVO in Children
Non-selective beta blockers (NSBBs) are effective in reducing gastrointestinal bleeding episodes in children with extrahepatic portal vein obstruction (EHPVO), though evidence is limited and their use should be considered as part of a comprehensive management approach rather than as standalone therapy.
Pathophysiology and Hemodynamic Effects
- Hemodynamic data from both animal models with pre-hepatic portal hypertension and patients with non-cirrhotic portal hypertension demonstrate beneficial effects of non-selective beta adrenergic blockade on splanchnic hemodynamics 1
- NSBBs cause vasoconstriction of the splanchnic circulation through β2-receptor inhibition and decrease cardiac output via β1-receptor blockade, leading to decreased portal venous inflow and lower portal pressure 1
- The theoretical concerns about deleterious effects of NSBBs on patients with extended thrombosis (potentially promoting abdominal pain or intestinal ischemia) have never been proven in clinical practice 1
Evidence for Beta Blockers in EHPVO
- According to multivariate analysis, beta adrenergic blockade decreases the risk of bleeding in patients with large varices and improves survival in patients with chronic portomesenteric venous obstruction 1
- A study in Egyptian children with EHPVO demonstrated that propranolol was associated with significant reduction in bleeding episodes (p<0.001), though it was also associated with increased chest symptoms (p<0.01) 2
- In a study from Ghana, children with EHPVO and massive upper gastrointestinal bleeding were successfully managed with a protocol that included propranolol for long-term secondary prophylaxis 3
Management Approach for Children with EHPVO
Primary Prophylaxis
- There is insufficient evidence to recommend beta blockers for primary prophylaxis of variceal bleeding in children with EHPVO 4
- The Cystic Fibrosis Foundation (CFF) cannot recommend for or against the use of NSBBs for primary prophylaxis of variceal bleeding in children due to insufficient evidence 1
Secondary Prophylaxis
- For children who have already experienced variceal bleeding:
- Endoscopic therapy (sclerotherapy or band ligation) is effective for secondary prophylaxis 4
- Propranolol has shown efficacy in reducing rebleeding episodes 2, 3
- A stepwise approach including NSBBs, endoscopic variceal obliteration (EVO), and surgical options when necessary has demonstrated excellent survival and bleeding control 5
Endoscopic vs. Pharmacological Therapy
- Endoscopic variceal band ligation is superior to sclerotherapy according to short-term randomized controlled trials in children 1
- In children, a combination of ligation and sclerotherapy may provide marginal advantage over either technique alone 1
- When comparing propranolol to band ligation in adults with non-cirrhotic portal hypertension (including EHPVO), no difference in rebleeding rates was observed at two years follow-up 1
Special Considerations and Limitations
- The desired reduction of 20% in portal pressure gradient is achieved in about 50-75% of patients with propranolol or carvedilol, respectively 1
- Beta blockers may have potential adverse effects on pulmonary function, though no studies specifically assessing worsening of lung disease in children with EHPVO have been conducted 1
- Hypotension (systolic blood pressure below 90 mmHg) is a contraindication to beta blocker use 1
- In cases where medical and endoscopic management fails, surgical options should be considered:
Conclusion
Beta blockers play an important role in the management of EHPVO in children, particularly for secondary prophylaxis of variceal bleeding. However, they should be used as part of a comprehensive approach that may include endoscopic therapy and, when necessary, surgical interventions. The choice of therapy should be based on the child's specific clinical situation, local expertise, and available resources.