醫學筆記匯整 ED Notes

- Most important shockable cardiac arrest rhythm
- Ventricles suddenly attempt to contract at rates of up to 500 bpm
   -> quivering mess 四處亂收縮

- Prolonged VF : Decreasing waveform amplitude,
  from initial coarse VF to fine VF and ultimately degenerating into asystole

-   Chaotic irregular deflections of varying amplitude 
-  No identifiable P waves, QRS complexes, or T waves
-  Rate 150 ~ 500 per minute
-  Amplitude decreases with duration (coarse VF -> fine VF)

-  VF should never be diagnosed from 12-lead ECG

 雙相去顫電擊 200 J or 單向 360 J  ( 死人直接開到最大 )

 

 Causes 

    Cardiac
        Myocardial ischemia / infarction
        Cardiomyopathy (dilated, hypertrophic, restrictive)
        Channelopathies e.g. Long QT (acquired / congenital) causing TdP –> VF and Brugada syndrome
        Aortic stenosis
        Aortic dissection
        Myocarditis
        Cardiac tamponade
        Blunt trauma (Commotio Cordis)
    Respiratory
        Tension pneumothorax
        Pulmonary embolism
        Primary pulmonary hypertension
        Sleep apnoea
        Bronchospasm
        Aspiration
    Toxic and metabolic causes
        Drugs (e.g. verapamil in patients with AF+WPW)
        Drug-induced QT prolongation with torsades de pointes
    Environmental
        Electrical shocks, drowning, hypothermia
        Sepsis
    Neurological
        Seizure
        CVA