Background: The oral vasopressin-2 receptor antagonist tolvaptan causes aquaresis, and its effect on heart failure is proven. However, it is not recommended in patients who are unable to appropriately respond to thirst because of possible severe hypernatremia. Aim: To assess the safety and efficacy of tolvaptan treatment via nasogastric tube in patients who are unable to respond to thirst by fluid ingestion. Methods: We analyzed 70 consecutive patients with severe congestive heart failure (CHF) who were resistant to loop diuretics and treated with tolvaptan. From the 70 patients, 12 required endotracheal intubation under sedation (Group Tube; GT) and 58 did not (Group Oral; GO). We administered tolvaptan orally in GO; however, in GT, we had to administer tolvaptan via nasogastric tube to achieve pulmonary decongestion quickly. In GT, serum sodium level was monitored closely, and intravenous fluid infusion volume was controlled in the intensive care unit (ICU). Outcomes, including safety and efficacy parameters, were evaluated. Results: In both groups, tolvaptan treatment did not develop a significant rise in serum sodium level compared with baseline, and the incidence of worsening renal failure was comparable, despite greater net fluid loss and higher doses of loop diuretics used in patients of GT compared to GO. In GT, all patients achieved pulmonary decongestion and were weaned from mechanical ventilation. Conclusions: In sedated patients with severe CHF who are unable to respond to thirst by fluid ingestion, tolvaptan can be used without clinically significant hypernatremia under close monitoring in the ICU.
