Clinical Trial: Thyroxine Replacement in Organ Donors

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Efficacy and Pharmacokinetics of Oral Thyroid Replacement Therapy in Organ Donors

Brief Summary: To compare oral versus intravenous administration of thyroid hormone: 1) for reversibility of hemodynamic instability in organ donors, and, 2) the pharmacokinetics of oral vs iv thyroid administration

Detailed Summary:

Disruption of the hypothalamic-pituitary axis following brain death may lead to hemodynamic instability, peripheral vasodilation, and diabetes insipidus in organ donors, requiring the use of high doses of inotropes. Inotropes may cause ischemic injury to organs and intramyocardial ATP stores, resulting in organs unsuitable for transplantation, as well as, a reduction in post-transplant organ function. Therefore, some clinicians advocate the use of triple hormonal therapy in potential organ donors.

Since intravenous T3(the intracellular active form of thyroxine) is unavailable, oral or intravenous T4 must be used, requiring the conversion of T4 to T3at the cellular level. This conversion is impeded by glucocorticoids which also are administered to organ donors for their immunomodulating effects. Since oral T3 is readily available, our first question is whether oral versus intravenous administration of T4 is comparable. If so, our next study is to determine the efficacy of oral T3 versus oral T4. Our hypothesis is oral T3 is superior to oral T4.

Our study therefore will determine whether or not the oral route is suitable for administration of thyroid replacement therapy. The study will compare the pharmacokinetics of oral versus intravenous T4 administration in organ donors, as well as, determine its ability to wean intropes in this patient population.


Sponsor: Lawson Health Research Institute

Current Primary Outcome: Percentage of time patients require inotropic support prior to organ procurement. [ Time Frame: every hour following administration ]

Original Primary Outcome: Percentage of time patients require inotropic support prior to organ procurement.

Current Secondary Outcome:

  • pharmacokinetic profiles of oral vs iv T3,T4 [ Time Frame: hourly from time of administration ]
  • number of organs donated [ Time Frame: total number of organs donated at time of procurement ]
  • thyroid function derangements at time of brain death [ Time Frame: thyroid function q 4hrs following declaration of brain death ]


Original Secondary Outcome:

  • 1. pharmacokinetic profiles of oral vs iv T3,T4
  • 2. number of organs donate
  • 3. thryoid function derangements at time of brain death


Information By: Lawson Health Research Institute

Dates:
Date Received: October 12, 2005
Date Started: December 2004
Date Completion:
Last Updated: January 4, 2011
Last Verified: January 2011