Characterization of intracranial compliance in healthy subjects using a noninvasive method - results from a multicenter prospective observational study

• Published in: Journal of clinical monitoring and computing Vol. 38; no. 6; pp. 1249 - 1261
• Main Authors: Ocamoto, Gabriela Nagai, da Silva, Lucas Normando, da Silva Rocha Tomaz, Camila, Hisatugu, Matheus Toshio, Frigieri, Gustavo, Cardim, Danilo, Gonçalves, Roberta Lins, Russo, Thiago Luiz, de Amorim, Robson Luis Oliveira
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.12.2024; Springer Nature B.V
• Subjects: Adolescent; Adult; Adults; Age; Age Factors; Aged; Anesthesiology; Body size; Child; Compliance; Critical Care Medicine; Female; Health Sciences; Healthy Volunteers; Humans; Intensive; Intracranial Pressure; Male; Medicine; Medicine & Public Health; Men; Middle Aged; Monitoring, Physiologic - methods; Observational studies; Original Research; Prospective Studies; Reference Values; Statistics for Life Sciences; Supine Position; Waveforms; Women; Young Adult; Young adults; Intracranial compliance; Noninvasive monitoring; Adults; Intracranial pressure; Children; Elderly
• ISSN: 1387-1307; 1573-2614; 1573-2614
• DOI: 10.1007/s10877-024-01191-w

Purpose An FDA-approved non-invasive intracranial pressure (ICP) monitoring system enables the assessment of ICP waveforms by revealing and analyzing their morphological variations and parameters associated with intracranial compliance, such as the P2/P1 ratio and time-to-peak (TTP). The aim of this study is to characterize intracranial compliance in healthy volunteers across different age groups. Methods Healthy participants, both sexes, aged from 9 to 74 years old were monitored for 5 min in the supine position at 0º. Age was stratified into 4 groups: children (≤ 7 years); young adults (18 ≤ age ≤ 44 years); middle-aged adults (45 ≤ age ≤ 64 years); older adults (≥ 65 years). The data obtained was the non-invasive ICP waveform, P2/P1 ratio and TTP. Results From December 2020 to February 2023, 188 volunteers were assessed, of whom 104 were male, with a median (interquartile range) age of 41 (29–51), and a median (interquartile range) body mass index of 25.09 (22.57–28.04). Men exhibited lower values compared to women for both the P2/P1 ratio and TTP ( p  < 0.001). There was a relative rise in both P2/P1 and TTP as age increased ( p  < 0.001). Conclusions The study revealed that the P2/P1 ratio and TTP are influenced by age and sex in healthy individuals, with men displaying lower values than women, and both ratios increasing with age. These findings suggest potential avenues for further research with larger and more diverse samples to establish reference values for comparison in various health conditions. Trial registration Brazilian Registry of Clinical Trials (RBR-9nv2h42), retrospectively registered 05/24/2022. UTN: U1111-1266-8006.