Current reporting of responsiveness in acute cerebral disorders. A survey of the neurosurgical literature

The Estimated Verbal GCS Subscore in Intubated Traumatic Brain Injury Patients: Is it Really Better?

The Glasgow Coma Scale (GCS) has limited utility in intubated patients due to the inability to assign verbal subscores. The verbal subscore can be derived from the eye and motor subscores using a mathematical model, but the advantage of this method and its use in outcome prognostication in traumatic brain injury (TBI) patients remains unknown. We compared the validated "Core+CT"-IMPACT-model performance in 251 intubated TBI patients prospectively enrolled in the longitudinal OPTIMISM study between November 2009 and May 2015 when substituting the original motor GCS (mGCS) with the total estimated GCS (teGCS; with estimated verbal subscore). We hypothesized that model performance would improve with teGCS. Glasgow Outcome Scale (GOS) scores were assessed at 3 and 12 months by trained interviewers. In the complete case analysis, there was no statistically or clinically significant difference in the discrimination (C-statistic) at either time-point using the mGCS versus the teGCS (3 months: 0.893 vs. 0.871;12 months: 0.926 vs. 0.92). At 3 months, IMPACT-model calibration was excellent with mGCS and teGCS (Hosmer-Lemeshow "goodness-of-fit" chi square p value 0.9293 and 0.9934, respectively); it was adequate at 12 months with teGCS (0.5893) but low with mGCS (0.0158), possibly related to diminished power at 12 months. At both time-points, motor GCS contributed more to the variability of outcome (Nagelkerke ΔR²) than teGCS (3 months: 5.8% vs. 0.4%; 12 months: 5% vs. 2.6%). The sensitivity analysis with imputed missing outcomes yielded similar results, with improved calibration for both GCS variants. In our cohort of intubated TBI patients, there was no statistically or clinically meaningful improvement in the IMPACT-model performance by substituting the original mGCS with teGCS.

Clinical monitoring scales in acute brain injury: assessment of coma, pain, agitation, and delirium

Serial clinical examination represents the most fundamental and basic form of neurological monitoring, and is often the first and only form of such monitoring in patients. Even in patients subjected to physiological monitoring using a range of technologies, the clinical examination remains an essential tool to follow neurological progress. Key aspects of the clinical examination have now been systematized into scoring schemes, and address consciousness, pain, agitation, and delirium (PAD). The Glasgow Coma Scale has been the traditional tool to measure consciousness, but the full outline of unresponsiveness (FOUR) score has recently been validated in a variety of settings, and at present, both represent clinically useful tools. Assessment of PAD in neurologically compromised patients present special challenges. For pain, the Numeric Rating Scale is the preferred initial approach, with either the Behavioral Pain Scale or the Critical Care Pain Observation Tool in subjects who are not able to respond. The Nociception Coma Scale-Revised may be useful in patients with severe disorders of consciousness. Conventional sedation scoring tools for critical care, such as the Richmond Area Sedation Scale (RASS) and Sedation-Agitation Scale (SAS) may provide reasonable tools in some neurocritical care patients. The use of sedative drugs and neuromuscular blockers may invalidate the use of some clinical examination tools in others. The use of sedation interruption to assess neurological status can result in physiological derangement in unstable patients (such as those with uncontrolled intracranial hypertension), and is not recommended.

Swirl sign in intracerebral haemorrhage: definition, prevalence, reliability and prognostic value

Background

Swirl sign has previously been described in epidural hematomas as areas of low attenuation, radiolucency or irregular density. The aims of this study were to describe swirl sign in ICH, study its prevalence, study the reliability of the subjective evaluation on computed tomography (CT), and to explore its prognostic value.

Methods

CTs of 203 patients with ICH were retrospectively evaluated for the presence of swirl sign. Association between swirl sign and different clinical and radiological variables was studied.

Results

Inter- and intraobserver agreement with regard to the occurrence of swirl sign was substantial (К 0.80) and almost perfect (К 0.87), respectively. Swirl sign was found in 30% of the study population. 61% of patients with swirl sign were dead at one month compared with 21% of those with no swirl sign (p < 0.001). Only 19% of patients with swirl sign exhibited favorable outcome at three months compared with 53% of those with no swirl sign (p < 0.001). Patients with swirl sign exhibited larger ICHs with average ICH-volume 52 ± 50 ml (median 42 ml) compared with 15 ± 25 ml (median 6) in patients whose CT did not show swirl sign (p < 0.001). Swirl sign was independent predictor of death at one month (p = 0.03; adjusted odds ratio 2.6, 95% CI 1.1 – 6), and functional outcome at three months (p = 0.045; adjusted odds ratio 2.6, 95% CI 1.02 – 6.5).

Conclusions

As swirl sign showed to be an ominous sign, we recommend identification of this sign in cases of ICHs.

Hyperdense middle cerebral artery sign is an ominous prognostic marker despite optimal workflow

OBJECTIVES

To evaluate the association between the hyperdense middle cerebral artery sign (HMCAS) and the functional outcome on one hand, and different predictors such as the National Institutes of Health Stroke Scale (NIHSS), infarct size, ASPECTS Score, intracerebral hemorrhage, and mortality on the other hand.

MATERIAL AND METHODS

Retrospective analysis of 120 patients with MCA-stroke treated with intravenous thrombolysis. We tested the association between HMCAS and NIHSS, infarct volume, ASPECTS, outcome, level of consciousness, different recorded time intervals, and the day/time of admission.

RESULTS

Seventy-four percentage of patients treated with thrombolysis developed cerebral infarction. All patients with HMCAS (n = 39) sustained infarction and only 31% showed favorable outcome compared with 62% and 60%, respectively among patients without HMCAS (P < 0.001 and P = 0.002). There was statistically significant association between functional outcome and HMCAS (P = 0.002), infarct volume, NIHSS, and ASPECTS (P < 0.001). The time to treatment was 12 min shorter in patients who developed infarction (P = 0.037). Independent predictors for outcome were NIHSS and the occurrence of cerebral infarction on computed tomography for the whole study population, and infarct volume for patients who sustained cerebral infarction.

CONCLUSIONS

Despite optimal workflow, patients with HMCAS showed poor outcome after intravenous thrombolysis. The results emphasize the urgent need for more effective revascularization therapies and neuroprotective treatment in this subgroup of stroke patients.

Endorsement of the FOUR score for consciousness assessment in neurosurgical patients

The Full Outline of UnResponsiveness (FOUR) score was previously developed for neurological assessment, but has not been validated in neurosurgical patients, so was compared to the Glasgow Coma Scale (GCS) in practice. Four groups of raters, expert clinicians, novice clinicians, experienced nurses, and inexperienced nurses, assessed 64 patients in awake, drowsy, stuporous, and comatose conditions to investigate rater reliability. Then, 36 patients were evaluated by 1 expert clinician and 1 from the other groups randomly to test the difference. Spearman's correlation was used to find the correlation between both scores from 68 patients. The estimation of FOUR score cut points was validated by weighted kappa compared with the GCS to establish the risk prognosis. Score feasibility was analyzed by nonparametric test. Intraclass correlation in each group was over 0.9, with no difference between expert and inexperienced raters (p > 0.05). The correlation was 0.78. Low, intermediate, and high risk prognosis were associated with 0-7, 8-14, and 15-16 FOUR scores with kappa of 0.92. The feasibility of the FOUR score was lower than that of the GCS (p < 0.01). The FOUR score is reliable and valid for consciousness evaluation with some consequences for practicability. Extensive implementation would increase familiarity.

Coma

Coma is a state of unarousable unconsciousness due to dysfunction of the brain's ascending reticular activating system (ARAS), which is responsible for arousal and the maintenance of wakefulness. Anatomically and physiologically the ARAS has a redundancy of pathways and neurotransmitters; this may explain why coma is usually transient (seldom lasting more than 3 weeks). Emergence from coma is succeeded by outcomes ranging from the vegetative state to complete recovery, depending on the severity of damage to the cerebral cortex, the thalamus, and their integrated function. The clinical and laboratory assessments of the comatose patient are reviewed here, along with an analysis of how various conditions (structural brain lesions, metabolic and toxic disorders, trauma, infections, seizures, hypothermia, and hyperthermia) produce coma. Management issues include the determination of the cause and reversibility (prognosis) of neurological impairment, support of the patient, definitive treatment when possible, and the ethical considerations for those situations where marked disability is predicted with certainty.

Paediatric coma scales

Traumatic and non-traumatic coma is a common problem in paediatric practice with high mortality and morbidity. Early recognition of the potential for catastrophic deterioration in a variety of settings is essential and several coma scales have been developed for recording depth of consciousness that are widely used in clinical practice in adults and children. Prediction of outcome is probably less important, as this may be able to be modified by appropriate emergency treatment, and other clinical and neurophysiological criteria allow a greater degree of precision. The scales should be reliable, i.e. with little variation between observers and in test-retest by one observer, since this promotes confidence in the assessments at different time points and by different examiners. This is particularly important when the patient is being assessed by personnel dealing with adults as well as children, discussed on the telephone, handed over at shift change, or transferred between units or hospitals. The British Paediatric Neurology Association has recommended one of the modified child's Glasgow coma scales (CGCS) for use in the UK. This review looks at the recent history of the development of coma scales and the rationale for recommending the CGCS.

Petite histoire et quelques réflexions à propos des échelles de grades des hémorragies sous-arachnoïdiennes d’origine anévrismale et des échelles de suivi

A brief history of the most current scales of aneurysmal subarachnoid hemorrhage and follow-up is presented. Advantages and inaccuracies of these scales are discussed. The World Federation of Neurological Surgeons (WFNS) classification is recommended as the most objective and reliable although some critics exist about its use in particular conditions. The grading of the follow-up is also analyzed. Here, the Glasgow Outcome Scale (GOS) is the most common employed and promoted in a first approach in spite of its briefness. Secondary functional and neuropsychological examination at 6 or 12 months is to be recommended to enable a more accurate evaluation. In conclusion, the WFNS scales for subarachnoid hemorrhage and follow-up is proposed as the best way to allow comparison between work of different centers.

Diffusion-weighted MR imaging in closed head injury: high correlation with initial glasgow coma scale score and score on modified Rankin scale at discharge

PURPOSE

To determine whether diffusion-weighted magnetic resonance (MR) imaging findings and conventional MR imaging findings correlate with initial Glasgow Coma Scale score and score on modified Rankin scale at discharge.

MATERIALS AND METHODS

Twenty-six patients (18 male and eight female patients; mean age, 25.2 years; age range, 4-72 years) with diffuse axonal injury were examined with diffusion-weighted MR imaging and with fluid-attenuated inversion recovery, T2-weighted fast spin-echo, and T2*-weighted gradient-echo sequences. All images were evaluated by two neuroradiologists in consensus. Tissue volume with trauma-related signal-intensity abnormality on images from each sequence, number of lesions for each sequence, number of lesions for all sequences, and number of lesions with reduced apparent diffusion coefficient were correlated with scores on Glasgow Coma Scale and modified Rankin scale. Involvement of brainstem, deep gray matter, and corpus callosum were also correlated with clinical scores. Spearman rank correlation coefficients (r) were calculated.

RESULTS

The strongest correlation was between signal-intensity abnormality volume on diffusion-weighted images and modified Rankin score (r = 0.772, P <.001). The strength of this correlation did not improve when only volume of lesions with decreased apparent diffusion coefficient was considered. For lesion number, the strongest correlation was between lesion number on images acquired with all sequences and modified Rankin score (r = 0.662, P <.001). For lesion location, the strongest correlation was between lesion location in the corpus callosum and modified Rankin score (r = 0.513, P =.007).

CONCLUSION

Volume of lesions on diffusion-weighted MR images provides the strongest correlation with a score of subacute on modified Rankin scale at discharge. Total lesion number also correlates well with modified Rankin score. In future, diffusion-weighted images may be useful in determining treatment strategies for acute head injury.

The use of bispectral index to monitor unconscious children

The use of the Glasgow Coma Scale may be limited by the experience of physicians, errors resulting from subjectivity, the inability of patients to respond, and discontinuity. This study demonstrates that the Bispectral Index scores correlate well with scores from the Glasgow Coma Scale and that Bispectral Index scores can provide real-time, objective, and continuous monitoring of the consciousness level of critically ill children. Sixteen patients with consciousness disturbance, who were admitted to a pediatric intensive care unit of a tertiary university-affiliated children's hospital, were enrolled in this study. The patients received 34 Glasgow Coma Scale assessments and Bispectral Index scores. The age of patients ranged from 10 to 192 months (mean +/- S.E. = 68.4 +/- 12.3 months). Glasgow Coma Scale ranged from 3 to 11 (mean +/- S.E. = 6.3 +/- 0.4), and Bispectral Index score ranged from 0 to 100 (mean +/- S.E. = 55.4 +/- 5.6). A positive correlation was found to exist between Glasgow Coma Scale and Bispectral Index score (r = 0.76, P < 0.001). In conclusion, the Bispectral Index score correlates well with the Glasgow Coma Scale in critically ill children who score between 3 and 11 on the Glasgow Coma Scale.

Comparison of the Glasgow Coma Scale and the Reaction Level Scale for assessment of cerebral responsiveness in the critically ill

OBJECTIVE

The Glasgow Coma Scale (GCS) is a well-known source of error in outcome prediction models. We compared assessment of cerebral responsiveness with the GCS and the Reaction Level Scale (RLS) in two otherwise similar outcome prediction models.

DESIGN AND SETTING

Prospective, observational study in a general intensive care unit.

PATIENTS AND PARTICIPANTS

All admissions of patients with or at risk of developing impaired brain function between 1997 and 1998 ( n=534).

MEASUREMENTS AND RESULTS

Admissions were scored by RLS and APACHE II (includes scoring with the GCS). The RLS scores were transformed to APACHE II central nervous system scores according to a predetermined protocol. APACHE II estimated probability of death was calculated conventionally with the GCS and the RLS. Vital status 90 days after admission was secured from a national database. Bias and precision was 0.5% and 16.6%, respectively. The area under receiver operating characteristic curves was slightly but significantly greater with the RLS-based APACHE II model than with the GCS-based model (0.92 vs. 0.90). Discrimination was improved primarily in admissions with low and intermediate probability of death.

CONCLUSIONS

Scoring of cerebral responsiveness with the RLS instead of the GCS was associated with minimal bias of the APACHE II probability of death estimate. Assessment of consciousness in critically ill with the RLS deserves further evaluation

The use of head computed tomography in elderly patients sustaining minor head trauma

The study objectives were to ascertain historical and clinical criteria differentiating intracranial injury (ICI) in elderly patients with minor head trauma (MHT), and determine applicability of current head computed tomography (CT) scan indications in this population. A 12-month retrospective chart review was performed at a community teaching hospital with 34,000 annual Emergency Department (ED) visits. Included were patients > or = 65 years old sustaining MHT with a Glasgow Coma Scale (GCS) score of 13-15 who had a CT scan performed during their hospital stay. Data included: injury mechanism, symptoms, signs, GCS, anticoagulation use or studies, presence of alcohol or drug, CT scan result, diagnosis, and outcome and intervention(s). There were 133 patients, with 19 (14.3%) suffering ICI. Four ICI patients required neurosurgical intervention. The mean age was 80.4 years and 66% were female. Four of 19 ICI patients (21%) had a GCS of 15, no neurologic symptoms, alcohol use or anticoagulation. Only 1 of 13 signs and symptoms correlated with ICI. In this study, no useful clinical predictors of intracranial injury in elderly patients with MHT were found. Current protocols based on clinical findings may miss 30% of elderly ICI patients. Head CT scan is recommended on all elderly patients with MHT.

Comparison of APACHE II, MEES and Glasgow Coma Scale in patients with nontraumatic coma for prediction of mortality. Acute Physiology and Chronic Health Evaluation. Mainz Emergency Evaluation System

INTRODUCTION

There are numerous prehospital descriptive scoring systems, and it is uncertain whether they are efficient in assessing of the severity of illness and whether they have a prognostic role in the estimation of the illness outcome (in comparison with that of the prognostic scoring system Acute Physiology and Chronic Health Evaluation [APACHE] II). The purpose of the present study was to assess the value of the various scoring systems in predicting outcome in nontraumatic coma patients and to evaluate the importance of mental status measurement in relation to outcome.

PATIENTS AND METHODS

In a prehospital setting, postintervention values of the Mainz Emergency Evaluation System (MEES) and Glasgow Coma Scale (GCS) were measured for each patient. The APACHE II score was recorded on the day of admission to the hospital. This study was undertaken over a 2-year period (from January 1996 to October 1998), and included 286 consecutive patients (168 men, 118 women) who were hospitalized for nontraumatic coma. Patients younger than 16 years were not included. Their age varied from 16 to 87 years, with mean +/- standard deviation of 51.8 +/- 16.9 years. Sensitivity, specificity and correct prediction of outcome were measured using the chi2 method, with four severity scores. The best cutoff point in each scoring system was determined using the Youden index. The difference in Youden index was calculated using the Z score. For each score, the receiver operating characteristic (ROC) curve was obtained. The difference in ROC was calculated using the Z score. P < 0.05 was considered statistically significant.

RESULTS

For prediction of mortality, the best cutoff points were 19 for APACHE II, 18 for MEES and 5 for GCS. The best cutoffs for the Youden index were 0.63 for APACHE II, 0.61 for MEES and 0.65 for GCS. The correct prediction of outcome was achieved in 79.9% for APACHE II, 78.3% for MEES and 81.9% for GCS. The area under the ROC curve (mean +/- standard error) was 0.86 +/- 0.02 for APACHE II, 0.84 +/- 0.06 for MEES and 0.88 +/- 0.03 for GCS. There were no statistically significant differences among APACHE II, MEES and GCS scores in terms of correct prediction of outcome, Youden index or area under ROC curve.

CONCLUSIONS

APACHE II is not much better than prehospital descriptive scoring systems (MEES and GCS). APACHE II and MEES should not replace GCS in assessment of illness severity or in prediction of mortality in nontraumatic coma. For the assessment of mortality, the GCS score provides the best indicator for these patients (simplicity, less time-consuming and effective in an emergency situation.

Use of a complete neurological examination to screen for significant intracranial abnormalities in minor head injury

Indications for head computed tomography (CT) scans are unclear in patients with nonpenetrating head injury and Glasgow Coma Scale (GCS) scores of 15. We performed a prospective study to determine if significant intracranial injury could be excluded in patients with GCS-15 and a normal complete neurological examination. A prospective trial of clinically sober adult patients with GCS = 15 on emergency department (ED) presentation after closed head injury with loss of consciousness or amnesia was conducted from May 1996 through April 1997. All subjects underwent a standardized neurological examination including mental status evaluation, and assessment of motor, sensory, cerebellar and reflex function before CT scan. During the study period, 58 patients met inclusion criteria. Fifty-five patients (95%) had normal CT scans and 23 (42%) had focal neurological abnormalities. Three patients (5%) had CT scan findings of acute intracranial injury, two of whom had normal neurological examinations. One patient had an acute subdural hematoma requiring emergent surgical decompression; the other had both an epidural hematoma and pneumocephalus that did not require surgery. Significant brain injury and need for CT scanning cannot be excluded in patients with minor head injury despite a GCS = 15 and normal complete neurological examination on presentation.

The conundrum of the Glasgow Coma Scale in intubated patients: a linear regression prediction of the Glasgow verbal score from the Glasgow eye and motor scores

BACKGROUND

The Glasgow Coma Scale (GCS), which is the foundation of the Trauma Score, Trauma and Injury Severity Score, and the Acute Physiology and Chronic Health Evaluation scoring systems, requires a verbal response. In some series, up to 50% of injured patients must be excluded from analysis because of lack of a verbal component for the GCS. The present study extends previous work evaluating derivation of the verbal score from the eye and motor components of the GCS.

METHODS

Data were obtained from a state trauma registry for 24,565 unintubated patients. The eye and motor scores were used in a previously published regression model to predict the verbal score: Derived Verbal Score = -0.3756 + Motor Score * (0.5713) + Eye Score * (0.4233). The correlation of the actual and derived verbal and GCS scales were assessed. In addition the ability of the actual and derived GCS to predict patient survival in a logistic regression model were analyzed using the PC SAS system for statistical analysis. The predictive power of the actual and the predicted GCS were compared using the area under the receiver operator characteristic curve and Hosmer-Lemeshow goodness-of-fit testing.

RESULTS

A total of 24,085 patients were available for analysis. The mean actual verbal score was 4.4 +/- 1.3 versus a predicted verbal score of 4.3 +/- 1.2 (r = 0.90, p = 0.0001). The actual GCS was 13.6 + 3.5 versus a predicted GCS of 13.7 +/- 3.4 (r = 0.97, p = 0.0001). The results of the comparison of the prediction of survival in patients based on the actual GCS and the derived GCS show that the mean actual GCS was 13.5 + 3.5 versus 13.7 + 3.4 in the regression predicted model. The area under the receiver operator characteristic curve for predicting survival of the two values was similar at 0.868 for the actual GCS compared with 0.850 for the predicted GCS.

CONCLUSIONS

The previously derived method of calculating the verbal score from the eye and motor scores is an excellent predictor of the actual verbal score. Furthermore, the derived GCS performed better than the actual GCS by several measures. The present study confirms previous work that a very accurate GCS can be derived in the absence of the verbal component.

Appropriate use of the Glasgow Coma Scale in intubated patients: a linear regression prediction of the Glasgow verbal score from the Glasgow eye and motor scores

The Glasgow Coma Scale (GCS) has been shown to be a valuable tool in assessing the neurologic and physiologic status of critically ill patients. Unfortunately, the GCS requires assessment of the verbal response of the patient and this can be blocked by intubation. The purpose of this study was to assess the ability of a regression model based upon the eye and motor components of the GCS to accurately predict the verbal response of the GCS. The primary hypothesis was that the verbal response could be derived from the motor and eye responses of the GCS.

METHODS

Data were collected prospectively in an intensive care unit computer data base. Patients were divided into training and test data sets. Linear regression was used to derive a model of verbal score from the motor and eye scores of the GCS in the training data set. Correlation between the actual and the predicted verbal scores was calculated.

RESULTS

A total of 2,521 GCS assessments were available for analysis. The second order multiple regression model was an accurate predictor of the verbal score (Pearson's Correlation r = 0.9, R2 = 0.8, p = 0.0001) in 1,463 observations in the training data set. Second Order Multiple Regression Model: Estimated GCS Verbal = (2.3976) + [GCS Motor x (-0.9253)] + [GCS Eye x (-0.9214)] + [(GCS Motor)2 x (0.2208)] + [(GCS Eye)2 x (0.2318)] where r = 0.91, R2 = 0.83, and p = 0.0001. The accuracy of this model was confirmed by comparing the predicted verbal score to the actual verbal score in the test data set (n = 736, r = 0.92, R2 = 0.85, p = 0.0001)

CONCLUSIONS

The GCS is a useful tool in the intensive care unit and a critical part of the APACHE II assessment of patient acuity. GCS has been shown to be a useful tool in its own right as a predictor of outcome in the critically ill. Its use is limited with intubation. (See Segatore M, Way C: Heart Lung 21:548, 1992; and Lieh-Lai MW, Theodorou AA, Sarnaik AP, et al: J Pediatr 120:195, 1992.) The present study demonstrates that a relatively simple regression model can use the eye and motor components of the GCS to predict the expected verbal component of the GCS, thus allowing the calculation of the GCS sum score in intubated patients.

Glasgow Coma Scale in the prediction of outcome after early aneurysm surgery

OBJECTIVE

A prospective study was performed to analyze whether the Glasgow Coma Scale (GCS) was useful in predicting the outcome after early surgical intervention for aneurysmal subarachnoid hemorrhage (SAH).

METHODS

In a consecutive series of 765 patients who underwent surgery for aneurysms within 7 days after SAH, the level of consciousness was assessed by the GCS just before surgery and the outcome was graded by the Glasgow Outcome Scale 6 months after surgery.

RESULTS

The patient distribution in accordance with the GCS sum scores in descending order from 15 to 3 was as follows: 334, 140, 58, 27, 20, 26, 27, 19, 26, 17, 20, 27, and 24 patients, respectively. In general, the higher the preoperative GCS score was, the better the surgical outcome was. The overall surgical result was significantly correlated with the preoperative GCS score (rs = 0.615, P < 0.001). With respect to the levels that distinguish the outcome along the GCS axis, a significant difference in the outcome was observed only between the GCS scores of 15 and 14 (P < 0.001, Wilcoxon test).

CONCLUSION

The GCS proved useful in the preoperative evaluation of patients with SAH, in terms of outcome prediction. It is suggested that the SAH scale proposed by the World Federation of Neurosurgical Societies be reexamined, because differences in outcomes were not clear between the GCS scores of 13 and 12 or between those of 7 and 6, in which Grades III and IV and Grades IV and V are differentiated in the scale, respectively.

Post-traumatic apallic syndrome following head injury. Part 1: clinical characteristics

Epidemiological studies made within the western countries indicate an incidence of 200-300 traumatic head injuries per 100 000 residents each year. Severe head injuries account for 5-25% of all head injuries; 10-14% of all severe head-injured patients develop into a vegetative state, in which a sleep-wake rhythm is apparent, but however in which there is no evidence of awakeness or reactivity to the environment. The most commonly used labels, in the German and international literature, for these patients are 'vegetative state', 'apallic syndrome' and 'coma vigile'. This clinical characterization is not sufficient. It is necessary to employ additional criteria to distinguish subsets of vegetative patients e.g. computerized tomography, magnetic resonance imaging, single photon emission tomography, electroencephalography, brainstem reflexes, evoked potentials, assessment scales, age, premorbid brain disorders. Diagnostic and prognostic parameters must form the basis for various decisions relating to patients' care and intervention.

The Head Injury Severity Scale (HISS): a practical classification of closed-head injury

The authors introduce a two-dimensional scale for rating closed-head injury, the Head Injury Severity Scale (HISS). This system is based on a five-interval severity classification (minimal through critical), determined primarily by the initial post-resuscitation Glasgow Coma Scale score. The second dimension is predicated on the presence or absence of complications, appropriate for each severity interval. The outcomes of almost 25,000 patients with head injury encountered at our institution over a 7-year period were evaluated. We discovered that adding a complication dimension to each severity category resulted in significant outcome differences and effectively divided patients into groups with very different risks, prognosis and treatment requirements. The HISS is proposed as a framework on which further research can be done to guide care to predict outcome and to perform audits on head-injured patients.

Predictors of hospital mortality in older patients with subdural hematoma

OBJECTIVE

To identify presenting characteristics of older patients with subdural hematoma who are unlikely to survive hospitalization.

DESIGN

A retrospective cohort.

PATIENTS

All patients > or = 65 years of age hospitalized at a tertiary care center from 1985-1990 with the primary diagnosis of subdural hematoma.

MEASUREMENTS

Chart review was performed to characterize presenting clinical characteristics, hospital course, and outcome at the time of hospital discharge.

MAIN RESULTS

Of the 157 eligible patients, 42% (66/157) were > or = 80 years of age. Although 30% of patients had no recorded trauma, 54% experienced a fall before hospitalization. Twenty-six percent (47/157) of patients had been on antithrombotic therapy (14 on coumadin, two on heparin, 31 on antiplatelet agents, one on both coumadin and an antiplatelet agent). Sixty percent of patients had no focal neurologic findings, and the mean Glasgow Coma Score was 12.3 (+/- 3.6). The hematoma was considered chronic in 49% (77/157) of cases, based on time from antecedent trauma or on neuroimaging criteria. Midline shift by neuroimaging was present in 69%. Overall hospital mortality was 31% (48/157). Using logistic regression to control for other factors, level of consciousness (Glasgow Coma Score < = 7) (OR = 10.4), age > or = 80 (OR = 3.7), duration of hematoma considered acute (OR = 2.7), and craniotomy (OR = 2.6) were significantly associated with hospital mortality. Presence of focal symptoms, previous antithrombotic medication use, nature of trauma, comorbidity score, and presence of midline shift were not associated with hospital mortality.

CONCLUSIONS

Among older patients with subdural hematoma, level of consciousness, extreme old age, duration of the hematoma, and nature of the intervention were significantly associated with hospital mortality. These factors should help physicians in clinical decision making and formulation of advance directives for geriatric patients with subdural hematoma.

A comparison of the Glasgow Coma Scale and the Swedish Reaction Level Scale

The Glasgow Coma Scale (GCS) and the Swedish Reaction Level Scale (RLS85), two level-of-consciousness scales used in the assessment of patients with head injury, were compared in a prospective study of 239 patients admitted to a regional head injury unit over a 4-month period. Assessments were made by nine staff members ranging from house officer to registrar, after briefing about the two scales. Data were also collected on age, nature of injuries, surgical treatment, and condition at discharge or transfer using the Glasgow Outcome Scale. Both the GCS and the RLS85 reliably identified comatose patients and those with minor head injury, but were much less effective in defining the response level in patients considered to have a moderate head injury. Only 41% of the patients allocated to a moderate-head-injury category by the GCS and the RLS85 were common to both groups. Where a mismatch occurred, neither scale allocated patients to a 'better' or 'worse' category more frequently than the other. Assessment of patients' conscious levels using the GCS was difficult in only two cases. One patient had facial injuries, and the other was intubated. The RLS85 was reported by all users to be simpler to use than the GCS, but the latter is much more widespread in use. Both scales function well in cases of severe and minor head injury, but have weaknesses when defining moderate head injury. Level-of-consciousness scales are only an aid to assessment and the final choice between the two scales must remain a matter of personal or departmental preference.

Limitations of neurological assessment in mild head injury

The authors have investigated two commonly used methods of assessing neurological status in patients with mild head injury to determine whether they can predict intracranial damage. Of 686 such patients with cranial computed tomography (CT) scans, scan results were recorded, along with total and motor components of the Glasgow Coma Scale (GCS) and the Reaction Level Scale (RLS85). Despite relatively normal admission neurological examinations, 127 of the 689 patients (18.4%) had intracranial lesions, and 38 (5.5%) required surgery. There was no significant difference in distribution of the GCS in patients with and without intracranial lesions. The RLS85 was superior to the GCS in predicting intracranial pathology, and a significant association between RLS85 and lesions on CT scanning was noted. However, even this test was normal in 19 patients found to have intracranial pathology, including nine who required surgery. The authors conclude that a normal or near-normal mental status examination in a head-injured patient on arrival at the emergency room is inadequate to exclude a potentially serious intracranial lesion. It is unlikely that further refinements in the clinical evaluation will result in diagnostic accuracy comparable with that of CT scanning. Accordingly, we recommend that any patient who has suffered a loss of consciousness or amnesia following head injury have an urgent cranial CT scan.

[Operational manual of the reaction level scale (RLS85)]

The Reaction Level Scale (RLS85) is a range scored coma scale (8 levels) for the assessment of responsiveness in patients with acute brain disorders. Its feasibility in clinical practice and for research studies has been verified in a multicentre study and by comparison with other current coma scales. Range scoring and absence of pseudoscoring are its most significant advantages over the other current scales. An operative manual of the RLS85 in Portuguese is standardized in this text which also provides a selected bibliography on the subject.

Reliability and accuracy of the Glasgow Coma Scale with experienced and inexperienced users

To investigate whether the Glasgow Coma Scale (GCS) can be used reliably and accurately by inexperienced observers, ratings made by observers grouped by level of experience were examined for within-group interobserver disagreements and for discrepancies with scores given by an expert. The GCS was used accurately by experienced and highly trained users, but inexperienced users made consistent errors. The errors were such that they would not be detectable by studies that examine only interobserver agreement, and they were substantial, averaging in some cases more than one point on the four-point and five-point scales of the GCS. Also, the error rates were highest at the intermediate levels of consciousness, for which the detection of changes in condition is vital. The findings support the continued use of the GCS by appropriately qualified personnel, but call into question much of the conventional wisdom about its reliability when used by untrained or inexperienced staff. The findings also suggest that interobserver comparisons are insufficient for establishing the viability of the GCS.

Severe traumatic brain lesions in Sweden. Part I: Aspects of management in non-neurosurgical clinics

This paper reports a study of 587 consecutive patients treated for severe traumatic brain lesions (coma greater than 6 hours) during 1977-1984. Epidemiology, management and outcome were documented in 425 patients during the first part of the study (1977-1982) as a basis for future efforts at improvements. A total of 70-80 patients with severe head injuries were admitted annually to the Department of Neurosurgery in Lund and 88.6% of these patients were referred from 14 local hospitals, most of which are situated more than 50 km from Lund. Half of the patients were older than 40 years and 25% older than 60. Focal intracranial mass lesions were diagnosed in 64% of the patients. In the total study 41% of the patients were described as 'talk and deteriorate' and 13% as 'talk and die'. In 1983 a protocol for primary management was introduced in all local hospitals in the region. The management protocol caused a significant decrease (p less than or equal to 0.05) in the number of explorative craniotomies in local hospitals and a virtual disappearance of late surgical procedures (greater than 6 hours after injury). A fall was observed in the number of patients arriving at the Department of Neurosurgery with respiratory insufficiency. The study illustrates the epidemiology of severe head injuries in Sweden and the present state of management of these patients in non-neurosurgical departments. It is concluded that an overall outcome comparable to other reported series is also feasible in regions with a relatively sparse population and large geographical distances provided that strict recommendations for initial management are given to the local hospitals.

A comparison of the Glasgow Coma Scale and the Reaction Level Scale (RLS85)

The Glasgow Coma Scale (GCS) and the Reaction Level Scale (RLS85) were compared for rating neurosurgical patients in regard to ranking order of deficit severity, interobserver variability, and coverage for relevant factors. Four physicians, four registered nurses, and four assistant nurses performed 72 pairwise ratings on 47 neurosurgical patients. The rank correlation between the GCS sum score and the RLS85 was -0.94, suggesting the same ranking order of severity and indicating that the underlying concepts of somnolence, delirium, and motor responses in coma are evaluated in the same way. By the sign test, the RLS85 was shown to have better interobserver agreement than the GCS sum score and the eye-motor-verbal (EMV) profile. The interobserver grading disagreements in both scales were distributed over the entire range of responsiveness, and for the GCS sum score they were slanted to combined segments 9 to 15. The RLS85 showed full coverage of relevant factors, while 43 (60%) of the 72 test occasions in the GCS sum score and the EMV profiles showed untestable features, most often because of patient intubation. The pseudoscore (that is, the choice of value given to untestable features) affects interobserver agreement as well as the estimated overall patient responsiveness in the GCS sum score. Assessment by the order of applying the scales showed a significant effect on the GCS eye-opening scale (p = 0.01) and the GCS sum score (p = 0.03), indicating a sensitivity to environmental stimuli unrelated to the patient's status. This study demonstrates that basically the same information as that found in the separate eye, motor, and verbal scales of the GCS can be combined directly into the RLS85, which has better interobserver agreement and better coverage than the GCS sum score.