Thyroid Hormones in Critically Ill Children

Study Overview
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Brief Summary
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Thyroid hormones are substances naturally made by the body and are important to many of your body's basic functions such as breathing and brain function. We are investigating whether or not these hormones are at lower levels in critically ill children which could lead to further health problems. We hope to get a better understanding of hormone levels and their effects on critically ill children to better help other children in the future.

Detailed Description
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We hypothesize that critically ill children that require vasoactive infusions and/or invasive mechanical ventilation have thyroid hormone alterations. We will measure TSH, tT3, fT3, rT3, tT4, fT4, adn tyrosine concentrations in critically ill children with hypotension and/or respiratory failure and correlate thyroid hormone alterations to severity of illness, intensity of therapeutic interventions, and associated morbidity and mortality by using clinical outcomes parameters.

Official Title
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Thyroid Hormone Deficiency in Critically Ill Children

Conditions
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Hypotension, Respiratory Failure

Intervention / Treatment
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* Other: Blood draws


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed Consent Age of less than 12 months and less than or equal to 18 Patient must weigh greater than 10 kgs. Patients must require vasoactive infusions and/or mechanical ventilation. Patients must be enrolled within 24 hours of meeting eligibility. Exclusion Criteria: Patient with known or presumed pre-existing thyroid disease will be excluded Patients who receive thyroid supplementation will be excluded Patients with known or presumed hypothalamic and/or pituitary dysfunction that have thyroid hormone concentration abnormalities not related to an acute illness. Patients who are intubated for airway protection only. Patients intubated for neuromuscular disease Pregnant patients. Patients receiving amiodarone supplementation Patients who received blood product transfusions equaling more than 1/2 of their blood volume.

Ages Eligible for Study
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Minimum Age: 12 Months
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 1<br>Patients who are receiving vasoactive medications and/or are mechanically ventilated. | Other: Blood draws<br>* 17 mls of blood will be drawn over a 5 day period from either a central venous catheter/arterial line or with scheduled phlebotomy. The following labs will be run tT3, fT3, rT#, tT4, fT4, TSH, and tyrosine.<br>* Other names: Thyroid Deficiency;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Certain critically ill children requiring vasoactive infusions and/or mechanical ventilation have low concentrations of tT3, fT3, tT4, fT4, elevated rT3, adn inappropriate low/normal TSH. |  | When patient has completed the study. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Critically ill children with more severe thyroid hormone deficiencies will have greater severity of illness, intensity of therapeutic intervention, organ dysfunction, and increased morbidity and mortality. |  | When study is completed. | 
| Critically ill children requiring vasoactive infusions and/or mechanical ventilation are a population in the ICU that has thyroid hormone pertubation and significant morbidity and mortality. |  | At completion of study | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Thyroid Deficiency, Thyroid Stimulating Hormone