Intravenous Thyroxine for Heart-Eligible Organ Donors

A Multicenter Randomized Placebo-Controlled Trial of Intravenous Thyroxine for Heart-Eligible Brain Dead Organ Donors

This randomized controlled trial will evaluate whether intravenous thyroxine infusion given to brain-dead organ donors who are eligible to donate hearts for 12 hours will result in more hearts transplanted than saline placebo

Background: Brain death frequently induces hemodynamic instability and cardiac stunning. Impairments in cardiac performance are major contributors to hearts from otherwise eligible organ donors not being transplanted. Deficiencies in pituitary hormones (including thyroid stimulating hormone) may contribute to hemodynamic instability and replacement of thyroid hormone has been proposed as a means of improving stability and increasing hearts available for transplantation. Intravenous thyroxine is commonly used in donor management. However, small controlled trials have not been able to demonstrate efficacy. Methods: This multicenter study will involve organ procurement organizations (OPOs) across the country. A total of 800 heart-eligible brain dead organ donors who require vasopressor support will be randomly assigned to intravenous thyroxine for at least 12-hours or saline placebo. The primary study hypothesis is that thyroxine treatment results in more hearts transplanted. Additional outcome measures are time to achieve hemodynamic stability (weaning off vasopressors) and improvement in cardiac ejection fraction on echocardiography. Discussion: This will be the largest randomized controlled study to evaluate the efficacy of thyroid hormone treatment for organ donor management. By collaborating across multiple OPOs, it will be able to enroll an adequate number of donors and be powered to definitively answer the critical question of whether treatment increases hearts transplanted and/or provides other hemodynamic benefits.

Infusion prepared by mixing 500 μg of drug in 500-ml of normal saline (i.e. concentration of 1 μg/ml) and enclosing the bag in an opaque sleeve. Infusion started at 30 μg/hour (30 ml/hour) for twelve hours.

The placebo will be a 500-ml bag of normal saline (without active drug) also enclosed in an opaque sleeve. This infusion will also be started at 30 ml/hour for twelve hours.

Inclusion Criteria: Declared dead by neurologic criteria (brain dead) Authorization for organ donation and research On one or more vasopressors and/or inotropes Exclusion Criteria: Brain death declared more than 24 hours prior Only vasopressor is vasopressin Weight < 45 kg (100 lbs) Known coronary artery disease or history of myocardial infarction Known valvular heart disease Prior sternotomy or cardiac surgery Donor at VA hospital Received intravenous or oral thyroxine within past month Known HIV+ status Other reason donor is unable to receive study drug (determined by on-site personnel)

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Dhar R, Stahlschmidt E, Marklin G. A Randomized Trial of Intravenous Thyroxine for Brain-Dead Organ Donors With Impaired Cardiac Function. Prog Transplant. 2020 Mar;30(1):48-55. doi: 10.1177/1526924819893295. Epub 2019 Dec 5.

Dhar R, Klinkenberg D, Marklin G. A multicenter randomized placebo-controlled trial of intravenous thyroxine for heart-eligible brain-dead organ donors. Trials. 2021 Nov 27;22(1):852. doi: 10.1186/s13063-021-05797-2.