title: Clinical study of continuous non-invasive cerebrovascular autoregulation monitoring in neurosurgical ICU.
abstract: Ultrasonic "time-of-flight" monitor (Vittamed) was used for continuous monitoring of intracranial blood volume (IBV) pulse, respiratory, slow waves and cerebrovascular autoregulation (CA). The objectives are to compare of invasively and non-invasively monitored slow intracranial waves and CA of ICU patients and to evaluate the phase shift between ABP and IBV respiratory waves as a possible estimator of CA. CA monitoring has been performed in 13 patients with severe TBI (age mean/range 30.5/(18-64)). Data were collected from 87 one-hour sessions of simultaneous invasive and non-invasive wave monitoring and from 53 one-hour sessions of invasive and non-invasive CA monitoring. High correlation (R > 0.9) has been obtained between invasively and non-invasively recorded intracranial slow waves. Bland Altman difference between invasively and non-invasively recorded intracranial slow waves is clinically not significant (mean =-0.07, SD = 0.089, alpha = 0.05). Agreement has been confirmed between invasive and non-invasive CA monitoring data in a wide range of R = [-0.85; +0.96]. Hypothesis of the coincidence of invasive and non-invasive CA assessment is accepted (p < 0.05). Phase shift monitoring of permanent respiratory ABP waves and IBV waves permit continuous non-invasive CA estimation without unnatural physical or pharmacological stimulations of CA system.
authors.affiliation: Kaunas University of Technology, Kaunas, Lithuania. telematics@ktu.lt
authors.forename: A
authors.initials: A
authors.lastname: Ragauskas
authors.forename: G
authors.initials: G
authors.lastname: Daubaris
authors.forename: V
authors.initials: V
authors.lastname: Petkus
authors.forename: V
authors.initials: V
authors.lastname: Ragaisis
authors.forename: M
authors.initials: M
authors.lastname: Ursino
mesh_terms: D001794:Blood Pressure; D001921:Brain / Q000098:blood supply; D002560:Cerebrovascular Circulation; D006259:Craniocerebral Trauma / Q000000981:diagnostic imaging*; D003422:Critical Care / Q000379:methods*; D004453:Echoencephalography / Q000379:methods*; D006487:Hemostasis; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007427:Intracranial Pressure; D008991:Monitoring, Physiologic / Q000379:methods*; D009493:Neurosurgery / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity