External Ventricular Drains versus Intraparenchymal Intracranial Pressure Monitors in Traumatic Brain Injury: A Prospective Observational Study

Abstract

Intracranial pressure (ICP) monitoring is the standard of care for patients with traumatic brain injury (TBI) and is used frequently. However, the efficacy of treatment based on the type of ICP monitor used for improving patient outcome has not been assessed prospectively. This study explores whether the type of ICP monitoring device used affects the neurologic outcomes of patients with TBI. A prospective, observational study was conducted in 122 patients with TBI ≥13 years old with indications for monitoring who were being treated in neurosurgical intensive care units between January 2009 and December 2012. All enrolled patients required monitoring randomly using an external ventricular drain (EVD) or intraparenchymal fiberoptic monitor (IPM). Patients were placed into 2 groups depending on the type of monitoring device. Clinically relevant outcomes, refractory intracranial hypertension, survival rates, and device-related complications were compared between the 2 groups. There was a significant between-group difference in the Glasgow Outcome Scale score 6 months after injury, which was the primary outcome. Refractory intracranial hypertension was diagnosed in 44 of 122 patients, and patients monitored using IPM had a higher percentage of refractory intracranial hypertension (51.7% vs. 21.0%, P < 0.001). The 1-month survival rate was 90.3% in the EVD group and 76.7% in the IPM group (log-rank test, P= 0.04), and patients managed with EVDs had a significantly higher 6-month postinjury survival rate compared with patients treated with IPMs (88.7% vs. 68.3%, log-rank test, P= 0.006). There was no statistically significant difference between the groups in device-related complications (P= 0.448). Device selection for ICP monitoring provides prognostic discrimination, and use of EVDs may have a bigger advantage in controlling refractory intracranial hypertension. Based on our findings, we recommend routine placement of an EVD in patients with TBI, unless only parenchymal-type monitoring is available.