Sepsis-Dose Hydroxocobalamin as Rescue Therapy for Catecholamine-Resistant Pediatric Septic Shock: A Case Report and Literature Review

Background Sepsis remains a major global cause of mortality, and managing septic shock with refractory hypotension is challenging. Vasodilatory shock, marked by low systemic vascular resistance and normal or elevated cardiac index, is common in sepsis and often responds poorly to standard vasopressors. Case presentation We report a previously healthy 12-year-old boy presented with fever and lethargy and rapidly deteriorated within 24 h, with a decline in the Glasgow Coma Scale (GCS) score to 12/15, profound hypotension (65/33 mmHg), and hypoxemia (SpO₂ 82%). He was tachycardic (147 beats/min) with prolonged capillary refill (>5 s) and was transferred to the pediatric intensive care unit (PICU). After fluid resuscitation (30 mL/kg), norepinephrine was initiated and escalated, and epinephrine and vasopressin were added. Despite therapy, the patient developed progressive shock that required endotracheal intubation and mechanical ventilation. Transpulmonary thermodilution and pulse contour monitoring (PiCCO) were used to guide the targeted hemodynamic management. The pulse pressure and stroke volume variations were both <10%, suggesting limited preload responsiveness. The cardiac index remained within the normal range, whereas the mean arterial pressure and systemic vascular resistance index were markedly reduced, consistent with severe vasoplegia. Hypotension persisted despite high-dose vasopressors (epinephrine, 0.7 µg/kg/min; norepinephrine, 0.8 µg/kg/min, vasopressin 2.4 U/h). Intravenous hydroxycobalamin (≈18 mg/kg over 30 min) was administered as rescue therapy, resulting in a substantial increase in systemic vascular resistance and mean arterial pressure, enabling stepwise weaning from vasopressors. The patient was extubated 36 h later and was dis-charged in good condition on day 5. Conclusion This case highlights hydroxycobalamin as an effective salvage therapy for pediatric vasoplegic shock unresponsive to high-dose vasopressors, improving blood pressure and vascular resistance, enabling vasopressor weaning, and supporting recovery.