Hypertonic saline solution and decompressive craniectomy for treatment of intracranial hypertension in pediatric severe traumatic brain injury

Randomized Clinical Trial of 20% Mannitol Versus 3% Hypertonic Saline in Children With Raised Intracranial Pressure Due to Acute CNS Infections

OBJECTIVES

Mannitol is a commonly used osmotherapy agent in raised intracranial pressure. However, the side effects of mannitol are significant. In traumatic brain injury (adult and pediatric), hypertonic saline (3%) shows varied results in comparison with 20% mannitol. We compared the effect of 3% hypertonic saline versus 20% mannitol (using common dosing strategies) on raised intracranial pressure in pediatric acute CNS infections.

DESIGN

Open-label randomized controlled trial.

SETTING

PICU of a quaternary care academic institute.

PATIENTS

Children 1-12 years old, with raised intracranial pressure and modified-Glasgow Coma Scale scores less than or equal to 8, were enrolled.

INTERVENTIONS

Patients were randomly assigned to 20%-mannitol (n = 28), 0.5 gram/kg/dose versus 3%-hypertonic saline (n = 29), 10 mL/kg loading followed by 0.5-1 mL/kg/hr infusion. An intraparenchymal catheter was used to monitor the intracranial pressure. The primary outcome was the proportion of patients achieved target average intracranial pressure less than 20 mm Hg during 72 hours. Secondary outcomes were interventions, morbidity, and mortality.

MEASUREMENTS AND MAIN RESULTS

The proportion of patients with target average intracranial pressure (< 20 mm Hg) was higher in hypertonic saline-group as compared to mannitol-group (79.3% vs 53.6%; adjusted hazard ratio 2.63; 95% CI: 1.23-5.61). Mean (± SE) reduction of intracranial pressure (-14.3 ± 1.7 vs -5.4 ± 1.7 mm Hg; p ≤ 0.001) and elevation of cerebral perfusion pressure (15.4 ± 2.4 vs 6 ± 2.4 mm Hg; p = 0.007) from baseline were significant in hypertonic saline-group. Mean (± SE) intracranial pressure over 72 hours was lower (14 ± 2 vs 22 ± 2 mm Hg; p = 0.009), and cerebral perfusion pressure was higher (65 ± 2.2 vs 58 ± 2.2; p = 0.032) in hypertonic saline-group. Hypertonic saline-group had higher modified-Glasgow Coma Scale score at 72 hours (median, interquartile range 10; 7-11 vs 7; 3-9; p = 0.003), lower mortality (20.7% vs 35.7%; p = 0.21), shorter duration of mechanical ventilation (5 vs 15 d; p = 0.002), and PICU stay (11 vs 19 d; p = 0.016) and less severe neurodisability at discharge (31% vs 61%; p = 0.049).

CONCLUSIONS

In pediatric acute CNS infections, 3%-hypertonic saline was associated with a greater reduction of intracranial pressure as compared to 20% mannitol.

Decompressive craniectomy for the treatment of high intracranial pressure in closed traumatic brain injury

BACKGROUND

High intracranial pressure (ICP) is the most frequent cause of death and disability after severe traumatic brain injury (TBI). It is usually treated with general maneuvers (normothermia, sedation, etc.) and a set of first-line therapeutic measures (moderate hypocapnia, mannitol, etc.). When these measures fail, second-line therapies are initiated, which include: barbiturates, hyperventilation, moderate hypothermia, or removal of a variable amount of skull bone (secondary decompressive craniectomy).

OBJECTIVES

To assess the effects of secondary decompressive craniectomy (DC) on outcomes of patients with severe TBI in whom conventional medical therapeutic measures have failed to control raised ICP.

SEARCH METHODS

The most recent search was run on 8 December 2019. We searched the Cochrane Injuries Group's Specialised Register, CENTRAL (Cochrane Library), Ovid MEDLINE(R), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid OLDMEDLINE(R), Embase Classic + Embase (OvidSP) and ISI Web of Science (SCI-EXPANDED & CPCI-S). We also searched trials registries and contacted experts.

SELECTION CRITERIA

We included randomized studies assessing patients over the age of 12 months with severe TBI who either underwent DC to control ICP refractory to conventional medical treatments or received standard care.

DATA COLLECTION AND ANALYSIS

We selected potentially relevant studies from the search results, and obtained study reports. Two review authors independently extracted data from included studies and assessed risk of bias. We used a random-effects model for meta-analysis. We rated the quality of the evidence according to the GRADE approach.

MAIN RESULTS

We included three trials (590 participants). One single-site trial included 27 children; another multicenter trial (three countries) recruited 155 adults, the third trial was conducted in 24 countries, and recruited 408 adolescents and adults. Each study compared DC combined with standard care (this could include induced barbiturate coma or cooling of the brain, or both). All trials measured outcomes up to six months after injury; one also measured outcomes at 12 and 24 months (the latter data remain unpublished). All trials were at a high risk of bias for the criterion of performance bias, as neither participants nor personnel could be blinded to these interventions. The pediatric trial was at a high risk of selection bias and stopped early; another trial was at risk of bias because of atypical inclusion criteria and a change to the primary outcome after it had started. Mortality: pooled results for three studies provided moderate quality evidence that risk of death at six months was slightly reduced with DC (RR 0.66, 95% CI 0.43 to 1.01; 3 studies, 571 participants; I2 = 38%; moderate-quality evidence), and one study also showed a clear reduction in risk of death at 12 months (RR 0.59, 95% CI 0.45 to 0.76; 1 study, 373 participants; high-quality evidence). Neurological outcome: conscious of controversy around the traditional dichotomization of the Glasgow Outcome Scale (GOS) scale, we chose to present results in three ways, in order to contextualize factors relevant to clinical/patient decision-making. First, we present results of death in combination with vegetative status, versus other outcomes. Two studies reported results at six months for 544 participants. One employed a lower ICP threshold than the other studies, and showed an increase in the risk of death/vegetative state for the DC group. The other study used a more conventional ICP threshold, and results favoured the DC group (15.7% absolute risk reduction (ARR) (95% CI 6% to 25%). The number needed to treat for one beneficial outcome (NNTB) (i.e. to avoid death or vegetative status) was seven. The pooled result for DC compared with standard care showed no clear benefit for either group (RR 0.99, 95% CI 0.46 to 2.13; 2 studies, 544 participants; I2 = 86%; low-quality evidence). One study reported data for this outcome at 12 months, when the risk for death or vegetative state was clearly reduced by DC compared with medical treatment (RR 0.68, 95% CI 0.54 to 0.86; 1 study, 373 participants; high-quality evidence). Second, we assessed the risk of an 'unfavorable outcome' evaluated on a non-traditional dichotomized GOS-Extended scale (GOS-E), that is, grouping the category 'upper severe disability' into the 'good outcome' grouping. Data were available for two studies (n = 571). Pooling indicated little difference between DC and standard care regarding the risk of an unfavorable outcome at six months following injury (RR 1.06, 95% CI 0.69 to 1.63; 544 participants); heterogeneity was high, with an I2 value of 82%. One trial reported data at 12 months and indicated a clear benefit of DC (RR 0.81, 95% CI 0.69 to 0.95; 373 participants). Third, we assessed the risk of an 'unfavorable outcome' using the (traditional) dichotomized GOS/GOS-E cutoff into 'favorable' versus 'unfavorable' results. There was little difference between DC and standard care at six months (RR 1.00, 95% CI 0.71 to 1.40; 3 studies, 571 participants; low-quality evidence), and heterogeneity was high (I2 = 78%). At 12 months one trial suggested a similar finding (RR 0.95, 95% CI 0.83 to 1.09; 1 study, 373 participants; high-quality evidence). With regard to ICP reduction, pooled results for two studies provided moderate quality evidence that DC was superior to standard care for reducing ICP within 48 hours (MD -4.66 mmHg, 95% CI -6.86 to -2.45; 2 studies, 182 participants; I2 = 0%). Data from the third study were consistent with these, but could not be pooled. Data on adverse events are difficult to interpret, as mortality and complications are high, and it can be difficult to distinguish between treatment-related adverse events and the natural evolution of the condition. In general, there was low-quality evidence that surgical patients experienced a higher risk of adverse events.

AUTHORS' CONCLUSIONS

Decompressive craniectomy holds promise of reduced mortality, but the effects of long-term neurological outcome remain controversial, and involve an examination of the priorities of participants and their families. Future research should focus on identifying clinical and neuroimaging characteristics to identify those patients who would survive with an acceptable quality of life; the best timing for DC; the most appropriate surgical techniques; and whether some synergistic treatments used with DC might improve patient outcomes.

Decompressive craniectomy in children: single-center series and systematic review

BACKGROUND

Decompressive craniectomy (DC) is performed as a life-saving procedure in patients with intractably increased intracranial pressure after traumatic brain injury, bleeding, cerebral infarction, or brain swelling of other causes. However, the application of DC is as controversial in the pediatric population as it is in adults.

OBJECTIVE

To find factors influencing the outcome in pediatric patients who underwent DC because of sustained high intracranial pressure.

METHODS

Between April 2000 and December 2009, 34 pediatric patients (age 0-18 years) underwent DC. Patients were stratified according to the indication for DC. Outcome was assessed according to the modified Rankin Scale score at 6 months. MEDLINE was searched for published studies or reports of DC in pediatric patients to gain a larger population. Two reviewers independently extracted data.

RESULTS

Literature data, including the current series, revealed a total of 172 pediatric patients. Overall, a favorable outcome was achieved in 106 of 172 patients (62%). A favorable outcome was achieved in 25 of 36 patients without traumatic brain injury vs 81 of 136 patients with traumatic brain injury (69% vs 60%). Patients without signs of cerebral herniation had a better outcome than patients with unilateral or bilateral dilated pupils (73% vs 60% vs 45%, respectively).

CONCLUSION

The current data indicate that DC in children with traumatic or nontraumatic brain swelling might be warranted, regardless of the underlying cause. Despite mydriasis, a favorable outcome might be achieved in a significant number of pediatric patients. Nevertheless, careful individual decision making is needed for each patient, especially when signs of cerebral herniation have persisted for a long time.

Hypertonic saline for treating raised intracranial pressure: literature review with meta-analysis

Object

Currently, mannitol is the recommended first choice for a hyperosmolar agent for use in patients with elevated intracranial pressure (ICP). Some authors have argued that hypertonic saline (HTS) might be a more effective agent; however, there is no consensus as to appropriate indications for use, the best concentration, and the best method of delivery. To answer these questions better, the authors performed a review of the literature regarding the use of HTS for ICP reduction.

Methods

A PubMed search was performed to locate all papers pertaining to HTS use. This search was then narrowed to locate only those clinical studies relating to the use of HTS for ICP reduction.

Results

A total of 36 articles were selected for review. Ten were prospective randomized controlled trials (RCTs), 1 was prospective and nonrandomized, 15 were prospective observational trials, and 10 were retrospective trials. The authors did not distinguish between retrospective observational studies and retrospective comparison trials. Prospective studies were considered observational if the effects of a treatment were evaluated over time but not compared with another treatment.

Conclusions

The available data are limited by low patient numbers, limited RCTs, and inconsistent methods between studies. However, a greater part of the data suggest that HTS given as either a bolus or continuous infusion can be more effective than mannitol in reducing episodes of elevated ICP. A meta-analysis of 8 prospective RCTs showed a higher rate of treatment failure or insufficiency with mannitol or normal saline versus HTS.

Operational anaesthesia for the management of traumatic brain injury

The primary brain insult that occurs at the time of head injury, is determined by the degree of neuronal damage or death and so cannot be influenced by further treatment. The focus of immediate and ongoing care from the point of wounding to intensive care management at Role 4 should be to reduce or prevent any secondary brain injury. The interventions and triage decisions must be reassessed at every stage of the process, but should focus on appropriate airway management, maintenance of oxygenation and carbon dioxide levels and maintenance of adequate cerebral perfusion pressure. Early identification of raised intracranial pressure and appropriate surgical intervention are imperative. Concurrent injuries must also be managed appropriately. Attention to detail at every stage of the evacuation chain should allow the head-injured patient the best chance of recovery.

Decompressive hemicraniectomy for pediatric traumatic brain injury: long-term outcome based on quality of life

AIMS

The impact of decompressive hemicraniectomy (DCH) on the overall outcome of pediatric brain injury patients has not been fully determined. In this paper, the authors performed a systematic review of patient outcome based on quality of life following DCH in a pediatric population.

METHODS

We describe our experience with decompressive craniectomy in pediatric patients and perform a literature review and pooled outcomes analysis to supplement these findings. A total of 13 children underwent DCH for intractable intracranial pressure in our institution from 2000 to 2008. Follow-up was available in 11 patients with 1 death (9%) and 7 survivors (70%) obtaining a favorable outcome (Glasgow Outcome Scale, GOS, scores = 4-5).

RESULTS

A literature review to determine the usefulness of DCH identified 17 articles that, when combined with our series, resulted in 186 pediatric DCH cases. Pooled outcomes found 42 deaths and 112 patients who had favorable outcomes at 6 months. The average 6-month mortality was 21.1%, and the pooled mean quality of life among survivors 0.75 (0.68-0.82), midway between moderate disability and good outcome.

CONCLUSIONS

Based on our findings, DCH results in a majority of pediatric patients having a good outcome based on the GOS score.

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.

The role for osmotic agents in children with acute encephalopathies: a systematic review

BACKGROUND

Raised intracranial pressure (ICP) is known to complicate both traumatic and non-traumatic encephalopathies. It impairs cerebral perfusion and may cause death due to global ischaemia and intracranial herniation. Osmotic agents are widely used to control ICP. In children, guidelines for their use are mainly guided by adult studies. We conducted this review to determine the current evidence of the effectiveness of osmotic agents and their effect on resolution of coma and outcome in children with acute encephalopathy.

METHODS

We searched several databases for published and unpublished studies in English and French languages, between January 1966 and March 2009. We considered studies on the use of osmotic agents in children aged between 0 and 16 years with acute encephalopathies. We examined reduction in intracranial pressure, time to resolution of coma, and occurrence of neurological sequelae and death.

RESULTS

We identified four randomized controlled trials, three prospective studies, two retrospective studies and one case report. Hypertonic saline (HS) achieved greater reduction in intracranial pressure (ICP) compared to mannitol and other fluids; normal saline or ringer's lactate. This effect was sustained for longer when it was given as continuous infusion. Boluses of glycerol and mannitol achieved transient reduction in ICP. Oral glycerol was associated with lower mortality and neurological sequelae when compared to placebo in children with acute bacterial meningitis. HS was associated with lower mortality when compared to mannitol in children with non-traumatic encephalopathies.

CONCLUSION

HS appears to achieve a greater reduction in ICP than other osmotic agents. Oral glycerol seems to improve outcome among children with acute bacterial meningitis. A sustained reduction in ICP is desirable and could be achieved by modifying the modes and rates of administration of these osmotic agents, but these factors need further investigation.

The Role for Osmotic Agents in Children with Acute Encephalopathies: A Systematic Review

BACKGROUND

Raised intracranial pressure (ICP) is a common complication in children with acute encephalopathies. It compromises cerebral perfusion leading to ischaemia and may cause death when the brainstem is compressed during trans-tentorial herniation. Osmotic agents are widely used to control raised ICP. Their use in children is mainly guided by studies in adults.

OBJECTIVE

We carried out this review to determine the best available evidence of the effectiveness of various osmotic agents and their effect on resolution of coma and outcome (neurological sequelae and mortality) in children with acute encephalopathies.

SELECTION CRITERIA

We searched literature published between January 1966 and January 2008 on the use of osmotic agents in children aged between 0 and 16 years with acute encephalopathies.

SEARCH STRATEGY

We searched Medline, Cochrane Library, EMBASE, Cumulative Index to Nursing and Allied Health Literature and other databases for both published and unpublished literature.

RESULTS

We identified four randomized controlled trials (RCTs), three prospective observational studies, two retrospective studies and one case report. The use of hypertonic saline appeared to achieve greater reduction in ICP compared to mannitol, normal saline and ringer's lactate. This effect was sustained when it was given as a continuous infusion. Boluses of glycerol and mannitol achieved transient reduction in ICP. Use of repeated doses of oral glycerol was associated with lower mortality and neurological sequelae when compared to placebo in children with acute bacterial meningitis. Hypertonic saline was associated with lower mortality when compared to mannitol in children with non-traumatic encephalopathies.

DISCUSSION

All agents resulted in reduction of ICP, albeit transient in a number of occasions. A sustained reduction in ICP is desirable and could be achieved by modifying the modes and rates of administration, factors that need further investigation. Hypertonic saline appears to boost cerebral perfusion pressure, an important determinant of outcome in acute encephalopathies.

CONCLUSION

Hypertonic saline appears to achieve greater reduction in ICP than other osmotic agents. Oral glycerol seems to improve outcome among children with acute bacterial meningitis. However, the evidence is not sufficient to guide change of practice. More studies are needed to examine the safest and most efficacious concentrations of the various agents and the most effective routes and rates of administration of these agents.

Pediatric traumatic brain injury: an update of research to understand and improve outcomes

PURPOSE OF REVIEW

Traumatic brain injury is the leading cause of death in the pediatric population. The purpose of this review is to highlight recent contributions in evaluation, management, and predictors of outcome in pediatric traumatic brain injury.

RECENT FINDINGS

Advances have been made in defining the critical Glasgow Coma Score for predicting poor outcome and in developing the Relative Head Injury Severity Score, which can assess severity of traumatic brain injury from administrative datasets. More information regarding the radiation risks of head computed tomography imaging and guidelines for the appropriate use of imaging have recently been evaluated. Important steps have also been taken to reduce secondary brain injury through the use of hypertonic saline and induced hypothermia. There continues to be long-term neurodevelopmental deficits among survivors and new tools to assess these deficits have been developed and tested. Finally, increased investigation into understanding the impact of minority race and socioeconomic status has on outcome following traumatic brain injury has determined the existence of disturbing disparities.

SUMMARY

Traumatic brain injury is the leading cause of mortality and is a major public health issue in the pediatric population. There have been many recent contributions in the diagnosis, treatment, and long-term morbidity of traumatic brain injury. Ongoing work is needed to improve outcomes of traumatic brain injury equitably for all patients.

Effect of hypertonic saline concentration on cerebral and visceral organ water in an uninjured rodent model

OBJECTIVE

Hypertonic saline has been shown to be an effective osmotic agent to reduce brain water and hence brain volume and intracranial pressure. A direct correlation between dose and effect has been demonstrated, but no studies have compared the effects of different concentrations of the same osmotic load of hypertonic saline over time. We compared the effects of different tonicity of infused hypertonic saline on cerebral, lung, and small bowel water extraction over time under controlled conditions.

DESIGN

Laboratory study.

SETTING

Medical school.

SUBJECTS

Male Wistar rats (280-450 g).

INTERVENTIONS

Anesthetized rats were randomized to a 15-min intravenous bolus infusion of 0.9% NaCl or five equisodium but different concentrations of hypertonic saline: 4.2%, 7.5%, 10%, 23.4%, and 30%. Following infusion, animals remained anesthetized for 60, 180, or 300 mins without additional fluids given (n > or = 6 per group). Blood was sampled, total urine output was measured, and the animal was then killed under deep anesthesia. Cerebral, lung, and small bowel water contents were derived by wet/dry weight measures.

MEASUREMENTS AND MAIN RESULTS

After 60 mins, hypertonic saline administered at 50 mosm/kg resulted in an increase in serum osmolarity in all hypertonic saline groups (p < .05 vs. normal saline), with a significantly greater increase measured using 23.4% or 30% hypertonic saline (23.4%, 365.0 +/- 8.8 mosm/L, p < .05 vs. other lesser hypertonic saline doses). The durable effect was present throughout the 300-min period by all but the lowest hypertonic saline (4.2% NaCl). Lung but not small bowel organ water was diminished by hypertonic saline. Brain water content (79.1 +/- 0.2% in normal saline controls) was, however, significantly reduced.

CONCLUSIONS

Hypertonic saline is effective in reducing organ water content in a setting of preserved blood-brain barrier but is not as effective in visceral organs. At equiosmotic doses of hypertonic saline, concentration plays no substantial role in altering serum osmolarity but appears to benefit duration of action. At very high concentrations, such as 23.4% NaCl, additional water extraction is also manifested. At such high concentration of NaCl, tonicity, indeed, matters, especially in water shifts across the blood-brain barrier.

Hypertonic saline: a clinical review

Literature suggest that hypertonic saline (HTS) solution with sodium chloride concentration greater than the physiologic 0.9% can be useful in controlling elevated intracranial pressure (ICP) and as a resuscitative agent in multiple settings including traumatic brain injury (TBI). In this review, we discuss HTS mechanisms of action, adverse effects, and current clinical studies. Studies show that HTS administered during the resuscitation of patients with a TBI improves neurological outcome. HTS also has positive effects on elevated ICP from multiple etiologies, and for shock resuscitation. However, a prospective randomized Australian study using an aggressive resuscitation protocol in trauma patients showed no difference in amount of fluids administered during prehospital resuscitation, and no differences in ICP control or neurological outcome. The role of HTS in prehospital resuscitation is yet to be determined. The most important factor in improving outcomes may be prevention of hypotension and preservation of cerebral blood flow. In regards to control of elevated ICP during the inpatient course, HTS appears safe and effective. Although clinicians currently use HTS with some success, significant questions remain as to the dose and manner of HTS infusion. Direct protocol comparisons should be performed to improve and standardize patient care.

Outcome following decompressive craniectomy in children with severe traumatic brain injury: a 10-year single-center experience with long-term follow up

OBJECT

The authors examine the indications for and outcomes following decompressive craniectomy in a single-center pediatric patient population with traumatic brain injury (TBI).

METHODS

A retrospective review of data was performed using a prospectively acquired database of patients who underwent decompressive craniectomy at the authors' institution between January 1995 and April 2006. The patients' neuroimages were examined to evaluate the extent of intracranial injury, and the patients' records were reviewed to determine the admission Glasgow Coma Scale (GCS) score, the extent of systemic injuries, the time to craniectomy, and the indications for craniectomy. Long-term functional outcome and independence levels were evaluated using the Glasgow Outcome Scale (GOS) and a Likert patient quality-of-life rating scale. Twenty-three craniectomies were performed in children during the study period. The mean patient age at craniectomy was 11.9 years (range 2-19 years). In all patients, the computed tomography scans obtained at presentation revealed pathological findings, with diffuse axonal injury and traumatic contusions being the most common abnormalities. The median presenting GCS score was 4.6 (range 3-9). Nineteen patients (83%) suffered from other systemic injuries. One patient (4%) died intraoperatively and six patients (26%) died postoperatively. Postoperative intracranial pressure (ICP) control was obtained in 19 patients (83%); an ICP greater than 20 mm Hg was found to have the strongest correlation with subsequent brain death (p = 0.001). The mean follow-up duration was 63 months (range 11-126 months, median 49 months). The mean GOS score at the 2-year follow-up examination was 4.2 (median 5). At the most recent follow-up examination, 13 (81%) of 16 survivors had returned to school and only three survivors (18%) were dependent on caregivers.

CONCLUSIONS

Although the mortality rate for children with severe TBI remains high, decompressive craniectomy is effective in reducing ICP and is associated with good outcomes in surviving patients.

Brain edema after intracerebral hemorrhage: mechanisms, treatment options, management strategies, and operative indications

Primary intracerebral hemorrhage (ICH) is associated with a high mortality rate and severe morbidity. The treatment of choice is still controversial, given that data from several clinical trials have not provided convincing evidence to support the efficacy of surgical clot removal. Favoring early clot removal is evidence that the limited release of specific neurotoxins associated with the breakdown products of hemoglobin underlies secondary brain injury. Attention has therefore shifted to perilesional brain injury, especially brain edema, as a potential target for therapeutic intervention in patients with ICH. In this review the authors address current understanding of the causes of edema formation following ICH and the treatment options, which are mostly supportive in nature.

Decompression craniectomy after traumatic brain injury: recent experimental results

Among the secondary events occurring after traumatic brain injury (TBI) pathologically increased intracranial pressure (ICP) correlates most closely with poor outcome. In addition to infusion of hypertonic solutions, e.g. mannitol, and other medical measures, decompression of the brain by surgical removal of a portion of the cranium (craniectomy) has been used for many decades as an intuitive strategy for the treatment of post-traumatic ICP increase. The lack of evidence-based clinical and controversial experimental data, however, resulted in decompressive craniectomy to be recommended by most national and international guidelines only as a third tier therapy for the treatment of pathologically elevated ICP. Ongoing clinical trials on the use of decompressive craniectomy after TBI may clarify many aspects of the clinical application of this technique, however, some important pathophysiological issues, e.g. the timing of decompression craniectomy, its effect on brain edema formation, and its role for secondary brain damage, are still widely discussed and can only be addressed in experimental settings. The aim of the current review was therefore to summarize and discuss recent experimental data dealing with the use of decompression craniectomy following TBI. The present results suggest that surgical decompression effectively prevents secondary brain damage when performed early enough. Although caution should be taken when transferring conclusions drawn from experimental settings to the clinical situation, the current literature suggests that the timing of decompression may be of utmost importance in order to exploit the full neuroprotective potential of craniectomy following TBI.

Decompressive craniectomy for the treatment of refractory high intracranial pressure in traumatic brain injury

BACKGROUND

High intracranial pressure (ICP) is the most frequent cause of death and disability after severe traumatic brain injury (TBI). High ICP is treated by general maneuvers (normothermia, sedation etc) and a set of first line therapeutic measures (moderate hypocapnia, mannitol etc). When these measures fail to control high ICP, second line therapies are started. Among these, second line therapies such as barbiturates, hyperventilation, moderate hypothermia or removal of a variable amount of skull bone (known as decompressive craniectomy) are used.

OBJECTIVES

To assess the effects of secondary decompressive craniectomy (DC) on outcome and quality of life in patients with severe TBI in whom conventional medical therapeutic measures have failed to control raised ICP.

SEARCH STRATEGY

We searched the Cochrane Injuries Group's Trial Register, CENTRAL, MEDLINE, EMBASE, Best Evidence, Clinical Practice Guidelines, PubMed, CINAHL, the National Research Register and Google Scholar. We also handsearched relevant conference proceedings and contacted experts in the field and the authors of included studies.

SELECTION CRITERIA

Randomized or quasi-randomized studies assessing patients over the age of 12 months with a severe TBI who underwent DC to control ICP refractory to conventional medical treatments.

DATA COLLECTION AND ANALYSIS

Two authors independently examined the electronic search results for reports of possibly relevant trials and for retrieval in full. One author applied the selection criteria, performed the data extraction and assessed methodological quality. Study authors were contacted for additional information.

MAIN RESULTS

We found one trial with 27 participants conducted in the pediatric population (>18 years). DC was associated with a risk ratio (RR) for death of 0.54 (95% CI 0.17 to 1.72), and RR of 0.54 for death, vegetative status or severe disability 6 to 12 months after injury (95% CI 0.29 to 1.07).

AUTHORS' CONCLUSIONS

There is no evidence to support the routine use of secondary DC to reduce unfavourable outcome in adults with severe TBI and refractory high ICP. In the pediatric population DC reduces the risk of death and unfavourable outcome. Despite the wide confidence intervals for death and the small sample size of the only study identified, this treatment maybe justified in patients below the age of 18 when maximal medical treatment has failed to control ICP. To date, there are no results from randomised trials to confirm or refute the effectiveness of DC in adults. However, the results of non-randomized trials and controlled trials with historical controls involving adults, suggest that DC may be a useful option when maximal medical treatment has failed to control ICP. There are two ongoing randomized controlled trials of DC (Rescue ICP and DECRAN) that may allow further conclusions on the efficacy of this procedure in adults.

Decompressive craniectomy in traumatic brain injury: outcome following protocol-driven therapy

Although decompressive craniectomy following traumatic brain injury is an option in patients with raised intracranial pressure (ICP) refractory to medical measures, its effect on clinical outcome remains unclear. The aim of this study was to evaluate the outcome of patients undergoing this procedure as part of protocol-driven therapy between 2000-2003. This was an observational study combining case note analysis and follow-up. Outcome was assessed at an interval of at least 6 months following injury using the Glasgow Outcome Scale (GOS) score and the SF-36 quality of life questionnaire. Forty-nine patients underwent decompressive craniectomy for raised and refractory ICP (41 [83.7%] bilateral craniectomy and 8 [16.3%] unilateral). Using the Glasgow Coma Scale (GCS), the presenting head injury grade was severe (GCS 3-8) in 40 (81.6%) patients, moderate (GCS 9-12) in 8 (16.3%) patients, and initially mild (GCS 13-15) in 1 (2.0%) patient. At follow-up, 30 (61.2%) patients had a favorable outcome (good recovery or moderate disability), 10 (20.48) remained severely disabled, and 9 (18.4%) died. No patients were left in a vegetative state. Overall the results demonstrated that decompressive craniectomy, when applied as part of protocol-driven therapy, yields a satisfactory rate of favorable outcome. Formal prospective randomized studies of decompressive craniectomy are now indicated.

Management of Increased Intracranial Pressure in the Critically Ill Child With an Acute Neurological Injury

Increased intracranial pressure reflects the presence of mass effect in the brain and is associated with a poor outcome in children with acute neurological injury. If sustained, it has a negative effect on cerebral blood flow and cerebral perfusion pressure, can cause direct compression of vital cerebral structures, and can lead to herniation. The management of the patient with increased intracranial pressure involves the maintenance of an adequate cerebral perfusion pressure, prevention of intracranial hypertension, and optimization of oxygen delivery. This article reviews the neurological assessment, pathophysiology, and management of increased intracranial pressure in the critically ill child who has sustained an acute neurological injury.

Hypertonic saline solutions in brain injury

PURPOSE OF REVIEW

Hypertonic saline solutions have received renewed attention as effective agents for the treatment of cerebral edema and in brain resuscitation in a variety of brain injury paradigms. Although evidence of the beneficial action of hypertonic saline solutions in traumatic brain injury is robust, data supporting use in other conditions are only now mounting.

RECENT FINDINGS

Osmotic properties of hypertonic saline solutions have been well studied in laboratory-based studies in animal models and in patients with acute brain injury. There are, in addition, emerging data on the extraosmotic actions on brain pathophysiology. This review cites baseline literature and provides new evidence of actions of hypertonic saline solutions: (a). in augmenting cerebral blood flow after subarachnoid hemorrhage, (b). as an antiinflammatory adjunct, and (c). utility in chemonucleolysis for intervertebral disc disease and treatment of seizures associated with severe hyponatremia.

SUMMARY

Brain injury from diverse etiologies including trauma, ischemic stroke, global cerebral ischemia from cardiac arrest, intraparenchymal or subarachnoid hemorrhage, infection, or toxic-metabolic derangements are commonly encountered in the clinical setting. Many of these conditions are associated with cerebral edema with or without elevated intracranial pressure. Osmotherapy constitutes the cornerstone of medical therapy for such patients. Hypertonic saline solutions have received renewed attention in clinical practice as osmotic agents for cerebral resuscitation. This article reviews experimental and clinical evidence of the efficacy of hypertonic saline solutions and elaborates on their use in patients with acute neurologic injury. Important areas for current and future research are highlighted before the use of hypertonic saline solutions can be accepted for widespread use.

Critical decision making in severe head injury management

The management of severe head injury (SHI) remains a major challenge not only for neurosurgeons but also for all other health professionals involved in the care of trauma patients. Any trauma patient with SHI is at risk of further neurological deterioration if appropriate measures are not instituted from the start of his or her treatment. Secondary insults due to ischaemic, hypotensive, and metabolic or other causes are still common, even in the most advanced neurocritical care settings. Management controversies are widespread and few decision options can be supported by Class I evidence. This article attempts to provide an up-to-date review of the published recommendations that could help health professionals in their management of SHI.