Impact of traumatic subarachnoid hemorrhage on outcome in nonpenetrating head injury. Part II: Relationship to clinical course and outcome variables during acute hospitalization

Surgical Management of Trauma-Related Intracranial Hemorrhage-a Review

PURPOSE OF REVIEW

The surgical management of trauma-related intracranial hemorrhage is characterized by marked heterogeneity. Large prospective randomized trials have generally been prohibited by the ubiquity of concordant pathology, diversity of trauma systems, and paucity of clinical equipoise among providers.

RECENT FINDINGS

To date, the results of retrospective studies and surgeon preference have driven the indications, modality, extent, and timing of surgical intervention in the global neurosurgical community. With advances in our understanding of the pathophysiology of hemorrhagic TBI and the advent of novel surgical techniques, a reevaluation of surgical indication, timing, and approach is warranted. In this way, we can work to optimize surgical outcomes, achieving maximal functional recovery while minimizing surgical morbidity.

Role of computed tomography scores and findings to predict early death in patients with traumatic brain injury: A reappraisal in a major tertiary care hospital in Nepal

Background:

Glasgow Coma Scale has been a long sought model to classify patients with head injury. However, the major limitation of the score is its assessment in the patients who are either sedated or under the influence of drugs or intubated for airway protection. The rational approach for prognostication of such patients is the utility of scoring system based on the morphological criteria based on radiological imaging. Among the current armamentarium, a scoring system based on computed tomography (CT) imaging holds the greatest promise in conquering our conquest for the same.

Methods:

We included a total of 634 consecutive neurosurgical trauma patients in this series, who presented with mild-to-severe traumatic brain injury (TBI) from January 2013 to April 2014 at a tertiary care center in rural Nepal. All pertinent medical records (including all available imaging studies) were reviewed by the neurosurgical consultant and the radiologist on call. Patients’ worst CT image scores and their outcome at 30 days were assessed and recorded. We then assessed their independent performance in predicting the mortality and also tried to seek the individual variables that had significant interplay for determining the same.

Results:

Both imaging score (Marshall) and clinical score (Rotterdam) can be used to reliably predict mortality in patients with acute TBI with high prognostic accuracy. Other specific CT characteristics that can be used to predict early mortality are traumatic subarachnoid hemorrhage, midline shift, and status of the peri-mesencephalic cisterns.

Conclusion:

We demonstrated in this cohort that though the Marshall score has the high predictive power to determine the mortality, better discrimination could be sought through the application of the Rotterdam score that encompasses various individual CT parameters. We thereby recommend the use of such comprehensive prognostic model so as to augment our predictive power for properly dichotomizing the prognosis of the patients with TBI. In the future, it will therefore be important to develop prognostic models that are applicable for the majority of patients in the world they live in, and not just a privileged few who can use resources not necessarily representative of their societal environment.

A comparative study between Marshall and Rotterdam CT scores in predicting early deaths in patients with traumatic brain injury in a major tertiary care hospital in Nepal

PURPOSE

CT plays a crucial role in the early assessment of patients with traumatic brain injury (TBI). Marshall and Rotterdam are the mostly used scoring systems, in which CT findings are grouped differently. We sought to determine the values of the scoring system and initial CT findings in predicting the death at hospital discharge (early death) in patients with TBI.

METHODS

There were consecutive 634 traumatic neurosurgical patients with mild-to-severe TBI admitted to the emergency department of College of Medical Sciences. Their initial CT and status at hospital discharge (dead or alive) were reviewed, and both CT scores were calculated. We examined whether each score is related to early death; compared the two scoring systems' performance in predicting early death, and identified the CT findings that are independent predictors for early death.

RESULTS

Both imaging score (Marshall) and clinical score (Rotterdam) can be used to reliably predict mortality in patients with acute traumatic brain injury with high prognostic accuracy. Other specific CT characteristics that can be used to predict early mortality are traumatic subarachnoid hemorrhage, midline shift and status of the peri-mesencephalic cisterns.

CONCLUSIONS

Marshall CT classification has strong predictive power, but greater discrimination can be obtained if the individual CT parameters underlying the CT classification are included in a prognostic model as in Rotterdam score. Consequently, for prognostic purposes, we recommend the use of individual characteristics rather than the CT classification. Performance of CT models for predicting outcome in TBI can be significantly improved by including more details of variables and by adding other variables to the models.

Subarachnoid hemorrhage prevalence and its association with short-term outcome in pediatric severe traumatic brain injury

BACKGROUND

Subarachnoid hemorrhage (SAH) is an independent prognostic indicator of outcome in adult severe traumatic brain injury (sTBI). There is a paucity of investigations on SAH in pediatric sTBI. The goal of this study was to determine in pediatric sTBI patients SAH prevalence, associated factors, and its relationship to short-term outcome.

METHODS

We retrospectively analyzed 171 sTBI patients (pre-sedation GCS ≤8 and head MAIS ≥4) who underwent CT head imaging within the first 24 h of hospital admission. Data were analyzed with both univariate and multivariate techniques.

RESULTS

SAH was found in 42 % of sTBI patients (n = 71/171), and it was more frequently associated with skull fractures, cerebral edema, diffuse axonal injury, contusion, and intraventricular hemorrhage (p < 0.05). Patients with SAH had higher Injury Severity Scores (p = 0.032) and a greater frequency of fixed pupil(s) on admission (p = 0.001). There were no significant differences in etiologies between sTBI patients with and without SAH. Worse disposition occurred in sTBI patients with SAH, including increased mortality (p = 0.009), increased episodes of central diabetes insipidus (p = 0.002), greater infection rates (p = 0.002), and fewer ventilator-free days (p = 0.001). In sTBI survivors, SAH was associated with increased lengths of stay (p < 0.001) and a higher level of care required on discharge (p = 0.004). Despite evidence that SAH is linked to poorer outcomes on univariate analyses, multivariate analysis failed to demonstrate an independent association between SAH and mortality (p = 0.969).

CONCLUSION

SAH was present in almost half of pediatric sTBI patients, and it was indicative of TBI severity and a higher level of care on discharge. SAH in pediatric patients was not independently associated with increased risk of mortality.

Traumatic subarachnoid hemorrhage: our current understanding and its evolution over the past half century

Traumatic brain injury (TBI) is a common cause of morbidity and mortality in the US, especially among the young. Primary injury in TBI is preventable, whereas secondary injury is treatable. As a result, considerable research efforts have been focused on elucidating the pathophysiology of secondary injury and determining various prognosticators in the hopes of improving final outcome by minimizing secondary injury. One such variable, traumatic subarachnoid hemorrhage (tSAH), has been the focus of many discussions over the past half century as numerous clinical studies have shown tSAH to be associated with adverse outcome. Whether the relationship of tSAH with poorer outcome in TBI is merely an epiphenomenon or a result of direct cause and effect is unclear. Some investigators believe that tSAH is merely a marker of severer TBI, while others argue that it directly causes deleterious effects such as vasospasm and ischemia. At the present time, no proven treatment regimen aimed specifically at decreasing the detrimental effects of tSAH exists, although calcium channel blockers traditionally thought to target vasospasm have shown some promises. Given that tSAH may primarily be an early indicator of associated and evolving brain injury, vigilant diagnostic surveillance including serial head CT and prevention of secondary brain damage owing to hypotension, hypoxia and intracranial hypertension may be more cost-effective than attempting to treat potential adverse sequelae associated with tSAH.

Are initial radiographic and clinical scales associated with subsequent intracranial pressure and brain oxygen levels after severe traumatic brain injury?

BACKGROUND

Prediction of clinical course and outcome after severe traumatic brain injury (TBI) is important.

OBJECTIVE

To examine whether clinical scales (Glasgow Coma Scale [GCS], Injury Severity Score [ISS], and Acute Physiology and Chronic Health Evaluation II [APACHE II]) or radiographic scales based on admission computed tomography (Marshall and Rotterdam) were associated with intensive care unit (ICU) physiology (intracranial pressure [ICP], brain tissue oxygen tension [PbtO2]), and clinical outcome after severe TBI.

METHODS

One hundred one patients (median age, 41.0 years; interquartile range [26-55]) with severe TBI who had ICP and PbtO2 monitoring were identified. The relationship between admission GCS, ISS, APACHE II, Marshall and Rotterdam scores and ICP, PbtO2, and outcome was examined by using mixed-effects models and logistic regression.

RESULTS

Median (25%-75% interquartile range) admission GCS and APACHE II without GCS scores were 3.0 (3-7) and 11.0 (8-13), respectively. Marshall and Rotterdam scores were 3.0 (3-5) and 4.0 (4-5). Mean ICP and PbtO2 during the patients' ICU course were 15.5 ± 10.7 mm Hg and 29.9 ± 10.8 mm Hg, respectively. Three-month mortality was 37.6%. Admission GCS was not associated with mortality. APACHE II (P = .003), APACHE-non-GCS (P = .004), Marshall (P < .001), and Rotterdam scores (P < .001) were associated with mortality. No relationship between GCS, ISS, Marshall, or Rotterdam scores and subsequent ICP or PbtO2 was observed. The APACHE II score was inversely associated with median PbtO2 (P = .03) and minimum PbtO2 (P = .008) and had a stronger correlation with amount of time of reduced PbtO2.

CONCLUSION

Following severe TBI, factors associated with outcome may not always predict a patient's ICU course and, in particular, intracranial physiology.

Maximum thickness of subarachnoid blood is associated with mortality in patients with traumatic subarachnoid haemorrhage

This study was designed to evaluate whether the maximum thickness of subarachnoid blood is an independent prognostic marker of mortality after traumatic subarachnoid haemorrhage. Multivariate analysis showed the maximum thickness of subarachnoid blood was an independent predictor of death versus survival 1 month after injury and was inversely associated with Glasgow Coma Scale (GCS) score. Receiver operating characteristic curve analysis showed that maximum thickness of subarachnoid blood > 6.7 mm immediately after non-surgical resuscitation predicted 1-month mortality with 83.9% sensitivity and 67.1% specificity; its predictive value was similar to that of the GCS score. Addition of maximum thickness of subarachnoid blood to the GCS score did not significantly improve predictive performance. Hence, the maximum thickness of subarachnoid blood is a new independent prognostic marker of mortality and might become an additional, valuable tool for risk stratification and decision making in the acute phase of traumatic subarachnoid haemorrhage.

Neurological outcome in patients with traumatic brain injury and its relationship with computed tomography patterns of traumatic subarachnoid hemorrhage

Object

Traumatic subarachnoid hemorrhage (SAH) is a poor prognostic factor for traumatic brain injury. The authors aimed to further investigate neurological outcome among head injury patients by examining the prognostic values of CT patterns of traumatic SAH, in particular, the thickness and distribution.

Methods

The study was conducted using a database in a regional trauma center in Hong Kong. Data had been prospectively collected in consecutive trauma patients between January 2006 and December 2008. Patients included in the study had significant head injury (as defined by a head Abbreviated Injury Scale [AIS] score of 2 or more) with traumatic SAH according to admission CT.

Results

Over the 36-month period, 661 patients with significant head injury were admitted to the Prince of Wales Hospital in Hong Kong. Two hundred fourteen patients (32%) had traumatic SAH on admission CT. The mortality rate was significantly greater and a 6-month unfavorable outcome was significantly more frequent in patients with traumatic SAH. Multivariate analysis showed that the maximum thickness (mm) of traumatic SAH was independently associated with neurological outcome (OR 0.8, 95% CI 0.7–0.9) and death (OR 1.3, 95% CI 1.2–1.5) but not with the extent or location of hemorrhage.

Conclusions

Maximum thickness of traumatic SAH was a strong independent prognostic factor for death and clinical outcome. Anatomical distribution per se did not affect clinical outcome.

Interobserver variability in the assessment of CT imaging features of traumatic brain injury

The goal of our study was to determine the interobserver variability between observers with different backgrounds and experience when interpreting computed tomography (CT) imaging features of traumatic brain injury (TBI). We retrospectively identified a consecutive series of 50 adult patients admitted at our institution with a suspicion of TBI, and displaying a Glasgow Coma Scale score < or =12. Noncontrast CT (NCT) studies were anonymized and sent to five reviewers with different backgrounds and levels of experience, who independently reviewed each NCT scan. Each reviewer assessed multiple CT imaging features of TBI and assigned every NCT scan a Marshall and a Rotterdam grading score. The interobserver agreement and coefficient of variation were calculated for individual CT imaging features of TBI as well as for the two scores. Our results indicated that the imaging review by both neuroradiologists and neurosurgeons were consistent with each other. The kappa coefficient of agreement for all CT characteristics showed no significant difference in interpretation between the neurosurgeons and neuroradiologists. The average Bland and Altman coefficients of variation for the Marshall and Rotterdam classification systems were 12.7% and 21.9%, respectively, which indicates acceptable agreement among all five reviewers. In conclusion, there is good interobserver reproducibility between neuroradiologists and neurosurgeons in the interpretation of CT imaging features of TBI and calculation of Marshall and Rotterdam scores.

Classification and prediction of outcome in traumatic brain injury based on computed tomographic imaging

Traumatic brain injury (TBI) is a common and potentially devastating problem. The classification of TBI is necessary for accurate diagnosis and the prediction of outcomes. The increased use of early sedation, intubation and ventilation in more severely injured patients has decreased the value of the Glasgow Coma Scale for the purposes of classification. An alternative is the classification of TBI according to morphological criteria based on computed tomography (CT) investigations. This article reviews the current classification and prediction of outcomes in TBI based on CT imaging. Classifications based on the presence or absence of intracranial local lesions, diffuse injury, signs of subarachnoid or intra-ventricular haemorrhage and fractures or foreign bodies are considered, and their predictive value is discussed. Future studies should address the complicated issue of how optimally to combine CT characteristics for prognostic purposes and how to improve on currently used CT classifications to predict outcomes more accurately.

The role of early follow-up computed tomography imaging in the management of traumatic brain injury patients with intracranial hemorrhage

BACKGROUND

The purpose of this study was to investigate whether routine follow-up computed tomography (CT) for patients with head injury, in the absence of clinical indications, alters patient management.

METHODS

Nonpenetrating head injury patients admitted to San Francisco General Hospital during an 18-month period were reviewed. Patients not surgically treated at presentation and with a routine follow-up head CT within 24 hours were included. Surgical and nonsurgical interventions after repeat CT were assessed. Clinical and imaging parameters were correlated with progressive hemorrhagic injury (PHI) and with delayed development of surgical lesions.

RESULTS

PHI was identified in 49 (42%) of 116 patients. None of these patients required a nonoperative intervention in response to the PHI. Six of these patients developed a neurologic change concurrent with routine follow-up imaging and required operative intervention. Thus, no patient underwent an intervention in response to a worsening head CT in the absence of clinical findings. Of the six patients who developed a surgical lesion, two had increased intracranial pressure, one had a change in pupillary examination, three had worsening mental status, and one had change in the motor examination. Univariate risk factors for development of a delayed surgical lesion included 5 to 10 mm of midline shift (p = 0.001), basal cistern effacement (p = 0.01), and higher Marshall score (p = 0.01) on initial CT imaging.

CONCLUSIONS

Although PHI is common with head injury, delayed interventions in the absence of clinical indicators are uncommon. Our data suggest that early follow-up CT imaging in the setting of head trauma is not routinely indicated. We suggest that assessment, based on the severity of findings on initial brain imaging and serial clinical examinations, should guide the need for follow-up imaging in the setting of head trauma.

Prognostic value of computerized tomography scan characteristics in traumatic brain injury: results from the IMPACT study

Computerized tomography (CT) scanning provides an objective assessment of the structural damage to the brain following traumatic brain injury (TBI). We aimed to describe and quantify the relationship between CT characteristics and 6-month outcome, assessed by the Glasgow Outcome Scale (GOS). Individual patient data from the IMPACT database were available on CT classification (N = 5209), status of basal cisterns ( N = 3861), shift ( N = 4698), traumatic subarachnoid hemorrhage (tSAH) ( N = 7407), and intracranial lesions ( N = 7613). We used binary logistic and proportional odds regression for prognostic analyses. The CT classification was strongly related to outcome, with worst outcome for patients with diffuse injuries in CT class III (swelling; OR 2.50; CI 2.09-3.0) or CT class IV (shift; OR 3.03; CI 2.12-4.35). The prognosis in patients with mass lesions was better for patients with an epidural hematoma (OR 0.64; CI 0.56-0.72) and poorer for an acute subdural hematoma (OR 2.14; CI 1.87-2.45). Partial obliteration of the basal cisterns (OR 2.45; CI 1.88-3.20), tSAH (OR 2.64; CI 2.42-2.89), or midline shift (1-5 mm-OR 1.36; CI 1.09-1.68); >5 mm-OR 2.20; CI 1.64-2.96) were strongly related to poorer outcome. Discrepancies were found between the scoring of basal cisterns/shift and the CT classification, indicating observer variation. These were less marked in studies that had used a central review process. Multivariable analysis indicated that individual CT characteristics added substantially to the prognostic value of the CT classification alone. We conclude that both the CT classification and individual CT characteristics are important predictors of outcome in TBI. For clinical trials, a central review process is advocated to minimize observer variability in CT assessment.

Neurologic aspects of traumatic brain injury

Traumatic brain injury is a common neurologic condition that can have a significant emotional and financial burden. Neurologic injury is classified on the basis of initial clinical status by the Glasgow Coma Scale, and also by the type and location of head injury. Complications in the management of these patients are reviewed, ranging from intracranial pressure management and stroke to post-traumatic epilepsy. In addition, predictive prognostic variables that can be used to predict outcome based on a patient's presentation at the time of a head trauma are discussed. Finally, interventions such as induced hypothermia that can be undertaken to try to optimize outcome, are discussed along with current data in support of or against such techniques.

Subarachnoid hemorrhage induces dynamic changes in regional cerebral metabolism in rats

Following a subarachnoid hemorrhage (SAH), adult rats exhibit dynamic regional changes in cerebral glucose metabolism characterized by an increase in metabolic rates and a subsequent upregulation of cytochrome oxidase (CO). We evaluated both local cerebral metabolic rates for glucose (ICMRglc: (mol/100 g/min) and CO in 23 brain regions of interest (ROI). Sham animals underwent anesthesia and superficial surgery; saline-controls received an injection of 0.9% saline into the cisterna magna; and SAH rats received an injection of autologous blood into the cisterna magna. This blood, measured by albumin labeled with radioactive carbon 14, distributed throughout the brain but predominated ventrally. After experimental animals were sacrificed at day 0 (3 h), 1, 3, and 7 days postinjection, ROI were analyzed using [14C]2-deoxy-D-glucose autoradiography and CO histochemistry. ICMRglc in SAH rats increased in many regions (ranging from 0.7% to 32.2% above sham levels). Cytochrome oxidase also increased from 1% to 9% above sham levels, peaking on day 3. Conversely, saline-controls exhibited prolonged depression of ICMRglc (ranging from 11% to 35% below sham levels) and CO (ranging from 4% to 11% below sham levels) from day 0 through day 7. All saline-control ROI for all time points showed this metabolic depression, and between 91% and 95% of saline-control ROI presented lower CO levels as compared to sham. Overall, ICMRglc and CO levels were greater in SAH than in saline-control ROI. However, when considering the influence of subarachnoid blood on metabolic changes in SAH animals, both CO and 2DG levels did not correlate well with the amount of 14C-albumin binding. While previous studies have measured both metabolic rates of glucose and CO soon after SAH, this is the first to simultaneously conduct these measurements in the same SAH rat model.

Traumatic subarachnoid haemorrhage

The presence of subarachnoid blood following head injury is a significant risk factor for poor outcome. Treatment aims to prevent and treat secondary hypoxia, hypotension, intracranial haematoma, epilepsy and infection. There is good evidence for the benefit of nimodipine in aneurysmal subarachnoid haemorrhage. Its role in preventing cerebral ischaemia following trauma is currently under investigation.