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Syncope and Seizures

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					Medical Emergencies – Syncope & Seizures – 10th CME




Presented by: Dr Gaurav,
GGN Medical Team

Date: 7th Sept 07
                                 SYNCOPE



•   Syncope is defined as a sudden ,transient loss of consciousness
characterized by unresponsiveness and loss of postural tone.


•   Occurs in up to 50% of adults, and 75% over age 75
•   Accounts for up to 3% of ER visits, 6% of admissions


•   Up to one third of syncope cases are idiopathic
•   The prognosis for most persons with syncopal episodes is good; however,
    persons with syncope caused by a cardiac disorder have a one-year mortality
    rate of 20-30% and a 33% incidence of sudden death over 5 years.
                                  Etiology of Syncope
          The cause of syncope can not be determined in 38-47% of cases


Non-Cardiac Causes (57%)                  Cardiovascular (10-30% of causes)


Metabolic                                 Reflex syncope (heart structurally normal)
Hyperventilation                          Vasovagal,
Hypoglycemia                              Situational
Hypoxia                                   Cough, Defecation ,Micturition ,Postprandial,Sneeze,
                                          Swallow
                                          Carotid sinus syncope
Neurologic (9% of causes)                 Orthostatic hypotension (2-24%)
                                          Drugs
Cerebrovascular insufficiency , Seizure
Subclavian steal syndrome
Increased intracranial pressure ,



Psychiatric                               Cardiac
Hysteria , Major depression
    Cardiovascular (10-30% of causes)
•   Arrhythmia
          Ventricular Tachycardia
          Sick Sinus Syndrome
          Supraventricular Tachycardia
          Atrioventricular Block (second or third degree)
          Pacemaker malfunction
•   Aortic Stenosis
•   Mitral Stenosis
•   Myocardial Infarction
•   Aortic Dissection
•   Pulmonary Embolism
•   Pulmonary Hypertension
•   Subclavian Steal Syndrome
•   Hypertrophic Cardiomyopathy
•   Atrial myxoma

     Orthostatic Syncope (2-24%)
Reflex Mediated Syncope (no cardiovascular risk)

•   Vasovagal Syncope (Vasodepressor Syncope)
     Situational syncope
          Micturition syncope or with Defecation
          Cough syncope (or sneezing)
          Valsalva (brass instrument playing, weight lifting)
          Hyperventilation

•   Carotid Sinus Syncope

•   Glossopharyngeal neuralgia (uncommon)
         Syncope occurs with swallowing, talking, sneezing
•   Orthostatic Syncope (2-24%)

Neurologic Causes (9% of causes)
                     Transient Ischemic Attacks: 1-7%
                     Seizure disorder: 2%
                           Orthostatic Hypotension

Definition
Blood Pressure drop on standing of >20/10
Occurs within 3 minutes of standing
Physiology
Rising from lying to standing position
     300 to 800 ml of blood pools in legs

Physiologic response
    Lower extremity Muscle contraction compresses veins
    Autonomic response
          Baroreceptors in aorta and carotids sense BP change
          Sympathetic nervous system responds by
               Increasing vascular tone
               Increasing Heart Rate and cardiac contractility
  Blood Pressure and Pulse examination in orthostatic
                      hypotension

    Supine Blood Pressure, pulse after 3-5 minutes
    Standing Blood Pressure, pulse after 3-5 minutes
    Abnormal if Blood Pressure drops >20/10

Response to 15 second Valsalva maneuver
   Normally pressure falls, then rises over baseline
   Abnormal if pressure does not overshoot baseline

Pulse variation on deep breathing (sinus arrhythmia)
    Normal response
         Tachycardia on inspiration
         Bradycardia on expiration
    Abnormal if <9 beat/min difference during cycle
Management :Orthostatic hypotension

•Avoid medications related to orthostasis
•Modify diet
                        Increase salt and water intake
                        Avoid alcohol
                        Eat smaller, more frequent meals
•Modify activity
     • Avoid heat exposure or strenuous Exercise
     • Sleep with head of bed slightly elevated
     • Rise from bed slowly allowing for equilibration
     • Avoid standing for long periods of time
     • While standing, move frequently
     • Avoid work with arms above shoulder height
     • Dorsiflex feet several times before standing

    • Consider Compression stockings

• Consider medication therapy
          Review precautions before using
              Fludrocortisone (Florinef)
              Erythropoietin has been used if comorbid Anemia
                  CAROTID SINUS SYNCOPE

Category : Carotid sinus hypersensitivity
Epidemiology: Most often occurs in patients over age 60 years

Symptoms: Provocative maneuvers
    Head turning
    Tight shirt collar
    Valsalva maneuver
    Shaving
Signs
    Electrophysiologic evaluation normal
    Carotid Sinus Massage results in one of three findings
         Three second sinus pause
         Sinus Bradycardia
         Atrioventricular Block
              Medication-related syncope

•   Antihypertensive Medications (e.g. Beta Blocker)
          Ophthalmic Beta Blockers

•   Antianginal medications (e.g. Nitroglycerin)

•   Digitalis
     Atrioventricular Block
     Ventricular Tachycardia
•   Antiarrhythmic medications (esp. Type Ia)

•   Diuretics
     Hypokalemia
     Hypomagnesemia
     Hypovolemia

•   Phenothiazines
•   Tricyclic Antidepressants
•   Recreational drug use {Alcohol Ecstasy(DMA)
    Methamphetamine}
                           History & Examination

  The history and physical examination can identify potential causes of
    syncope in 50-85% of cases in which a successful diagnosis is made

Predisposing Conditions
    •   Family History of Sudden Cardiac Death (e.g. SADS)
    •   Diabetes Mellitus (Hypoglycemia)
    •   Parkinson's Disease (Orthostatic Hypotension)
    •   Seizure Disorder
Preceding or provocative event
    •   Prolonged standing (e.g. Vasovagal Syncope)
    •   Immediately on standing (Orthostatic Hypotension)
    •   With exertion (Cardiomyopathy, CAD, Valve stenosis)
    •   After exertion in an athlete (Vasovagal Syncope)
    •   Valsalva (cough, swallowing, urinating or stooling)
    •   Neck rotation or pressure (e.g. tight collar) Carotid Sinus Hypersensitivity
    •   Use of arms (Subclavian Steal Syndrome)
    •   Stressful event (Vasovagal Syncope)
Associated symptoms during event

    Nausea, chills and sweats      : Vasovagal Syncope
    Aura                           : Migraine Headache, Seizure Disorder
    Chest pain, palpitation        : Coronary Artery Disease,arrhythmia
    Movements occur before fall : Seizure disorder
    Movements occur after fall : Vasovagal Syncope
    Incontinence of urine or stool : Seizure



Duration

    Brief loss of consciousness (arrhythmia)
    Loss of consciousness >5 minutes
          Neurologic, metabolic, or infectious cause
    Tonic-clonic movements
                              Signs

General
    Pallor (Orthostatic Hypotension due to Anemia)
    Tongue bitten (Seizure)
Cardiovascular examination
    Carotid Bruits
    Heart Murmur
    Asymmetric pulses
    Carotid massage
    (Avoid in Cerebrovascular Disease or Carotid Bruit)
Neurologic Exam
    Post-event Confusion (Seizure Disorder)
    Focal neurologic deficit
Labs and diagnostic testing: Initial evaluation

    •    Serum electrolytes including glucose
    •    Hemoglobin or Hematocrit
    •    Electrocardiogram
    •    Chest XRay
    •    Brain Natriuretic Peptide (BNP)
         BNP > 40 pg/ml strongly suggests cardiac cause
         Test Sensitivity: 82%
         Test Specificity: 92%
    •    Additional tests to strongly consider
              Serial Troponin I and inpatient telemetry monitoring
              Cardiac stress testing
              Event Monitor or Holter Monitor
              Echocardiogram
     Hospitalization Indications

•   Syncopal episode occurring during Exercise
•   Family History of sudden death
•   Severe Orthostatic Hypotension
•   Suspected underlying serious cause
        Coronary Artery Disease
        Cardiac arrhythmia
        Cerbebrovascular accident
    Reassuring findings suggestive of neurally-mediated causes


•   No cardiac history
•   Chronic history of syncope
•   Triggered by specific stimulus
         Noxious smell, sound, sight or pain
         Prolonged standing, crowded place, heat
         Nausea or Vomiting
         Post-meal
         Rotation of head or tight collar, shaving
         Post-exertion
                   San Francisco Syncope Rule

•   Predicts short-term risk of serious outcome
•   Evaluate short-term risk of serious outcome
•   May reduce Syncope hospitalization rate

Criteria (Mnemonic: CHESS)
     Congestive Heart Failure history
     Hematocrit <30%
     Electrocardiogram abnormal
     Shortness of Breath
     Systolic Blood Pressure <90 mmHg at triage
Interpretation
     Positive: One of criteria above
     Mortality 10% within 6 months of cardiovascular syncope
     Test Sensitivity: 96% (misses 4% of cases)
     Test Specificity: 62%
                           Seizure

A seizure is an abnormal, unregulated electrical discharge that
occurs within the brain's cortical gray matter and transiently
interrupts normal brain function.

A seizure disorder (epilepsy) is diagnosed when a patient has
≥ 2 seizures not related to reversible cause
                                              Etiology
Autoimmune disorders
Cerebral vasculitis, multiple sclerosis (rarely)
Cerebral edema
Eclampsia, hypertensive encephalopathy, ventricular obstructionCerebral
Ischemia
Adams-Stokes syndrome, cerebral venous thrombosis, embolic cerebral infarcts, vasculitisCerebral
trauma Birth injury, skull fracture, penetrating injuries
CNS infections
AIDS, brain abscess, falciparum malaria, meningitis, neurocysticercosis, neurosyphilis, rabies,
toxoplasmosis, viral encephalitis
Congenital or developmental abnormalities
Drugs
Cocaine, other CNS stimulants,
                                    Management
•Most seizures remit spontaneously in several minutes and do not require emergency
drug treatment , but maintanance of airway is required
•Status epilepticus and most seizures lasting > 5 min require drugs to terminate the
seizures, with monitoring of respiratory status.
•.IV access should be quickly obtained, and lorazepam 0.05 to 0.1 mg/kg IV is given at
a rate of 2 mg/min. Large doses are sometimes required.
•If seizures continue after about 8 mg is given,
•Fosphenytoin 10 to 20 PE /kg IV is given at a rate of 100 to 150 PE/min
•Phenytoin 5 to 20 mg/kg IV at a rate of 50 mg/min is a 2nd choice.
•Additional seizures require an additional 5 to 10 PE/kg of fosphenytoin or 5 to 10
mg/kg of phenytoin
•Persistent seizures after lorazepam defines refractory status epilepticus
• Recommendations for a 3rd anticonvulsant vary and include

     phenobarbital propofol, midazolam, and valproate
Contd…….
•Phenobarbital 15 to 20 mg/kg IV at 100 mg/min (3 mg/kg/min in children) is given;
continued seizures require another 5 to 10 mg/kg.
•A loading dose of valproate 10 to 15 mg/kg IV is an alternative. At this point, if status
epilepticus has not abated, intubation and general anesthesia are necessary.
•The optimal anesthetic to use is controversial, but many physicians use
     Propofol 15 to 20 mg/kg at 100 mg/min
                    or
      Pentobarbital 5 to 8 mg/kg (loading dose) followed by infusion of 2 to 4 mg/kg/h
until EEG manifestations of seizure activity have been suppressed.
• Inhalational anesthetics are rarely used. After initial treatment, the cause for status
epilepticus must be identified and treated.
Thank You

				
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posted:9/5/2012
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