Guidelines for the management of severe head injury. Brain Trauma Foundation.
Explore the source record for details and available documents.
Brain Injuries↗
Biomedical subjects
R M Chesnut
Publications and source records attributed to R M Chesnut.
Urinary retention and space-occupying lesions of the frontal cortex.
The authors present 2 cases in which urinary retention was related to supratentorial cortical lesions. These cases support the presence and function of a supratentorial center involved in control of the voiding reflex loop and indicate that lesions affecting this center can result in urinary retention rather than the syndrome of incontinence, urgency, and increased urinary frequency that is generally attributed to dysfunction of this system. In such cases, a clinical presentation of urinary retention in the absence of associated remarkable neurological deficits renders clinical evidence as a localizing sign.
Aged↗
Variability of vascular territory in stroke. Pitfalls and failure of stroke pattern interpretation.
BACKGROUND AND PURPOSE: We investigated the efficacy and feasibility of determining infarction mechanisms and underlying embolic or hemodynamic pathologies from topographical patterns of ischemic damage seen on computed tomography or magnetic resonance imaging. METHODS: Infarction patterns from 22 patients with ipsilateral severe, hemodynamically relevant carotid stenosis (n = 6) or occlusions (n = 16) were superimposed, using two matching algorithms, onto maps showing the variability of the cerebral vascular territories as determined from recent cadaver studies. These images were used to classify the infarctions as border-zone or territorial for the two conditions of minimal and maximal middle cerebral artery distribution. RESULTS: Classification of infarction patterns resulting from carotid stenosis was independent of the territorial extension map chosen: 83% were classified as territorial. Classification of patterns due to carotid occlusion, however, varied highly; 81% of infarctions were considered territorial when the maximal middle cerebral artery distribution map was used, whereas only 19% were when the minimal territorial extension map was used. CONCLUSIONS: The current concept that stroke mechanisms can be inferred from the interpretation of stroke patterns seen on computed tomography scans or magnetic resonance imaging is significantly confounded by the demonstrated variability in intracranial vascular distributions. Stroke pattern interpretation appears to be highly dependent on the in vivo vascular tree of the individual, which is unknown to the examiner. This calls into question the reliability of classifying infarction patterns as border-zone or territorial. Determination of true underlying stroke mechanisms requires a comprehensive approach and cannot be based solely on stroke pattern interpretation.
Brain↗
Secondary brain insults after head injury: clinical perspectives.
Secondary brain insults, particularly hypotension (systolic blood pressure < 95 mm Hg) and hypoxia (PaO2 < 60 torr), are the most powerful determinants of outcome from severe head injury (SHI) that are amenable to therapeutic manipulation. Well over one quarter of SHI patients appear to suffer one or more secondary insults during the time between injury and resuscitation. Furthermore, although improved strategies for airway management have decreased the incidence of preresuscitation hypoxia, little progress has been made in ameliorating the influence of hypotension during this period. The incidence of hypotension in the ICU is also > 25%, and such episodes also appear to be significant predictors of poor outcome independent of their etiologies and of preresuscitation secondary insults. In all, over one third of all SHI patients appear to experience one or more secondary insults during their acute post-injury course, and these events are correlated with a doubling of mortality and a large increase in morbidity. The approach to proper management of such secondary brain insults requires only an increased recognition of their importance, greater vigilance toward monitoring, and improved application of therapeutic maneuvers that are generally already available. Given their prevalence and impact on outcome, prevention/correction of secondary brain insults may be the most powerful means of improving outcome from severe brain injury available today.
Brain Diseases↗
Intracranial pressure and cerebral perfusion pressure in severe head injury.
Monitoring and management of intracranial pressure (ICP) are fundamental to modern neurotraumatology. Although never formally proven to independently improve outcome in prospective, randomized, placebo-controlled trials, there is such a predominance of indirect support for this modality that most neurotrauma protocols are impossible with-out its inclusion and ethical considerations virtually preclude placebo-controlled trials of its efficacy. In addition to the question of improving outcome, ICP monitoring is also useful in guiding the use of potentially harmful treatment modalities such as hyperventilation, mannitol, and barbiturates, and also provides important prognostic data. ICP monitoring provides information on the likelihood of cerebral herniation and allows calculation of the cerebral perfusion pressure (CPP). Although there is no constant threshold for herniation, the most commonly used treatment threshold is 20 to 25 mm Hg. In addition, ICP trends are indispensable in providing the earliest possible indication of critical intracranial mass effects when combined with other clinical indicators. CPP is the difference between mean arterial pressure and ICP. CPP is an important clinical indicator of cerebral blood flow (CBF). Cerebral autoregulation generally remains at least partially preserved after severe head injury, although the CPP value at which it is activated appears to be shifted upward. Therefore, maintaining adequate CBF appears to require using an elevated minimal CPP threshold when treating the injured brain. A generally accepted value of 70 mm Hg is suggested.
Brain Ischemia↗
Medical management of severe head injury: present and future.
The comparative efficacy of various treatment algorithms in improving outcome from severe head injury (SHI) has never been tested in a prospective, randomized, controlled trial. Indeed, there are few hard data on the influence on outcome of most of the individual treatment modalities used alone. The medical management algorithm presented here is an exercise in evaluating the strength of what studies do exist and attempting to balance the relative risk/benefit ratios of the various treatment modalities. This algorithm, based on the information contained in this issue of New Horizons, divides the patient's course into two segments based on the insertion of an intracranial pressure (ICP) monitor. Before the establishment of ICP monitoring, based on the devastating effects of secondary insults on the injured brain, the main emphasis should be on full resuscitation of the patient. Any "prophylactic" treatment of the intracranial injury that has the potential of interfering with full resuscitation (e.g., mannitol) or inducing secondary ischemic insults (e.g., hyperventilation) should be reserved for the specific instance of evidence of herniation or neurologic deterioration; if such deterioration should occur, however, it should be promptly treated. Following computed tomography imaging and any necessary surgical procedures, and ICP monitor should be inserted and treatment directed specifically toward controlling ICP and maintaining a cerebral perfusion pressure > or = 70 mm Hg. An algorithm for treating intracranial hypertension is presented, based on the successive application of effective agents with increasing attendant risks. Outside of the burgeoning pharmacologic approaches to the injured brain, the future of the management of SHI involves: a) subjecting the various protocols and treatment modalities presently in use to prospective, randomized, controlled trials in order to formally establish their utility; b) developing organized, regionalized trauma care systems which facilitate the universal delivery of the level of care necessary to effectively apply today's head injury management protocols; and c) furthering our development of targeted therapy in treating SHI. Targeted therapy involves recognizing and understanding the various pathophysiologic processes that occur in the injured brain over the acute course of treatment and the responses of these processes to various treatment modalities. Such processes include vasogenic and cytotoxic edema, increased cerebral blood volume, altered cerebrovascular autoregulation, vasospasm, etc.(ABSTRACT TRUNCATED AT 400 WORDS)
Algorithms↗
Metallic spinal artifacts in magnetic resonance imaging.
STUDY DESIGN: The magnetic resonance artifact susceptibility of traces of surgical aluminum, titanium, and stainless steel in a human spine model was investigated. Metallic filings were deposited in noncontiguous disc spaces in five human thoracic spines before magnetic resonance imaging with spin echo and gradient echo sequences. OBJECTIVES: Spin echo and gradient echo sequences were used for quantitate and compare void artifact produced by commonly used surgical metals. This was compared to a liquid paraffin control. SUMMARY OF BACKGROUND DATA: No significant susceptibility artifact was seen with any metal in all spin echo sequences, including T1 (TR 600, TE 12), T2 (TR 2000, TE 30), proton density (TR 2000, TE 80), and fast T2 scanning (TR 3800, TE 96, Ef). METHODS: Sagittal magnetic resonance imaging permitted void artifact quantification and comparison between different metallic alloys. Two neuroradiologists, working on a blinded basis, evaluated all data and rated the void susceptibility artifact on a scale of 1 (least) to 4 (greatest). RESULTS: In general, the magnitude of an imaging artifact during magnetic resonance imaging correlated with the magnetism of the metal. Nickel, found in a larger concentration in 316L than in 304 stainless steel, decreases the magnetic resonance artifact of specific metals because of its ability to stabilize iron in a non-magnetic state. Therefore, the 316L stainless steel yielded less artifact production than 304 stainless steel on gradient echo imaging. CONCLUSION: If upon gradient echo imaging in the postoperative period significant artifact production is noted, stainless steel deposition should be suspected as the causative agent. In this situation, spin echo techniques should be the first approach for attempting optimal visualization of the spinal cord and soft tissue structures.
Aged↗
Computed tomography of the brain: a guide to understanding and interpreting normal and abnormal images in the critically ill patient.
The computed tomography (CT) diagnosis of the neurologically impaired patient, both initially and as it evolves over time, is a critical factor in determining treatment and prognosis. As an integral part of the management team, it is vital that the critical care nurse have a firm understanding of the various diagnoses on an anatomic level. This article attempts to provide the fundamentals for understanding the technology and uses of CT imaging as well as performing a basic interpretation of normal and abnormal CT images in a variety of disease states.
Brain Diseases↗
Early, routine paralysis for intracranial pressure control in severe head injury: is it necessary?
OBJECTIVE: To investigate the efficacy of early, routine use of neuromuscular blocking agents for intracranial pressure management in patients with severe head injury. DESIGN: Retrospective review of data from the Traumatic Coma Data Bank. The Traumatic Coma Data Bank was a collaborative project of the National Institute of Neurological Disorders and Stroke that involved four Level I trauma centers. The Traumatic Coma Data Bank prospectively collected data on 1,030 severe head-injured patients (Glasgow Coma Score of < or = 8) between 1984 and 1987. SETTING: Four Level I trauma centers coordinated by the National Institute of Neurological Disorders and Stroke. PATIENTS: A total of 514 Traumatic Coma Data Bank patients who met study inclusion criteria were divided into two groups: group 1 consisted of 239 patients who were pharmacologically paralyzed starting within the first intensive care unit (ICU) shift or < or = 6 hrs into the second shift and lasting for at least 12 hrs. Group 2 contained the remaining 275 patients who did not fulfill these criteria. MEASUREMENTS AND MAIN RESULTS: We analyzed the acute care course of these patients from the time of injury through admission, resuscitation, and ICU stay, as well as their rehabilitation follow-up results for < or = 1 yr. These two groups did not differ significantly regarding admission intracranial computed tomography diagnosis, admission Glasgow motor score, percentage of monitored time that intracranial pressure was > or = 20 mm Hg, or frequency of initial intracranial pressure > or = 20 mm Hg. In group 2, more patients were aged > 40 yrs (24% vs. 15% in group 1) or had admission hypotension (33% in group 2 vs. 25% in group 1). Multivariate regression analysis showed that ICU stay was significantly longer in group 1 (mean 7.76 days) than group 2 (mean 4.84 days; p < .001). The occurrence of pneumonia was significantly higher in group 1 (29% vs. 15%, p < .001). There was a tendency toward a higher occurrence of sepsis in group 1, but this difference did not reach statistical significance (11% vs. 7%, p = .08). The final Glasgow Outcome Scale scores for the two groups were not significantly different in those survivors with good and moderate outcomes. Although there were more deaths in group 2 (39% vs. 24%, p < .001), there were more vegetative or severely disabled survivors in group 1 (8% vs. 4% and 21% vs. 13%, respectively). CONCLUSIONS: Our findings suggest that early, routine, long-term use of neuromuscular blocking agents in patients with severe head injuries to manage intracranial pressure does not improve overall outcome and may actually be detrimental because of the prolongation of their ICU stay and the increased frequency of extracranial complications associated with pharmacologic paralysis. We suggest that routine early management of the head-injured patient in the ICU should be accomplished using sedation alone and that neuromuscular blockade should be generally reserved for patients with intracranial hypertension who require escalation of treatment intensity.
Adolescent↗
The localizing value of asymmetry in pupillary size in severe head injury: relation to lesion type and location.
Reliable Assessment of the probability that a head injury patient harbors a surgical intracranial lesion is critical to both triage and treatment. The authors analyzed data from 608 patients with severe head injuries (Glasgow Coma Scale score, < or = 8) in the Traumatic Coma Data Bank to assess the reliability of pupillary asymmetry in predicting the presence and location of an intracranial mass lesion. Of 210 patients with pupillary asymmetry of > or = 1 mm, 63 (30%) had intracranial mass lesions, 52 (25%) of which were extra-axial in location, 38 (73%) of these located ipsilateral to the larger pupil. Of 51 patients with asymmetry of > or = 3 mm, 22 (43%) had intracranial mass lesions, 18 (35%) of which were extra-axial in location, 14 (64%) of these located ipsilateral to the larger pupil. For both asymmetry categories, strong interactions were found with age and mechanism of injury, the highest incidence of extra-axial lesions occurring in older patients injured other than as occupants of motor vehicles. The authors developed regression equations that provide a graphic means to predict the presence of an intracranial hematoma using data on pupillary asymmetry, age, and mechanism of injury. This predictive model, interpreted in a hospital- and patient-specific fashion, should be of significant use in directing triage, activating diagnostic and therapeutic resources, and evaluating the utility of exploratory trephination.
Accidents, Traffic↗
Effects of droperidol, pentobarbital, and ketamine on myogenic transcranial magnetic motor-evoked responses in humans.
Myogenic motor-evoked responses to transcranial magnetic stimulation of the motor cortex (tcmag-MERs) may become clinically useful for the noninvasive assessment of motor pathway conduction during surgery. However, application is hindered because most anesthetic regimens result in severe depression of tcmag-MER amplitudes. As part of our systematic attempts to identify anesthetic agents and supplements suitable for use during tcmag-MER recording, we studied the effect of bolus doses of pentobarbital (1.5 mg/kg), droperidol (0.07 mg/kg), or ketamine (1 mg/kg), administered intravenously, on compound muscle action potentials to transcranial magnetic stimulation in five healthy volunteers. The doses were chosen to be comparable with doses that might be suitable for supplementation of a nitrous oxide/opioid anesthetic technique. Droperidol administration resulted in sustained amplitude depression of both tibialis and adductor pollicis tc-MERs to 30 +/- 9% and 39 +/- 14% of baseline (P < 0.01). Tcmag-MER amplitude changes after pentobarbital were variable, ranging from no change to substantial amplitude depression (to 20% of baseline) in two subjects. In contrast, ketamine administration did not result in significant amplitude depression. In three subjects, tibialis anterior amplitude increased to 150 to 220% of control values in the first 10 minutes after ketamine. Onset latency was unchanged after any drug. These data indicate that tcmag-MERs are moderately depressed after droperidol and pentobarbital but well preserved after ketamine. Ketamine may be a more suitable supplement to opioid/nitrous oxide anesthesia than droperidol or pentobarbital.
Adult↗
Early failure of short-segment pedicle instrumentation for thoracolumbar fractures. A preliminary report.
Explore the source record for details and available documents.
Bone Screws↗
Cervical conjoined nerve root variant: preoperative imaging and surgical conformation. Case report.
A case of a nerve root anomaly in a patient presenting with cervical radiculopathy is presented. The patient was treated with posterolateral exploration and decompression, resulting in relief of pain and improvement in strength. Both the preoperative contrast-enhanced computerized tomography scan and the magnetic resonance image demonstrated an abnormality behind the C-4 body extending from the right C3-4 neural foramen to the neural foramen at C4-5. At surgery, a dural-encased structure was discovered connecting the C-4 and C-5 nerve roots within the spinal canal. This paper describes the first reported case of a cervical nerve root anomaly of this type, representing a variant of a conjoined nerve root. The occurrence of such nerve root anomalies in the cervical spine should be entered into the differential diagnosis and treatment of cervical radiculopathy.
Aged↗
Intracranial pressure. Monitoring and management.
Monitoring of ICP from the subarachnoid, intraparenchymal, or ventricular spaces can be accomplished easily and reliably. The risks and benefits of each approach should be considered when choosing the monitoring technique. The goal of ICP management is to prevent herniation and to optimize cerebral perfusion. Even transient episodes of post-traumatic cerebral ischemia due to inadequate CPP can quickly nullify all resuscitative efforts. The provision of sufficient CBF is complicated by the varying degree of disruption of pressure autoregulation commonly resulting from head trauma. Post-injury, there is a need to provide a CPP which is elevated to some extent with respect to that sufficient in uninjured brains. This generally requires a CPP of at least 70 mm Hg, which must be accomplished by maintaining an adequate MAP while controlling ICH. Although ICH can generally be controlled using methods commonly employed, the majority of these techniques have potential complications. Additionally, there is increasing evidence that significant variation exists in the pathologic processes driving ICH in individual patients. Therefore, goals such as the desired CPP and conditions such as the relative contribution of edema, cerebral hypervolemia, and ischemia to ICH should optimally be considered in a patient-specific fashion and allow a targeted approach to therapy.
Barbiturates↗
Early and late systemic hypotension as a frequent and fundamental source of cerebral ischemia following severe brain injury in the Traumatic Coma Data Bank.
The outcome from severe head injury (GCS < or = 8 mmHg) was prospectively studied in patients from the Traumatic Coma Data Bank. We investigated the impact on outcome of hypotension (SBP < 90 mmHg) occurring from injury through resuscitation (early hypotension; N = 717) or in the Intensive Care Unit [ICU] (late hypotension; N = 493). Early hypotension occurred in 248 patients (34.6%) and was associated with a doubling of mortality (55% vs. 27%). If shock was present on admission, the mortality was 65%. These effects were independent of age, admission GCS motor score, presence of hypoxia, or associated severe extracranial trauma, suggesting that the influence of multiple system trauma in head injured patients is primarily due to associated hypotension. Late hypotension occurred in 156 of 493 patients (32%) and was the only hypotensive episode in 117 (24%). For 117 patients whose only hypotensive episode occurred in the ICU, 66% either died or were vegetative survivors, compared to 17% of patients who never suffered an hypotensive episode. Logistic regression modelling suggested that early and late shock were the most powerful independent predictors of mortality in this group of patients. These data demonstrate that hypotension is a common and devastating secondary brain insult in severe head injury patients, occurring not only during transport and resuscitation but also "right under our noses" in the ICU. We suggest that vigorous attention to eliminate or minimize such insults has the potential of markedly improving outcome from severe head injury.
Adolescent↗
Vertebral collapse with quadraparesis due to metastatic gliobla multiforme: case report and review of the literature.
A case is reported of a patient rendered quadraparetic following collapse of a cervical vertebra due to neoplastic invasion by metastatic glioblastoma multiforme. The case is discussed in light of a review of the world literature regarding the clinical incidence and significance of metastasis of glial tumors. It is recommended that all patients with high grade glial tumors who complain of back pain be evaluated with plain radiographs and MRI of the spine or 99Tc bone scan. The management of pathologic spine fractures from metastatic glial tumors with accompanying spinal instability or spinal cord compression due to intracanalicular bone should aim for immediate surgical decompression and stabilization followed by involved field irradiation.
Adult↗
The role of secondary brain injury in determining outcome from severe head injury.
As triage and resuscitation protocols evolve, it is critical to determine the major extracranial variables influencing outcome in the setting of severe head injury. We prospectively studied the outcome from severe head injury (GCS score < or = 8) in 717 cases in the Traumatic Coma Data Bank. We investigated the impact on outcome of hypotension (SBP < 90 mm Hg) and hypoxia (Pao2 < or = 60 mm Hg or apnea or cyanosis in the field) as secondary brain insults, occurring from injury through resuscitation. Hypoxia and hypotension were independently associated with significant increases in morbidity and mortality from severe head injury. Hypotension was profoundly detrimental, occurring in 34.6% of these patients and associated with a 150% increase in mortality. The increased morbidity and mortality related to severe trauma to an extracranial organ system appeared primarily attributable to associated hypotension. Improvements in trauma care delivery over the past decade have not markedly altered the adverse influence of hypotension. Hypoxia and hypotension are common and detrimental secondary brain insults. Hypotension, particularly, is a major determinant of outcome from severe head injury. Resuscitation protocols for brain injured patients should assiduously avoid hypovolemic shock on an absolute basis.
Abbreviated Injury Scale↗
Head injury and shock.
Explore the source record for details and available documents.
Clinical Trials as Topic↗