Intensive care for pediatric traumatic brain injury

PURPOSES

The aims of this study are to describe a cohort of head-injured pediatric patients, focusing on current practice for intracranial pressure (ICP) monitoring and treatment and to verify the relationship between clinical and radiological parameters and the six-month outcome in a multivariable statistical model.

METHODS

A retrospective review was done of a prospectively collected database considering patients younger than 19 years admitted to three neuro-intensive care units (ICU). Patients were divided into four age groups: 0-5 (infant), 6-12 (children), 13-16 (pre-adolescent) and 17-18 years (adolescent). The ICP and cerebral perfusion pressure (CPP) were analyzed calculating average data and values exceeding thresholds for more than 5 min. Outcome was assessed 6 months after trauma using the Glasgow Outcome Score.

RESULTS

There were 199 patients, 155 male, included. Sixty percent had extracranial injuries. Pupils were abnormal in 38 %. Emergency evacuation of intracranial hematomas was necessary in 81 cases. The ICP was monitored in 117 patients; in 87 cases ICP was higher than 20 mmHg, with no differences among age groups. All but six patients received therapy to prevent raised ICP; barbiturates, deep hyperventilation or surgical decompression were used in 31 cases. At 6 months, mortality was 21 % and favorable outcome was achieved by 72 %. Significant predictors of outcome in the multivariable model were the Glasgow Coma Scale (GCS) motor score, pupils and ICP.

CONCLUSIONS

Pediatric head injury is associated with a high incidence of intracranial hypertension. Early surgical treatment and intensive care may achieve favorable outcome in the majority of cases.

Traumatic brain injury in pediatric patients

Traumatic brain injury (TBI) in children is frequent, sometimes lethal, and may have life-long consequences in survivors. Prevention at school and in sports, including both kids and families, is of paramount importance. Scarce data are available in terms of epidemiology, physiopathology, management and prognosis. This non-systematic review suggests that rational organization of rescue and transport to designated hospitals, linked with early diagnosis/removal of surgical masses and comprehensive monitoring and intensive care, offer the best chances for reducing mortality and morbidity in severe cases. After the acute phase rehabilitation and families play a fundamental role.

Hypothermia for brain protection in the non-cardiac arrest patient

This review focuses on the potential application of hypothermia in adults suffering traumatic brain injury (TBI). Hypothermia is neuroprotective, reducing the damaging effects of trauma to the brain in a variety of experimental situations, such as brain ischemia and brain injury, but it has failed to demonstrate outcome improvement in a major controlled, randomized trial. The evidence for the use of hypothermia as a protective procedure is scarce and contradictory. However, evidence does suggest that hypothermia is effective in reducing intracranial hypertension after head injury. Since hypothermia has important side effects, further work is necessary before introducing this procedure into clinical practice for TBI.

[Cerebral oxygen consumption and ischemia in traumatic brain injury]

AIM

Clinical and experimental studies have shown a reduction of cerebral blood flow (CBF) and metabolic alterations following traumatic brain injury (TBI). The incidence of ischemia and the meaning of post-traumatic metabolic alterations are still unclear.

METHODS

Revision of CBF and metabolic changes following TBI based on the literature and on our clinical experience.

RESULTS

Cerebral ischemia and metabolic alterations are part of the secondary insults/damage leading to an increased damage following TBI. Global ischemia occurs early following TBI as shown by CBF measurements and by greater values of arterio-jugular difference of oxygen (AJDO(2)) during the 1(st) 24 hours postinjury. Post-traumatic ischemia should be defined based on the relationships between CBF and on the metabolic requirements of the brain. Regional ischemia occurs more frequently than global ischemia as shown by regional monitoring of cerebral oxygenation. Following TBI there is a transient phase of increased glycolitic activity followed by a more prolonged phase of reduced metabolic rate of glucose (CMRglc) and oxygen (CMRO(2)). The extent of CMRO(2) reduction is a marker of injury severity and it is associated with unfavorable outcome.

CONCLUSION

Cerebral ischemia occurs following TBI and should be defined based on CBF value and the metabolic needs of the brain. Global monitoring of cerebral oxygenation adequacy should be combined with regional monitoring. The meaning of high AJDO(2) values should be reconsidered: if they can highlights potential ischemia they are also showing a still living brain with a partially preserved oxygen extraction capability.

Head injury, subarachnoid hemorrhage and intracranial pressure monitoring in Italy

BACKGROUND

Intracranial pressure monitoring is recommended for the management of severe head injury and is increasingly used during intensive care for other pathologies, such as subarachnoid hemorrhage. However, it is still not uniformly applied in different centers. The objectives of this paper are to summarize the frequency and the modalities of intracranial pressure (ICP) monitoring in different centers in Italy; to describe its use in traumatic brain injury (TBI) and in subarachnoid hemorrhage (SAH); and to identify areas for improvement.

METHODS

The medical directors of either the neurosurgical department or the intensive care unit, or both, of every Italian neurosurgical center were personally interviewed. They answered specific questions about TBI and SAH patients admitted, and ICP monitoring used, in their units. Data were cleared of any obvious inconsistencies and entered in a database for analysis. All analyses were based simply on the data declared.

FINDINGS

The clinical information was obtained from 9137 TBI cases, of whom 4240 severe, and 3151 SAH patients. Among the 106 participating centers, 15 did not use ICP monitoring at all. The remaining 91 had used 3293 ICP devices during the year 2001; 146 were used in tumor cases, 2009 in TBI, and 1138 in SAH. Twenty-two percent of TBI cases admitted to centers with ICP equipment were monitored. Restricting this analysis to severe cases, 47% of TBI with a GCS <8 had ICP. On average, 36% of SAH underwent ICP monitoring. The proportions of head injury and SAH cases who underwent ICP monitoring varied widely in the different centers. Dividing the country into three main areas (north, center and south), there were considerable differences both in the rate of admissions per million inhabitants and in the frequency of ICP monitoring.

INTERPRETATION

ICP monitoring in Italy is used in most, but not all, centers. ICP is measured fairly extensively in head injury cases, but a significant proportion of SAH patients is monitored as well. There are substantial differences in the frequency of ICP monitoring in different parts of the country. The use of ICP for both these indications, and the rates of admission to specialized centers, could be improved.

[How to quantify the severity of brain injury during intensive care after adult head trauma]

Adequate early assessment of brain damage is essential. Location, extension and severity of structural damage affect brain function and ultimately determine the outcome. The extent of functional impairment, and the morphology of intracranial lesions, require specific treatment, often a combination of medical and surgical interventions. Brain damage usually evolves over time, and repeated assessments are necessary. Clinical evaluation is often biased by concomitant sedation and/or anesthesia, but remains necessary. A revision of the literature is presented. Brain damage is assessed combining clinical and instrumental data. Clinical examination is performed assessing the 3 components of the Glasgow Coma Scale. Spontaneous or stimulated (pain stimulus) eye opening, verbal and motor responses are observed after hemodynamic and respiratory stabilisation. Unfortunately a significant proportion of patients can not be properly examined for several reasons: eye opening can be altered by palpebral and facial injuries, verbal response can be impaired by maxillo-facial injuries or by endotracheal intubation, and motor response remains the most consistent parameter. Sedation, analgesia and myorelaxants, however, can profoundly diminish or abolish the motor response to maximal stimulation, so that examination should be performed after clearance of drugs. Often alcohol or other substances can further impair the neurological performances. Pupils diameter and reactivity to light should be observed, excluding pharmacologic effects (as dilation due to catecholamines) and direct ocular or orbital damage. The CT scan is necessary for disclosing surgical masses and for identifying the extent of diffuse damage and the location of focal lesions. These data should be combined with additional functional exploration, as provided by cerebral extraction of oxygen and electrophysiologic data. Early estimation of cerebral damage is complex and prone to mistakes. Accurate, repeated evaluations, based on the combination of clinical observation and imaging, are necessary.