Bernard Elser, M.D.,     Bernard Elser, M. D., Associate Professor of Medicine, University of Miami School of Medicine; Medical Director, Emergency Room, Jackson Memorial Hospital, Miami, Fla.

Publisher Summary

This chapter discusses the emergency room management for neurological trauma and disease. The emergency room physician is usually the first doctor to see a patient with an obvious or occult neurological or neurosurgical problem. Even though this is also true for most other emergencies, in few other conditions, the initial clinical observations and therapeutic responses to them are as critical in preventing transient deficits from progressing to permanent damage. The birth of emergency medicine as a specialty was brought about by many factors, including the increased utilization by patient and physician alike of the emergency room with its diverse and extensive facilities for all types of real or imagined emergencies. The chapter describes the role of the emergency department physician in evaluating and treating patients with neurological trauma and disease. The chapter also discusses the mechanisms by which central nervous system trauma or disease produces neurological lesions and symptoms. It describes the factors that may complicate the primary lesion.

Objectives

The emergency room physician is usually the first doctor to see a patient with an obvious or occult neurological or neurosurgical problem. Even though this is also true for most other emergencies, in few other conditions are the initial clinical observations and therapeutic responses to them as critical in preventing transient deficits from progressing to permanent damage.

The birth of emergency medicine as a specialty was brought about by many factors, including the increased utilization by patient and physician alike of the emergency room with its diverse and extensive facilities for all types of real or imagined emergencies. As a result, the emergency room physician has developed expertise which cuts across classical specialty lines in order to be able to stabilize, diagnose and treat the myriad problems which may at any time present to the emergency room.

Neurological and neurosurgical emergencies have frequently been a difficult problem for the nonspecialist. The complexity of the nervous system in association with its dominant position in determining the quality of life is probably the major factor in the sense of urgency which is experienced by most emergency room physicians when treating patients with these disorders and is probably also the major reason for the errors, both in commission as well as in omission, which occur in the treatment of these patients. Nevertheless, the large number of elderly patients in our society and the growing complexity of our way of life are rapidly increasing the number of patients who present to emergency rooms with neurological and/or neurosurgical problems. Therefore, emergency room physicians have been forced to develop a growing expertise in assessing, stabilizing and providing for the initial treatment of these patients.

What follows is an attempt to describe the role of the emergency physician and some of the clinical considerations in caring for patients with neurological and neurosurgical problems. The specialist provides the definitive diagnosis and ultimate treatment of these disorders. The initial evaluation, stabilization and disposition of these patients is the function of the emergency room physician.

Rather than review all the well-described classical disorders, their diagnosis and treatment, I thought it would be more appropriate in this setting to select several important concepts within this large area for review and special comment.

Diagnosis

A common presenting problem to the emergency room is the patient in coma, with or without focal neurological signs. The history and physical examination, combined with routine laboratory and radiological studies, are often sufficient to establish a working diagnosis. Another important diagnostic modality is the progression of clinical findings. For example, change in mental state with time is a very important clinical sign. However, the use of poorly defined terms in describing alterations of mental status such as obtunded, stuporous and even coma blunts this important diagnostic tool. These subjective words often prevent accurate description of the progression of a lesion and as a result interfere with the precise determination of the natural history of a disease entity and the results of therapy. A major improvement has been the recent development of the Glasgow Coma Scale (Table 1) which uses a few easily measured parameters of nervous system function to obtain an objective definition of the clinical state of a patient at a single point in time. As a result it is possible to achieve more precise determination of the progression of the disorder and the results of therapy. To be most effective, this evaluation must be initiated as early as possible, in the emergency room, or at the scene of the event.

Understanding the mechanism of brain injury in head trauma is often helpful in estimating the type and anatomical location of a resulting lesion. Additionally, this knowledge permits an understanding of some of the clinical manifestations in circumstances where there is progression of a lesion. To this end, it is useful to classify the head into four compartments: the brain, the extracellular space, the cerebrospinal fluid and the vascular space.

As a result of rapid accelerative and decelerative forces which may occur even in the absence of direct trauma, the brain invariably shifts around inside the head, rocking from side to side and back and forth while the inferior surface slides over the rough orbital surfaces of the base of the skull. As a result one may see contusive injuries, particularly to the frontal and temporal lobes, while the occipital and parietal lobes, surrounded by relatively smooth skull, are less commonly affected by this mechanism. Another important consequence of this motion of the brain within the skull is the torsion and tugging on anchored structures such as the brain stem and superficial blood vessels. These forces may tear veins which bridge the cortex as well as the superior sagittal sinus and may lead to a subdural hemorrhage. Alternately, or concomitantly, there may be compression and dysfunction of the reticular activating system of the brain stem leading to alterations of the mental state.

The brain, encased in a rigid skull, will suffer when any one of the compartments of the brain is increased, either as a result of a hematoma or edema, and impinges upon or displaces another compartment. Initially there are compensatory forces which tend to minimize these effects. For example, a small amount of spinal fluid, blood or extracellular fluid can be squeezed out of the brain and intracranial vault and reduce the intracranial volume when one of the other compartments has increased. Finally, however, as the lesion progresses, compression of brain substance with its displacement into an area of lesser resistance (herniation) may occur. The resulting pressure and ischemic effects on structures such as the third nerve herald this ominous and progressive development. These may occur at variable times following the initial injury and lead to focal or systemic physical signs which, at least initially, may be reversible with adequate therapy.

The...