Heart rate variability for assessing comatose patients with different Glasgow Coma Scale scores

October 2012

Yazmina Machado-Ferrer
Mario Estévez
Calixto Machado
Yanín Machado
Philip A. DeFina
…and others.

ABSTRACT: OBJECTIVE: To assess the autonomic nervous system (ANS) in coma by heart rate variability (HRV). METHODS: Sixteen comatose patients and 22 normal subjects with comparable ages and genders were studied. Patients were classified in two subgroups according to the Glasgow Coma Scale (GCS). Time, frequency, and informational HRV domain indices were calculated. RESULTS: A notable reduction of HRV was found in patients. Regarding the time domain indices, the triangular index, and the Delta_RRs, were significantly reduced in the subgroup with GCS=3. Absolute power for the whole frequency spectrum decreased whenever GCS scores were lower. A significant decrement was found for absolute power of the VLF and LF bands in the subgroup of GCS=3, and although it was lower for the HF band in these patients, those changes were not statistically significantly different. The LF/HF ratio and the Shannon´s entropy indices were significantly reduced in the subgroup with GCS=3. Our results are discussed regarding the progressive dysfunction the ANS networks when coma deepens. CONCLUSIONS: The HRV procedure is a powerful tool to assess the ANS in comatose patients. SIGNIFICANCE: HRV is a minimally invasive, low-cost methodology, suitable for assessing the ANS in coma.

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Premio Anual de Salud 2014: Heart rate variability for assessing comatose patients with different Glasgow Coma Scale scores

January 2015

DOI: 10.13140/RG.2.1.3372.5520
Conference: Premio Anual de Salud 2014: Heart rate variability for assessing comatose patients with different Glasgow Coma Scale scores
Project: Autism
Philip A. DeFina
Yazmina Machado-Ferrer
Mario Estévez
Mario Estévez
Calixto Machado
Calixto Machado
…and others.

ABSTRACT: Objective: to assess the autonomic nervous system (ANS) in coma by heart rate variability (HRV). Methods: Sixteen comatose patients and 22 normal subjects with comparable ages and genders were studied. Patients were classified in tow subgroups according to the Glasgow Coma Scale (GCS). Time, frequency, and informational HRV domain indices were calculated. Results: A notable reduction of HRV was found in  patients. Regarding the time domain indices, the triangular index, and the Delta_RRs, were significantly reduced in the subgroup with GCS = 3. Absolute power for the whole frequency spectrum decreased whenever GCS scores were lower. A significant decrement was found for absolute power of the VLF and LF bands in the subgroup of GCS = 3, and although it was lower for the HF band in these patients, those changes were not statistically significantly different. The LF/HF ratio and the Shannons entropy indices were significantly reduced inthe subroup with GCS = 3. Our results are discussed regarding the progressive dysfunction and the ANS networks when coma deepens. Conclusions: The HRV procedure is a powerful tool to assess the ANS in comatose patients. Significance: HRV is a minimally invasive, low-cost methodology, suitable for assessing the ANS in coma.

Click here for a link to the PDF.

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