Eric Zhu, PharmD, RPh
Critical Care Resident (PGY2)
NYU Langone Health
New York, NY
Disclosure information not submitted.
Serena Arnouk, PharmD, BCCCP
Clinical Pharmacotherapy Specialist, Surgical Intensive Care
NYU Langone Medical Center and School of Medicine, United States
Disclosure information not submitted.
Olivia Iskaros, PharmD
PGY2 Critical Care Pharmacy Resident
n/a
New York
Disclosure information not submitted.
Deane Smith, MD
Director, Extracorporeal Membrane Oxygenation Program
NYU Langone Health, United States
Disclosure information not submitted.
John Papadopoulos, BS Pharm, PharmD, FCCM, BCCCP
Director, Clinical Pharmacy Services and Pharmacy Residency Programs
NYU Langone Health
New York, New York, United States
Disclosure information not submitted.
Cristian Merchan, PharmD, BCCCP
Clinical Pharmacotherapy Specialist
NYU Langone, United States
Disclosure information not submitted.
Title: A Comparison of Hydroxocobalamin versus Methylene Blue in Refractory Vasodilatory Shock
Introduction: Vasodilatory shock may arise after cardiopulmonary bypass (CPB) or extracorporeal membrane oxygenation (ECMO) and can require salvage therapy with either hydroxocobalamin (HCB) or methylene blue (MB). Data is limited regarding the optimal agent and dosing strategy for each situation.
Methods: This is a retrospective review of patients who received HCB or MB at NYU Langone Health for refractory vasodilatory shock that occurred within 48 hr after CPB or ECMO cannulation. The primary endpoint was the change in vasopressor requirement at 6, 12, 24, and 48 hr after intervention, characterized as both norepinephrine equivalents (NEE) and vasoactive inotropic score (VIS).
Results: Thirty patients were identified, of which 15 received HCB and 15 received MB. Patients were primarily male (70%) with a median age of 67 and SOFA score of 10. Indications for salvage therapy included postcardiotomy shock (70%) and ECMO cannulation (30%). Dosing strategies included bolus only (9 HCB; 6 MB) or bolus plus infusion (6 HCB; 9 MB), with infusions continuing for a median of 6 hr (5, 6) for HCB and 11 hr (6, 24) for MB. The median cumulative dose was 5000 mg (5000, 10000) for HCB and 5 mg/kg (1.75, 6.8) for MB. Baseline NEE prior to drug administration was 0.42 mcg/kg/min for HCB vs 0.5 mcg/kg/min for MB (p=0.98), and baseline VIS was 28 for HCB vs 23 for MB (p=0.44). Patients who received HCB had a greater percentage change in NEE compared to MB at 6 hr (-72% [-84, -40] vs 0% [-16, +29], p< 0.01) and 12 hr (-73% [-88, -55] vs -39% [-59, +8]; p< 0.01), as well as VIS at 6 hr (-42% [-56, -30] vs 0% [-10, +32]; p< 0.01) and 12 hr (-50% [-78, -32] vs -15% [-41, +17]; p< 0.01). No differences in NEE or VIS were observed at 24 or 48 hr. The bolus plus infusion dosing strategy led to a faster resolution of shock than bolus alone for HCB (27 hr [20, 37] vs 140 hr [98, 436]; p< 0.01) but not for MB (136 hr [30, 251] vs 233 hr [206, 260]; p=0.55). There were no differences in adverse drug events between groups.
Conclusions: We observed greater differences in change in NEE and VIS favoring the use of HCB over MB at 6 and 12 hr, but not at 24 or 48 hr. A HCB dosing strategy of bolus followed by infusion demonstrated a faster resolution of shock in comparison to bolus alone. Further research is required to confirm these results.