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- Neuroleptic-induced heat stroke
- Central anticholinergic syndrome
Malignant hyperthermiaInhalational anesthetics: halothane, isoflurane, sevoflurane, and desflurane depolarizing muscle relaxants: succinylcholine Note: it is safe to use thiopental, etomidate, and propofol Presentation: masseter spasm often earliest indicator, then tachypnea, tachycardia, increasing end-tidal carbon dioxide levels and acidosis then hyperthermia and cyanosis, rigidity, rhabdomyolysis Note: can pre-screen with halothane-caffeine contracture test in vitro Treatment: stop offending agent, supportive measures Neuroleptic-induced heat strokeMore in elderly and young / impaired sweating / risk increased by concomitant use of anticholinergics (Cogentin) / can produce seizures Treatment: supportive, rapid cooling, fluids Acute lethal catatoniaPresentation: posturing, waxy flexibility (cerea flexibilitas), hyperactivity preceded by behavioral changes in weeks leading up to motor deficits, which then may progress to hyperthermia, akinesia, and rigidity and death from respiratory and circulatory failure Treatment: electroconvulsive therapy (ECT) Serotonin syndrome Causes: SSRI, amphetamines, cocaine, dextromethorphan, meperidine, TCA, tramadol, MAO Presentation: mental status changes, neuromuscular (tremor, rigidity, seizures + shivering, ataxia, hyperreflexia, myoclonus, ankle clonus), autonomic dysfunction (flushing, labile, HTN, fever, though not as high as NMS, salivation, tachycardia), gastrointestinal dysfunction (nausea, vomiting, diarrhea) Complications: CV collapse, lactic acidosis, multiorgan failure, coma, death are all rare but possible outcomes Labs: WBC, CK, LFT variably elevated Course: recovery in 1-7 days after drug stopped / usually no sequelae Treatment: can give SSRI antagonists, cyproheptadine, chlorpromazine Central anticholinergic syndromePresentation: altered mental status +/- hyperthermia, decreased sweating, mydriasis, dry mouth, and urinary retention Treatment: physostigmine (and supportive measures) CNS injury CVA intracranial hemorrhage venous sinus thrombosis CNS vasculitis Cerebrovascular Accident (CVA, stroke) Carotid/vertebral artery disease (10-15%) Cardiac emboli (25-30%) Intracardiac thrombus or mass MI (anterior wall, septum, akinetic segment), cardiomyopathy, arrhythmias (Afib), cardiac myxoma Valvular rheumatic heart disease, bacterial endocarditis, non-bacterial endocarditis (Libman-Sacks, carcinoma), mitral valve prolapse, prosthetic valve
Primary CNS vasculitis systemic vasculitis (PAN, allergic angiitis), CTD (RA, scleroderma, Sjögren’s), Wegener’s, Behçet’s, GCA, Takayasu’s, lymphomatoid granulomatosis Hypersensitivity vasculitis (serum sickness, drug-induced, cutaneous) Infectious vasculitis (lyme, meningitis, Tb, AIDS, opthalmic zoster, HBV)
Hemoglobinopathies (sickle cell, HbSC) Hyperviscosity syndromes (polycythemia, thrombocytosis, leukocytosis, macroglobulinemia, multiple myeloma) Hypercoagulable states (carcinoma, pregnancy, puerperium, protein C/S deficiency, antiphospholipid antibodies) Drug-related: street drugs (cocaine, amphetamines, lysergic acid, PCP, meth, heroin, pentazocine), alcohol, OCPs Other: lipohyalinosis, fibromuscular dysplasia, arterial dissection, homocystinuria, migraine, moyamoya, other embolic (cholesterol, fat, bone, air) Types of Stroke (see specific syndromes) MCA: contralateral hemiparesis (hemiplegia), hemianesthesia, homonymous hemianopsia dominant aphasia, nondominant apraxia, neglect
Note: only bilateral hemispheric and basilar (RAS) strokes cause loss of consciousness! Aphasia Suggests left hemisphere lesion (most people, even left-handed have language on left) Wernicke’s – from left inferior MCA – fluid but meaningless speech / hemiparesis mild or absent Broca’s – from left superior MCA – impaired speech / hemiparesis, hemisensory loss is common Ddx: brain tumor, hematoma (all kinds), abscess, endocarditis, MS, metabolic (ex. hypoglycemia), neurosyphilis Work-Up: CT without contrast (faster to get and good for r/o herniation, bleed) MRI CBC, glucose, coagulation, lipid, ESR, VDRL EKG and echo Vascular: carotid ultrasound, MRA or CT angiography / transcranial doppler or MRA Hypercoagulable work-up if relevant
Thrombolysis (tPA) < 3 hrs (see contraindications); does no higher than 0.9mg/kg over 60 mins / RF for ICH older age, female, black, h/o CVA, HTN > 140/100 Consider anti-platelets if no hemorrhage ASA has been shown to have slight reduction in mortality and risk of recurrence (plavix may be more effective but slightly higher cost and GI bleed risk) Consider heparin if no hemorrhage no studies (as of 2001) show mortality increase with heparin for acute CVA (some neurologists use it in specific circumstances) maintain cerebral perfusion (so-called ischemia penumbra): do not overtreat HTN (SBP goal should be 160 to ?) watch for signs of progression/herniation Long-term Treat underlying cause (carotid stenosis, Afib, etc) Carotid Stenosis NASCET in patients with TIA/CVA and ipsilateral carotid artery stenosis > 70%, a carotid endarterectomy reduced stroke rate from 26% to 9% over 2 years ACAS 11% to 5% over 5 years if > 60% stenosis
4 to 20% will have stroke within next 90 days / 50% within 48 hrs / ABCD score used to help risk stratify / Age > 60 = 1, BP > 140/90 = 1, (unilateral weakness = 2; speech only = 1), (duration > 60 mins = 2; 10-59 mins = 1), diabetes = 1 Specific Stroke Syndromes Lateral medullary syndrome of Wallenberg - vertebral artery or PICA Clinical: loss of pain and temperature to ipsilateral face (descending spinal tract and nucleus of 5th CN) and contralateral body (spinothalamic tract), ipsilateral ataxia (cerebellar peduncle), ipsilateral Horner’s (descending sympathetic fibers), ipsilateral weakness of the palate and vocal cords (nuclei of 9th and 10th CN) / may present with nausea, vomiting, vertigo from involvement of vestibular system Mediobasal mesencephalic syndrome of Weber infarction of one cerebral peduncle / ipsilateral 3rd nerve palsy and contralateral hemiplegia [pic] Millard-Gubler syndrome – basilar artery damage to pons (left corticospinal tract proximal to decussation in medulla) 6th and 7th CN affected impaired lateral gaze, diplopia, facial weakness (all ipsilateral) [pic] contralateral hemiplegia mid basilar artery occlusion causes same thing only 5th CN ipsilateral and contralateral hemiplegia Hypertension Lenticulostriate arteries basal ganglia, pons, cerebellum, lacunes (small focal areas, lacunar infarcts) Clinical scenarios: motor hemiplegia, pure sensory stroke, ataxic-hemiparesis syndromes, “clumsy hand” dysarthria (base of pons or internal capsule) Charcot-Bouchard aneurysm aneurysms of lenticulostriate arteries Binswanger’s disease arteriolosclerotic encephalopathy Multi-infarct dementia second leading cause of dementia / step-wise progression (hemiparesis, extensor plantar response, pseudobulbar palsy) / hypoglycemia, vasculitis, infection, compression Venous and dural sinus thromboses infectious origin, hemorrhagic, often fatal Malformation berry aneurysms (80% single), AVMs (most common congenital, supratentorial) Perinatal cerebrovascular disease Germinal matrix hemorrhage post-hemorrhagic hydrocephalus, sub-ependymal cysts / small blue cell vessels, blood in ventricles Periventricular leukomalacia white matter infarct multicystic encephalomalacia ischemic lesions of grey matter pontosubicular karyorhexis (hyperoxemia)
Immunocompetent (from oral spread): peptostreptococcus > fusobacterium, bacteroides Immunocompetent: zygomyces, staphylococcus (possibly from bacteremia) glucose normal / increased risk with R-L shunt from congenital cardiac defect (blood skips alveolar macrophages in lungs) Evolution of brain abscess: early cerebritis (3 to 5 d), late cerebritis (5 to 14 d), early encapsulization (14 d, late encapsulization (weeks to months)
early normal or hypodense lesions on noncontrast CT / ill-defined enhancing lesions on contrast CT late ring-enhancing on contrast CT Drugs that penetrate CSF: Empyema may lead to superior saggital sinus thrombosis Congenital rubella, CMV Vasculitis mucor, aspergillus Amoebiasis N. fowleri, Acanthamoeba, Leptomyxid amoebae CNS malformations lissencephaly (agyria) agenesis of corpus callosum (batwing X-ray) Arnold-Chiari small posterior fossa / herniation of vermis into foramen magnum, hydrocephalus, lumbar myelomeningocoele syringomyelia soft cavitation of central canal, loss of pain/temperature bilaterally in upper extremities (light touch preserved) Dandy-Walker enlarged posterior fossa / absent cerebellar vermis, cyst protruding from 4th ventricle CNS trauma - accidents 4th most common COD in all ages fractures diastatic, comminuted, ring contusions plaque jaune CSF leak (from basilar skull fracture) CT air-fluid levels, opacification of paranasal sinuses, intracranial air Radioisotope cisternography or HRCT with water-soluble contrast (metrizamide cisternography) are the gold standards Epidural hematoma middle meningeal, skull fracture, lucid interval, progressive hemiparesis/obtundation and ‘blown pupil’ from herniation CT: lens-shaped convex hyperdensity Treatment: emergent neurosurgical evacuation Subdural hematoma Causes: bridging veins, head trauma, blood dyscrasias, elderly, alcoholics, child abuse (shaken baby) Presentation: headache, change in mental status, contralateral hemiparesis or other focal CT: crescent-shaped concave hyperdensity Treatment: neurosurgical evacuation if symptomatic / avoid anticoagulation Download 3.95 Mb. Share with your friends:
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