Assessing patients with head injury

Prehospital management of traumatic brain injury

The aim of this study was to review the current protocols of prehospital practice and their impact on outcome in the management of traumatic brain injury. A literature review of the National Library of Medicine encompassing the years 1980 to May 2008 was performed. The primary impact of a head injury sets in motion a cascade of secondary events that can worsen neurological injury and outcome. The goals of care during prehospital triage, stabilization, and transport are to recognize life-threatening raised intracranial pressure and to circumvent cerebral herniation. In that process, prevention of secondary injury and secondary insults is a major determinant of both short- and longterm outcome. Management of brain oxygenation, blood pressure, cerebral perfusion pressure, and raised intracranial pressure in the prehospital setting are discussed. Patient outcomes are dependent upon an organized trauma response system. Dispatch and transport timing, field stabilization, modes of transport, and destination levels of care are addressed. In addition, special considerations for mass casualty and disaster planning are outlined and recommendations are made regarding early response efforts and the ethical impact of aggressive prehospital resuscitation. The most sophisticated of emergency, operative, or intensive care units cannot reverse damage that has been set in motion by suboptimal protocols of triage and resuscitation, either at the injury scene or en route to the hospital. The quality of prehospital care is a major determinant of long-term outcome for patients with traumatic brain injury.

Delayed Intracranial Complications After Concussion

BACKGROUND AND METHODS

The incidence of readmissions because of delayed intracranial complications within 3 weeks after observation for the sole diagnosis of concussion was examined in a national cohort. A nested case-control design was used to analyze the association between clinical factors as well as early computed tomography (CT) scan examination and these complications.

RESULTS

Out of 100,784 patients hospitalized because of concussion during ten years, 127 (0.13%) patients were readmitted because of a delayed intracranial complication. High clinical severity grade (odds ratio [OR] 2.0, confidence interval [CI] 1.2-3.6), minor CT scan abnormalities (OR 1.7, CI 0.8-3.4) and male gender (OR 2.2, CI 1.4-3.5) were associated with an increased risk of delayed, intracranial complications.

CONCLUSION

The incidence of delayed intracranial complications after primarily uncomplicated concussion was low. High clinical severity grade and male gender were risk factors. We failed to demonstrate an additional value of the acute CT scan examination to predict these complications.

Traumatic brain injury outcome: concepts for emergency care

Injury to the brain is the leading factor in mortality and morbidity from traumatic injury. The devastating personal, social, and financial consequences of traumatic brain injury (TBI) are compounded by the fact that most people with TBI are young and previously healthy. From the emergency physician's standpoint, patients with severe TBI are those with a presenting Glasgow Coma Scale score of less than 9. Over the past 30 years, mortality from severe traumatic brain injury for those patients who survive to the hospital has been reduced by half from nearly 50% to approximately 25%. Because most of the pathologic processes that determine outcome are fully active during the first hours after TBI, the decisions of emergency care providers may be crucial. This review addresses new concepts and information in the pathophysiology of TBI and secondary brain injury and demonstrates how emergency management may be linked to neurologic outcome.

L-arginine and superoxide dismutase prevent or reverse cerebral hypoperfusion after fluid-percussion traumatic brain injury

To determine whether treatment with L-arginine or superoxide dismutase (SOD) would prove effective in reducing cerebral hypoperfusion after traumatic brain injury (TBI), we measured cerebral blood flow (CBF) using laser Doppler flowmetry (LDF) in rats treated before or after moderate (2.2 atm) fluid-percussion (FP) TBI. Rats were anesthetized with isoflurane and prepared for midline FP TBI and then for LDF by thinning the calvaria using an air-cooled drill. Rats were then randomly assigned to receive sham injury, sham injury plus L-arginine (100 mg/kg, 5 min after sham TBI), TBI plus 0.9% NaCl, TBI plus L-arginine (100 mg/kg, 5 min post-TBI), TBI plus SOD (24,000 U/kg pre-TBI + 1600 units/kg/min for 15 min after TBI), or TBI plus SOD and L-arginine. A second group of rats received TBI plus saline, L-, or D-arginine (100 mg/kg, 5 min after-TBI). After treatment and TBI or sham injury, CBF was measured continuously using LDF for 2 h and CBF was expressed as a percent of the preinjury baseline for 2 h after TBI. Rats treated with saline or D-arginine exhibited significant reductions in CBF that persisted throughout the monitoring period. Rats treated with L-arginine alone or in combination with SOD exhibited no decreases in CBF after TBI. CBF in the SOD-treated group decreased significantly within 15 min after TBI but returned to baseline levels by 45 min after TBI. These studies indicate that L-arginine but not D-arginine administered after TBI prevents posttraumatic hypoperfusion and that pretreatment with SOD will restore CBF after a brief period of hypoperfusion.

Traumatic brain injury

Traumatic brain injury (TBI) contributes significantly to the mortality and morbidity rates of traumatized patients. This article presents current concepts in the pathophysiology of TBI, including mechanisms of injury, biomolecular mediators of injury, and the occurrence of secondary injury. Emergency management, monitoring, and imaging of TBI also are reviewed.

The use of CT scanning by accident and emergency departments in the UK: past, present and future

To determine the access to and use of computed tomography (CT) scanning by Accident and Emergency (A&E) departments a questionnaire was sent to all major A&E departments in the UK. Although CT scanners were present in over 80 per cent of the 225 responding hospitals, many centres (including 15.8 per cent of those with a CT scanner on site) did not have 24 h scanning facilities for emergency cases. Few departments (26 per cent) have agreed protocols with their radiology departments with regard to CT scanning and some departments transferred cases for emergency CT scans at another hospital. There are deficiencies in access to CT scanning in a significant number of hospitals. This results in some patients undergoing hazardous and in our view unnecessary transfer for scanning. Little use is made of agreed protocols between A&E and Radiology departments to simplify and speed up the process of arranging CT scans. We feel that the deficiencies identified need to be addressed particularly in the assessment of head injury.

Assessment and communication of conscious level: an audit of neurosurgical referrals

Telephone referrals of 100 head-injured patients to a neurosurgical service were assessed to determine if altered consciousness was adequately described by the referring doctor. Of the patients, 60 per cent were resuscitated, assessed and referred by SHOs. Only 30 per cent of doctors were fully conversant with the Glasgow Coma Scale and 18 per cent were unable to describe altered consciousness. Assessment of motor response was often described inaccurately and this was frequently due to the use of an inappropriate stimulus. The use of a pictorial guide to motor responses and a 'Head Injury Proforma' are suggested as means of improving referral and enhancing audit. The majority of doctors had not received formal training in the assessment of conscious level during their undergraduate or postgraduate training. Training video tapes from neurosurgical units showing standard examination methods and typical responses would allow self-assessment and training.

Clinical predictors of abnormality disclosed by computed tomography after mild head trauma

We prospectively studied 712 consecutive patients during a 1-year period who presented with amnesia or loss of consciousness after nonpenetrating head trauma and who had a perfect Glasgow Coma Scale score of 15. Of the 67 (9.4%) patients with acute traumatic lesions disclosed by computed tomography (CT) of the head, 2 required neurosurgical intervention and 1 died. Four factors were statistically correlated (P < 0.05) with abnormal CT findings: Older age, white race, signs of basilar skull fracture, and being either a pedestrian hit by a motor vehicle or a victim of an assault. Sex, length of antero- or retrograde amnesia, forward and reverse digit spans, object recall, focal abnormality on the general neurological exam, and subjective complaints were not statistically correlated with CT abnormality. Using step-wise discriminant function analysis, no single item or combination of items could be used to classify 95% of the patients into either the normal or abnormal CT group. Therefore, regardless of age, mechanism of injury, or clinical findings, intracranial lesions cannot be completely excluded clinically on head-trauma patients who have loss of consciousness or amnesia, even if the Glasgow Coma Scale score is 15. However, only two patients (0.3%) required neurosurgical intervention.