Final answer:
Vasopressin was previously used in a dose of 40 units for VF/PVT cardiac arrest, but it has been removed from the latest cardiac arrest treatment guidelines due to insufficient evidence of superiority over adrenaline. Its use is now more specialized and not routine for VF/PVT.
Step-by-step explanation:
The question you've asked pertains to the use of Vasopressin in the context of cardiac arrest, specifically when a patient is experiencing ventricular fibrillation (VF) or pulseless ventricular tachycardia (PVT). Vasopressin is a potent endogenous hormone known for its vasoconstrictive properties. In the setting of cardiac arrest, it has been considered as an alternative to adrenaline (epinephrine) to increase coronary and cerebral perfusion pressure during CPR.
The standard vasopressin dosing for adult cardiac arrest caused by VF/PVT, according to previous ACLS (Advanced Cardiac Life Support) guidelines, was 40 units administered intravenously or intraosseously as a one-time dose. However, it's important to note that in the most recent guidelines, vasopressin has been removed from the recommended treatment algorithm for cardiac arrest due to a lack of evidence suggesting a significant advantage over the use of adrenaline alone.
While vasopressin can still be used in the hospital setting, its role has become more specialized and it is not commonly used for the initial treatment of VF/PVT cardiac arrest in the prehospital or most emergency department settings.