This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S., Subject name: Medicine
In ACLS which drug can be given following ventricular fibrillation after cardiac arrest in place of Epinephrine? 
Select and explain. 
A. Amiodarone infusion, B. Atropine, C. High dose vasopressin, D. Adenosine
C: High dose vasopressin
Answer: C: High dose vasopressin 
Explanation: (C) High dose vasopressinCPR Quality:-Push hard (>2:2") & fast (>=2:100/min) & allow complete chest recoil.-Minimize interruptions in compressions-Avoid excessive ventilation-Rotate compressor every 2 minutes-If no advanced airway, 30:2 compression-ventilation ratio-Quantitative waveform capnography-If PETCO2<10mmHg, attempt to improve CPR quality-Intra-arterial pressure: If relaxation phase (diastolic) pressure <20mmHg, attempt to improve CPR quality.Return of Spontaneous Circulation (ROSC):-Pulse and blood pressure-Abrupt sustained increase in PETCO2 (typically >40mmHg)-Spontaneous arterial pressure waves with intra-arterial monitoringShock Energy:-Biphasic: Manufacturer recommendation (120-200J); if unknown, use r maximum available. 2nd & subsequent doses should be equivalent, and higher doses may be considered.-Monophasic: 360 JDrug Therapy:-Epinephrine IV/10 Dose: 1 mg every 3-5 minutes-Vasopressin IV/10 Dose: 40 units can replace 1s' or 2nd dose of epinephrine-Amiodarone IV/10 Dose: First dose: 300 mg bolus. Second dose: 150 mg.Advanced Airway:-Supraglottic advanced airway or endotracheal intubation-Waveform capnography to confirm and monitor ET tube placement-8-10 breaths per minute with continuous chest compressionsReversible Causes:- Hypovolemia - Tension pneumothorax- Hypoxia - Tamponade, cardiac- Hydrogen ion (acidosis) - Toxins- Hypo-/hyperkalemia - Thrombosis, pulmonary- Hypothermia - Thrombosis, coronary[?]VASOPRESSIN:oVasopressin is an alternative vasopressor at high doses, causes vasoconstriction by directly stimulating smooth muscle V1 receptors.oAmerican Heart Association (AHA) guidelines states "Vasopressin is a reasonable first-line vasopressor in patients with ventricular fibrillation or pulse-less ventricular tachycardia.oAdditionally, the guidelines comment that one dose of vasopressin 40 U may replace the first or second dose of epinephrine in all pulse-less sudden cardiac arrest scenarios, including asystole and pulse-less electrical activity, Cardiac arrest scenarios, including asystole and pulse-less electrical activity.oContraindications/Precautions:-Potent peripheral vasoconstrictor (increased demand upon resuscitation)oDosing:-Single dose of 40 u that replaces either the 1st or 2nd dose of epinephrine. Epinephrine can be resumed 3-5 minutes after.-Can be used endotracheally; no suggested dose.-V-Fib or VF is the most common rhythm that occurs immediately after cardiac arrest. In this rhythm, the heart beats with rapid, erratic electrical impulses.oTreatment:-Shock/De-fibrillation: every 2 minutes in a single one shock, successive, shock-able increments-200 joules - Followed by immediate CPR for 2 minutes/give and circulate a drug(s)-300 joules - Followed by immediate CPR for 2 minutes/give and circulate a drug(s)-360 joules - Followed by immediate CPR for 2 minutes/give and circulate a drug(s)oDrugs:-Give Epinephrine 1mg of a 1:10,000 solution every 3 to 5 minutes -Give either:-Amiodarone : 300mg first dose/150mg second dose at 3 to 5 minutes increments.oLidocaine: First dose: 1mg/kg or 1.5mg/kg. Can repeat it at half the original dose up to a total of 3mg/kg .