Intracranial pressure and surgical decompression for traumatic brain injury: biological rationale and protocol for a randomized clinical trial

Changes in Posttraumatic Brain Edema in Craniectomy-Selective Brain Hypothermia Model Are Associated With Modulation of Aquaporin-4 Level

Both hypothermia and decompressive craniectomy have been considered as a treatment for traumatic brain injury. In previous experiments we established a murine model of decompressive craniectomy and we presented attenuated edema formation due to focal brain cooling. Since edema development is regulated via function of water channel proteins, our hypothesis was that the effects of decompressive craniectomy and of hypothermia are associated with a change in aquaporin-4 (AQP4) concentration. Male CD-1 mice were assigned into following groups (n = 5): sham, decompressive craniectomy, trauma, trauma followed by decompressive craniectomy and trauma + decompressive craniectomy followed by focal hypothermia. After 24 h, magnetic resonance imaging with volumetric evaluation of edema and contusion were performed, followed by ELISA analysis of AQP4 concentration in brain homogenates. Additional histopathological analysis of AQP4 immunoreactivity has been performed at more remote time point of 28d. Correlation analysis revealed a relationship between AQP4 level and both volume of edema (r² = 0.45, p < 0.01, ^**) and contusion (r² = 0.41, p < 0.01, ^**) 24 h after injury. Aggregated analysis of AQP4 level (mean ± SEM) presented increased AQP4 concentration in animals subjected to trauma and decompressive craniectomy (52.1 ± 5.2 pg/mL, p = 0.01; ^*), but not to trauma, decompressive craniectomy and hypothermia (45.3 ± 3.6 pg/mL, p > 0.05; ns) as compared with animals subjected to decompressive craniectomy only (32.8 ± 2.4 pg/mL). However, semiquantitative histopathological analysis at remote time point revealed no significant difference in AQP4 immunoreactivity across the experimental groups. This suggests that AQP4 is involved in early stages of brain edema formation after surgical decompression. The protective effect of selective brain cooling may be related to change in AQP4 response after decompressive craniectomy. The therapeutic potential of this interaction should be further explored.

Elevated cell-free plasma DNA level as an independent predictor of mortality in patients with severe traumatic brain injury

Trauma is the leading cause of death in individuals less than 45 years old worldwide, and up to 50% of trauma fatalities are because of brain injury. Prediction of outcome is one of the major problems associated with severe traumatic brain injury (TBI), and research efforts have focused on the investigation of biomarkers with prognostic value after TBI. Therefore, our aim was to investigate whether cell-free DNA concentrations correlated to short-term primary outcome (survival or death) and Glasgow Coma Scale (GCS) scores after severe TBI. A total of 188 patients with severe TBI were enrolled in this prospective study; outcome variables comprised survival and neurological assessment using the GCS at intensive care unit (ICU) discharge. Control blood samples were obtained from 25 healthy volunteers. Peripheral venous blood was collected at admission to the ICU. Plasma DNA was measured using a real-time quantitative polymerase chain reaction (PCR) assay for the β-globin gene. There was correlation between higher DNA levels and both fatal outcome and lower hospital admission GCS scores. Plasma DNA concentrations at the chosen cutoff point (≥171,381 kilogenomes-equivalents/L) predicted mortality with a specificity of 90% and a sensitivity of 43%. Logistic regression analysis showed that elevated plasma DNA levels were independently associated with death (p<0.001). In conclusion, high cell-free DNA concentration was a predictor of short-term mortality after severe TBI.

Operative and nonoperative linguistic outcomes in brain injury patients

OBJECTIVE AND BACKGROUND

Linguistic function is one of vulnerable aspects of traumatic brain injury (TBI) which may have destructive effects on patients' communicative activities and daily life, years following trauma. This paper attempts to answer the controversy whether surgery affects increase and decrease of linguistic impairment or not.

MATERIALS AND METHODS

Two hundred forty-one TBI patients aged 18-65 with abnormal CT findings and at least 20 minute post-trauma amnesia (PTA), who were conscious at discharge, participated in this study. Based on operative intervention, the samples were divided into two groups: operative and nonoperative. Cognitive and aphasic deficits were inspected formally and pragmatic disorder was informally appraised at discharge.

RESULTS

The groups had no significant differences in aphasia incidence and language pragmatic impairment, though they were significantly distinctive in aphasia subcategories and cognitive deficit after trauma. Fluent aphasia was more common in both groups alike. In aphasia subcategories, however, transcortical sensory aphasia (TSA) in operative and anomia in nonoperative group were the most prevalent. Several variables appeared strikingly related to higher aphasia in operative groups as follows: moderate to severe injury, 18-35 and over 50 years of age, more than 1 week PTA, intracranial surgery of multiple lesions in left or bilateral hemisphere fronto-temporal cortex plus post-trauma cognitive and pragmatic impairments, and diffuse axonal injuries.

DISCUSSION

Almost certainly, meaningful drop of cognitive function post surgery roots back in significant loss of initial consciousness level. Related factors to postoperative aphasia suggest taking policies through surgery intervention. Discerning the indispensable contributions of neurosurgeons, neurolinguists, and neuroscientists, results inspire more clinical future studies.

Contralateral subdural effusion related to decompressive craniectomy performed in patients with severe traumatic brain injury

BACKGROUND

Contralateral subdural effusion caused by decompressive craniectomy (DC) is not uncommon. However, it has rarely been reported.

METHOD

From 2004 to 2008, 123 severe traumatic brain injury (TBI) patients were identified as having undergone DC for increased intracranial pressure (IICP) with or without removal of a blood clot or contused brain. Of these 123 patients, nine developed delayed contralateral subdural effusion. Demographics, clinical presentations, treatment and outcome were reported.

RESULTS

The overall incidence of contralateral subdural effusion was 7.3%. On average, this complication was found 23 days after DC. Of the nine patients, six had neurological deterioration and received drainage through a burr hole. One patient needed a subsequent subduro-peritoneal shunting because of recurrent subdural effusion.

CONCLUSION

Contralateral subdural effusions may be not uncommon and need more aggressive treatment because of their tendency to cause midline shift. Surgical intervention may be warranted if the patients develop deteriorating clinical manifestations or if the subdural effusion has an apparent mass effect.

Contralateral subdural effusion after decompressive craniectomy in patients with severe traumatic brain injury: clinical features and outcome

BACKGROUND

Contralateral subdural effusion (SDE) is usually considered as an uncommon complication after decompressive craniectomy (DC) for head trauma. This complication may need more aggressive treatment because of its tendency to cause midline shift and neurologic deterioration. In this article, we present our experience with this group of patients and discuss the diagnosis and management of this entity.

METHODS

This study included 13 patients with severe traumatic brain injury who developed contralateral SDE after DC. Clinical and radiographic information was obtained through a retrospective review of the medical records and the radiographs.

RESULTS

The average time from the procedure of DC to the diagnosis of contralateral SDE was 13 days. Deterioration of clinical condition or appearance of new symptoms/signs related to the contralateral SDE was noted in four patients. In the remaining nine patients without apparent clinical deterioration, the contralateral SDE was discovered on routine computed tomography scan. Six patients were treated conservatively and the contralateral SDE resolved gradually. In six patients who underwent burr hole craniectomy to evacuate the SDE, the operation had successfully drained the SDE in four patients. Two patients received subsequent subduroperitoneal shunt to manage the reaccumulation of SDE. In one patient, subduroperitoneal shunt and cranioplasty were performed simultaneously to treat the SDE. Subsequently, six patients (46.2%) developed hydrocephalus and underwent ventriculoperitoneal shunt operation.

CONCLUSIONS

Contralateral SDE may not be a rare complication after DC. Its diagnosis may be delayed or missed when it is asymptomatic or the clinical condition of the patient masks its clinical manifestations. It may be reasonable to repeat a computed tomography scan to detect contralateral SDE 2 weeks to 3 weeks after DC, irrespective of the clinical condition. In addition, posttraumatic hydrocephalus is a common late consequence in these patients. Close surveillance in these patients is indicated to prompt appropriate management.

Technical considerations in decompressive craniectomy in the treatment of traumatic brain injury

Refractory intracranial hypertension is a leading cause of poor neurological outcomes in patients with severe traumatic brain injury. Decompressive craniectomy has been used in the management of refractory intracranial hypertension for about a century, and is presently one of the most important methods for its control. However, there is still a lack of conclusive evidence for its efficacy in terms of patient outcome. In this article, we focus on the technical aspects of decompressive craniectomy and review different methods for this procedure. Moreover, we review technical improvements in large decompressive craniectomy, which is currently recommended by most authors and is aimed at increasing the decompressive effect, avoiding surgical complications, and facilitating subsequent management. At present, in the absence of prospective randomized controlled trials to prove the role of decompressive craniectomy in the treatment of traumatic brain injury, these technical improvements are valuable.

Comparison of the effect of decompressive craniectomy on different neurosurgical diseases

BACKGROUND

Many previous studies have reported that decompressive craniectomy has improved clinical outcomes in patients with intractable increased intracranial pressure (ICP) caused by various neurosurgical diseases. However there is no report that compares the effectiveness of the procedure in the different conditions. The authors performed decompressive craniectomy following a constant surgical indication and compared the clinical outcomes in different neurosurgical diseases.

MATERIALS AND METHODS

Seventy five patients who underwent decompressive craniectomy were analysed retrospectively. There were 28 with severe traumatic brain injury (TBI), 24 cases with massive intracerebral haemorrhage (ICH), and 23 cases with major infarction (MI). The surgical indications were GCS score less than 8 and/or a midline shift more than 6 mm on CT. The clinical outcomes were assessed on the basis of mortality and Glasgow Outcome Scale (GOS) scores. The changes of ventricular pressure related to the surgical intervention were also compared between the different disease groups.

FINDINGS

Clinical outcomes were evaluated 6 months after decompressive craniectomy. The mortality was 21.4% in patients with TBI, 25% in those with ICH and 60.9% in MI. A favourable outcome, i.e. GOS 4-5 (moderate disability or better) was observed in 16 (57.1%) patients with TBI, 12 (50%) with ICH and 7 (30.4%) with MI. The change of ventricular pressure after craniectomy and was 53.2 (reductions of 17.4%) and further reduced by 14.9% (with dural opening) and (24.8%) after returning to its recovery room, regardless of the diseases group.

CONCLUSIONS

According to the mortality and GOS scores, decompressive craniectomy with dural expansion was found to be more effective in patients with ICH or TBI than in the MI group. However, the ventricular pressure change during the decompressive craniectomy was similar in the different disease groups. The authors thought that decompressive craniectomy should be performed earlier for the major infarction patients.

Do long-term results justify decompressive craniectomy after severe traumatic brain injury?

OBJECT

A decompressive craniectomy can be a life-saving procedure to relieve critically increased intracranial pressure. The survival of a patient is important as well as the subsequent and long-term quality of life. In this paper the authors' goal was to investigate whether long-term clinical results justify the use of a decompressive craniectomy.

METHODS

Thirty-three patients (20 males and 13 females) with a mean age of 36.3 years (range 13-60 years) with severe traumatic brain injury (Grades III and IV) and subsequent massive brain swelling were examined. For postoperative assessment the Barthel Index was used. A surgical intervention was based on the following criteria: 1) The intracranial pressure could not be controlled by conservative treatment and constantly exceeded 30 mm Hg (cerebral perfusion pressure<50 mm Hg). 2) Transcranial Doppler ultrasonography revealed only a systolic flow pattern or systolic peaks. 3) There were no other major injuries. 4) The patient was not older than 60 years.

RESULTS

One-fifth of all patients died and one-fifth remained in a vegetative state. Mild deficits were seen in 6 of 33 patients. A full rehabilitation (Barthel Index 90-100) was achieved in 13 patients (39.4%). Five patients could resume their former occupation, and another 4 had to change jobs.

CONCLUSIONS

Age remains to be one of the most important exclusion factors. Decompressive craniectomy provided good clinical results in nearly 40% of patients who were otherwise most likely to die. Therefore, long-term results justify the use of decompressive craniectomy in this case series.

Cranioplasty of large cranial defect at an early stage after decompressive craniectomy performed for severe head trauma

Large cranial defects resulting from decompressive craniectomy performed for refractory intracranial hypertension after head trauma is one of the indications for cranioplasty, and this procedure is commonly performed 3 months after craniectomy. However, the large cranial defect would lead to the kinds of complications early during the phase of these patients' recovery, which would go against rehabilitation. This study retrospectively reviewed 23 patients undergoing early cranioplasty (5-8 weeks after craniectomy) in the last 4 years with a detailed choice of patients, outcome of complications after head trauma and large craniectomy, as well as assessment of prognosis. The early outcome (1 month later) revealed most of the patients who had conscious disturbance before the cranioplasty recovered their consciousness and presented an improved neurologic function. The long-dated prognosis (18 months later) revealed that 17 patients were good (independent patients) in this series (74%), whereas four patients survived with a severe disability (17%) and two remained in a vegetative state (9%). No dead patients or intracranial infection after the procedure were found in this study. Most patients' complications were relieved after the cranioplasty with improvements of symptoms or image of computed tomography scan. In conclusion, we consider that with the appropriate choice of patients and materials, early cranioplasty for large cranial defects after decompressive craniectomy would be safe and helpful for the improvement of patients' neurologic function and prognosis. To our knowledge, this series may be the first detailed report in English about early cranioplasty after decompressive craniectomy. We are going to perform prospective and retrospective contrastive studies to further confirm the effects of this procedure on the patients with large cranial defects after decompressive craniectomy.

Role of Plasma DNA as a Predictive Marker of Fatal Outcome following Severe Head Injury in Males

The prediction of outcome is one of the major problems associated with traumatic brain injury. Recently, investigations have been performed on the potential use of circulating cell-free DNA in plasma for clinical diagnosis and prognosis of a variety of conditions. In this study, we investigated DNA plasma concentrations after severe traumatic brain injury (TBI) and its correlation with primary outcome. We studied 41 male victims of TBI, with isolated severe TBI or severe TBI with associated exracranial injuries. Control samples were obtained from 13 healthy male volunteers. Plasma DNA was measured by a real-time PCR assay for the beta-globin gene. The mean time for first sampling (study entry) was 11.7 +/- 5.2 h after injury; subsequent DNA determinations were performed 24 h after study entry. Mean plasma DNA concentrations were significantly increased in TBI patients (366,485 and 131,708 kilogenomes-equivalents/L, at study entry and 24 h later, respectively) compared with the control group (3031 kilogenomes-equivalents/L). Additionally, a significant correlation between higher plasma DNA concentrations, determined 24 h after study entry, and fatal outcome was observed. However, at second sampling, there was no significant correlation between plasma DNA concentrations and the presence of associated extracranial injuries. High plasma DNA concentrations at second sampling time predicted fatal outcome with a sensitivity of 67% and specificity of 76%, considering a cut-off value of 77,883 kilogenomes-equivalents/L. Thus, this study showed that severe TBI is associated with elevated DNA plasma levels and suggests that persistent DNA elevations correlate with mortality.

Severe Traumatic Brain Injury in Austria V: CT findings and surgical management

OBJECTIVES

The aim of this paper is to describe CT findings and surgical management of patients with severe traumatic brain injury (TBI) in Austria.

PATIENTS AND METHODS

Data sets from 415 patients treated by 5 Austrian hospitals were available. The analysis focused on incidence, surgical management, and outcome of different types of intracranial lesions, and outcome of surgical interventions with and without monitoring of intracranial pressure (ICP). For the first analysis we assigned the patients to 16 groups based on the type of lesion as evaluated by CT scan. For the second analysis we created 4 groups based on surgical treatment (yes/no) and ICP monitoring (yes/no).

RESULTS

The mean age was 48.9 years with a male to female ratio of 299:116. The most frequent single lesions were contusions (CONT) and diffuse brain edema. Combined lesions were far more common than single lesions; the most frequently observed combinations included CONT and subarachnoid hemorrhage (SAH) with or without subdural hematoma (SDH). Surgery was done in 276 (66.5%) patients. Osteoplastic surgery (OPS; n = 221) was the most common method followed by osteoclastic surgery (OCS; n = 91) and decompressive craniectomy (DEC; n = 15). ICU mortality was 29.7% for all patients who had any kind of surgery, which was lower than that of patients who were treated non-operatively (33.1%). The ICU mortality of patients with SDH was lower with OCS (18.8%) than with OPS (36.0%). Patients who received ICP monitoring but did not require surgery had the lowest 90 day mortality (17.5%).

CONCLUSIONS

ICP monitoring seems to be beneficial in both operatively and non-operatively treated patients with severe TBI. Patients with SDH who were operated on had significantly better outcomes. In patients with SDH, their outcome after osteoclastic surgery was significantly better than after osteoplastic procedures.

Outcome after surgical decompression of severe traumatic brain injury

One of the factors that affects outcome following severe traumatic brain injury is development and progression of cerebral oedema with associated increase in intracranial pressure (ICP). Uncontrolled elevations of ICP may compromise energy metabolism of the injured brain and lead to secondary injury, affecting neurological outcome of the patient. Decompressive craniectomy has been used for over a century as a treatment of refractory brain swelling in a variety of neurological conditions. However, conclusive evidence of whether it has a beneficial or adverse affect on outcome is lacking. This article reviews the existing evidence on the role of decompressive craniectomy in management of patients with traumatic brain injury and stresses the need for randomised controlled trials.

Cerebral edema leading to decompressive craniectomy: an assessment of the preceding clinical and neuromonitoring trends

The aim of this study was to examine the pre-operative clinical and neuromonitoring courses in patients with a decompressive craniectomy to assess and to compare clinical and neuromonitoring signs indicating extensive cerebral edema. We conducted a retrospective analysis of the clinical signs and courses of simultaneous monitoring of intracranial pressure (ICP) and cerebral oxygenation (PtiO2) in 26 consecutive patients who were sedated and treated with a decompressive craniectomy due to extensive cerebral edema after aneurysmal subarachnoid hemorrhage (SAH) (n = 20) or severe head injury (SHI) (n = 6). Pathological monitoring trends always preceded clinical deterioration. In 18 of 26 patients extensive cerebral edema was indicated solely by increasing ICP > 20 mmHg or decreasing PtiO2 < 10 mmHg or both. Anisocoria occurred in only 8 of 26 patients. As opposed to SHI patients, 9 of 20 SAH patients showed decreasing PtiO2 as first warning sign clearly before neurological deterioration or ICP increase. This series shows the utility of combined ICP and PtiO2 monitoring in patients who develop extensive cerebral edema. Pathological monitoring trends indicate deterioration prior to clinical signs which offers a wider therapeutical window. PtiO2 monitoring appears to be particularly valuable after aneurysmal SAH as adjunct to ICP monitoring and CT imaging.

Role of serum S100B as an early predictor of high intracranial pressure and mortality in brain injury: a pilot study

OBJECTIVE

To investigate whether serum S100B is suitable as a sensitive biomarker for early prediction of increased intracranial pressure and mortality rates after brain injury.

DESIGN

A prospective, longitudinal study.

SETTING

Neurosurgical intensive care unit.

PATIENTS

Twenty-one patients with acute brain injury and 13 healthy controls.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We assessed Glasgow Coma Scale score and pupil reaction on admission and quantified serum S100B (in-house enzyme-linked immunosorbent assay) and intracranial pressure on admission and the subsequent 6 days. Serum S100B concentrations on admission and day 1 were significantly higher in patients with fatal outcome (p <.05, p<.01, respectively), with a sensitivity of 100% and a specificity of 75-83%. Patients with high serum S100B on admission had an eight-fold and on day 1 a 12-fold increased relative risk of a fatal outcome. Subsequent serum S100B values predicted the development of high intracranial pressure in patients with traumatic brain injury (p <.01). Patients with high intracranial pressure on day 5 had an 11-fold and on day 6 a nine-fold increased risk of fatal outcome.

CONCLUSIONS

Serum S100B is a sensitive biomarker for early prediction of the development of high intracranial pressure and fatal outcome following acute brain injury. Monitoring S100B concentrations could contribute to early detection of patients at risk of secondary increases in intracranial pressure and subsequent mortality. This would allow earlier targeting of therapy in selected patients.