[Show abstract][Hide abstract] ABSTRACT: Traumatic brain injury makes the brain vulnerable to secondary insults. Post-traumatic alterations in intracranial dynamics, such as reduced intracranial compliance (IC), are thought to further potentiate the effects of secondary insults. Reduced IC combined with intracranial volume insults leads to metabolic disturbances in a rat model. The aim of the present study was to discern whether a post-traumatic hypotensive insult in combination with reduced IC caused more pronounced secondary metabolic disturbances in the injured rat brain.
Rats were randomly assigned to four groups (n = 8/group): 1) trauma with hypotension; 2) trauma and reduced IC with hypotension; 3) sham injury with hypotension; and 4) sham injury and reduced IC with hypotension. A weight drop model of cortical contusion trauma was used. IC was reduced by gluing rubber film layers on the inside of bilateral bone flaps before replacement. Microdialysis probes were placed in the perimeter of the trauma zone. Hypotension was induced 2 h after trauma. Extracellular (EC) levels of lactate, pyruvate, hypoxanthine, and glycerol were analyzed.
The trauma resulted in a significant increase in EC dialysate levels of lactate, lactate/pyruvate ratio, hypoxanthine, and glycerol. A slight secondary increase in lactate was noted for all groups but group 2 during hypotension, otherwise no late effects were seen. There were no effects of reduced IC.
In conclusion, reduced IC did not increase the metabolic disturbances caused by the post-traumatic hypotensive insult. The results suggest that a mild to moderate hypotensive insult after initial post-traumatic resuscitation may be tolerated better than an early insult before resuscitation.
Full-text · Article · Nov 2010 · Upsala journal of medical sciences
[Show abstract][Hide abstract] ABSTRACT: Recent federal regulations allow for emergency research without prospective consent provided that additional protections for the subjects are provided. One of these is community consultation.
To determine how to feasibly consult the community and what to do with the findings.
In connection with an ongoing study of l-arginine for brain injury at a public hospital's trauma center, we consulted three sets of community representatives using different methods. To sample the entire population of the county, we conducted a random-digit dialing survey (456 residents). To sample individuals served by the hospital, we interviewed a convenience sample of 566 patients and individuals in the waiting area. To sample particularly interested individuals, we conducted a series of public meetings (114 participants). In each case, the same instrument was used to ascertain their attitudes toward the study in general and toward its major features (randomization, waiver of consent, location, risks/benefits). To control for framing effects, items were randomly presented in a positive or negative fashion.
All methods proved feasible, but telephone surveys were most efficient and guaranteed the desired demography. Even for a very low-risk study, only 79.75% of respondents would be willing to participate. The rate of approval for the major features was lower, with only 67.78% approving of the risk/benefit ratio, 53.7% approving of randomization, 57.66% approving of the consent waiver, and 44.45% approving of the location. The most significant factors affecting the rate of approval were the method of consultation and the framing of items (both p < .001), age, ethnicity, and previous research participation (all p < .01).
Community consultation is feasible, but its results depend heavily on method of consultation, framing of questions, and choice of community. It may well demonstrate unexpectedly substantial opposition. There needs to be a better definition of the process and a better understanding of how to respond to its results.
No preview · Article · Sep 2006 · Critical Care Medicine
[Show abstract][Hide abstract] ABSTRACT: The vulnerability of the brain is considered to be increased after trauma. The present study was undertaken to determine whether intracranial volume insults in the posttraumatic period led to increased metabolic disturbances if intracranial compliance was decreased.
A weight drop technique with a brain compression of 1.5 mm was used for injury. Intracranial compensatory volume was decreased 60 microl by placing rubber film between the dura mater and the bone. Intracranial volume insults were induced using the Bolus injection technique. Microdialysis was used to measure interstitial lactate, pyruvate, hypoxanthine, and glycerol. Fifty-two rats were allocated to trauma and sham groups with 0 to 3 layers of rubber film with and without intracranial volume insults.
In the groups with reduced intracranial volume exposed to intracranial volume insults, the time course of metabolic markers showed higher increases and slower recovery rates than for the other groups. Reduced intracranial volume or intracranial volume insults alone did not cause any changes compared with controls.
These results support the hypothesis that decreased intracranial compliance increases the vulnerability of the brain for secondary volume insults even with intracranial pressure at low levels between the insults. This finding has important clinical implications in that it stresses the need to identify patients with low intracranial compliance so that their treatment can be optimized.
[Show abstract][Hide abstract] ABSTRACT: The aims of this study were to get an impression of the relationships between intracranial compliance (IC) and Lactate/Pyruvate (L/P) ratio and temperature and L/P ratio, and to determine if patients with low IC had an increased vulnerability for the secondary insult hyperthermia (as reflected in the L/P ratio). The effects of coma treatment on the results were also studied.
Ten TBI patients were monitored for IC, in vivo microdialysis (MD) and bladder temperature. Mean Glasgow Coma Scale (GCS) score was 7 (range 4-10). Three patients underwent induced coma treatment. Three statistical models were used to look at the relationships between IC, temperature and L/P ratio in patients with and without coma.
We found that with high temperature L/P ratios increased as IC decreased (P < 0.0001). The patients with coma treatment had significantly higher average L/P ratios (P < 0.02). The effect of IC on the L/P ratio differed by coma treatment (P < 0.02). The temperature effect was not dependent on coma treatment (P < 0.49).
These findings suggest the importance of avoiding hyperthermia in TBI patients, especially in patients with low or decreased IC (monitored or anticipated). The present technical solution seems promising for analysis of complex clinical data.
No preview · Article · Mar 2006 · Journal of Clinical Monitoring and Computing
[Show abstract][Hide abstract] ABSTRACT: This study evaluated the prevalence and specificity of diagnostic criteria for postconcussional syndrome (PCS) in 178 adults with mild to moderate traumatic brain injury (TBI) and 104 with extracranial trauma. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and International Classification of Diseases (ICD-10) criteria for PCS were evaluated 3 months after injury. The results showed that prevalence of PCS was higher using ICD-10 (64%) than DSM-IV criteria (11%). Specificity to TBI was limited because PCS criteria were often fulfilled by patients with extracranial trauma. The authors conclude that further refinement of the DSM-IV and ICD-10 criteria for PCS is needed before these criteria are routinely employed.
Preview · Article · Feb 2005 · Journal of Neuropsychiatry
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to examine the patterns of change in microdialysate concentrations of glucose, lactate, pyruvate, and glutamate in the brain during periods of hypoxia/ischemia identified by monitoring brain tissue pO2 (PbtO2). Of particular interest was a better understanding of what additional information could be obtained by the microdialysis parameters that was not available from the PbtO2. Fifty-seven patients admitted with severe traumatic brain injury who had placement of both a brain tissue pO2 (PbtO2) and microdialysis probe were studied. The microdialysis probe was perfused with Ringer's solution at 0.3 microL/min and dialysate was collected at 1-h intervals. The concentration of glucose, pyruvate, lactate, and glutamate were measured in each dialysate sample. Changes in the microdialysis parameters were examined during episodes where the PbtO2 decreased to below 10 mm Hg. Ten episodes of tissue hypoxia/ischemia identified by a decrease in PbtO2 below 10 mm Hg were observed during the period of monitoring. The concentration of the dialysate glucose closely followed the PbtO2. The dialysate pyruvate concentration was more variable and in some patients transiently increased as the PbtO2 dropped below 10 mm Hg. The dialysate concentration of lactate was significantly increased as the PbtO2 decreased to less than 10 mm Hg. Dialysate glutamate was significantly elevated only when PbtO2 decreased to very low levels. Although changes in the PbtO2 provided the earliest sign of hypoxia/ischemia, the microdialysis assays provided additional information about the consequences that the reduced tissue pO2 has on brain metabolism, which may be helpful in managing these critically ill patients.
No preview · Article · Aug 2004 · Journal of Neurotrauma
[Show abstract][Hide abstract] ABSTRACT: While there has been strong evidence for the ability of neuropsychological performance at resolution of posttraumatic amnesia to predict later productivity, there has been less conclusive evidence for the relationship of neuropsychological test scores to concurrent productivity status. The purpose of the current study was to evaluate the relationship of neuropsychological test performance at 1 year post-injury to productivity assessed at the same time point. Participants were 518 persons with medically documented TBI who were enrolled in the TBI Model Systems Research and Demonstration Project. Stepwise logistic regression was utilized to determine the contributions of neuropsychological test scores to productivity after accounting for demographic characteristics, injury severity, and pre-injury productivity. Missing neuropsychological test scores were accounted for in the model. Variables that remained in the model and accounted for a significant proportion of the variance included age, duration of impaired consciousness, pre-injury productivity, and scores on measures of GOAT, Logical Memory II, and Trail Making Test, part B. The results indicate that neuropsychological test performance provides important information regarding the ability of persons with injury to return to productive activities. The results also indicate that inability to complete neuropsychological tests at 1 year post-injury is associated with non-productive activity.
Full-text · Article · Jun 2004 · The Clinical Neuropsychologist
[Show abstract][Hide abstract] ABSTRACT: Subarachnoid hemorrhage (SAH) is not an unusual disease in an elderly population. The clinical outcome has improved over time. It has been suggested that elderly SAH patients would benefit from endovascular aneurysm treatment. The aim of this study was to evaluate technical results and clinical outcome in a series of elderly SAH-patients treated with endovascular coil embolization. Sixty-two patients (> or = 65 years) presenting with aneurysmal SAH underwent early endovascular coil embolization at Uppsala University Hospital between September 1996 and December 2000. In all 62 cases included in the study, endovascular coil embolization was considered the first line of treatment. Admission variables, specific information on technical success, degree of occlusion and procedural complications, and outcome figures were recorded. Clinical grade on admission was Hunt and Hess (H&H) I-II in 39%, H&H III in 27% and H&H IV-V in 34% of the patients. The proportion of posterior circulation aneurysms was 24%. Coil embolization was successfully completed in 94%. The degree of occlusion of the treated aneurysm was complete occlusion in 56%, neck remnant in 21%, residual filling in 11%, other remnant in 5% and not treated in 6%. The rate of procedural complications was 11%. Outcome after 6 months was favorable in 41%, severe disability in 36% and poor in 22%. Favorable outcome was achieved in 57% of the H&H I-II patients, 47% of the H&H III patients and 17% of the H&H IV-V patients. Endovascular aneurysm treatment can be performed in elderly patients with SAH with a high level of technical success, acceptable aneurysm occlusion results, an acceptable rate of procedural complications and fair outcome results.
[Show abstract][Hide abstract] ABSTRACT: It is controversial whether a low cerebral blood flow (CBF) simply reflects the severity of injury or whether ischemia contributes to the brain's injury. It is also not clear whether posttraumatic cerebral hypoperfusion results from intracranial hypertension or from pathologic changes of the cerebral vasculature. The answers to these questions have important implications for whether and how to treat a low CBF.
We performed a retrospective analysis of 77 patients with severe traumatic brain injury who had measurement of CBF within 12 hours of injury. CBF was measured using xenon-enhanced computed tomography (XeCT). Global CBF, physiological parameters at the time of XeCT, and outcome measures were analyzed.
Average global CBF for the 77 patients was 36+/-16 mL/100 g/minutes. Nine patients had an average global CBF<18 (average 12+/-5). The remaining 68 patients had a global CBF of 39+/-15. The initial ICP was >20 mmHg in 90% and >30 mmHg in 80% of patients in the group with CBF<18, compared to 33% and 16%, respectively, in the patients with CBF>or=18. Mortality was 90% at 6 months postinjury in patients with CBF<18. Mortality in the patients with CBF>18 was 19% at 6 months after injury.
In patients with CBF<18 mL/100 g/minutes, intracranial hypertension plays a major causative role in the reduction in CBF. Treatment would most likely be directed at controlling intracranial pressure, but the early, severe intracranial hypertension also probably indicates a severe brain injury. For levels of CBF between 18 and 40 mL/100 g/minutes, the presence of regional hypoperfusion was a more important factor in reducing the average CBF.
No preview · Article · Mar 2004 · Neurocritical Care
[Show abstract][Hide abstract] ABSTRACT: The objectives of this study were to compare diagnoses of postconcussional syndrome between the International Classification of Diseases, 10th revision (ICD-10) and Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV). The patient sample was comprised of 178 adults with mild-moderate traumatic brain injury (TBI). The study design was inception cohort, and the main outcome measure was a structured interview 3 months after injury. The results were that, despite concordance of DSM-IV and ICD-10 symptom criteria (kappa=0.73), agreement between overall DSM-IV and ICD-10 diagnoses was slight (kappa=0.13) because fewer patients met the DSM-IV cognitive deficit and clinical significance criteria. Agreement between DSM-IV postconcussional disorder and ICD-10 postconcussional syndrome appears limited by different prevalences and thresholds.
Preview · Article · Feb 2004 · Journal of Neuropsychiatry
[Show abstract][Hide abstract] ABSTRACT: Much has been reported of the influence of age, affective symptoms, and satisfaction on self-ratings of health functioning, but little is known about the extent that race-based perceptions may have on influencing behavior or adjustment after a mild-to-moderate traumatic brain injury (MTBI). We investigated differences in perception of health functioning by race for mental and physical functioning using a global measure of health functioning. MTBI (n = 135) and general trauma (GT, n = 83) patients recruited from an area Level-1 trauma center at 3 months after injury were administered the Medical Outcomes Study: Short Form (SF-36), Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994), Community Integration Questionnaire, Social Support Questionnaire (SSQ), Center for Epidemiological Studies-Depression, and the Visual Analogue Scale of Depression. A significant interaction for Race Group (p < .01) was found on the Physical Component Scale (PCS) of the SF-36. In the MTBI group, African Americans reported worse functioning (p < .04) on the PCS scale; they perceived functioning on subscales General Health Perception (p < .02) and Physical Functioning (p < .04) to be more limited. On the SSQ, Hispanic MTBI patients reported having fewer social supports available to them (p < .05), although the race groups were comparable for satisfaction with their support. Rate of depression across groups was comparable, although subjective reporting by minority MTBI patients indicated greater depressed feelings. Differences in perception of health functioning may be related to the unique interaction created between sustaining an MTBI and variations in cultural expression of disability. Manifestations of physical difficulties may be better accepted for some cultures than having mental illness.
No preview · Article · Feb 2004 · Applied Neuropsychology
[Show abstract][Hide abstract] ABSTRACT: Traumatic brain injury causes a reduction in cerebral blood flow, which may cause additional damage to the brain. The purpose of this study was to examine the role of nitric oxide produced by endothelial nitric oxide synthase (eNOS) in these vascular effects of trauma. To accomplish this, cerebral hemodynamics were monitored in mice deficient in eNOS and wild-type control mice that underwent lateral controlled cortical impact injury followed by administration of either L-arginine, 300 mg/kg, or saline at 5 min after the impact injury. The eNOS deficient mice had a greater reduction in laser Doppler flow (LDF) in the contused brain tissue at the impact site after injury, despite maintaining a higher blood pressure. L-Arginine administration increased LDF post-injury only in the wild-type mice. L-Arginine administration also resulted in a reduction in contusion volume, from 2.4 +/- 1.5 to 1.1 +/- 1.2 mm(3) in wild-type mice. Contusion volume in the eNOS deficient mice was not significantly altered by L-arginine administration. These differences in cerebral hemodynamics between the eNOS-deficient and the wild-type mice suggest an important role for nitric oxide produced by eNOS in the preservation of cerebral blood flow in contused brain following traumatic injury, and in the improvement in cerebral blood flow with L-arginine administration.
No preview · Article · Nov 2003 · Journal of Neurotrauma
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to evaluate the extent and timing of impairment of cerebral pressure autoregulation after severe head injury.
In a prospective study of 122 patients with severe head trauma (median Glasgow Coma Scale Score 6), dynamic tests of pressure autoregulation were performed every 12 hours during the first 5 days postinjury and daily during the next 5 days. The autoregulatory index ([ARI] normal value 5 +/- 1.1) was calculated for each test. The changes in the ARI over time were examined and compared with other physiological variables. The ARI averaged 2.8 +/- 1.9 during the first 12 hours postinjury, and continued to decrease to a nadir of 1.7 +/- 1.1 at 36 to 48 hours postinjury. At this nadir, in 87% of the patients the value was less than 2.8. This continued deterioration in the ARI during the first 36 to 48 hours postinjury occurred despite an increase in cerebral blood flow ([CBF], p < 0.05) and in middle cerebral artery blood flow velocity ([BFV], p < 0.001), and could not be explained by changes in cerebral perfusion pressure, end-tidal CO2, or cerebral metabolic rate of O2. A marked decrease in cerebrovascular resistance ([CVR], p < 0.001) accompanied this deterioration in the ARI. Patients with a relatively higher BFV on Day 1 had a lower CVR (p < 0.05) and more impaired pressure autoregulation than those with a lower BFV.
The inability of cerebral vessels to regulate CBF normally may play a role in the vulnerability of the injured brain to secondary ischemic insults. These studies indicate that this vulnerability continues and even increases beyond the first 24 hours postinjury. Local factors affecting cerebrovascular tone may be responsible for these findings.
No preview · Article · Dec 2002 · Journal of Neurosurgery
[Show abstract][Hide abstract] ABSTRACT: Traumatic brain injury (TBI) remains a major public health problem globally. In the United States the incidence of closed head injuries admitted to hospitals is conservatively estimated to be 200 per 100,000 population, and the incidence of penetrating head injury is estimated to be 12 per 100,000, the highest of any developed country in the world. This yields an approximate number of 500,000 new cases each year, a sizeable proportion of which demonstrate significant long-term disabilities. Unfortunately, there is a paucity of proven therapies for this disease. For a variety of reasons, clinical trials for this condition have been difficult to design and perform. Despite promising pre-clinical data, most of the trials that have been performed in recent years have failed to demonstrate any significant improvement in outcomes. The reasons for these failures have not always been apparent and any insights gained were not always shared. It was therefore feared that we were running the risk of repeating our mistakes. Recognizing the importance of TBI, the National Institute of Neurological Disorders and Stroke (NINDS) sponsored a workshop that brought together experts from clinical, research, and pharmaceutical backgrounds. This workshop proved to be very informative and yielded many insights into previous and future TBI trials. This paper is an attempt to summarize the key points made at the workshop. It is hoped that these lessons will enhance the planning and design of future efforts in this important field of research.
Full-text · Article · Jun 2002 · Journal of Neurotrauma
[Show abstract][Hide abstract] ABSTRACT: Previous studies of postconcussional disorder (PCD) have utilized a dimensional approach (i.e., number and/or severity ratings of symptoms) to study postconcussional symptoms. This study used a syndromal approach (modified form of the DSM-IV criteria) for investigating risk factors for developing PCD, 3-months postinjury. The head trauma requirement was waived in order to determine specificity of symptoms to traumatic brain injury. Preliminary results from this ongoing study indicated significant risk factors including female gender, poor social support, and elevated self-reported depressive symptoms at 1-month postinjury. Comorbidities included concurrent diagnosis of major depressive disorder and/or posttraumatic stress disorder. Hispanics were significantly less likely to develop PCD than other racial/ethnic groups. PCD resulted more frequently from motor vehicle accidents and assaults. Screening tests for PCD risk factors/comorbidities performed shortly after injury (i.e., during routine follow-up clinic appointments) coupled with appropriate referrals for psychoeducational interventions and support groups may avoid prolonged loss of productivity and poor perceived quality of life in these patients.
No preview · Article · Jan 2002 · Journal of Clinical and Experimental Neuropsychology
[Show abstract][Hide abstract] ABSTRACT: To investigate the frequency and risk factors of major depressive disorder (MDD) after mild to moderate traumatic brain injury (TBI), 69 TBI and 52 general trauma (GT) patients were prospectively recruited and studied at 3-months postinjury. There was a nonsignificant difference in the proportion of MDD patients in the TBI and GT groups. Therefore, a composite MDD group (TBI and GT patients) was compared to patients who were nondepressed. Female gender was related to MDD, but no other risk factors were identified. MDD was associated with disability (Glasgow Outcome Scale, Community Integration Questionnaire) and cognitive impairment. MDD was comorbid with posttraumatic stress disorder. Implications for postacute management of mild to moderate TBI are discussed.
No preview · Article · Jan 2002 · Journal of Clinical and Experimental Neuropsychology
[Show abstract][Hide abstract] ABSTRACT: The elderly constitute a significant and increasing proportion of the population. The aim of this investigation was to study time trends in clinical management and outcome in elderly patients with subarachnoid hemorrhage.
Two hundred eighty-one patients >/=65 years of age with aneurysmal subarachnoid hemorrhage who were accepted for treatment at the Uppsala University Hospital neurosurgery clinic during 1981 to 1998 were included. Hunt and Hess grades on admission, specific management components, and clinical outcomes were recorded. Three periods were compared: A, 1981 to 1986 (before neurointensive care); B, 1987 to 1992; and C, 1993 to 1998.
The volume of elderly patients (>/=65 years of age) increased with time, especially patients >/=70 years of age. Furthermore the proportion of patients with more severe clinical conditions increased. A greater proportion of patients had a favorable outcome (A, 45%; B, 61%; C, 58%) despite older ages and more severe neurological and clinical conditions. In period C, Hunt and Hess I to II patients had a favorable outcome in 85% of cases compared with 64% in period A. This was achieved without any increase in the number of severely disabled patients.
Elderly patients with subarachnoid hemorrhage can be treated successfully, and results are still improving. The introduction of neurointensive care may have contributed to the improved outcome without increasing the proportion of severely disabled patients. A defeatist attitude toward elderly patients with this otherwise devastating disease is not justified.
[Show abstract][Hide abstract] ABSTRACT: The factors involved in the development of adult respiratory distress syndrome (ARDS) after severe head injury were studied. The presence of ARDS complicates the treatment of patients with severe head injury, both because hypoxia causes additional injury to the brain and because therapies that are used to protect the lungs and improve oxygenation in patients with ARDS can reduce cerebral blood flow (CBF) and increase intracranial pressure (ICP). In a recent randomized trial of two head-injury management strategies (ICP-targeted and CBF-targeted), a fivefold increase in the incidence of ARDS was observed in the CBF-targeted group.
Injury severity, physiological data, and treatment data in 18 patients in whom ARDS had developed were compared with the remaining 171 patients in the randomized trial in whom it had not developed. Logistic regression analysis was used to study the interaction of the factors that were related to the development of ARDS. In the final exact logistic regression model, several factors were found to be significantly associated with an increased risk of ARDS: administration of epinephrine (5.7-fold increased risk), administration of dopamine in a larger than median dose (10.8-fold increased risk), and a history of drug abuse (3.1-fold increased risk).
Although this clinical trial was not designed to study the association of management strategy and the occurrence of ARDS, the data strongly indicated that induced hypertension in this high-risk group of patients is associated with the development of symptomatic ARDS.
No preview · Article · Nov 2001 · Journal of Neurosurgery
[Show abstract][Hide abstract] ABSTRACT: Using a structured outcome interview, this study addressed the validity and sensitivity to change of the Glasgow Outcome Scale (GOS) and the Extended GOS (GOSE) in a prospective study of patients who sustained mild (n = 30) to moderate (n = 13) traumatic brain injury (TBI) or general trauma (n = 44). The patients were recruited from the emergency center or inpatient units of Ben Taub General Hospital and invited to participate in follow-up examinations at 3 and 6 months. Using a series of functional outcome measures, assessment of affective status, and neuropsychological tests as criteria, the validity of the GOSE generally exceeded the GOS. Analysis of the outcome data for the patients who completed both the 3-month and 6-month assessments disclosed that the GOSE was more sensitive to change than the GOS. Comparison of the 3-month outcome data disclosed that the GOSE and GOS scores did not differ for the TBI and general trauma groups. These findings lend further support for utilization of the GOSE in clinical trials when it is based on a structured interview.
No preview · Article · Jul 2001 · Journal of Neurotrauma
[Show abstract][Hide abstract] ABSTRACT: The relation between outcome and duration of adverse physiological events was studied, using suggested critical physiological values. Subjects were 184 patients with severe traumatic brain injury who received continuous monitoring of intracranial pressure (ICP), mean arterial pressure (MAP), cerebral perfusion pressure (CPP), and jugular venous oxygen saturation. Longer durations of adverse physiological events were significantly related to Glasgow Outcome Scale (GOS) scores and Disability Rating Scale (DRS) scores for all variables at all timepoints postinjury. When analyses excluded patients who died, the relation between adverse physiological events and GOS was nonsignificant; however, duration of ICP, MAP, and CPP still accounted for a significant portion of the variance in DRS scalres. The relative sensitivity of the GOS and DRS is discussed.
No preview · Article · Mar 2001 · Journal of Neurotrauma