Evaluation of optic nerve sheath diameter in hypertensive patients presenting to the emergency department

Introduction and Objectives: It has been found that a large proportion of emergency department patients are hypertension-related presentations. Hypertension affects one in every three adults worldwide and causes increased morbidity and mortality. Hypertension is known to affect intracranial pressure. One of the methods used to evaluate increased intracranial pressure is optic nerve sheath diameter (ONSD) measurement by ultrasonography (USG). The objective of our study was to investigate the success of USG and ONSD values in early diagnosis, treatment follow-up and indication of the need for hospitalization in adult patients admitted to the emergency department with a prediagnosis of hypertensive crisis. Materials and Methods: A case group of 113 patients with a preliminary diagnosis of hypertensive emergency (systolic blood pressure (SBP) ≥180 mmHg and/or diastolic blood pressure (DBP) ≥120 mmHg) who met the inclusion criteria and who were admitted to Afyonkarahisar Health Sciences University Faculty of Medicine, Department of Emergency Medicine, Emergency Department between February 05, 2023 and February 05, 2024 and a control group of 40 patients were included in our study. Age, gender, comorbidities, complaints, blood pressure values at admission and control, organ damage, if any, ONSD values at admission and 1 hour after reaching the target blood pressure after treatment, and outcomes were recorded so as not to cause delay in diagnosis and treatment. Data were transferred to the SPSS® 27.0 for Windows program and statistical analysis was performed. Results: Of the 113 patients included in our study, 63 (55.8%) were female. The mean age of the patients was 61.05±15.23 years. In our study, the comparison of the ONSD measurements of the control group and the case group at the time of emergency department admission was statistically significant (p= 0.006). In our study, a significant statistical correlation was found between shortness of breath and admission ONSD (p=0.009). There was a positive correlation between SBP values and ONSD in hypertensive patient groups (p=0.005). There was a statistically significant correlation between hypertensive patients with and without target organ damage and ONSD at admission (p=0.046). ONSD was found to be higher in the group with target organ damage. There was a significant correlation between the ONSD of hypertensive patients admitted to the emergency department at the time of admission and after treatment (p<0.001). Patients with a diagnosis of hypertensive emergency were found to have statistically significantly higher ONSD on admission than patients with a diagnosis of hypertensive priority condition (p=0.007). When the ONSD at admission was compared between patients with and without a need for hospitalization, it was found that the values of patients with a need for hospitalization were higher (p<0.001). When ROC analysis of the ONSD values at admission for the diagnosis of hypertensive emergency was performed, it was determined that the threshold value was ≥4.6 (Area under the curve (AUC) = 0.686, p=<0.003). When ROC analysis of the ONSD values at admission was performed to predict hospitalization, the threshold value was ≥4.57 (AUC= 0.696, p=<0.001). Conculision: In our study, we suggest that noninvasive, bedside USG measurement of ONSD in patients admitted to the emergency department with a prediagnosis of hypertensive crisis is a practical method for emergency physicians in the differentiation of hypertensive urgent-urgent status, treatment follow-up and hospitalization-discharge decision-making. Keywords: Emergency department, hypertension, hypertensive emergency, hypertensive urgency, increased intracranial pressure, optic nerve sheath diameter, ultrasonography