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Feasibility of non-invasive neuromonitoring in general intensive care patients using a multi-parameter transcranial Doppler approach

Authors:
Leanne A. Calviello
Leanne A. Calviello
Leanne A. Calviello
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Danilo Cardim at University of Texas Southwestern Medical Center
Danilo Cardim
Marek Czosnyka at University of Cambridge
Marek Czosnyka
Jacobus Preller at Cambridge University Hospitals NHS Foundation Trust
Jacobus Preller
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Purpose To assess the feasibility of Transcranial Doppler ultrasonography (TCD) neuromonitoring in a general intensive care environment, in the prognosis and outcome prediction of patients who are in coma due to a variety of critical conditions. Methods The prospective trial was performed between March 2017 and March 2019 Addenbrooke’s Hospital, Cambridge, UK. Forty adult patients who failed to awake appropriately after resuscitation from cardiac arrest or were in coma due to conditions such as meningitis, seizures, sepsis, metabolic encephalopathies, overdose, multiorgan failure or transplant were eligible for inclusion. Gathered data included admission diagnosis, duration of ventilation, length of stay in the ICU, length of stay in hospital, discharge status using Cerebral Performance Categories (CPC). All patients received intermittent extended TCD monitoring following inclusion in the study. Parameters of interest included TCD-based indices of cerebral autoregulation, non-invasive intracranial pressure, autonomic system parameters (based on heart rate variability), critical closing pressure, the cerebrovascular time constant and indices describing the shape of the TCD pulse waveform. Results Thirty-seven patients were included in the final analysis, with 21 patients classified as good outcome (CPC 1-2) and 16 as poor neurological outcomes (CPC 3-5). Three patients were excluded due to inadequacies identified in the TCD acquisition. The results indicated that irrespective of the primary diagnosis, non-survivors had significantly disturbed cerebral autoregulation, a shorter cerebrovascular time constant and a more distorted TCD pulse waveform (all p<0.05). Conclusions Preliminary results from the trial indicate that multi-parameter TCD neuromonitoring increases outcome-predictive power and TCD-based indices can be applied to general intensive care monitoring.
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ORIGINAL RESEARCH
1 3
Journal of Clinical Monitoring and Computing (2022) 36:1805–1815
https://doi.org/10.1007/s10877-022-00829-x
Danilo Cardim
danilo.cardim@gmail.com
1 Brain Physics Laboratory, Division of Neurosurgery,
Department of Clinical Neurosciences, University of
Cambridge, Cambridge Biomedical Campus, Cambridge,
United Kingdom
2 Department of Neurology, University of Texas Southwestern
Medical Center, Dallas, TX, USA
3 Institute for Exercise and Environmental Medicine, Texas
Health Presbyterian Hospital, Dallas, TX, USA
4 Institute of Electronic Systems, Warsaw University of
Technology, Warsaw, Poland
5 John Farman Intensive Care Unit, Addenbrooke’s Hospital,
Cambridge University Hospitals NHS Foundation,
Cambridge, United Kingdom
6 Department of Neurology and Neurocritical Care Unit,
Addenbrooke’s Hospital, Cambridge University Hospitals
NHS Foundation, Cambridge, United Kingdom
7 Department of Neurology and the Institute for Exercise and
Environmental Medicine, University of Texas Southwestern
Medical Center, Texas Health Presbyterian Hospital, 7232
Greenville Avenue, 75231 Dallas, Texas, USA
Abstract
Purpose To assess the feasibility of Transcranial Doppler ultrasonography (TCD) neuromonitoring in a general intensive
care environment, in the prognosis and outcome prediction of patients who are in coma due to a variety of critical conditions.
Methods The prospective trial was performed between March 2017 and March 2019 Addenbrooke’s Hospital, Cambridge,
UK. Forty adult patients who failed to awake appropriately after resuscitation from cardiac arrest or were in coma due
to conditions such as meningitis, seizures, sepsis, metabolic encephalopathies, overdose, multiorgan failure or transplant
were eligible for inclusion. Gathered data included admission diagnosis, duration of ventilation, length of stay in the ICU,
length of stay in hospital, discharge status using Cerebral Performance Categories (CPC). All patients received intermittent
extended TCD monitoring following inclusion in the study. Parameters of interest included TCD-based indices of cerebral
autoregulation, non-invasive intracranial pressure, autonomic system parameters (based on heart rate variability), critical
closing pressure, the cerebrovascular time constant and indices describing the shape of the TCD pulse waveform.
Results 
-
    
autoregulation, a shorter cerebrovascular time constant and a more distorted TCD pulse waveform (all p<0.05).
Conclusions Preliminary results from the trial indicate that multi-parameter TCD neuromonitoring increases outcome-pre-
dictive power and TCD-based indices can be applied to general intensive care monitoring.
Keywords Cardiac arrest · Cerebral autoregulation · General intensive care · Neuromonitoring · Transcranial Doppler
ultrasonography
Received: 9 December 2021 / Accepted: 2 February 2022 / Published online: 1 March 2022
© The Author(s), under exclusive licence to Springer Nature B.V. 2022
Feasibility of non-invasive neuromonitoring in general intensive care
patients using a multi-parameter transcranial Doppler approach
Leanne A.Calviello1· DaniloCardim1,2,3,7 · MarekCzosnyka1,4· JacobusPreller5· PeterSmielewski1· AnishaSiyal5·
Maxwell S.Damian6
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... A low-flow state defined as MCA MFV below 40 cm/s, occurs in over half of TBI patients during the first 24 h after injury, most often ipsilateral to focal pathology and correlates with the burden of cerebral hypoxia (PbtO 2 <20 mmHg) (155,156). The combination of elevated PI (suggesting increased resistance) with MFV 35-40 cm/s or EDV <20-25 cm/s (signifying impaired CBF) identifies TBI patients with particularly high risk of poor outcome and has even been validated in a mixed ICU population of patients with coma for mortality (152,153,157,158). In addition to prognostication, TCD based thresholds may be used to recognize patients at risk for early deterioration and guide targeted therapy in hopes of preventing cerebral hypoperfusion. ...
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