Performance Evaluation of Pupillary Reactivity in Monitoring of Brain-damaged Patients in Intensive Care

Overview

The pupillary examination is a major component of the clinical examination and monitoring of brain-damaged patients in intensive care. The occurrence of abnormal size or pupillary reactivity is a prognostic factor of poor neurological outcome or an indicator of the neurological status degradation. To date, the monitoring of the pupils is clinical. The subjectivity of this measure and, the lack of reproducibility and definition of the abnormality remain as many obstacles to the development of a monitoring of early neurological deterioration. The recent development in pupillometer electronics allows the assessment of responsiveness to a calibrated light stimulus. It offers a reliable and reproducible measure of the pupil diameter. The pupillometers were funded by the association of " Gueules Cassées ". This study aims to establish a relationship between an abnormal pupillary reactivity detection by the electronic pupillometer and a deterioration in neurological status of the patient brain-damaged in the intensive-care unit (ICU). This is considered clinically relevant and has been defined by a lower Glasgow Coma Score of at least 2 points for 2 hours or involving a therapeutic action. If this relationship is demonstrated, the temporal relationship between data pupillometry and the patient's neurological status remain to be established more precisely. This is particularly relevant in neurosurgical context and aim to define the status of the electronic pupillometer in intensive care but also in emergency rooms services, the neurovascular units or in the pre-hospital care. Therefore the investigators will compare the pupillometry data in two patients groups, defined accordingly to the appearance or absence of neurological aggravation in the first 5 days of treatment in intensive care, time-frame defined as the maximum risk period in patients with brain damage. The primary endpoint is represented by the estimated area under the ROC curve corresponding to the last measure of the change in pupil size before the onset of neurological deterioration and worse for the fifth day for non-aggravated. Thus the investigators propose to conduct a prospective trial, aiming to record the diagnostic value of pupillary reactivity by the electronic pupillometer in the monitoring of the neurological aggravation of brain damaged patient in ICU. The duration of the follow-up for a subject does not exceed 5 days. The statistical analysis requires the recruitment of 90 patients, which sets the length of the inclusions to 14 months.