Prolonged hourly neurological examinations are associated with increased delirium and no discernible benefit in mild/moderate geriatric traumatic brain injury

Background: Serial neurological examinations (NEs) are routinely recommended in the intensive care unit (ICU) within the first 24 hours following a traumatic brain injury (TBI). There are currently no widely accepted guidelines for the frequency of NEs. Disruptions to the sleep-wake cycles increase the delirium rate. We aimed to evaluate whether there is a correlation between prolonged hourly (Q1)-NE and development of delirium and to determine if this practice reduces the likelihood of missing the detection of a process requiring emergent intervention.

Methods: A retrospective analysis of patients with mild/moderate TBI, admitted to the ICU with serial NEs, was performed. Cohorts were stratified by the duration of exposure to Q1-NE, into prolonged (≥24 hours) and nonprolonged (<24 hours). Our primary outcomes of interest were delirium, evaluated using the Confusion Assessment Method; radiological progression from baseline images; neurological deterioration (focal neurological deficit, abnormal pupillary examination, or Glasgow Coma Scale score decrease >2); and neurosurgical procedures.

Results: A total of 522 patients were included. No significant differences were found in demographics. Patients in the prolonged Q1-NE group (26.1%) had higher Injury Severity Score with similar head Abbreviated Injury Score, significantly higher delirium rate (59% vs. 35%, p < 0.001), and a longer hospital/ICU length of stay when compared with the nonprolonged Q1-NE group. No neurosurgical interventions were found to be performed emergently as a result of findings on NEs. Multivariate analysis demonstrated that prolonged Q1-NE was the only independent risk factor associated with a 2.5-fold increase in delirium rate. The number needed to harm for prolonged Q1-NE was 4.

Conclusion: Geriatric patients with mild/moderate TBI exposed to Q1-NE for periods longer than 24 hours had nearly a threefold increase in ICU delirium rate. One of five patients exposed to prolonged Q1-NE is harmed by the development of delirium. No patients were found to directly benefit as a result of more frequent NEs.

Level of evidence: Prognostic and Epidemiological; Level IV.