Transcranial Doppler as a screening test to exclude intracranial hypertension in brain-injured patients: the IMPRESSIT-2 prospective multicenter international study
Frank A. Rasulo,
Stefano Calza,
Chiara Robba,
Fabio Silvio Taccone,
Daniele G. Biasucci,
Rafael Badenes,
Simone Piva,
Davide Savo,
Giuseppe Citerio,
Jamil R. Dibu,
Francesco Curto,
Martina Merciadri,
Paolo Gritti,
Paola Fassini,
Soojin Park,
Massimo Lamperti,
Pierre Bouzat,
Paolo Malacarne,
Arturo Chieregato,
Rita Bertuetti,
Raffaele Aspide,
Alfredo Cantoni,
Victoria McCredie,
Lucrezia Guadrini,
Nicola Latronico
Affiliations
Frank A. Rasulo
Department of Anesthesiology, Intensive Care and Emergency, Spedali Civili University Hospital
Stefano Calza
Unit of Biostatistics and Bioinformatics, Department of Molecular and Translational Medicine, University of Brescia
Chiara Robba
Policlinico San Martino, Dipartimento di Scienze Chirurgiche ed Integrate, University of Genoa
Fabio Silvio Taccone
Department of Intensive Care, Erasme Hospital, Universitè Libre de Bruxelles
Daniele G. Biasucci
Neurosurgical Intensive Care, Fondazione Policlinico Universitario “A. Gemelli”, IRCCS
Rafael Badenes
Department of Anesthesiology and Intensive Care, Hospital Clínic Universitari, University of Valencia
Simone Piva
Department of Anesthesiology, Intensive Care and Emergency, Spedali Civili University Hospital
Davide Savo
Neurointensive Care Unit, San Gerardo Hospital, ASST-Monza
Giuseppe Citerio
Neurointensive Care Unit, San Gerardo Hospital, ASST-Monza
Jamil R. Dibu
Cerebrovascular Center of Neurological Institute, Cleveland Clinic
Francesco Curto
Department of Neurointensive Care, Grande Ospedale Metropolitano
Martina Merciadri
Department of Anesthesiology and Critical Care, Azienda Ospedaliera Universitaria Pisana
Paolo Gritti
Department of Anesthesiology and Critical Care, Papa Giovanni XXIII Hospital
Paola Fassini
Department of Anesthesia and Intensive Care, Legnano Hospital
Soojin Park
Division of Critical Care Neurology, Columbia University Irving Medical Center
Massimo Lamperti
Anesthesiology Institute, Cleveland Clinic
Pierre Bouzat
Division of Anesthesiology and Intensive Care
Paolo Malacarne
Department of Anesthesiology and Critical Care, Azienda Ospedaliera Universitaria Pisana
Arturo Chieregato
Department of Neurointensive Care, Grande Ospedale Metropolitano
Rita Bertuetti
Department of Anesthesiology, Intensive Care and Emergency, Spedali Civili University Hospital
Raffaele Aspide
Anesthesia and Intensive Care Unit, Istituto delle Scienze Neurologiche di Bologna
Alfredo Cantoni
Neurointensive Care, ASST-SETTELAGHI
Victoria McCredie
Toronto Western Hospital, University Health Network
Lucrezia Guadrini
Department of Anesthesiology, Intensive Care and Emergency, Spedali Civili University Hospital
Nicola Latronico
Department of Anesthesiology, Intensive Care and Emergency, Spedali Civili University Hospital
Abstract Background Alternative noninvasive methods capable of excluding intracranial hypertension through use of transcranial Doppler (ICPtcd) in situations where invasive methods cannot be used or are not available would be useful during the management of acutely brain-injured patients. The objective of this study was to determine whether ICPtcd can be considered a reliable screening test compared to the reference standard method, invasive ICP monitoring (ICPi), in excluding the presence of intracranial hypertension. Methods This was a prospective, international, multicenter, unblinded, diagnostic accuracy study comparing the index test (ICPtcd) with a reference standard (ICPi), defined as the best available method for establishing the presence or absence of the condition of interest (i.e., intracranial hypertension). Acute brain-injured patients pertaining to one of four categories: traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH) or ischemic stroke (IS) requiring ICPi monitoring, were enrolled in 16 international intensive care units. ICPi measurements (reference test) were compared to simultaneous ICPtcd measurements (index test) at three different timepoints: before, immediately after and 2 to 3 h following ICPi catheter insertion. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated at three different ICPi thresholds (> 20, > 22 and > 25 mmHg) to assess ICPtcd as a bedside real-practice screening method. A receiver operating characteristic (ROC) curve analysis with the area under the curve (AUC) was used to evaluate the discriminative accuracy and predictive capability of ICPtcd. Results Two hundred and sixty-two patients were recruited for final analysis. Intracranial hypertension (> 22 mmHg) occurred in 87 patients (33.2%). The total number of paired comparisons between ICPtcd and ICPi was 687. The NPV was elevated (ICP > 20 mmHg = 91.3%, > 22 mmHg = 95.6%, > 25 mmHg = 98.6%), indicating high discriminant accuracy of ICPtcd in excluding intracranial hypertension. Concordance correlation between ICPtcd and ICPi was 33.3% (95% CI 25.6–40.5%), and Bland–Altman showed a mean bias of -3.3 mmHg. The optimal ICPtcd threshold for ruling out intracranial hypertension was 20.5 mmHg, corresponding to a sensitivity of 70% (95% CI 40.7–92.6%) and a specificity of 72% (95% CI 51.9–94.0%) with an AUC of 76% (95% CI 65.6–85.5%). Conclusions and relevance ICPtcd has a high NPV in ruling out intracranial hypertension and may be useful to clinicians in situations where invasive methods cannot be used or not available. Trial registration: NCT02322970 .
