SynthesisJournal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism2022
Reliability and validity of the mean flow index (Mx) for assessing cerebral autoregulation in humans: A systematic review of the methodology.
Synthesis in Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers, 1 of them a synthesis that pooled it.
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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.
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Who cites it
23 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Associations of Cerebrovascular Regulation and Arterial Stiffness With Cerebral Small Vessel Disease: A Systematic Review and Meta-Analysis.Journal of the American Heart Association · 2023Pooled it
- Impact of cardiopulmonary bypass flow on the lower limit of cerebral autoregulation during cardiac surgery: a randomized cross-over pilot study.Journal of clinical monitoring and computing · 2025Trial
- Cerebral oxygenation and hemodynamic changes during ephedrine and phenylephrine administration for transient intraoperative hypotension in patients undergoing major abdominal surgery: a randomized controlled trial.BMC anesthesiology · 2025Trial
- Longitudinal Kinetics of Cerebrospinal Fluid and Serum S100B in Patients with Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage.International journal of molecular sciences · 2026Observational
- Transcranial Doppler ultrasonography in geriatric anesthesia: moving toward personalized brain protection strategies.Anesthesia and pain medicine · 2026Review
- Mean flow index (Mxa) algorithm option can influence cerebral autoregulation classification in critically ill septic patients.Journal of clinical monitoring and computing · 2026Article
- The "SOOTEST-ICU" bundle for optimizing cerebral hypoxia and reperfusion to minimize brain injury after resuscitation from cardiac arrest.World journal of emergency medicine · 2025Article
- Cerebral blood flow dynamics during cardiac surgery in infants.Pediatric research · 2025Article
- Cerebrovascular Autoregulation-Based Optimal Mean Arterial Pressure During Prostate Surgery - A Secondary Analysis of a Prospective Cohort Study.Therapeutics and clinical risk management · 2025Article
- Cerebral autoregulation in pediatric and neonatal intensive care: A scoping review.Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism · 2024Article
- Impaired cerebral autoregulation detected in early prevasospasm period is associated with unfavorable outcome after spontaneous subarachnoid hemorrhage: an observational prospective pilot study.The ultrasound journal · 2024Article
- Myths and methodologies: Assessment of dynamic cerebral autoregulation by the mean flow index.Experimental physiology · 2024Article
- Comparable dynamic cerebral autoregulation and neurovascular coupling of the posterior cerebral artery between healthy men and women.CNS neuroscience & therapeutics · 2024Article
- Intracranial pressure-flow relationships in traumatic brain injury patients expose gaps in the tenets of models and pressure-oriented management.medRxiv : the preprint server for health sciences · 2024Article
- Effect of CGRP inhibitors on interictal cerebral hemodynamics in individuals with migraine.Frontiers in neurology · 2024Article
- Intracranial pressure-flow relationships in traumatic brain injury patients expose gaps in the tenets of models and pressure-oriented management.Frontiers in physiology · 2024Article
- Observational
- Are We Ready for Clinical Therapy based on Cerebral Autoregulation? A Pro-con Debate.Neurocritical care · 2023Article
- Risk of overestimating loss of cerebral autoregulation.BJA open · 2022Article
- Diagnostic and prognostic performance of Mxa and transfer function analysis-based dynamic cerebral autoregulation metrics.Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism · 2022Article
Corrections and comments
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Authors and funding
5 authors.
Funding
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Abstract
Cerebral autoregulation is a complex mechanism that serves to keep cerebral blood flow relatively constant within a wide range of cerebral perfusion pressures. The mean flow index (Mx) is one of several methods to assess dynamic cerebral autoregulation, but its reliability and validity have never been assessed systematically. The purpose of the present systematic review was to evaluate the methodology, reliability and validity of Mx.Based on 128 studies, we found inconsistency in the pre-processing of the recordings and the methods for calculation of Mx. The reliability in terms of repeatability and reproducibility ranged from poor to excellent, with optimal repeatability when comparing overlapping recordings. The discriminatory ability varied depending on the patient populations; in general, those with acute brain injury exhibited a higher Mx than healthy volunteers. The prognostic ability in terms of functional outcome and mortality ranged from chance result to moderate accuracy.Since the methodology was inconsistent between studies, resulting in varying reliability and validity estimates, the results were difficult to compare. The optimal method for deriving Mx is currently unknown.
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