2021, Number 6
Optic nerve sheath measurement through computerized scan as death predictor in patients with serious cranioencephalic trauma on entry to the Intensive Care Unit
Language: Spanish
References: 30
Page: 329-335
PDF size: 247.98 Kb.
ABSTRACT
Introduction: Traumatic brain injury (TBI) is a medical-surgical condition characterized by brain involvement secondary to a traumatic lesion. Patients with severe TBI are at high risk of mortality and this will depend on different factors such as the presence of intracranial hypertension, age, origin of the injury and score on the Glasgow coma scale. Measurement of the optic nerve sheath diameter (ONSD) appears to be a good indirect indicator of intercranial hypertension and therefore, a good predictor of mortality. Objective: To determine the most appropriate cut-off point, as well as the measurement of the ONSD usefulness as a prognostic indicator of mortality in patients with severe TBI in the Intensive Care Unit (ICU). Material and methods: This is an analytical, descriptive, and retrospective study. The universe of study consists of all the case/files with TBI. For the sample selection, all available records of patients with severe TBI sent to the ICU during the period from March 1 to August 31, 2021, will be included. Within the inclusion criteria patients with a Glasgow scale score of < 8 points on entry and with a computerized scan done. The dependent variables to considerer are the outcome understood as death or survival of the patient, the days hospitalized in the ICU, the presence of complications; among the dependent variables is the diameter of the optic nerve sheath measured by computerized tomography. Intervening variables were also considered such as the presence of comorbidities and overweight/obesity, the age and sex of the patient. The project consisted of four phases: 1) request for authorization and access to files, 2) application of selection criteria, 3) performance of ONSD measurements and 4) creation of the database. Finally, once the database is formed, the statistical analysis will proceed; for the descriptive part, prevalence's, means (standard deviation) and medians (percentiles) will be calculated for the variables by sex and by outcome, subsequently the diagnostic capacity of the ONSD will be analyzed through the area under the ROC curve (receiving operating characteristics) for the outcome. Afterwards the performance of this and other cut-off points are compared using the Youden index. Results: Sixty records of TBI patients admitted to the ICU were studied, 51 were men (85%), 45 patients survived (75%) and 15 patients died (25%). The average age was of 50.5 ± 10.6 years, the average Glasgow score on admission was 6.6 ± 1.6 points, the average BMI was 26.42 ± 4.10 kg/m2, and the average number of days spent in the ICU was 9.03 ± 6.4. The diameter of the optic nerve was not a predictor of mortality, but if the Glasgow coma scale was, with an AUC of 0.775 (95% CI: 0.648-0.901, p = 0.002), the best cut-off point was 7 with a sensitivity of 93% and specificity of 54%. The bivariate linear regression model points to low Glasgow coma score and long hospital stay as predictors of mortality.Conclusions: The results of this study infer that, consistent with current scientific evidence, the sociodemographic characteristics of our population are similar to those reported by other authors, with men over 50 years of age being the most affected by this entity. On the other hand, the measurement of the diameter of the optic nerve sheath has been considered a good prognostic indicator of intracranial hypertension, which in turn is associated with increased mortality. However, in the present study there is no association between the diameter of the optic nerve sheath and the prognosis of mortality.REFERENCES
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