Targeted ICP reduction in TBI

A South American randomised controlled trial has demonstrated no improvement in mortality when traumatic brain injured patients had therapy targeted at keeping intracranial pressure below or equal to 20 mmHg as measured by an intraparenchymal monitor. The control group’s management was guided by neurologic examination and serial CT imaging(1).

Editorialist Dr Ropper summarises what we should do with this information well(2):

“[The authors]…do not advocate abandoning the treatment of elevated intracranial pressure any more than the authors of studies on wedge pressure reject the administration of fluid boluses in the treatment of shock”

BACKGROUND

Intracranial-pressure monitoring is considered the standard of care for severe traumatic brain injury and is used frequently, but the efficacy of treatment based on monitoring in improving the outcome has not been rigorously assessed.

METHODS
We conducted a multicenter, controlled trial in which 324 patients 13 years of age or older who had severe traumatic brain injury and were being treated in intensive care units (ICUs) in Bolivia or Ecuador were randomly assigned to one of two specific protocols: guidelines-based management in which a protocol for monitoring intraparenchymal intracranial pressure was used (pressure-monitoring group) or a protocol in which treatment was based on imaging and clinical examination (imaging–clinical examination group). The primary outcome was a composite of survival time, impaired consciousness, and functional status at 3 months and 6 months and neuropsychological status at 6 months; neuropsychological status was assessed by an examiner who was unaware of protocol assignment. This composite measure was based on performance across 21 measures of functional and cognitive status and calculated as a percentile (with 0 indicating the worst performance, and 100 the best performance).

RESULTS
There was no significant between-group difference in the primary outcome, a composite measure based on percentile performance across 21 measures of functional and cognitive status (score, 56 in the pressure-monitoring group vs. 53 in the imaging–clinical examination group; P=0.49). Six-month mortality was 39% in the pressure-monitoring group and 41% in the imaging–clinical examination group (P=0.60). The median length of stay in the ICU was similar in the two groups (12 days in the pressure-monitoring group and 9 days in the imaging–clinical examination group; P=0.25), although the number of days of brain-specific treatments (e.g., administration of hyperosmolar fluids and the use of hyperventilation) in the ICU was higher in the imaging–clinical examination group than in the pressure-monitoring group (4.8 vs. 3.4, P=0.002). The distribution of serious adverse events was similar in the two groups.

CONCLUSIONS
For patients with severe traumatic brain injury, care focused on maintaining monitored intracranial pressure at 20 mm Hg or less was not shown to be superior to care based on imaging and clinical examination

1. A Trial of Intracranial-Pressure Monitoring in Traumatic Brain Injury
N Eng J Med 367;26:2471-2381 Full Text

2. Brain in a Box
N Eng J Med DOI: 10.1056/NEJMe1212289 Full Text