Autonomic Nervous System Function in Hypoxic-Ischemic Infants Treated With Therapeutic Hypothermia
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 63
- Locations
- 1
- Primary Endpoint
- Heart rate variability (HRV)
Study Overview
Brief Summary
After birth, babies that have suffered from oxygen deprivation may develop hypoxic-ischemic encephalopathy (HIE). Moderate or severe HIE has been associated with death or disability. Therefore, these infants are treated with therapeutic hypothermia (TH), which should be initiated within the first six hours of life. This study aims to investigate the autonomic nervous system (ANS) function of these infants. Thus far, no systematic evaluation of ANS function has been performed, despite its potential in providing important information. Current methods include clinical assessment of pupils size and reactivity, and measurements of heart/respiratory rates. Thus, ANS function evaluation is rather limited and prone to significant inter-examiner variability. This study propose a more comprehensive analysis of ANS function by investigating heart rate variability (HRV) and whole body skin temperature distribution, skin perfusion, axillary and esophageal temperature complexity. The investigators hypothesize that HRV analysis and a more thorough evaluation of ANS function could provide additional information associated with important clinical outcomes, which could eventually be tested clinically.
Detailed Description
- Problem and Hypothesis:
Globally, an estimated 1.8 to 7.7 infants per 1000 live term births suffer from perinatal asphyxia or oxygen deprivation. This remains an important cause of HIE. Seven randomized control trials have demonstrated that therapeutic hypothermia (TH) is a safe and effective therapy for infants with moderate and severe HIE if initiated within the first 6 h of life. TH increases the chances of survival without increasing the rates of neurodevelopmental disability.
Investigations of these infants have focused mainly on daily neurological exams (modified Sarnat Score), electrical activity of the brain (amplitude integrated electroencephalography or aEEG and EEG), and brain imaging. No systematic evaluation of the ANS function has been performed despite its potential in providing important information. Current methods include clinical assessment of pupils size and reactivity, and measurements of heart/respiratory rates and are therefore limited and prone to significant inter-examiner variability. As such, in this study the investigators are planning to performing a more comprehensive analysis of ANS function under the hypothesis that in HIE infants treated with TH; a more thorough analysis of ANS function will provide additional information that can be associated with clinical outcomes. 2. Objectives:
The objectives of the study are to measure and analyze the following variables of ANS function during TH and compare results between infants with and without poor outcomes:
- Heart rate variability (primary outcome)
- Skin temperature distribution and skin perfusion (secondary outcome)
- Axillary temperature complexity (secondary outcome)
- Esophageal temperature complexity (secondary outcome)
A poor outcome will be defined as the composite of death, abnormal neurological exam at the end of the TH period or at discharge or transfer (whichever comes first), and abnormal brain MRI at day of life 10. 3. Methods and Analysis:
Study Design
- Study Type
- Observational
- Observational Model
- Cohort
- Time Perspective
- Prospective
Eligibility Criteria
- Ages
- 1 Hour to 72 Hours (Child)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Patients with Moderate or Severe HIE: 3 or more categories of the modified Sarnat Score in stage 2 or 3 (qualify for therapeutic hypothermia).
- •Patients that are initiated on therapeutic hypothermia.
- •Patients with Mild HIE, not treated with TH (control)
Exclusion Criteria
- •No encephalopathy, defined normal neurological exam.
Outcomes
Primary Outcomes
Heart rate variability (HRV)
Time Frame: 6 months
Heart rate variability (HRV) will be calculated using the time domain and frequency domain analysis and with the HRV module of the Labchart software®.
Secondary Outcomes
- Skin perfusion(6 months)
- Esophageal temperature (Tes)(6 months)
- Whole body skin temperature (WBST)(6 months)
- Axillary temperature (Ta)(6 months)
Investigators
Guilherme Sant'Anna, MD
Associate Professor of Pediatrics
McGill University Health Centre/Research Institute of the McGill University Health Centre