Duration Of Coma Research Articles

Re-examining the concept of severity in traumatic brain injury.

This paper re-examines the theoretical concept of severe brain injury focusing on the duration of coma as a precise indicator of the clinical profile. A retrospective hospital chart study of 361 traumatic brain-injured patients was undertaken to determine the homogeneity of the subsample of the severely brain-injured (defined as 2 or more days of coma) with respect to the probability of four types of impairment: ataxia, contractures, paralysis and speech impairment. The current concept of severity assumes homogeneity among the 'severely brain-injured'. However, our results indicate significant differences in impairment within this population. The authors feel strongly that future studies must describe coma duration in finer gradations, and test for homogeneity within samples before inferences are made. Improvements in life-sustaining technologies have resulted in longer coma durations. The need to use coma days as an indicator of impairment rather than a broad category of severity is emphasized.

Post-coma disturbance and post-traumatic amnesia as nonlinear predictors of cognitive outcome following severe closed head injury: findings from the Westmead Head Injury Project.

This study sought to identify combinations of early neurological variables which best predict cognitive outcome 12 months after severe head injury. At the time of admission patients were assessed on seven neurological indices. Twelve months later a battery of neuropsychological tests examining recent memory functioning and speed of information processing was administered. Recent memory functioning was best predicted by a combination of post-coma disturbance (PCD; i.e. the duration of post-traumatic amnesia, PTA, minus the duration of coma) and presence of subarachnoid haemorrhage (multiple r = 0.54, p < 0.001). Speed of information processing was best predicted by the duration of PTA (r = 0.35, p < 0.01). However, these conclusions were based on square root transformation of PCD and PTA variables. The success of this transformation in assisting prediction confirms suggestions that the relationship between PTA and cognitive outcome is nonlinear.

Protective effect of Hachimi-jio-gan, an oriental herbal medicinal mixture, against cerebral anoxia

The protective effect of Hachimi-jio-gan (HJ) against cerebral anoxia was investigated with various experimental models in mice. Minimal effective dose of HJ which significantly prolonged the survival time was 0.5 g/kg, p.o. for normobaric hypoxia and 0.5 g/kg, p.o. for KCN- (4 mg/kg, i.v.) induced anoxia. HJ reduced the duration of coma induced by a sublethal dose of KCN (1.8 mg/kg, i.v.) in a dose-dependent manner. Furthermore HJ potentiated the anti-anoxic effect of physostigmine and the effect of HJ was diminished by the treatment with atropine.

The relation between neurological trauma parameters and long-term outcome in children with closed head injury

In a study of 54 children with closed head injury, the relation between neurological severity indicators and the occurrence of long-term sequelae was investigated. Patient data were recorded during the clinical phase and during a 2 year follow up period. A correlation analysis identified early predictors for the occurrence of long-term sequelae. In particular, the duration of coma and of post-traumatic amnesia correlated strongly with the occurrence of neurological, behavioural and intellectual residual sequelae but not with the more subjective complaints.

The relationship of duration of coma to long term outcome of victims of neurobehavioral brain injury

The relationship of duration of coma to long term outcome of victims of neurobehavioral brain injury

A review of the evidence for the effectiveness of sensory stimulation treatment for coma and vegetative states

Abstract This paper reviews fourteen studies that evaluate the efficacy of sensory stimulation treatment for patients in coma and vegetative states. The studies are divided according to whether they use outcome statistics, behaviour change, or physiological measures as their means of evaluation. There is also a review of the methodological considerations incumbent in research in this area. The authors conclude that sensory stimulation can alter behaviour in the unconscious patient and can reduce the duration of acute coma, and that further research is certainly warranted for economic as well as humanitarian reasons.

Neuropsychological Outcome and Social Recovery of Head-injured Patients

The Wechsler Adult Intelligence Scale and Yatabe-Guilford personality test were administered to 123 patients hospitalized for head injury who had made a relatively good recovery. Intelligence quotient (IQ) was correlated with clinical condition based on the Glasgow Coma Scale and duration of coma. More severely injured patients tended to show a greater decline in IQ. The type of lesion, as described by computed tomography, was also an important factor in predicting the outcome of intellectual function. The mean IQ of patients with diffuse injury, such as diffuse axonal injury and diffuse brain swelling, and intracerebral hematoma, was significantly lower than that of the control subjects, especially performance IQ (PIQ). Several patients demonstrated improved IQ level during the initial year. In particular, PIQ improved more than verbal IQ. The difference between the IQ of patients achieving social recovery and not was significant (p < 0.001). Causes of difficulty in returning to previous work were decreased IQ and personality change, such as lack of cooperativeness. Neuropsychological evaluation is important in predicting social recovery and selecting necessary neuropsychological rehabilitation.

Alternatives to the glasgow coma scale as a quality of life predictor following traumatic brain injury

Conventional "staging " of traumatic brain injury (TBI) typically uses depth of coma assessed by the Glasgow Coma Scale (GCS) score near admission as a severity marker. Frequently, early GCS scores are contaminated by alcohol or drug ingestion and other, nonneurological organ system trauma. As well, this measure's usefulness is limited due to its restricted range in survivors. Here we explore the utility of using length of posttraumatic amnesia, coma duration, and age as indirect markers of severity. Cluster analytic techniques were used to examine the relationship of severity so defined to long-term outcome in 106 mild, moderate, and severe TBI patients. Results indicate complex relationships between cluster groups with the influence of age of patient being highlighted as an important moderator in determining severity of injury and later psychosocial outcome.

Memory for Source After Traumatic Brain Injury

A fame judgment task was used to distinguish subjects" ability to recognize previously presented information from their ability to recognize the source of that information. Traumatic brain injured (TBI) subjects were impaired relative to controls with respect to verbal recall and recognition as well as memory for source. However, memory for source was demonstrated to be independent of explicit indices of recall and recognition ability. It was also found to be an extremely sensitive index of coma duration in the TBI subjects. The anticipated relationship between source memory and a putative index of frontal function (Wisconsin Card Sorting Test) was modest relative to the relationship between source memory and subjects" performance on a complex visual pattern matching task (Benton Facial Recognition), raising questions about hypothesized cognitive and neurophysiological mechanisms underlying memory for source.

The Paradoxical Anticonvulsive and Awakening Effect of High-Dose Pyridoxine Treatment for Isoniazid Intoxication-Reply

In Reply.— De' Clari raises some interesting points regarding the potential awakening effect of pyridoxine and makes an argument for pyridoxine infusions in comatose isoniazid-poisoned patients. There are two likely mechanisms by which pyridoxine may reverse isoniazid-induced coma. First, pyridoxine is a cofactor in the transamination reaction between γ-aminobutyric (GABA) and a-ketoglutaric acid—a reaction responsible for GABA degradation. 1 The second mechanism is based on de' Clari's observation of a rapid efflux of isoniazid from the peripheral to the vascular compartment. This efflux would provide a mechanism for a reduction of central nervous system isoniazid levels. By binding to isoniazid (as pyridoxine is known to do), 2 the levels of active circulating isoniazid may be reduced. It is unknown to what degree these two mechanisms are operative in reducing the depth and duration of isoniazid-induced coma. We have some concerns regarding a continuous infusion of pyridoxine for comatose patients. One

Comparison of artemisinin suppositories with intravenous artesunate and intravenous quinine in the treatment of cerebral malaria

Seventy-nine comatose cerebral malaria patients given standard supportive treatment were randomized to receive specific antimalarial chemotherapy of intravenous quinine, intravenous artesunate, or artemisinin suppositories. Artesunate and artemisinin reduced peripheral asexual parasitaemia significantly more rapidly than quinine (90% clearance time 16 h, 18·9 h and 34·5 h respectively), but did not significantly reduce the duration of coma or mortality. The rapid lowering of peripheral parasitaemia may not ameliorate complications already present. These results demonstrate that artemisinin suppositories are as effective as artesunate and quinine given intravenously, and have economic and practical advantages for the treatment of severe malaria in areas remote from major medical centres. However, large numbers of patients will need to be studied if differences in mortality between the 3 treatment groups are to be demonstrated.

Head-injured subjects aged over 50 years: correlations between variables of trauma and neuropsychological follow-up.

Neuropsychological follow-up was studied in 70 consecutive head-injured subjects aged over 50 years. Diffuse deterioration (28%), moderate deterioration (25%) and dementia (21%) were the most frequent sequelae. Analysis of correlations between neuropsychological sequelae and trauma variables showed that: (1) mild trauma did not necessarily imply good prognosis and could be followed by very severe consequences; (2) duration of post-traumatic amnesia was correlated with coma duration but not with neuropsychological outcome; (3) on the whole, no prognostic predictor of the outcome was found.

Temporally related changes of sleep complaints in traumatic brain injured patients.

Sleep complaints were obtained from 22 hospitalised patients with traumatic brain injury of recent onset (median 3.5 months after injury) and were compared with those of 77 discharged patients who had sustained brain injury about two to three years (median 29.5 months) previously. A high incidence of sleep complaints was noted in both groups (72.7% and 51.9% respectively). Disorders in initiating and maintaining sleep (DIMS) were the most common complaints among hospitalised patients (81.2%), whereas disorders of excessive somnolence (DOES) were common in discharged patients (72.5%). This difference in the nature of the complaints was apparently due to differences between the two groups in the time elapsed since injury, duration of coma, and immediate environmental conditions. In discharged patients with sleep complaints, neurobehavioural impairments and a poorer occupational outcome were more common than in those discharged patients without sleep complaints. It is suggested that early evaluation and treatment of sleep disturbances must be considered an integral part of the rehabilitation process.

Prophylactic phenobarbitone in young children with severe falciparum malaria: pharmacokinetics and clinical effects.

1. A method is described for the measurement of phenobarbitone (PB) by reversed phase high performance liquid chromatography (h.p.l.c.) from small samples of whole blood dried onto filter paper strips. 2. The disposition of PB given prophylactically to young children with severe malaria on parenteral quinine is contrasted with that in aparasitaemic Kenyan children on no antimalarial drugs. There were no differences in the disposition of PB between the two groups. 3. Peak blood PB concentrations were equal to or greater than 15 mg l-1 in 27% of the patients on quinine and 23% of those not on quinine; a concentration of 10 mg l-1 was achieved or exceeded by 100% and 92% of each group, respectively, and was maintained for 39 +/- 24 h (mean +/- s.d.), and 33 +/- 21 h, respectively. 4. In an open, dose-finding study, the progress of young children with cerebral malaria given prophylactic PB (10 mg kg-1), was contrasted with that of controls given no seizure prophylaxis. 5. The drug had no apparent effect on depth or duration of coma, but neither was the incidence of seizures reduced. 6. A controlled trial of prophylactic PB in young children with cerebral malaria is needed, but a larger dose than 10 mg kg-1 should be studied.

Limitations of the Glasgow Coma Scale in predicting outcome in children with traumatic brain injury

To study the hypothesis that, in the absence of an ischemic-hypoxic state, children with severe traumatic brain injury and with unfavorable Glasgow Coma Scale scores may have good recovery. Retrospective, observational, cross-sectional study with factorial design. Inpatient population in a university hospital. Seventy-nine children with traumatic brain injury admitted to the intensive care unit. All patients received close monitoring and strict control of intracranial pressure (less than 20 mm Hg) and cerebral perfusion pressure (greater than 60 mm Hg). Admission Glasgow Coma Scale score, survival, need for cardiopulmonary resuscitation, presence of shock, peak intracranial pressure, duration of coma, Glasgow Outcome Scale score, and the results of neuropsychologic tests were analyzed. Of 79 children, 70 (89%) survived. Although the mortality rate was higher among patients with Glasgow Coma Scale scores of 3 to 5, 14 (64%) of 22 of these children survived. Nonsurvivors had a significantly higher incidence of shock and need for cardiopulmonary resuscitation. Except for two patients who had prolonged hypoxemia, all children, including those with Glasgow Coma Scale scores of 3 to 5, had a satisfactory outcome (Glasgow Outcome Scale scores of 4 or 5). Neuropsychologic outcome was not significantly different in the survivors with Glasgow Coma Scale scores of 3 to 5 and those with Glasgow Coma Scale scores of 6 or more. A low Glasgow Coma Scale score does not always accurately predict the outcome of severe traumatic brain injury; in the absence of hypoxic-ischemic injury, children with traumatic brain injury and Glasgow Coma Scale scores of 3 to 5 can recover independent function.

Prediction of motor status 3 and 6 months post severe traumatic brain injury: a preliminary study.

The prediction of outcome following severe traumatic brain injury has received considerable attention in recent years. Previous prediction studies have focused on a long-term follow-up or prediction period. The reported outcome measures generally adopted a global approach (e.g. independent living) in terms of the prediction of physical function. The objective of the present study was to construct clinically useful predictive equations of motor system status, as represented by selected postural reactions (indicators of central nervous system function). Specifically, these equations would serve to predict the recovery of equilibrium and protective reactions both at 3 and 6 months post-injury, respectively. A stepwise multiple logistic regression analysis was performed, where nine predictive variables were considered using a multivariate approach. The results indicate that coma duration followed by age contribute significantly to the predictive capability of the models at both 3 and 6 months post-injury. Specifically, at 3 months, the predictive variables 'coma duration' and 'age' enabled an 84.62% correct prediction rate, whereas, at 6 months, 'coma duration' and 'age' enabled a 79.49% correct prediction rate. In addition, the exact probabilities (for given sample ages and coma durations) and associated 95% confidence intervals were calculated based on the predictive models obtained. The theoretical framework underlying these predictive models can form the basis for further studies. Furthermore, these preliminary predictive models have potential implications for early treatment planning and patient management.

Problems and changes after traumatic brain injury: differing perceptions within and between families.

This study is an attempt to characterize subgroups of families based on differing perceptions of problems and changes after traumatic brain injury. The Problem Checklist of the NYU Head Injury Family Interview was administered to 34 people with head injuries (PHI), and a significant other (SO) of each, between 1 and 3 years post-injury. Families were found to differ systematically in their responses and could be divided into three groups: High Agreement group (HAF), where there was high agreement between the PHI and the SO regarding problems and changes; High Disagreement--PHI endorsing more problems than the SO (HD-PHI); and High Disagreement--SO endorsing more problems than the PHI (HD-SO). No differences were found between these groups in age, sex, duration of coma, time since injury, educational achievement of the PHI, or the SO's relationship to the PHI. However, the HD-PHI group tended to have a higher return-to-work rate, the SOs in the HAF group reported the highest rates of subjective burden, and groups were found to differ in types of items endorsed by the PHI v. the SOs. Implications of findings are discussed regarding reliability of reporting problems, awareness issues in return to work and subjective burden of family members, and methodological and treatment issues.

Rehabilitation after severe head injury.

123 survivors of severely head injured patients presenting with coma grade III show a decreasing mean duration of coma with increasing age. The numbers and frequency of good recovery decrease, whereas poor recovery increases with age. Increase of the duration of coma grade III produces an increase of the mean latency and time of recovery and of the frequency of poor recovery, regardless of the age of the patients. Increasing age does not increase the mean latency and time of recovery systematically. The important conclusion of this analysis is, that the clinical feature of coma grade III, corresponding to GCS score of 4 and RLS of 6 and 7, indicates a different kind of brain damage at various age groups. It represents a lesser degree of brain damage for younger patients under 20, than for those over 20. In our opinion our observations do not demonstrate a better capacity of recovery of the young patients: but the young patients show a more severe clinical picture than the older patients do, if only the clinical syndrome of coma grade III with extensor rigidity, is considered as a yardstick for comparison.

Predicting clearing of post-traumatic amnesia following closed-head injury

The ability to predict the resolution of post-traumatic amnesia (PTA) early in the course of acute rehabilitation was studied in a sample of 98 closed-head injury (CHI) patients admitted for acute rehabilitation. The subjects' age, length of coma, time post-injury and Orientation Group Monitoring System (OGMS) subscale and aggregate scores were evaluated for the ability to predict if and when a patient would clear PTA. The results indicated that the combination of time post-injury and week one OGMS aggregate score provided the best prediction of whether and when PTA would clear. A shorter time from injury to acute rehabilitation was a positive prognostic indicator, accounting for more variance than either age or duration of coma. Whereas the aggregate OGMS score was a better indicator than any of the subscale scores, the results also suggested that specific aspects of cognition have differential predictive power, which may derive from different types of injury to the brain. Although the prediction model was statistically significant, its practical significance was limited. In particular, the high base rate for clearing PTA, 83.7%, attenuated the potential for differential prediction. Finally, this study provided additional support for the construct validity of the OGMS as a measure of cognitive function during the acute phase of recovery from CHI.

Effect of a novel calcium antagonist AE0047 on several models of cerebral ischemia

AbstractWe examined the cerebral protective effects of AE0047 employing cerebral ischemia models. In the bilateral carotid arterial occlusion model (BCAO) employing spontaneously hypertensive rats (SHRs), oral administration of AE0047 (0.1–0.3 mg/kg) or nicardipine (3 mg/kg) improved the neurological symptoms by 2 hr after the BCAO procedure and energy metabolite changes 30 min after the BCAO procedure. AE0047 was significantly effective in these 2 models at one‐tenth the dosage of nicardipine. Dihydroergotoxine completely protected in an adrenaline‐induced lethality model. AE0047 also showed a protective action in this model and is considered to have an α‐adrenergic blocking action similar to dihydroergotoxine. In the KCN‐induced abnormal behavior (the coma and the disappearance of searching behavior) and death models, protective effects were observed in the AE0047 group, but not in the nicardipine group. Protective action was marked even 2–4 hr after AE0047 administration. Dihydroergotoxine also shortened the duration of coma and prolonged the survival time, but had no effect on mortality. From these results, it is suggested that the α‐adrenergic blocking action of AE0047 participates in the antihypertensive action. The protective effects of AE0047 were most striking at 2 and 4 hr after AE0047 administration. © 1992 Wiley‐Liss, Inc.