Module - 5 - Neurological Emergencies Flashcards

Question

25. You are transporting a normotensive patient, who is presenting with a history of head injury and complaining of extreme thirst. Your assessment reveals he is excreting large amounts of diluted urine, sunken appearance to the eyes, dry mouth, and tachycardia is noted. The initial treatment of the patient would be? A. Restrict fluids B. Administer Sandostatin C. Aggressive fluid replacement and vasopressin D. Administer anti-thyroid medication

Answer 1

25. C: Diabetes insipidus (DI) is a condition characterized by excessive thirst and excretion of large amounts of severely diluted urine, with reduction of fluid intake having no effect on the latter. There are several different types of DI, each with a different cause. The most common type in humans is central DI, caused by a deficiency of arginine vasopressin (AVP), also known as antidiuretic hormone (ADH). The regulation of urine production occurs in the hypothalamus, which produces ADH. The hormone is stored for later release in the posterior lobe of the pituitary gland. The cause of central diabetes insipidus is usually damage to the pituitary gland or hypothalamus, most commonly due to surgery, a tumor, illness (such as meningitis), inflammation or a head injury. In some cases the cause is unknown. This damage disrupts the normal production, storage, and release of ADH.

Answer 2

26. B: Cushing’s triad is defined as a widening pulse pressure (rising systolic, declining diastolic), change in respiratory pattern (irregular respirations), and bradycardia. It is sign of increased ICP, and it occurs as a result of the Cushing reflex. The body’s compensatory mechanism and response to decreased cardiac output is to stimulate the sympathetic nervous system. This will cause vasoconstriction and results in a rise in the diastolic pressure, causing a narrowed pulse pressure. A narrow pulse pressure, which is the difference between the systolic and the diastolic, is an early indication of shock. Look for hypovolemia or decreased cardiac output. A narrowing pulse pressure in shock is consistent with hypovolemic and cardiogenic causes. Septic shock will cause a widened pulse pressure. One way to differentiate shock in your patients is to look at the pulse pressure. A narrowing pulse pressure associated with hypovolemia would be hypovolemic. A narrowing pulse pressure associated with volume overload would be cardiogenic. A widening pulse pressure associated with hypovolemia would be septic. 27. D: The classic symptoms include

Answer 3

27. D: The classic symptoms include transient loss of consciousness, recovery with a lucid interval during which the patient’s neurologic status returns to normal, and the secondary onset of headache and a decreasing level of consciousness. In children, bradycardia and early papilledema (optic disc swelling) may be the only warning signs. Epidural hematomas are usually caused by tears in arteries, resulting in a buildup of blood between the dura and the skull. The dura mater also covers the spine, so epidural bleeds may also occur in the spinal column. Often due to trauma, the condition is potentially deadly because the buildup of blood may increase pressure in the intracranial space and compress delicate brain tissue. Epidural hematoma commonly results from a blow to the side of the head. The pterion region which overlies the middle meningeal artery is relatively weak and prone to injury. Epidural hematomas are classified as acute or subacute. An acute epidural hematoma that is arterial in origin generally produces symptoms within a few hours. Subacute epidural hematomas are venous in origin and take a longer time to produce symptoms. These hematomas are associated with linear skull fractures in 90% of patients. Hemorrhages commonly result from acceleration-deceleration trauma and transverse forces (10% of epidural bleeds may be venous). Venous epidural bleeds are usually due to shearing injury from rotational or linear forces, caused when tissues of different densities slide over one another. Subdural hematoma is a collection of blood within the outermost meningeal layer, between the dura mater, which adheres to the skull, and the arachnoid mater enveloping the brain. Usually resulting from tears in veins that cross the subdural space, subdural hemorrhages may cause an increase in ICP, which can cause compression of and damage to delicate brain tissue. Subdural hematomas are classified as acute (within 24 hours), subacute (between 2-10 days), and chronic (after 2 weeks). Subdural hematomas are often life-threatening when acute, but chronic subdural hematomas are usually not deadly if treated. Elderly patients may have larger subdural hematomas, with slowly developing symptoms because they have larger potential subdural spaces as a result of cerebral atrophy. Subdural hematomas generally occur in children less than two years of age. Signs and symptoms include a bulging fontanelle and a large head (because of separation of the sutures) and retinal hemorrhages as a result of increased ICP.

Answer 4

28. A: Subarachnoid hemorrhage is bleeding into the subarachnoid space, the area between the arachnoid membrane and the pia mater surrounding the brain. This may occur spontaneously, usually from a ruptured cerebral aneurysm, or may result from head injury. Signs and symptoms can include a severe headache with a rapid onset (“thunderclap headache,” which is described as the worst ever), vomiting, neck stiffness (Brudzinski’s sign—severe neck stiffness causes a patient’s hips and knees to flex when the neck is flexed.), confusion, or a lowered level of consciousness, and sometimes seizures (1 in 14 patients). Intracerebral hemorrhage is a subtype of intracranial hemorrhage, which occurs within the brain tissue and not outside of it. Most intracerebral hematomas are found the frontal and temporal lobes, usually very deep, and are associated with necrosis and hemorrhage. The clinical picture may vary from no neurologic defect to deep coma. Intracerebral bleeds are the second most common cause of stroke, accounting for 30-60% of hospital admissions for stroke. High blood pressure raises the risk of spontaneous intracerebral hemorrhage by two to six times. More common in adults than in children, intraparenchymal bleeds due to trauma are usually due to penetrating head trauma but can also be due to depressed skull fractures; some may experience intense headaches. They may also go in to a coma before the bleed is noticed. A hit in the head or a fracture in the skull may also cause this bleed, acceleration-deceleration trauma, rupture of an aneurysm or arteriovenous malformation (AVM), and bleeding within a tumor.

Answer 5

29. B: The Babinski’s sign can indicate upper motor neuron lesion constituting damage to the corticospinal tract (central nervous system). A normal Babinski’s reflex is plantar flexor (toes curl in “claw”) and an abnormal reflex is plantar extensor (toes fan out). In infants, the primitive reflexes are still present and will show an extensor reflex response. This happens because the corticospinal pathways that run from the brain down the spinal cord are not fully myelinated at this age, so the reflex is not inhibited by the cerebral cortex. The extensor response disappears and gives way to the flexor response around 12-24 months of age.

Answer 6

30. D: Seizure types are organized according to whether the source of the seizure within the brain is localized (partial or focal onset seizures) or distributed (generalized seizures). Partial seizures are further divided on the extent to which consciousness is affected (simple partial seizures and complex partial seizures). If consciousness is unaffected, then it is a simple partial seizure; otherwise, it is a complex partial seizure. A partial seizure may spread within the brain—a process known as secondary generalization. Generalized seizures are divided according to the effect on the body, but all involve loss of consciousness. These include absence, myoclonic, clonic, tonic, tonic-clonic, and atonic seizures. A mixed seizure is defined as the existence of both generalized and partial seizures in the same patient. Generalized epilepsy leading to status epilepticus is mostly seen in the acute state in one of the two situations: with generalized encephalopathy, including that immediately following trauma, and in patients who are known epileptics, who have reduced drug intake, and whose blood levels have fallen below therapeutic concentrations. Use a benzodiazepine as the first-line therapy. Seizure management requires a risk benefit analysis that balances the patient’s needs with the urgency of the situation. Lorazepam is the preferred first-line agent for seizure control due to its long-lasting anticonvulsant properties. Diazepam is equally effective but requires that a concomitant, long-acting antiseizure medication be administered, such as Dilantin. When the IV access is unavailable, alternate routes such as IM injections of Midazolam, rectal solutions of Diazepam, and IM Fosphenytoin should be considered; of the three, IM Midazolam is probably the fastest and easiest to use. Alternative agents that have been used to manage seizure activity include Phenobarbital, Lidocaine, etomidate, propofol, and Paraldehyde.

Answer 7

31. C: The facial nerve is the seventh (VII) of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity. It also supplies preganglionic parasympathetic fibers to several head and neck ganglia. Patients may suffer from acute facial nerve paralysis, which is usually manifested by facial paralysis. Bell’s palsy is one type of idiopathic acute facial nerve paralysis, which is more accurately described as a multiple cranial nerve ganglionitis that involves the facial nerve, and most likely results from viral infection and also sometimes as a result of Lyme disease. Voluntary facial movements, such as wrinkling the brow, showing teeth, frowning, closing the eyes tightly (inability to do so is called lagophthalmos), pursing the lips, and puffing out the cheeks, all test the facial nerve.

Answer 8

32. B: Cranial nerve III, which is the oculomotor nerve, innervates five intrinsic eye muscles: levator palpebrae superioris, superior rectus, medial rectus, inferior rectus, and inferior oblique, which collectively perform most eye movements. It also sends parasympathetic efferents (via the ciliary ganglion) to the muscles controlling pupillary constriction and accommodation. The motor fibers originate in the oculomotor nuclei of the midbrain.

Answer 9

33. D: Cranial nerve VI, which is the accessory nerve (spinal accessory nerve), originates from neurons in the medulla and in the cervical spinal cord. It has a cranial root, which joins the vagus (cranial nerve X) nerve and sends motor fibers to the muscles of the larynx, and a spinal root, which sends motor fibers to the trapezius and the sternocleidomastoid muscles. Damage to the nerve produces weakness in head rotation and shoulder elevation.

Answer 10

34. A: Guillain-Barre syndrome is an acute inflammatory demyelinating polyneuropathy (AIDP), an autoimmune disorder affecting the peripheral nervous system, usually triggered by an acute infectious process. It is frequently severe and usually exhibits as an ascending paralysis noted by weakness in the legs that spreads to the upper limbs and the face, along with complete loss of deep tendon reflexes. With prompt treatment by plasmapheresis or intravenous immunoglobulins and supportive care, majority of patients will regain full functional capacity. Myasthenia gravis is an autoimmune neuromuscular disease, leading to fluctuating muscle weakness and fatiguability. It is an autoimmune disorder, in which weakness is caused by circulating antibodies that block acetylcholine receptors at the postsynaptic neuromuscular junction, inhibiting the stimulative effect of the neurotransmitter acetylcholine. Myasthenia is treated medically with cholinesterase inhibitors or immunosuppressants, and, in selected cases, thymectomy. Symptoms, which vary in type and severity, may include asymmetrical ptosis (a drooping of one or both eyelids), diplopia (double vision) due to weakness of the muscles that control eye movements, an unstable or waddling gait, weakness in arms, hands, fingers, legs, and neck, a change in facial expression, dysphagia (difficulty in swallowing), shortness of breath and dysarthria (impaired speech, often nasal due to weakness of the velar muscles). In myasthenic crisis a paralysis of the respiratory muscles occurs, necessitating assisted ventilation to sustain life. In patients whose respiratory muscles are already weak, crises may be triggered by infection, fever, an adverse reaction to medication, or emotional stress. Diagnostic testing is done by injecting the drug edrophonium chloride (Tensilon, Reversol) or neostigmine (Prostigmin) into a vein and watching for rapid improvement of strength, usually of eye muscles. In patients with myasthenia gravis, involving the eye muscles, Edrophonium Chloride will briefly relieve eye muscle weakness. Improvement in strength of speech may also be considered a positive test.

Answer 11

36. C: Central Cord syndrome is a type of injury that usually results from hyperextension and is characterized by a disproportionally greater motor impairment of the upper than the lower extremities with variable sensory loss below the level of injury. Sacral sparing typically occurs. Two very important determinants of an incomplete, as opposed to a complete, lesion of the spinal cord are preservation of voluntary rectal sphincter tone and perianal sensation (“sacral sparing”). To check for voluntary rectal sphincter tone, insert a gloved finger in the rectum and request the patient, if cooperative, to squeeze down as if attempting to prevent movement of the bowels. If able to do so, there is substantial indication of an incomplete, as opposed to a complete, spinal cord injury, i.e., some spinal neural pathways are intact.

Answer 12

37. A: The presence of the plantar extensor reflex (toes fan upward) in an adult patient can indicate damage to the nerve pathways connecting the spinal cord and brain. It is wrong to say that the Babinski’s reflex is positive or negative; it is present (plantar extensor reflex—toes fan upward which is bad) or absent (plantar flexor response—toes curl downward which is good).

Answer 13

38. C: The absence of doll’s eye sign indicates injury to the midbrain or pons, involving cranial nerves III and VI. It typically accompanies coma caused by lesions of the cerebellum and brain stem. This sign usually can’t be relied upon in a conscious patient because he can control eye movements voluntarily. Absent doll’s eye sign is necessary for a diagnosis of brain death.

Answer 14

An indicator of brainstem dysfunction, the absence of the doll’s eye sign is detected by rapid, gentle turning of the patient’s head from side to side. The eyes remain fixed in midposition, instead of the normal response of moving laterally toward the side opposite the direction the head is turned. Lopez, Orchid Lee (2011-02-15). Back To Basics: Critical Care Transport Certification Review (p. 211). Xlibris. Kindle Edition.

Answer 15

39. B: Clinical evaluation of brain death can be performed with the application of the oculovestibular reflex (cold-caloric exam). With head on bed at 30 degrees, instill 50 mL of iced water into ear canal. A normal response (presence of oculovestibular reflex) is tonic deviation of the eyes toward the irrigated ear.

Answer 16

40. C: Mydriasis is an excessive dilation of the pupil due to disease, trauma, or the use of drugs. A mydriatic pupil will remain excessively large even in a bright environment and is sometimes referred to as “blown pupil.” Pupillary dilation (mydriasis) indicates unopposed sympathetic activity due to impaired parasympathetic axons. This may reflect compression or distortion of the oculomotor nerve (CN III) by either primary injury or herniation. Mydriasis also may be an effect of adrenergic stimuli, such as epinephrine, anticholinergics, cocaine, PCP, and drug withdrawal. The classic fixed and dilated “blown pupil” is a unilateral phenomenon that may occur when a rapidly expanding intracranial mass, including blood from a hemorrhage, is compressing cranial nerve III. It may also represent herniation of the uncus of the temporal lobe. The opposite, constriction of the pupil, is referred to as miosis.

Answer 17

41. B: A basilar skull fracture (or basal skull fracture) is a fracture of the base of the skull, typically involving the temporal bone, occipital bone, sphenoid bone, and/or ethmoid bone. This type of fracture is rare, occurring as the only fracture in just 4% of severe head injury patients. Such fractures can cause tears in the membranes surrounding the brain, or meninges, with resultant leakage of the cerebrospinal fluid (CSF). The leaking fluid may accumulate in the middle ear space and dribble out through a perforated eardrum (CSF otorrhea) or into the nasopharynx via the eustachian tube, causing a salty taste. CSF may also drip from the nose (CSF rhinorrhea) in fractures of the anterior skull base, yielding a halo sign. Clinical signs include Battle’s sign, which is ecchymosis of the mastoid process of the temporal bone and Raccoon eyes is periorbital ecchymosis (“black eyes”).

Answer 18

42. A: Epidural hematomas are usually caused by tears in arteries, resulting in a buildup of blood between the dura and the skull. The middle meningeal artery runs in a groove on the inside of the cranium beneath the pterion, which is vulnerable to injury at this point, where the skull is thin. A blow or fracture of the temporal bone is often the cause of a rupture of the middle meningeal artery, which may cause an epidural hematoma.

Answer 19

43. B: The opposite of mydriasis (dilated pupil) is constriction of the pupil and is referred to as miosis when less than or equal to two millimeters. This is a normal response to an increase in light but can also be associated with certain pathological conditions, microwave radiation exposure, and certain drugs, especially opioids.

Answer 20

44. C: Normal MAP is 80-100 mmHg.

Answer 21

45. B: The best treatment for hydrocephalus is the placement of an extracranial shunt from the ventricles to an outside absorptive surface such as ventriculoperitoneal, ventriculoatrial, or ventriculopleural. Shunts usually consist of three parts: a. Proximal end that is radiopaque and is placed into the ventricle. This end has multiple small perforations. b. Valve—this allows for unidirectional flow. Can adjust various opening pressures. Usually has a reservoir that allows for checking shunt pressure and sampling CSF. c. Distal end that is placed into the peritoneum or another absorptive surface by tracking the tubing subcutaneously.

Answer 22

46. B: Brown-Séquard syndrome is a type of injury that usually results from a penetrating injury which has damaged one side of the spinal cord and is characterized by motor loss on the same side and sensory loss on the opposite side of the injury. Spinal cord injury can be classified in two main forms: complete and incomplete. A complete injury is defined as one in which there is complete disruption of continuity of all spinal pathways at one or more levels of the spinal cord. The result is absent motor function, sensory and pressured (touch) sensation and position and vibratory perception to all body areas enervated by the spinal cord tissue below the level of disruption. Incomplete spinal cord injury can be defined as one in which there is a variable degree of loss of function secondary to partial disruption of the spinal cord (some pathways of neurological function are intact, some are disrupted either permanently or transiently).

Answer 23

47. A: Anterior cord syndrome is a type injury that usually results from hyperflexion and is characterized by variable loss of motor and sensory function below the level of injury. However, posterior column function is maintained. Clinically this person will present with a variable degree, perhaps even complete, of motor and sensory loss below the level of injury to the spinal cord, but the capacity to perceive light touch and position sense distal to the injury is maintained. Refer to the table in question 20 for review of spinal cord syndromes.

Answer 24

48. A: Meningitis is inflammation of the meninges, which are the protective coverings that are present over the brain and the spinal cord. This inflammation can be either bacterial or viral in nature. Some of the common symptoms that the patient presents with include headache and neck stiffness. This is a serious and possibly fatal condition, as the inflammation of the meninges can easily spread to the brain and the spinal cord, thus, causing life-threatening complications. One of the important bacterial meningitis precautions is to see to it that the patient wears a face mask at all times. This is of paramount importance because bacterial meningitis is contagious in nature, and it is a droplet infection. H. influenzae and N meningitis may be transmitted by droplets generated during coughing, sneezing, talking, or procedures, such as intubation and bronchoscopy. Droplet precautions should therefore be used whenever there is a clinical suspicion of infection with one of these pathogens. Traditional systems of isolation precautions have relied on an understanding of the mechanisms by which disease can be spread and have focused the use of protective barrier equipment, such as gloves, gowns, masks, and protective eyewear in order to interrupt transmission and to break the chain of infection.

Answer 25

49. A: Abnormal posturing is an involuntary flexion or extension of the arms and legs, indicating severe brain injury. It occurs when one set of muscles becomes incapacitated, while the opposing set is not, and an external stimulus, such as pain, causes the working set of muscles to contract. Posturing can be caused by conditions that lead to large increases in ICP. Such conditions include traumatic brain injury, stroke, intracranial hemorrhage, brain tumors, and encephalopathy. Posturing due to stroke usually only occurs on one side of the body and may also be referred to as spastic hemiplegia. Progression from decorticate posturing to decerebrate posturing is often indicative of uncal (transtentorial) or tonsilar brain herniation. Refer to the table for review of abnormal posturing. Lopez, Orchid Lee (2011-02-15). Back To Basics: Critical Care Transport Certification Review (pp. 214-215). Xlibris. Kindle Edition.

Answer 26

50. B: The middle cerebral artery (MCA) is one of the three major paired arteries that supplies blood to the cerebrum. The left and right MCAs rise from trifurcations of the internal carotid arteries and thus are connected to the anterior cerebral arteries and the posterior communicating arteries, which connect to the posterior cerebral arteries. The MCAs are not considered a part of the Circle of Willis. Occlusion/damage of the middle cerebral artery results in middle cerebral artery syndrome, potentially showing the following: paralysis (plegia) or weakness (paresis) of the contralateral face and arm (faciobrachial); sensory loss of the contralateral face and arm; damage to the dominant hemisphere (usually the left hemisphere since most individuals are right-handed) results in aphasia (Broca’s or Wernicke’s); large MCA infarcts often have deviation conjugée (a gaze preference toward the side of the lesion), especially during the acute period. Lopez, Orchid Lee (2011-02-15). Back To Basics: Critical Care Transport Certification Review (p. 215). Xlibris. Kindle Edition.

Answer 27

MAP = [(DBP × 2) + SBP] divided by 3 Normal 80-100 CPP = MAP − ICP 70-90 ICP 0-10

Answer 28

60-140 mmHg * As MAP *increases*, cerebral arterial blood vessels *constrict*, preventing the increase in blood volume and flow that would normally occur. * If the MAP *decreases*, the cerebral arteries *dilate*, increasing cerebral blood flow.

Answer 29

**A** - Acidosis, AMI, alcohol **E** - Epilepsy, electrolytes **I** - Infection **O** - OD, Oxygen **U** - Uremia **T** - Trauma **I** - Insulin **P** - Psychosis **S** - Sepsis, Shock

Answer 30

tachypnea, normal heart rate, and hypotension.

Answer 31

the presence of a subarachnoid hemorrhage as well as meningitis.

Answer 32

consists of bruising over the mastoid process as a result of extravasation of blood along the path of the posterior auricular artery and can indicate basilar skull fracture.

Answer 33

* also known as vestibulo-ocular reflex or oculovestibular reflex is a reflex movement during head movement by producing an eye movement in the direction opposite to head movement. * The absence of the doll’s eye’s reflex (eyes remain in midposition when is being moved from side to side) can indicate injury to the midbrain or pons, cranial nerves III and VI.

Answer 34

brain herniation.

Answer 35

neurogenic shock ## Footnote tachypnea, hypotension, and a normal heart rate but can also be present with bradydysrhythmias because of loss of sympathetic tone secondary to the spinal cord injury.

Answer 36

Is the innermost part of the temporal lobe, it can be compressed so that it goes by the tentorium and places pressure on the brain. * The uncus can compress the *third cranial nerve*, which can affect the parasympathetic input to the eye on the side of the affected nerve, **causing the pupil on the affected side** to dilate and fail to constrict in response to light as it should.

Answer 37

I Olfactory Smell II Optic Vision III Oculomotor Eye movement; origin midbrain IV Trochlear Eye movement; origin midbrain V Trigeminal Mastication; origin pons VI Abducens Eye movement; origin pons VII Facial Facial expression; origin pons VIII Vestibulocochlear (auditory) Hearing and balance IX Glossopharyngeal Taste; origin medulla X Vagus Swallowing; origin medulla XI Accessory Sternocleidomastoid and trapezius muscles; ability to move head and shrug shoulders XII Hypoglossal Muscle of tongue, speech articulation and swallowing; origin medulla

Answer 38

I Olfactory Smell One Nose

Answer 39

II Optic Vision TWO EYES

Answer 40

III Oculomotor Eye movement; origin midbrain

Answer 41

IV Trochlear Eye movement; origin midbrain ## Footnote

Answer 42

V Trigeminal Mastication; origin pons ## Footnote

Answer 43

VI Abducens Eye movement; origin pons ## Footnote

Answer 44

VII Facial Facial expression; origin pons ## Footnote

Answer 45

VIII Vestibulocochlear (auditory) Hearing and balance ## Footnote

Answer 46

IX Glossopharyngeal Taste; origin medulla ## Footnote

Answer 47

X Vagus Swallowing; origin medulla ## Footnote

Answer 48

XI Accessory Sternocleidomastoid and trapezius muscles; ability to move head and shrug shoulders ## Footnote

Answer 49

XII Hypoglossal Muscle of tongue, speech articulation and swallowing; origin medulla

Answer 50

runs in a groove on the inside of the cranium beneath the pterion, which is vulnerable to injury at this point, where the skull is thin. * A blow or fracture of the temporal bone is often the cause of a rupture of the middle meningeal artery, which may cause an epidural hematoma (occurs between the skull and the dura). * There is often significant “mass effect” with compression of the ipslateral lateral ventricle and dilatation of the opposite lateral ventricle due to obstruction of the foramen of Monro. * Emergency treatment requires decompression of the hematoma, usually by craniotomy.

Answer 51

* (usually caused by tears in the artery) * Bleeding occurs between the skull and dura mater. * “Epi” meaning above the dura. * Brief loss of consciousness, ***lucid interval into deteriorating level of consciousness.***

Answer 52

* (usually caused by tears in the veins) * Bleeding occurs between the dura mater and the arachnoid mater. “Sub” meaning below the dura. * The space enlarges as the brain atrophies, so more common in the elderly patient. * Can be acute or chronic. * Changes in mentation can occur several weeks after injury.

Answer 53

* a craniocerebral erosion or leptomeningeal cyst due to the usual development of a cystic mass filled with cerebral spinal fluid * is a rare complication of head injury usually associated with linear skull fractures of the parietal bone in children below three years of age.

Answer 54

Linear * Are breaks in the bone, usually from blunt force trauma, that transverse the full thickness of the skull from the outer to inner table, are usually fairly straight and involve no displacement of the bone. * Usually of little clinical significance unless they are parallel in close proximity or transverse a suture, or they involve a venous sinus groove or vascular channel.

Answer 55

Compressed (depressed) * Usually resulting from blunt force trauma, such as getting struck with object, getting kicked in the head. * Carry a high risk of increased pressure on the brain, crushing the delicate tissue.

Answer 56

Distatic * Occur when the fracture line transverses one or more sutures of the skull, causing a widening of the suture. * Usually seen in infants and children.

Answer 57

Basilar * Breaks in bones at the base of the skull, require more force to cause than cranial vault fractures. * Blood in the sinuses; a clear fluid called cerebrospinal fluid (CSF) leaking from the nose or ears; * raccoon eyes (bruising of the orbits of the eyes that result from blood collecting there as it leaks from the fracture site); * Battle’s sign (caused when blood collects behind the ears and causes bruising).

Answer 58

(bruising of the orbits of the eyes that result from blood collecting there as it leaks from the fracture site); seen with basilar skull fracture

Answer 59

is the triad of : * widening pulse pressure (rising systolic, declining diastolic), * change in respiratory pattern (irregular respirations), * bradycardia. It is a sign of increased ICP Normal ICP is 0-10 mmHg

Answer 60

* Interruption of sympathetic outflow below the level of the injury results in loss of autoregulation, a decrease in vascular tone, and an inability of the heart to increase its intrinsic rate. With passive vasodilation and a normal bradycardic state, the patient becomes hypotensive. * The sympathetic block or loss of sympathetic tone produces poikilothermy. In this state, the patient loses the ability to vasodilate and sweat in hot environments and the ability to vasoconstrict and shiver in cold environments. * The classic picture of neurogenic shock presents with the absence of tachycardia.

Answer 61

T6 spinal cord level Acute AD is a reaction of the autonomic (involuntary) nervous system to overstimulation. Catheterization of the bladder or relief of a blocked urinary catheter tube may resolve the problem.

Answer 62

is the most common spinal cord injury (SCI) syndrome. * This syndrome is unlike a complete lesion and causes loss of all sensation and movement below the level of the injury. * It is characterized by disproportionately greater motor impairment in upper compared to lower extremities and variable degree of sensory loss below the level of injury. * Most often occurs after hyperextension injury. **Remember “you can dance, but you can't clap."**

Answer 63

* Any presentation of spinal injury that is an incomplete lesion, so long as it is characterized by features of * a motor loss and numbness to touch and vibration on the same side of the spinal injury * and loss of pain and temperature sensation on the opposite side. * Most often occurs from a penetrating injury that has damaged one side of the spinal cord.

Answer 64

* Blood supply to the anterior portion of the spinal cord is interrupted, causing a complete motor paralysis below the level of the lesion due to interruption of the corticospinal tract. * Loss of pain and temperature sensation at and below the level of the lesion due to interruption of the spinothalamic tract. * Retained proprioception and vibratory sensation due to intact dorsal columns. * Most often occurs after hyperflexion

Answer 65

extracellular volume depletion and cerebral edema. * These can all result in dangerous increases in ICP. * Hypertonic saline can help avoid the negative effects of hyponatremia by increasing serum sodium levels in the acute phase of head trauma care. * Maintaining serum sodium levels of 145-155 mmol/L is likely to achieve this goal, but no higher as it may cause renal/cardiac/and pulmonary problems.

Answer 66

the presence of air or gas within the cranial cavity. * Usually associated with disruption of the skull: after head and facial trauma, tumors of the skull base, after neurosurgery, or with scuba diving (rare). * The CT scan of patients with a tension pneumocephalus typically show air that compresses the frontal lobes of the brain, which results in a tented appearance of the brain in the skull known as the Mount Fuji sign. * Symptoms vary but Headache is nearly always present.

Answer 67

a deficiency of arginine vasopressin (AVP), also known as antidiuretic hormone (ADH). * The regulation of urine production occurs in the hypothalamus, which produces ADH. * The hormone is stored for later release in the posterior lobe of the pituitary gland. * The cause of central diabetes insipidus is usually damage to the pituitary gland or hypothalamus, most commonly due to surgery, a tumor, illness (such as meningitis), inflammation or a head injury.

Answer 68

A narrowing pulse pressure in shock is consistent with hypovolemic and cardiogenic causes. Septic shock will cause a widened pulse pressure. * A narrowing pulse pressure associated with hypovolemia would be hypovolemic. * A *narrowing* pulse pressure associated with volume overload would be *cardiogenic*. * A **widening** pulse pressure associated with hypovolemia would be **septic**.

Answer 69

An **acute epidural hematoma** that is ***arterial*** in origin generally produces symptoms within a few hours. **Subacute epidural hematomas** are ***venous*** in origin and take a longer time to produce symptoms. * These hematomas are associated with linear skull fractures in 90% of patients. * Hemorrhages commonly result from acceleration-deceleration trauma and transverse forces (10% of epidural bleeds may be venous). * Venous epidural bleeds are usually due to shearing injury from rotational or linear forces, caused when tissues of different densities slide over one another.

Answer 70

is a collection of blood within the outermost meningeal layer, between the dura mater, which adheres to the skull, and the arachnoid mater enveloping the brain. Subdural hematomas are classified as: * acute (within 24 hours) * subacute (between 2-10 days) * chronic (after 2 weeks). Subdural hematomas are often life-threatening when acute, but chronic subdural hematomas are usually not deadly if treated.

Answer 71

is bleeding into the subarachnoid space, the area between the arachnoid membrane and the pia mater surrounding the brain. * This may occur spontaneously, usually from a ruptured cerebral aneurysm, or may result from head injury. * Signs and symptoms can include a severe headache with a rapid onset vomiting, neck stiffness (Brudzinski’s sign), confusion, or a lowered level of consciousness, and sometimes seizures (1 in 14 patients).

Answer 72

Intracerebral hemorrhage is a subtype of intracranial hemorrhage, which occurs within the brain tissue and not outside of it. * Most intracerebral hematomas are found the frontal and temporal lobes, usually very deep, and are associated with necrosis and hemorrhage. * Intracerebral bleeds are the second most common cause of stroke, accounting for 30-60% of hospital admissions for stroke. * High blood pressure raises the risk of spontaneous intracerebral hemorrhage by two to six times. * More common in adults than in children, intraparenchymal bleeds due to trauma are usually due to penetrating head trauma but can also be due to depressed skull fractures; some may experience intense headaches. They may also go in to a coma before the bleed is noticed. A hit in the head or a fracture in the skull may also cause this bleed, acceleration-deceleration trauma, rupture of an aneurysm or arteriovenous malformation (AVM), and bleeding within a tumor.

Answer 73

is plantar flexor (toes curl in “claw”) and an abnormal reflex is plantar extensor (toes fan out). * In infants, the primitive reflexes are still present and will show an extensor reflex response. This happens because the corticospinal pathways that run from the brain down the spinal cord are not fully myelinated at this age, so the reflex is not inhibited by the cerebral cortex. * The extensor response disappears and gives way to the flexor response around 12-24 months of age.

Answer 74

Anterior cord syndrome * is characterized by variable loss of motor and sensory function below the level of injury. However, posterior column function is maintained. * Clinically this person will present with a variable degree, perhaps even complete, of motor and sensory loss below the level of injury to the spinal cord, but the capacity to perceive light touch and position sense distal to the injury is maintained. * Chin to chest

Answer 75

Central Cord syndrome * is a type of injury that usually results from hyperextension * is characterized by a disproportionally greater motor impairment of the upper than the lower extremities with variable sensory loss below the level of injury. * Sacral sparing typically occurs.

Answer 76

* preservation of voluntary rectal sphincter tone and perianal sensation (“sacral sparing”). * To check for voluntary rectal sphincter tone, insert a gloved finger in the rectum and request the patient, if cooperative, to squeeze down as if attempting to prevent movement of the bowels. * If able to do so, there is substantial indication of an incomplete * opposed to a complete, spinal cord injury, i.e., some spinal neural pathways are intact.

Answer 77

* With head on bed at 30 degrees, instill 50 mL of iced water into ear canal. * A normal response (presence of oculovestibular reflex) is tonic deviation of the eyes toward the irrigated ear.

Answer 78

disease, trauma, or the use of drugs. * will remain excessively large even in a bright environment and is sometimes referred to as “blown pupil.” * indicates **unopposed sympathetic activity** due to impaired parasympathetic axons. This may reflect compression or distortion of the oculomotor nerve (CN III) by either primary injury or herniation. * The classic fixed and dilated “blown pupil” is a unilateral phenomenon that may occur when a rapidly expanding intracranial mass, including blood from a hemorrhage, is compressing cranial nerve III. It may also represent herniation of the uncus of the temporal lobe. * may be an effect of adrenergic stimuli, such as epinephrine, anticholinergics, cocaine, PCP, and drug withdrawal. * The opposite, constriction of the pupil, is referred to as miosis.

Answer 79

is constriction of the pupil when less than or equal to two millimeters. This is a normal response to an increase in light but can also be associated with * certain pathological conditions, * microwave radiation exposure, * certain drugs, especially opioids.

Answer 80

placement of an extracranial shunt from the ventricles to an outside absorptive surface ## Footnote

Answer 81

a sign used to help to diagnose hydrocephalus (accumulation of excess cerebrospinal fluid) and brain abscesses. * Tapping (percussion) the skull near the junction of the frontal, temporal, and parietal bones will produce a stronger resonant sound when either hydrocephalus or a brain abscess is present.

Answer 82

Brown-Séquard syndrome ## Footnote is a type of injury that usually results from a penetrating injury which has damaged one side of the spinal cord and is characterized by motor loss on the same side and sensory loss on the opposite side of the injury.

Answer 83

Posturing due to stroke, usually only occurs on one side of the body.

Answer 84

(also known as flexor posturing) ## Footnote Damage to: Cerebral hemipheres, thalamus, and midbrain Presentation: The elbows, wrists, and fingers flexed, and legs extended and rotated inward.

Answer 85

(also known as extensor posturing) Damage to: lower brainstem, midbrain, and cerebellum Presentation: * The head is arched back (opisthotonos), the arms are extended by the sides, and the legs are extended. * Both the arms and the legs are rotated internally. The body is rigid and teeth are clenched. * A hallmark of decerebrate posturing is extended elbows.

Answer 86

one of the three major paired arteries that supplies blood to the cerebrum. * The left and right MCAs rise from trifurcations of the internal carotid arteries * large MCA infarcts often have deviation conjugée (a gaze preference toward the side of the lesion), especially during the acute period.

Answer 87

also known as expressive asphasia * is characterized by the loss of the ability to produce language (spoken or written). * Expressive aphasia differs from dysarthria, which is characterized by a patient’s inability to properly move the muscles of the tongue and mouth to produce speech.

Answer 88

also known as receptive or sensory aphasia * patients may speak in long sentences that have no meaning, add unnecessary words, and even create new “words,” and have great difficulty in understanding the speech of both themselves and others and are, therefore, often unaware of their mistakes.

Answer 89

is characterized by a patient’s inability to properly move the muscles of the tongue and mouth to produce speech.

Module - 5 - Neurological Emergencies Flashcards

(114 cards)