Severe Traumatic Brain Injuries in Children

Severe traumatic brain injury in the pediatric age group is a serious public health problem. Societal goals must prioritize safety in automobiles, bicycles, and sports to prevent primary (physical) injuries. With effective emergency management and expeditious referral to a trauma center with pediatric critical care and neurosurgical expertise, the management and eventual outcome of head injured children can be optimized. Monitoring for, avoiding, and aggressively treating hypoxia, hypotension, and fever are of paramount importance to minimize secondary injury. Routine or prophylactic hyperventilation is no longer considered appropriate. Management specifically geared toward controlling ICP begins with neurosurgical procedures to remove space-occupying lesions and the placement of an ICP monitor. Brain swelling and intracranial hypertension typically progress and peak over a period of several days after the primary injury. First-tier therapy includes sedation and analgesia, drainage of CSF, neuromuscular blockade, hyperosmolar therapy, and mild hyperventilation. Second-tier therapy may include more aggressive hyperventilation, barbiturate-induced coma, hypothermia, lumbar CSF drainage, and decompressive craniectomy in selected cases. Although there is a lack of prospective, randomized, clinical trials in the management of traumatic brain injury in the pediatric population, expert consensus recommendations based on vast empirical experience, some clinical trials, and adult guidelines have been published.     

Pump-regulated cerebrospinal fluid drainage

The drainage of cerebrospinal fluid (CSF) from the lumbar subarachnoid space is an effective technique for the treatment of CSF fistula and control of intracranial pressure in children and adults. The use of the lumbar drain poses unique challenges, however, in the pediatric population. We present a safe and effective method of pump-controlled lumbar subarachnoid drainage. This technique allows accurate titration of CSF removal while providing a closed system which is not sensitive to position changes or patient activity. Four case histories are reviewed.     

Low-pressure shunt 'malfunction' following lumbar puncture in children with shunted obstructive hydrocephalus.

Most shunt malfunctions present with signs and symptoms of high intracranial pressure, and computed tomography scans demonstrate ventricular enlargement. However, several authors have described a rare 'low-pressure' hydrocephalic state in which ventricular enlargement can occur in the face of low, or even negative, intracranial pressures. We report 2 children with obstructive hydrocephalus in whom this 'low-pressure state' followed a lumbar puncture; in both children, the shunts were functioning properly despite increased ventricular size on computed tomography scans, and all symptoms resolved (and the ventricles returned to baseline) following a period of enforced recumbency without shunt revision. We hypothesize that subarachnoid cerebrospinal fluid leakage through the puncture site in the lumbar theca decreases the intracranial pressures globally to a point below the opening pressures of the shunt valves. The ventricular cerebrospinal fluid, unable to be drained through either the subarachnoid space or the shunt, accumulates within the ventricular system under low pressure. One consistent feature in our 2 patients has been the postural nature of the headaches. We recommend enforced recumbency and, if necessary, a blood patch to seal the lumbar leakage. Shunt revision or prolonged external ventricular drainage appears to be unnecessary in these patients. Finally, neurosurgeons should be aware of this potential complication.     

Reliability of cranial CT versus intracerebral pressure measurement for the evaluation of generalised cerebral oedema in children

Objective. To examine the extent to which intracranial pressure (ICP) in children after severe brain trauma can be determined by cranial CT.¶Materials and methods. Two experienced paediatric radiologists, without any knowledge of the clinical symptoms, evaluated 124 CT scans from 65 children (average age 5.4 years) who underwent intracranial measurement of their cerebral pressure.¶Results. CT had high sensitivity (99.1 %) for ’high cerebral pressure' but a much lower specificity (78.1 %). The examiners tended to estimate ICP as ’high' even when actual ICP was low. Since therapy for lowering cerebral pressure involves potential risks, actual cerebral pressure measurement, particularly in children, should be considered before intervention (e. g. hyperventilation or trepanation). We report the change in different intracerebral fluid compartments with varying cerebral pressure and modifications of the density of the brain tissue in an inter- and intraobserver comparison.¶Conclusion. The radiologist cannot differentiate, for methodological reasons, between a change in the intracranial fluid compartments not associated with a change in ICP and one in which it is critically elevated. Before any interventional treatments such as decompression-trepanation or hyperventilation are instituted, measurement of ICP should be considered, especially in children.     

Evaluation of mild head injury in a pediatric population

Approximately 5 million children present to emergency departments, seeking care for head injuries, each year, and 80% of these children are classified as cases of mild head injury. Due to the huge number of patients and low frequency of intracranial lesions in this group, obtaining a computed tomography scan for each and every patient is a significant economic problem. This study was conducted to identify the clinical parameters and the radiographic findings that may be associated with intracranial lesions in children with mild head injury. 421 patients, with a Glasgow Coma Scale score of 15 and without any focal neurological deficit, were studied. Intracranial lesion was noted in 37 cases (8.8%). Sensitivity of a plain radiogram was 43.2%, and specificity was 93%. An intracranial pathology was demonstrated in 28.9% of the patients with a linear skull fracture. The only clinical parameters associated with an increase in the frequency of detection of intracranial lesions were posttraumatic seizures and loss of consciousness. Age, sex, headache, vomiting and scalp lacerations were not associated with a higher frequency. Even when patients with a history of loss of consciousness or posttraumatic seizure were subtracted from the study group, intracranial lesions were noted in 4.1% of the cases, and in 1.8% neurosurgical intervention was required. Computed tomography is the gold standard in the evaluation of pediatric patients with mild head trauma, and every child who has experienced a head injury should undergo a cranial computed tomography evaluation, even if he or she appears in perfect health.     

Erhöhte Konzentrationen des excitotoxischen Neurotransmiters Glutamat im Liquor von Frühgeborenen mit progressiver posthämorrhagischer Ventrikelerweiterung

Objective. Glutamate mediated excitotoxicity is responsible for neuronal injury in a variety of pathologic conditions. As cerebrospinal fluid (CSF) reflects the composition of the extracellular fluid of the brain, CSF-glutamate concentrations were determined in preterm infants with posthemorrhagic ventricular dilatation. Patients and Methods. 16 premature infants at the gestational age of 23–32 weeks who developed progressive posthemorrhagic ventricular dilatation were investigated during the first six months of life. CSF was obtained on 39 occasions by lumbar (n=4) or ventricular (n=23) puncture and during treatment with external drainage (n=12). Results. In 13 CSF samples from 7 patients (44% of the examined preterms) glutamate was increased (>7,2 μM). Extremely high CSF glutamate concentrations of 126 and 77 μM were observed in one patient during ventriculitis and during an episode with excessive increased intracranial pressure (67 cm H₂O). No correlation could be demonstrated between glutamate in the CSF and increased intracranial pressure or parenchym lesions. Elevated concentrations of glutamate in the CSF were associated with increased CSF lactate. Conclusion. These data demonstrate the occurrence of increased CSF glutamate up to the excitotoxic range in preterm infants with progressive posthemorrhagic ventricular dilatation. Glutamate may be part of the final pathway leading to neuronal injury in these patients.     

Elevated nerve growth factor and neurotrophin-3 levels in cerebrospinal fluid of children with hydrocephalus

Background

Elevated intracranial pressure (ICP) resulting from impaired drainage of cerebrospinal fluid (CSF) causes hydrocephalus with damage to the central nervous system. Clinical symptoms of elevated intracranial pressure (ICP) in infants may be difficult to diagnose, leading to delayed treatment by shunt placement. Until now, no biochemical marker of elevated ICP has been available for clinical diagnosis and monitoring. In experimental animal models, nerve growth factor (NGF) and neurotrophin-3 (NT-3) have been shown to be produced by glial cells as an adaptive response to hypoxia. We investigated whether concentrations of NGF and NT-3 are increased in the CSF of children with hydrocephalus.

Methods

NGF was determined in CSF samples collected from 42 hydrocephalic children on 65 occasions (taps or shunt placement surgery). CSF samples obtained by lumbar puncture from 22 children with suspected, but unconfirmed bacterial infection served as controls. Analysis was performed using ELISA techniques.

Results

NGF concentrations in hydrocephalic children were over 50-fold increased compared to controls (median 225 vs 4 pg/mL, p < 0.0001). NT-3 was detectable (> 1 pg/mL) in 14/31 hydrocephalus samples at 2–51 pg/mL but in none of 11 control samples (p = 0.007).

Conclusion

NGF and NT-3 concentrations are increased in children with hydrocephalus. This may represent an adaptive response of the brain to elevated ICP.     

Lumbar CSF shunting preferentially drains the cerebral subarachnoid over the ventricular spaces: implications for the treatment of slit ventricle syndrome

Based on a proposed pathophysiology of slit ventricle syndrome (SVS), we have hypothesized that lumboperitoneal shunting exerts effects in SVS patients by increasing the buffering capacity for raised intracranial pressure (ICP) via an increase in cerebrospinal fluid drainage from the cerebral subarachnoid space (SAS). We describe 3 SVS patients with patent lumbar subarachnoid drainage but under-functioning ventriculoperitoneal shunts (VPS) who presented with ventriculomegaly (not SVS), and persistence of shunt malfunction like symptoms. Revision of the VPS resulted in complete resolution of symptoms despite a finding of low pressure in the ventricular space. This supports the hypothesis that lumboperitoneal shunting preferentially drains the SAS over the intraventricular space and in these cases allows the 'SVS' ventricles to enlarge by creating a pressure gradient from ventricles to SAS through the cortical mantle.     

Serial lumbar punctures for at least temporary amelioration of neonatal posthemorrhagic hydrocephalus

Serial lumbar punctures for the management of neonatal posthemorrhagic hydrocephalus without intracranial hypertension were evaluated in 16 infants. Cranial ultrasonography to evaluate ventricular size and the Ladd monitor at the anterior fontanel to measure intracranial pressure were utilized immediately before and after lumbar puncture. In 12 patients, a decrease in ventricular size and in anterior fontanel pressure could be effected with each lumbar puncture. In these infants, cessation of progression of the hydrocephalus and intermittent decreases in ventricular size were accomplished. In four patients, lumbar punctures were not successful in decreasing ventricular size or lowering intracranial pressure. Two criteria could be defined to determine whether lumbar puncture could provide at least temporary benefit for the treatment of posthemorrhagic hydrocephalus. The first of these is to establish the presence of communication between lateral ventricles and lumbar subarachnoid space by effecting a decrease in ventricular size and a decrease in intracranial pressure by removal of CSF. The second criterion is to ascertain a critical volume of CSF (usually relatively large) that must be removed in order to effect the above changes. Cranial ultrasonography and measurement of intracranial pressure by application of the Ladd monitor to the anterior fontanel are extremely valuable in the evaluation of lumbar punctures in the management of posthemorrhagic hydrocephalus.     

Management of Raised Intracranial Pressure

Appropriate management of raised intracranial pressure begins with stabilization of the patient and simultaneous assessment of the level of sensorium and the cause of raised intracranial pressure. Stabilization is initiated with securing the airway, ventilation and circulatory function. The identification of surgically remediable conditions is a priority. Emergent use of external ventricular drain or ventriculo-peritoneal shunt may be lifesaving in selected patients. In children with severe coma, signs of herniation or acutely elevated intracranial pressure, treatment should be started prior to imaging or invasive monitoring. Emergent use of hyperventilation and mannitol are life saving in such situations. Medical management involves careful use of head elevation, osmotic agents, and avoiding hypotonic fluids. Appropriate care also includes avoidance of aggravating factors. For refractory intracranial hypertension, barbiturate coma, hypothermia, or decompressive craniectomy should be considered.     

Excitatory amino acid concentrations in ventricular cerebrospinal fluid after severe traumatic brain injury in infants and children: the role of child abuse

BACKGROUND: Excitotoxicity is an important mechanism in secondary neuronal injury after traumatic brain injury (TBI). Excitatory amino acids (EAAs) are increased in cerebrospinal fluid (CSF) in adults after TBI; however, studies in pediatric head trauma are lacking. We hypothesized that CSF glutamate, aspartate, and glycine would be increased after TBI in children and that these increases would be associated with age, child abuse, poor outcome, and cerebral ischemia. METHODS: EAAs were measured in 66 CSF samples from 18 children after severe TBI. Control samples were obtained from 19 children who received lumbar punctures to rule out meningitis. RESULTS: Peak and mean CSF glycine and peak CSF glutamate levels were increased versus control values. Subgroups of patients with TBI were compared by using univariate regression analysis. Massive increases in CSF glutamate were found in children <4 years old and in child abuse victims. Increased CSF glutamate and glycine were associated with poor outcome. A trend toward an association between high glutamate concentration and ischemic blood flow was observed. CONCLUSIONS: CSF EAAs are increased in infants and children with severe TBI. Young age and child abuse were associated with extremely high CSF glutamate concentrations after TBI. A possible role for excitotoxicity after pediatric TBI is supported.     

Postural changes in intracranial pressure in chronically shunted patients

A subset of hydrocephalic patients with indwelling shunts become symptomatic when they are upright and active. Intracranial pressure (ICP) measurements in these patients have shown a significant drop in pressure when the patient is upright with return to normal levels when the patient is supine. In 20 chronically shunted hydrocephalic patients who previously had no siphon protection devices, ICP changes in supine and upright position were studied at the time when the patient had external ventriculostomy for treatment of shunt infection. Our hypothesis was that these patients might display rapid changes in ICP from fluid shifts occurring in non-CSF compartments. To minimize the effects of hysteresis, drift and zero-point error, measurements were made using a fluid manometer rather than a strain gauge pressure transducer. The pressure-volume index was estimated using the standard technique of bolus injection. Intracranial CSF volume was estimated on CT scans. The fluid shift was calculated using a mathematical model of the CSF compartment that incorporates negative pressure and volume components that permits simulation of siphoning. Sixteen patients had small, slit ventricles; 3 patients had moderate-sized ventricles and in 1 patient the ventricular size was normal. The average intracranial CSF volume estimated on CT scan was 12 cm(3). There was a mean drop in ICP in the upright position of 159 mm H(2)O. The mean PVI of 42 ml suggested a volume displacement out of proportion to the available intracranial CSF volume. Based on these findings, we conclude that even in the absence of drainage through the shunt, chronically shunted patients still display a fall in ICP when assuming the upright position. This raises the possibility of fluid shifts other than of CSF through nonshunt pathways. Possible mechanisms involving altered CSF-venous system interaction are discussed.     

Pediatric head injury

Pediatric head injury is a public health problem that exacts a high price from patients, their families and society alike. While much of the brain damage in headinjured patients occurs at the moment of impact, secondary injuries can be prevented by aggressive medical and surgical intervention. Modern imaging devices have simplified the task of diagnosing intracranial injuries. Recent advances in monitoring technology have made it easier to assess the effectiveness of medical therapy. These include intracranial pressure monitoring devices that are accurate and safe, and jugular bulb monitoring which provides a continuous, qualitative measure of cerebral blood flow. The cornerstones of treatment remain hyperventilation and osmotherapy. Despite maximal treatment, however, the mortality and morbidity associated with pediatric head injury remains high. Reduction of this mortality and morbidity will likely depend upon prevention rather than treatment.     

A unique pattern of intracranial pressure in a patient with traumatic paroxysmal sympathetic storm

Paroxysmal sympathetic storm (PSS), or diencephalic seizure, usually appears in patients with severe traumatic brain injury and is characterized by various sympathetic symptoms. The physiological effects of this syndrome are not well studied. The authors monitored intracranial pressure (ICP) in a patient with PSS and reviewed its impact on the physiology and management of the syndrome. A 12-year-old male patient was involved in a traffic accident. Upon arrival at the emergency room, his Glasgow Coma Scale score was 5 and he showed decerebration. A brain CT showed an intracerebral hematoma in the right basal ganglia, at which point craniotomy and removal of the hematoma were performed. Continuous intracranial monitoring was performed using the fiber-optic intraparenchymal method. Beginning the day after the trauma, the patient began exhibiting sympathetic symptoms including intermittent episodes of fever, tachycardia, increased blood pressure, tachypnea, diaphoresis and decerebrate rigidity. These episodes were accompanied by ICP elevation of greater than 20 mm Hg. ICP was decreased during hyperventilation, and the episodic symptoms subsided as ICP normalized. PaCO(2) was periodically altered in association with hyperventilation. Electroencephalogram did not show epileptiform discharges, and the sympathetic spells were aborted by continuous intravenous midazolam infusion. The authors report on a pattern of ICP monitoring in association with PSS. Traumatic PSS should be recognized in the appropriate setting to prevent secondary brain damage.     

儿童颅内病变性癫痫影响手术效果的因素分析

目的 对儿童颅内局灶性病变伴癫痫外科治疗后影响其预后的相关因素进行探讨.方法 收集我科自2003年6月至2007年6月间收治的颅内局灶性病变伴癫痫的患儿71例,运用统计学方法对其病理结果、发病至手术时间、发病年龄、手术治疗年龄及脑电图结果等因素与患儿预后的关系进行分析,其预后运用Engel's system进行分级.结果 患儿颅内病变病理性质与其预后无相关,本组病例中各病理组之间对患儿术后癫痫的控制效果无统计学意义.发病至手术时间越短,发病年龄较小,手术治疗越早期,预后较好.VEEG提示放电范围广泛者预后较差,本组病例中术前VEEG监测示痫性放电累及多个脑叶或对侧大脑半球则术后癫痫控制效果较差.结论 对颅内局灶性病变伴癫痫患儿应首选早期手术治疗,VEEG提示放电范围广泛者预后较差.     

Intracranial hypertension in Africans with cerebral malaria

The causes of death and neurological sequelae in African children with cerebral malaria are obscure. Intracranial pressure (ICP) was monitored and cerebral perfusion pressure (CPP) calculated in 23 Kenyan children with cerebral malaria. Four children had severe intracranial hypertension (ICP > 40 mm Hg, CPP < 40 mm Hg): two died, one with an ICP of 158 mm Hg and signs of transtentorial herniation, the other one with an ICP of 42 mm Hg and cardiorespiratory arrest. The other two survived with severe neurological sequelae. Nine had intermediate intracranial hypertension (ICP > 20 mm Hg, CPP < 50 mm Hg) and 10 had mild intracranial hypertension (maximum ICP 10-20 mm Hg); all survived without severe sequelae. Mannitol controlled the ICP in children with intermediate intracranial hypertension, but it did not prevent the development of intractable intracranial hypertension in children with severe intracranial hypertension. Intracranial hypertension is a feature of Kenyan children with cerebral malaria and severe intracranial hypertension is associated with a poor outcome.     

婴幼儿急性颅脑损伤临床分析

目的 探讨3岁以下婴幼儿急性颅脑损伤的特点.方法 回顾性分析49例3岁以下婴幼儿急性颅脑损伤资料,临床主要表现为:抽搐、呕吐、前囱门隆起紧张,意识障碍,局灶性神经系统体征,贫血及呼吸紊乱窘迫.分为三组:轻度颅脑损伤(19例),中度颅脑损伤(22例),重度颅脑损伤(8例),头颅CT显示:①均有颅内出血,包括急性、亚急性硬膜下血肿(SDH)和蛛网膜下腔出血(SAH),最常见出血部位为大脑镰,小脑幕及大脑凸面;②伴局灶性或弥漫性(大面积)脑实质低密度.多发生在6个月以下的婴幼儿,伴大面积低密度灶患儿多预后不良.结果按GOS预后评级,良好39例,中残6例,重残2例,死亡2例.结论 婴幼儿生理特点有其特殊性,依据婴幼儿急性颅脑损伤的特点,早期采取积极有效的治疗措施,可降低病死率及致残率,婴幼儿神经系统修复能力强,与成人相比多预后良好.     

Clinical indicators of intracranial lesion on computed tomographic scan in children with parietal skull fracture

We conducted a review of 98 cases of pediatric traumatic parietal skull fracture in which computed tomographic (CT) scans of the head were obtained during a seven-year period. There were 69 instances of an associated intracranial lesion identified in 47 children, including parenchymal injury (23), epidural hematoma (17), subdural hematoma (11), cerebral edema (ten), and subarachnoid hemorrhage (eight). Compared with 51 other children with parietal skull fracture and normal CT scans, the clinical characteristics significantly associated with the presence of an intracranial lesion were symptoms of neurologic dysfunction (loss or altered level of consciousness and/or seizure activity), neurologic compromise on examination (altered level of consciousness and/or focal deficit), or complicated skull fracture (bilateral, diastatic, and/or depressed). Of the 47 children with an intracranial lesion on CT scan, 44 had at least one of these significant clinical characteristics (sensitivity, 93%; specificity, 50%; positive-predictive value, 62%; and negative-predictive value, 96%). Children who sustain traumatic parietal skull fracture commonly experience associated intracranial injury. Those with evidence of neurologic deficit or complicated skull fracture are at particularly high risk, and should receive cranial CT scan evaluation.     

床旁经颅多普勒超声评估儿童神经危重症患者颅内压的临床价值

目的 研究床旁经颅多普勒超声(transcranial doppler,TCD)在评估儿童重症监护病房(pediatric intensive care unit,PICU)神经危重症患儿颅内压(intracranial pressure,ICP)水平中的应用价值。方法 前瞻性纳入2020年11月至2021年11月入住中国医科大学附属盛京医院PICU的神经危重症患儿进行研究。纳入病例行床旁TCD检查,计算搏动指数(pulsatility index,PI);之后行床旁腰椎穿刺术,测量ICP。采用Pearson相关分析法行PI值与ICP值的相关性分析。采用受试者工作特征(receiver operating characteristic,ROC)曲线评价PI诊断ICP增高(≥20 mm Hg)的价值。结果 56例儿童神经危重症患儿纳入研究。颅内感染(24例,43%)、颅脑创伤(11例,20%)及脑血管疾病(5例,9%)的占比居原发病前3位。Pearson相关分析显示,PI和ICP呈显著正相关(r=0.536,P<0.001)。按原发病分组研究,显示颅脑创伤组PI与ICP呈显著正相关...     

Intracranial pressure and cerebral blood flow velocity in preterm infants with posthaemorrhagic ventricular dilatation

AIM: To determine the volume of cerebrospinal fluid (CSF) that should be tapped in preterm infants with posthaemorrhagic ventricular dilatation as guided by intracranial pressure (ICP) and cerebral blood flow velocity (CBFV). METHODS: The total number of measurements was 106 in 22 infants. Birth weights ranged from 630 to 2050 g, gestational age from 24.5 to 30.3 weeks, and age at insertion from 12 to 67 days. A subcutaneous ventricular catheter reservoir for repetitive CSF drainage was placed when the diameter of a ventricle was > 4 mm above the 97th centile. A volume of 5 ml/kg body weight was removed twice daily. ICP and CBFV were determined before and after CSF tapping. RESULTS: If the ICP after tapping exceeded 7 cm H(2)O, tapping did not result in a significant improvement in CBFV. If the ICP before tapping was less than 6 cm H(2)O, tapping also had no effect on CBFV. Longitudinal studies in individual infants showed a slight correlation between ICP and CBFV. CONCLUSION: Volume of repetitive CSF drainage in preterm infants with posthaemorrhagic ventricular dilatation guided by ICP and CBFV may be a useful technique. An ICP of about 6 cm H(2)O is the cut off point for CSF drainage.