Long Pressure Autoregulation Index

Conditions

Traumatic Brain Injury

Brief summary

The pressure reactivity index (PRx) has emerged as a surrogate method for the continuous bedside estimation of global cerebral autoregulation and a significant predictor of unfavorable outcomes. However, calculations require continuous, high-resolution monitoring and are currently limited to specialized ICUs with dedicated software. To overcome this problem, new indices calculated using one-minute average data, instead of 10-second average data as performed by the PRx, have been proposed. The study aims to test new physiological indices appropriately modified to adapt to the scarcity of output data generated by standard hospital systems (frequency \ 0.0033 Hz, approximately a 5-minute period) and to evaluate their association with outcome measures.

Detailed description

Data preparation and index calculations were performed using an in-house algorithm. Data extracted and processed with the algorithm: Ultra-low pressure reactivity index (UL-PRx), Intracranial pressure (ICP), Cerebral perfusion pressure (CPP), Arterial blood pressure (ABP), heart rate (HR), respiratory rate (RR), temperature, end-tidal CO2 (EtCO2), saturation (SpO2).

Gritti P, Bonfanti M, Zangari R, Bonanomi E, Di Matteo M, Dell'Avanzo G, Corbella D, Micheli F, Lanterna LA, Lando G, Pezzetti G, Vascello MF, Biroli F, Lorini FL.

2026-01-08

10.1007/s12028-025-02429-4

Continuous monitoring of intracranial pressure and end tidal carbon dioxide variations in traumatic brain injury: introducing the carbon dioxide reactivity index (CO2Rx).

Gritti P, Bonfanti M, Zangari R, Bonanomi E, Di Matteo M, Corbella D, Farina A, Lecchi L, Togni T, Mandelli P, Lanterna LA, Biroli F, Lorini FL.

2025-03-221 citations

10.1007/s10877-025-01285-z

Cerebral autoregulation in traumatic brain injury: ultra-low-frequency pressure reactivity index and intracranial pressure across age groups.

Gritti P, Bonfanti M, Zangari R, Bonanomi E, Farina A, Pezzetti G, Pelliccioli I, Longhi L, Di Matteo M, Viscone A, Lando G, Cavalleri G, Gerevini S, Biroli F, Lorini FL.

2024-01-236 citations

10.1186/s13054-024-04814-5

Evaluation and application of ultra-low-frequency pressure reactivity index in pediatric traumatic brain injury patients.

Gritti P, Bonfanti M, Zangari R, Bonanomi E, Pellicioli I, Mandelli P, Longhi L, Rasulo FA, Bertuetti R, Farina A, Biroli F, Lorini FL.

2023-02-275 citations

10.1007/s00701-023-05538-1

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

RETROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

1 Months to No maximum

Healthy volunteers

No

Inclusion criteria

* Patients with a clinical diagnosis of acute neurological injury requiring intracranial pressure (ICP) monitoring. * Availability of continuous intensive care monitoring of physiological data.

Exclusion criteria

Patients with less than 8 hours of physiological data monitoring.

Design outcomes

Primary

Measure	Time frame	Description
mortality	12-months	The binary outcome of mortality (dead vs alive) during hospitalization and at 12-months
Glasgow Outcome Scale - Extended (GOSE)	12-months	The global functional outcome at 12 months assessed by Glasgow Outcome Scale-Extended (GOS-E), dichotomized into favorable (a score of 5-6 defines a score of 5 to 8, Moderate Disability) and unfavorable (a score of 1 to 4, Dead is characterized by a score of 1).

Countries

Italy

Outcome results