Moderate traumatic brain injury, acute phase course and deviations in physiological variables: an observational study.

BACKGROUND: Patients with moderate traumatic brain injury (TBI) are a heterogeneous group with great variability in clinical course. Guidelines for monitoring and level of care in the acute phase are lacking. The main aim of this observational study was to describe injury severity and the acute phase course during the first three days post-injury in a cohort of patients with moderate TBI. Deviations from defined parameters in selected physiological variables were also studied, based on guidelines for severe TBI during the same period. METHODS: During a 5-year period (2004-2009), 119 patients ≥16 years (median age 47 years, range 16-92) with moderate TBI according to the Head Injury Severity Scale were admitted to a Norwegian level 1 trauma centre. Injury-related and acute phase data were collected prospectively. Deviations in six physiological variables were collected retrospectively. RESULTS: Eighty-six percent of the patients had intracranial pathology on CT scan and 61 % had extracranial injuries. Eighty-four percent of all patients were admitted to intensive care units (ICUs) the first day, and 51 % stayed in ICUs ≥3 days. Patients staying in ICUs ≥3 days had lower median Glasgow Coma Scale score; 12 (range 9-15) versus 13 (range 9-15, P = 0.003) and more often extracranial injuries (77 % versus 42 %, P = 0.001) than patients staying in ICU 0-2 days. Most patients staying in ICUs ≥3 days had at least one episode of hypotension (53 %), hypoxia (57 %), hyperthermia (59 %), anaemia (56 %) and hyperglycaemia (65 %), and the proportion of anaemia related to number of measurements was high (33 %). CONCLUSION: Most of the moderate TBI patients stayed in an ICU the first day, and half of them stayed in ICUs ≥3 days due to not only intracranial, but also extracranial injuries. Deviations in physiological variables were often seen in this latter group of patients. Lack of guidelines for patients with moderate TBI may leave these deviations uncorrected. We propose that in future research of moderate TBI, patients might be differentiated with regard to their need for monitoring and level of care the first few days post-injury. This could contribute to improvement of acute phase management.

Moderate and severe traumatic brain injury: effect of blood alcohol concentration on Glasgow Coma Scale score and relation to computed tomography findings.

OBJECT: The influence of alcohol is assumed to reduce consciousness in patients with traumatic brain injury (TBI), but research findings are divergent. The aim of this investigation was to study the effects of different levels of blood alcohol concentration (BAC) on the Glasgow Coma Scale (GCS) scores in patients with moderate and severe TBI and to relate the findings to brain injury severity based on the admission CT scan. METHODS: In this cohort study, 265 patients (age range 16-70 years) who were admitted to St. Olavs University Hospital with moderate and severe TBI during a 7-year period were prospectively registered. Of these, 217 patients (82%) had measured BAC. Effects of 4 BAC groups on GCS score were examined with ordinal logistic regression analyses, and the GCS scores were inverted to give an OR > 1. The Rotterdam CT score based on admission CT scan was used to adjust for brain injury severity (best score 1 and worst score 6) by stratifying patients into 2 brain injury severity groups (Rotterdam CT scores of 1-3 and 4-6). RESULTS: Of all patients with measured BAC, 91% had intracranial CT findings and 43% had BAC > 0 mg/dl. The median GCS score was lower in the alcohol-positive patients (6.5, interquartile range [IQR] 4-10) than in the alcohol-negative patients (9, IQR 6-13; p < 0.01). No significant differences were found between alcohol-positive and alcohol-negative patients regarding other injury severity variables. Increasing BAC was a significant predictor of lower GCS score in a dose-dependent manner in age-adjusted analyses, with OR 2.7 (range 1.4-5.0) and 3.2 (range 1.5-6.9) for the 2 highest BAC groups (p < 0.01). Subgroup analyses showed an increasing effect of BAC group on GCS scores in patients with Rotterdam CT scores of 1-3: OR 3.1 (range 1.4-6.6) and 6.7 (range 2.7-16.7) for the 2 highest BAC groups (p < 0.01). No such relationship was found in patients with Rotterdam CT scores of 4-6 (p = 0.14-0.75). CONCLUSIONS: Influence of alcohol significantly reduced the GCS score in a dose-dependent manner in patients with moderate and severe TBI and with Rotterdam CT scores of 1-3. In patients with Rotterdam CT scores of 4-6, and therefore more CT findings indicating increased intracranial pressure, the brain injury itself seemed to overrun the depressing effect of the alcohol on the CNS. This finding is in agreement with the assumption of many clinicians in the emergency situation.