Unexpected Complication of Hydroxocobalamin Administration for Refractory Vasoplegia in Orthotopic Liver Transplant: A Case Report

Vasoplegia in Heart, Lung, or Liver Transplantation: A Narrative Review

Vasoplegia is a pathophysiologic state of hypotension in the setting of normal or high cardiac output and low systemic vascular resistance despite euvolemia and high-dose vasoconstrictors. Vasoplegia in heart, lung, or liver transplantation is of particular interest because it is common (approximately 29%, 28%, and 11%, respectively), is associated with adverse outcomes, and because the agents used to treat vasoplegia can affect immunosuppressive and other drug metabolism. This narrative review discusses the pathophysiology, risk factors, and treatment of vasoplegia in patients undergoing heart, lung, and liver transplantation. Vasoplegia in this patient population is associated with acute kidney injury, hospital length of stay, and even survival. The mechanisms of vasoplegia in this patient population likely involve multiple pathways, including nitric oxide synthase, cyclic guanylate cyclase, cytokine release, hydrogen sulfide, adrenal axis abnormalities, and vasopressin deficiency. Contributors to vasoplegia in this population include mechanical circulatory support such as extracorporeal membrane oxygenation and cardiopulmonary bypass, organ ischemia time, preexisting infection, and medications such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and excessive sedation. Treatment of vasoplegia in this population begins with conventional catecholamines and vasopressin analogs. Occasionally, agents, including methylene blue, hydroxocobalamin, and angiotensin II, are administered. Though retrospective literature suggests a hemodynamic response to these agents in the transplant population, minimal evidence is available to guide management. In what follows, we discuss the treatment of vasoplegia in the heart, lung, and liver transplant populations based on patient characteristics and potential risk factors associated with non-catecholamine agents.

Hydroxocobalamin for the treatment of vasoplegia after lung transplantation: A case series

Background

The use of hydroxocobalamin following lung transplantation has not been previously reported. We present a series of 3 cases where hydroxocobalamin was used to treat postoperative vasoplegia.

Methods

We conducted a single-center, retrospective review of lung transplantation recipients from January 2016 to December 2020. We used cumulative vasopressor index to standardize vasopressor dose administered and mean arterial pressure at 2- and 24-hour time-points following hydroxocobalamin administration to assess treatment effectiveness.

Results

We identified 3 male patients aged 49 to 62, with lung allocation scores between 89.9 and 90.6, requiring extracorporeal membrane oxygenation support (pre- and post-transplant for 5, 5, 9 and 8, 2, 2 days, respectively). Each patient received hydroxocobalamin 5,000 mg infused over 15 minutes, with patient #3 receiving an additional 6 doses over the subsequent 4 days. At the 2-hour time-point, mean arterial pressure increased in all patients (+11%, +17%, and +13%, respectively), although cumulative vasopressor indexes were inconsistent. At 24 hours, patients #1 and #2 demonstrated a marked increase in mean arterial pressure (36% and 23%, respectively) and a decrease in cumulative vasopressor index, while patient #3 displayed stable with slight reduction in cumulative vasopressor index and mean arterial pressure values. No allergic reactions were observed. Patient #3 developed methemoglobinemia and a medication-related false increase in triglycerides. All 3 patients were discharged home.

Conclusions

Hydroxocobalamin may be a valuable adjunct in managing refractory vasoplegia following lung transplantation.

Use of hydroxocobalamin to treat intraoperative vasoplegic syndrome refractory to vasopressors and methylene blue during liver transplantation

INTRODUCTION

For patients with catecholamine-resistant vasoplegic syndrome (VS) during liver transplantation (LT), treatment with methylene blue (MB) and/or hydroxocobalamin (B12) has been an acceptable therapy. However, data on the effectiveness of B12 is limited to case reports and case series.

METHODS

We retrospectively reviewed records of patients undergoing LT from January 2016 through March 2022. We identified patients with VS treated with vasopressors and MB, and abstracted hemodynamic parameters, vasopressor requirements, and B12 administration from the records. The primary aim was to describe the treatment efficacy of B12 for VS refractory to vasopressors and MB, measured as no vasopressor requirement at the conclusion of the surgery.

RESULTS

One hundred one patients received intraoperative VS treatment. For the 35 (34.7%) patients with successful VS treatment, 14 received MB only and 21 received both MB and B12. Of the 21 patients with VS resolution after receiving both MB and B12, 17 (89.5%) showed immediate, but transient, hemodynamic improvements at the time of MB administration and later showed sustained response to B12.

CONCLUSION

Immediate but transient hemodynamic response to MB in VS patients during LT supports the diagnosis of VS and should prompt B12 administration for sustained treatment response.

Hydroxocobalamin for treatment of catecholamine-resistant vasoplegia during liver transplantation: A single-center series of 20 cases

Introduction

Catecholamine-resistant vasoplegia is a potentially devastating complication during liver transplantation. Hydroxocobalamin has emerged as a treatment for vasoplegia associated with cardiac surgery, liver transplantation, and septic shock.

Presentation of case

We performed a retrospective review of patients who underwent liver transplantation between October 2015 and May 2020 to evaluate the efficiency of hydroxocobalamin in this setting.

Discussion

A total of 137 patients underwent liver transplantation, of which 20 received hydroxocobalamin for vasoplegia. Administration of hydroxocobalamin increased mean arterial pressure and reduced vasoactive drug requirements.

Conclusion

This case series adds to the previous individual reports describing the use of hydroxocobalamin during liver transplantation suggesting hydroxocobalamin can mitigate refractory hypotension from catecholamine resistant vasoplegia during liver transplantation.

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Hypotension or vasoplegia is commonly encountered in end-stage liver disease.

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Vasoplegia during liver transplant is a common and potentially devastating condition.

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Hydroxocobalamin has been reported to improve catecholamine resistant vasoplegia.

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Hydroxocobalamin is believed to work by scavenging gasotransmitters NO, CO, and H₂S.