Related Experiment Video
Updated: Jul 28, 2025

In Vitro Thrombosis Test for Ventricular Assist Devices
Published on: March 21, 2025
The Durability of Intravenous Hydroxocobalamin in Vasoplegia
Madeline Blaha1, Meghan Blais1, Logan Olson1
1Department of Pharmacy, Nebraska Medicine, Omaha, USA.
Abstract:
Objectives Refractory distributive shock (vasoplegia) has been treated with intravenous (IV) hydroxocobalamin (B12), but its use is poorly characterized. The objective of this study was to quantify the duration of hemodynamic improvement after B12 administration. Materials and methods This was a retrospective chart review of adult patients who received IV B12 while on vasopressors in the intensive care unit. Patients were divided into two groups: responders (≥10% decrease in baseline vasopressor requirements within 60 minutes of B12 administration) and non-responders. Results A total of 16 patients were included, and five (31%) met the 'responder' criteria. The median time to respond was 15 minutes, and the response was maintained for a median of 210 minutes. The baseline median norepinephrine equivalent (NEE) rate was 32.9 mcg/min in responders and 24.7 mcg/min in non-responders. Responders' NEE requirements decreased to 16.7 mcg/min after 15 minutes and 14.8 mcg/min after 60 minutes. All responders and 10 (91%) non-responders were mechanically ventilated; both groups were mostly male (60% and 91%) and had a median age of 54 years and 58 years, respectively. A total of 4 (80%) responders and 10 (91%) non-responders died while hospitalized. IV B12 was administered as 5 g over 15 minutes in all but two patients (one responder and one non-responder), who each received 5 g of B12 over 360 minutes. Conclusion Vasopressor requirements decreased rapidly in 31% of patients after B12 administration and remained so for a median of 210 minutes.
Related Concept Videos
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Hemodialysis II: Procedure and Complications
Venous Thrombosis III: Interprofessional Care
Hemodialysis I: Introduction
Nonlinear Pharmacokinetics: Drug Elimination for IV Bolus Injection
Following the administration of a single intravenous (IV) bolus injection, we can determine the concentration of the drug in the plasma at any given time. This calculation is achieved using a specific equation that integrates the values of Vmax and KM.
We can also...
Acute Kidney Injury IV: Diagnostic Studies and Prevention

