Review of 1,000 consecutive cases of severe head injury treated before the advent of CT scanning

Mortality Reduction of Acute Surgery in Traumatic Acute Subdural Hematoma since the 19th Century: Systematic Review and Meta-Analysis with Dramatic Effect: Is Surgery the Obvious Parachute?

The rationale of performing surgery for acute subdural hematoma (ASDH) to reduce mortality is often compared with the self-evident effectiveness of a parachute when skydiving. Nevertheless, it is of clinical relevance to estimate the magnitude of the effectiveness of surgery. The aim of this study is to determine whether surgery reduces mortality in traumatic ASDH compared with initial conservative treatment. A systematic search was performed in the databases IndexCAT, PubMed, Embase, Web of Science, Cochrane library, CENTRAL, Academic Search Premier, Google Scholar, ScienceDirect, and CINAHL for studies investigating ASDH treated conservatively and surgically, without restriction to publication date, describing the mortality. Cohort studies or trials with at least five patients with ASDH, clearly describing surgical, conservative treatment, or both, with the mortality at discharge, reported in English or Dutch, were eligible. The search yielded 2025 reports of which 282 were considered for full-text review. After risk of bias assessment, we included 102 studies comprising 12,287 patients. The data were synthesized using meta-analysis of absolute risks; this was conducted in random-effects models, with dramatic effect estimation in subgroups. Overall mortality in surgically treated ASDH is 48% (95% confidence interval [CI] 44-53%). Mortality after surgery for comatose patients (Glasgow Coma Scale ≤8) is 41% (95% CI 31-51%) in contemporary series (after 2000). Mortality after surgery for non-comatose ASDH is 12% (95% CI 4-23%). Conservative treatment is associated with an overall mortality of 35% (95% CI 22-48%) and 81% (95% CI 56-98%) when restricting to comatose patients. The absolute risk reduction is 40% (95% CI 35-45%), with a number needed to treat of 2.5 (95% CI 2.2-2.9) to prevent one death in comatose ASDH. Thus, surgery is effective to reduce mortality among comatose patients with ASDH. The magnitude of the effect is large, although the effect size may not be sufficient to overcome any bias.

Prevalence of persistent vegetative state compared to recovery, disability, and death in subjects with severe traumatic brain injury: A meta-analysis

BACKGROUND

The persistent vegetative state has drawn considerable attention since it is the poorest result apart from mortality in subjects with severe traumatic brain injury. This meta-analysis was performed to evaluate its prevalence compared to recovery, disability, and death 6 months post severe traumatic brain injury.

METHODS

A systematic-literature search up to May 2020 was performed and 19 studies were detected with 10 368 subjects. They contained data about the subject's status 6 months post severe traumatic brain injury (recovery, disability, persistent vegetative state, and death). Odds ratio (OR) with 95% confidence intervals (CIs) was calculated comparing the prevalence of persistent vegetative state to that of recovery, disability, and death; 6 months post severe traumatic brain injury using the dichotomous method with a random- or fixed-effect model.

RESULTS

Significantly higher prevalence was found of recovery (OR, 0.08; 95% CI, 0.03-0.20, P < .001); disability (OR, 0.09; 95% CI, 0.06-0.15, P < .001); and death (OR, 0.07; 95% CI, 0.04-0.11, P < .001) compared to the prevalence of persistent vegetative state. The prevalence of persistent vegetative state was variable over time. Also, the prevalence of persistent vegetative states in developing countries was much higher than in developed countries.

CONCLUSIONS

However, persistent vegetative state is the poorest result apart from mortality in subjects with severe traumatic brain injury. Its prevalence is lower than the recovery, disability, and death even in developing counties with its lower healthcare services. The prevalence was variable over time and higher in developing countries. This relationship forces us to recommend improving healthcare services to the extent that a persistent vegetative state could be avoided as much as possible.

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.

Chronic vegetative state after severe head injury: clinical study; electrophysiological investigations and CT scan in 15 cases

Fifteen cases of chronic vegetative state (CVS), following severe head injury and lasting for two years or more, are reported. Vegetative state, in most instances after a period of coma, consists of a return of wakefulness accompanied by an apparent total lack of higher mental activity. A protracted period of vegetative state has been chosen to ensure that the possibility of further recovery could virtually be excluded. The term of CVS could therefore be reasonably used to designate these cases. Moreover, cerebral lesions were then thought to be the same as in neuropathological studies. Severe head injury, responsible for CVS, initially affected adults in 11 cases and children in four cases. The range of duration of the vegetative state was 2 to 14 years, with a mean of five years. The data of clinical study and electrophysiological investigations (EEG, brain stem auditory evoked potentials, somatosensory evoked potentials) are reported. A CT scan was carried out in each case to study the impairment of cerebral hemispheres and brain stem, with particular attention to the ventricular size. The results confirm that in the CVS, lesions affect mainly the hemispheres, while brain stem functions are mainly preserved. Vegetative State (VS) is the term proposed by Jennett and Plum (1972) to describe the condition that sometimes emerges after a period of coma, after a severe head injury (SHI). This condition consists of a return of wakefulness accompanied by an apparent total lack of higher mental activity. A practical definition of this state characterised by wakefulness without responsiveness is that the eyes open spontaneously and/or in response to verbal stimuli. Sleep-wake cycles exist. The patients can neither obey simple orders nor locate painful stimuli. They utter no comprehensible words. Blood pressure and breathing remain steady. It is much more difficult to specify exactly how long such a state must persist before it can be confidently declared permanent. Persistent vegetative state, or chronic vegetative state (CVS) is one of the five categories of the Glasgow Outcome Scale (Jennett and Bond, 1975). Bricolo et al (1980) think that the term CVS should never be applied before completion of the first year after the onset of traumatic coma. It actually seems possible to exclude the possibility of any further recovery after unresponsiveness for one year. The term CVS may then be rightfully used to denote this condition. For such protracted periods of VS, we have tried to state in a retrospective study the clinical and electroencephalographic (EEG) course.(ABSTRACT TRUNCATED AT 400 WORDS)

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

One hundred sixty-six papers published in seven neurosurgical journals from 1983 through 1985 have been surveyed to determine the methods used for assessment of overall patient responsiveness in acute cerebral disorders (coma grading). Fifty-one different coma scales or modifications were found. The Glasgow Coma Scale (GCS) sum score (that is, the sum of the scores of the individual eye, verbal, and motor scales) dominated (54%), and was used in 73 (76%) of 96 of the head-injury studies; in 56 (77%) of these 73 studies it was the single method of grading neurological status. The GCS sum score was used in 16 (23%) of 70 studies in patients with other etiologies. The Hunt and Hess scale was used in 26 (57%) of 46 reports of patients with subarachnoid hemorrhage. In 31 (55%) of the 56 studies of head injuries using the GCS alone, it was not obvious if the 12- or 13-grade scale was used. In 13 studies (23%) no reference to methodological investigations was made. In 44 papers (79%) the handling of untestable features, such as intubation or swollen eyes, was not reported. In the 56 studies using the GCS alone, coma was defined in many different ways and in 22 studies the definition of coma was not specified. In 63% of reports, the GCS sum score scale was combined in one to five groups of scores and this was done in 32 different ways. No information was available to describe the procedure of data aggregation or the reliability of the 13-grade GCS sum score. The lack of standardization makes it unnecessarily difficult to perform valid comparisons between different series of patients. Since the GCS sum score is the most widely used scale, it is suggested that the reporting of the GCS sum score should be standardized regarding pseudoscoring, coma definition, and use of combined scores. Further studies on the reliability of the GCS sum score are needed.

Changes produced by CT scanning in the outlook of severe head injury

This is a study of the changes that have occurred in the field of severe head injury since the advent of CT scanning, comparing two homogeneous series of patients selected by clinical status (Glasgow Coma Scale less than or equal to 8), namely a series of 1,000 cases admitted to our Department between 1973 and 1976, already published in this Journal, and one of 385 cases cared for between 1979 and 1980, when CT scanning had become generally available. The two series of patients compare very closely in many respects, particularly in the incidence of surgical cases. In the more recent series the overall outcome was better both in surgical and in non-surgical cases. Among patients in the CT scan series the incidence of brain contusion associated with haematoma was greater than that of pure subdural haematomas. In non-surgical patients the CT scan, unlike cerebral angiography, afforded better identification of traumatic lesions and the grouping of patients into homogeneous categories correlating with a given outcome. On admission, cerebral angiography and CT scanning were equally effective in detecting lesions of surgical import; later in the course of the illness, however, CT scanning proved far more effective in detecting changes, with fully 15% of the patients being referred for surgery in the light of repeat CT scan findings as opposed to only 4% undergoing surgery on the indications of repeat angiography. Also, in the new series the mean interval from injury to surgery was shorter, with 64% of patients being operated on within 6 hours of the injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Late post-concussional symptoms in traumatic head injury. An analysis of frequency and risk factors

During follow-up of 485 adult patients with traumatic head injury, 51% of the patients reported new post-concussional symptoms after an observation period of 3-5 years (mean 4.0 years). Most data, including the level of consciousness on admission, length of post-traumatic amnesia and days of hospitalization were poor parameters for predicting which patients would suffer late complications. A few variables were statistically of predictive importance: Sex, repeated head injury and skull fracture. Age was a risk factor for multiple complaints.

Prognosis and prediction of outcome in comatose head injured patients

Recent studies on the prognosis of comatose head injured patients have identified single powerful prognostic features at various time points during the first month after onset of coma. Using appropriate statistical methods even more powerful combinations of prognostic features can be selected. At each time point, optimal prediction requires sets of only 3 to 5 features. These features include depth and duration of coma as assessed by the Glasgow Coma Scale, pupil reactivity to light, age in decades, and spontaneous and reflex eye movements. In individual new patients, bedside predictions are now possible, e.g. using a booklet with prognosis tables like the one used in Rotterdam. Doctors actually learn by using these tables as they retain some of the information. However, the main application is that these tables permit one to evaluate whether differences in survival rates in different centres with different management regimes are due to a difference in management efficacy or to a difference in initial severity of injury.