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Autonomic dysfunction in COVID-19 patients receiving mechanical ventilation: A cross-sectional study
Renata Baltar da Silva1, Victor Ribeiro Neves2, Mayara Costa Barros3
1PT, MSc. Physiotherapist and Doctoral Student, Programa de Pós-Graduação em Ciências da Saúde (PPGCS), Universidade de Pernambuco (UPE), Recife (PE), Brazil. Physiotherapist, Hospital das Clínicas of the Universidade Federal de Pernambuco (HC-UFPE), Empresa Brasileira de Serviços Hospitalares (EBSERH), Recife (PE), Brazil. Physiotherapist, Agamenon Magalhães Hospital (HAM), UPE, Recife (PE), Brazil.
Insights
Mechanical ventilation in intensive care unit patients with Coronavirus disease 2019 (COVID-19) impacts cardiac autonomic control. COVID-19 patients exhibited reduced vagal heart rate variability (HRV) components, suggesting potential clinical implications for cardiac risk.
Area of Science:
- Cardiology
- Intensive Care Medicine
- Autonomic Nervous System Research
Background:
- Coronavirus disease 2019 (COVID-19) is known to cause cardiac damage, evidenced by elevated troponin levels and increased incidence of arrhythmias, myocarditis, and acute coronary syndrome.
- Mechanical ventilation is a critical intervention for severe COVID-19 cases, but its impact on cardiac function, particularly autonomic control, remains an area of investigation.
Purpose of the Study:
- To investigate the effects of COVID-19 on cardiac autonomic control in mechanically ventilated patients within an intensive care unit (ICU) setting.
- To compare heart rate variability (HRV) indices between COVID-19-positive and COVID-19-negative patients undergoing mechanical ventilation.
Main Methods:
- A cross-sectional analytical study was conducted in a tertiary hospital involving mechanically ventilated ICU patients.
- Patients were categorized into COVID-19-positive (COVID(+)) and COVID-19-negative (COVID(-)) groups, with clinical data and HRV recordings collected using a heart rate monitor.
Main Results:
- The study included 82 patients (36 COVID(-) and 46 COVID(+)). Overall HRV indices were lower in mechanically ventilated patients compared to reference values.
- While no significant differences were found in basic HRV intervals (NN, SDNN, RMSSD) between groups, the COVID(+) group showed a statistically significant increase in the low frequency (LF) component (P=0.05), a decrease in the high frequency (HF) component (P=0.045), and an elevated LF/HF ratio (P=0.048).
- A weak positive correlation was observed between the LF/HF ratio and length of stay in the COVID(+) group.
Conclusions:
- Mechanically ventilated patients exhibit diminished overall heart rate variability.
- COVID-19 patients on mechanical ventilation demonstrate reduced vagal components of HRV, indicating impaired autonomic control.
- These findings highlight the clinical relevance of autonomic dysfunction in COVID-19 patients, as such impairments are linked to an increased risk of cardiac mortality.
Background:
Coronavirus disease 2019 (COVID-19) can damage cardiac tissue by increasing troponin levels and inducing arrhythmias, myocarditis, and acute coronary syndrome.
Objectives:
To analyze the impact of COVID-19 on cardiac autonomic control in mechanically ventilated intensive care unit (ICU) patients.
Design And Setting:
This cross-sectional analytical study of ICU patients of both sexes receiving mechanical ventilation was conducted in a tertiary hospital.
Methods:
Patients were divided into COVID-19-positive (COVID(+)) and COVID-19-negative (COVID(-)) groups. Clinical data were collected and heart rate variability (HRV) records obtained using a heart rate monitor.
Results:
The study sample comprised 82 subjects: 36 (44%) in the COVID(-) group (58.3% female; median age, 64.5 years) and 46 (56%) in the COVID(+) group (39.1% females; median age, 57.5 years). The HRV indices were lower than the reference values. An intergroup comparison identified no statistically significant differences in the mean normal-to-normal (NN) interval, standard deviation of the NN interval, or root mean square of successive differences in NN intervals. The COVID(+) group had an increased low frequency (P = 0.05), reduced high frequency (P = 0.045), and increased low frequency/high frequency (LF/HF) ratio (P = 0.048). There was a weak positive correlation between LF/HF and length of stay in the COVID(+) group.
Conclusion:
Patients who received mechanical ventilation had lower overall HRV indices. COVID(+) patients who received mechanical ventilation had lower vagal HRV components. These findings likely indicate clinical applicability, as autonomic control impairments are associated with a greater risk of cardiac death.
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