Observational studyPloS one2021
Is the heart rate variability monitoring using the analgesia nociception index a predictor of illness severity and mortality in critically ill patients with COVID-19? A pilot study.
Observational study in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. It is linked to trial NCT07771101 (Association Between Early Autonomic Dysfunction Measured by the Analgesia Nociception Index), which is not on this map. Cited by 33 papers, 4 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Association Between Early Autonomic Dysfunction Measured by the Analgesia Nociception Index (ANI) and Prolonged Mechanical Ventilation in Postoperative ICU Patients
Who cites it
33 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- Heart rate variability as a marker of multiple organ dysfunction syndromes: a systematic review.Journal of clinical monitoring and computing · 2025Pooled it
- Pooled it
- Wearable Devices to Diagnose and Monitor the Progression of COVID-19 Through Heart Rate Variability Measurement: Systematic Review and Meta-Analysis.Journal of medical Internet research · 2023Pooled it
- The Impact of SARS-CoV-2 Infection on Heart Rate Variability: A Systematic Review of Observational Studies with Control Groups.International journal of environmental research and public health · 2023Pooled it
- Nociception level index monitoring in intensive care: pain awareness in pressure ulcer care in unconscious patients: a randomized controlled pilot study.Irish journal of medical science · 2025Trial
- Significance and Usefulness of High-Resolution 24-h Electrocardiographic Parameters in Patients With Coronavirus Disease 2019 After Admission: A Prospective Cohort Study.Journal of arrhythmia · 2026Article
- Heart Rate Variability as a Biomarker for Posttraumatic Growth: A Comparative Study of Brain Tumor Patients and Caregivers.Cancer medicine · 2026Article
- Heart rate variability in female soccer players, before, during, and after a COVID-19 positive test.Scientific reports · 2025Article
- Pain assessment using the Analgesia Nociception Index in patients undergoing sedation: a systematic review and meta-analysis.The Korean journal of pain · 2025Article
- Heart rate variability parameters indicate altered autonomic tone in subjects with COVID-19.Scientific reports · 2024Article
- Autonomic Function and Baroreflex Control in COVID-19 Patients Admitted to the Intensive Care Unit.Journal of clinical medicine · 2024Article
- Impact of long COVID on the heart rate variability at rest and during deep breathing maneuver.Scientific reports · 2023Article
- Linear and non‑linear indices of vagal nerve in relation to sex and inflammation in patients with Covid‑19.Biomedical reports · 2023Article
- Effects of COVID-19 on the Autonomic Cardiovascular System: Heart Rate Variability and Turbulence in Recovered Patients.Texas Heart Institute journal · 2023Article
- Assessment and Therapeutic Modulation of Heart Rate Variability: Potential Implications in Patients with COVID-19.Journal of cardiovascular development and disease · 2023Review
- The concentrations of essential/toxic elements in serum of COVID-19 patients are not directly related to the severity of the disease.Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) · 2023Article
- Article
- Analgesia nociception index and high frequency variability index: promising indicators of relative parasympathetic tone.Journal of anesthesia · 2023Review
- The validity and applications of the analgesia nociception index: a narrative review.Frontiers in surgery · 2023Review
- Cardiac Autonomic Function in Long COVID-19 Using Heart Rate Variability: An Observational Cross-Sectional Study.Journal of clinical medicine · 2022Article
Corrections and comments
- Erratum issued
Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
introductionThe analysis of heart rate variability (HRV) has proven to be an important tool for the management of autonomous nerve system in both surgical and critically ill patients. We conducted this study to show the different spectral frequency and time domain parameters of HRV as a prospective predictor for critically ill patients, and in particular for COVID-19 patients who are on mechanical ventilation. The hypothesis is that most severely ill COVID-19 patients have a depletion of the sympathetic nervous system and a predominance of parasympathetic activity reflecting the remaining compensatory anti-inflammatory response. MATERIALS AND
methodsA single-center, prospective, observational pilot study which included COVID-19 patients admitted to the Surgical Intensive Care Unit was conducted. The normalized high-frequency component (HFnu), i.e. ANIm, and the standard deviation of RR intervals (SDNN), i.e. Energy, were recorded using the analgesia nociception index monitor (ANI). To estimate the severity and mortality we used the SOFA score and the date of discharge or date of death.
resultsA total of fourteen patients were finally included in the study. ANIm were higher in the non-survivor group (p = 0.003) and were correlated with higher IL-6 levels (p = 0.020). Energy was inversely correlated with SOFA (p = 0.039) and fewer survival days (p = 0.046). A limit value at 80 of ANIm, predicted mortalities with a sensitivity of 100% and specificity of 85.7%. In the case of Energy, a limit value of 0.41 ms predicted mortality with all predictive values of 71.4%.
conclusionA low autonomic nervous system activity, i.e. low SDNN or Energy, and a predominance of the parasympathetic system, i.e. low HFnu or ANIm, due to the sympathetic depletion in COVID-19 patients are associated with a worse prognosis, higher mortality, and higher IL-6 levels.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.