Summary of study session IV 

In study session IV you have learnt 

• Cardinal features of sinus rhythm: The P wave is upright in leads I and II Each P wave is usually followed by a QRS complex, normal heart rate is 60-99 beats/min 
• Sinus bradycardia is common in normal individuals during sleep and in those with high vagal tone, such as athletes and young healthy adults. The electrocardiogram shows a P wave before every QRS complex 
• Pathological causes of sinus bradycardia: Acute myocardial infarction, Drugs—for example, beta blockers, digoxin, amiodarone, deep anesthesia, Obstructive jaundice, Raised intracranial pressure, Hypothermia, Hypothyroidism 
• Sinus tachycardia is usually a physiological response but may be precipitated by sympathomimetic drugs or endocrine disturbances. The rate 150- 200 beats/min in adults. Each P wave is followed by a QRS complex. 
• Ventricular tachyarrhythmia- Ventricular tachycardia and Polymorphic ventricular tachycardia (QRS complex wide). Rate is above 150/min, it could be pulseles or with pulse. Search for possible causes, ABC evaluation and care, if there is pulse administer Amiodarone 150mg over 10minute; or lidocaine 1mg/kg. If pulseles cardioversion. As a general rule the broader the QRS complex, the more likely the rhythm is to be ventricular in origin, 
• Ventricular fibrillation is the commonest unheralded fatal arrhythmia in the first 24 hours of acute myocardial infarction. 
• Asystole-a flat line with no clear electrical actiivty ,it is usually due to chronic illness 
• PEA- Pulseles Electrical Activity organized rhythm without a palpable pulse. 
• Goals of ACLS - Achieve adequate ventilation, Control cardiac arrhythmias, Stabilize BP and cardiac output and Restore organ perfusion 
• Strategy - continued CPR, Defibrillation/cardioversion or pacing, Intubation with endotrachial tube, or rescue device, IV line insertion and initiation of drug 
• Treatment of VF/pulseless VT: To attempt defibrillation, 1 shock is delivered using monophasic or biphasic waveforms followed immediately by CPR (beginning with chest compressions). 
• Rescuers should minimize interruptions in chest compressions and particularly minimize the time between compression and shock delivery, and shock delivery and resumption of compressions. 
• Insertion of an advanced airway may not be a high priority. If an advanced airway is inserted, rescuers should no longer deliver cycles of CPR. Chest compressions should be delivered continuously (100 per minute) and rescue breaths delivered at a rate of 8 to 10 breaths per minute (1 breath every 6 to 8 seconds). 
• Treatment of asystole/pulseless electrical activity: CPR +epinephrine administered every 3 to 5 minutes. One dose of vasopressin may replace either the first or the second dose of epinephrine. 
• Treatment of symptomatic bradycardia: the recommended atropine dose is now 0.5 mg IV, may repeat to a total of 3mg. Epinephrine or dopamine may be administered while awaiting a pacemaker. 
• Defibrillation is- passage of an electrical current of sufficient magnitude to depolarize a critical mass of myocardium and restoration of coordinated electrical activity (Phase I) used for Ventricular fibrilation and Pulseless ventricular tachycardia. 
• Biphasic defibrilator 200J, Monophasic 360J while in AED: Joules are device adjusted. 
• If a rhythm check shows persistent VF/VT, the appropriate vasopressor or antiarrhythmic should be administered as soon as possible after the rhythm check. It can be administered during the CPR that precedes (until the defibrillator is charged) or follows the shock delivery. 
• Identify contributing factors and address accordingly. See for the 5H and 5T. 5H (hypoxia, hypovolemia, hypokalemia/hyperkalemia, hydorgen/acidosis ,hypothermia), and 5T(Toxins ,tamponade, thromboembolism, Tension PT, trauma)