Final answer:
In pulseless cardiac arrest, the nurse would anticipate administering epinephrine or vasopressin, with epinephrine being the primary medication used in such emergency situations. The correct answer is option a.
Step-by-step explanation:
A patient in pulseless cardiac arrest requires immediate treatment with medications that can stimulate the heart. The nurse would anticipate administering a medication that serves as a vasoconstrictor and can increase cardiac output and blood pressure. The medication most commonly used in such a scenario is epinephrine, which is an adrenergic agonist with potent vasoconstrictive and cardiac-stimulating effects.
Among the options provided, vasopressin is another medication that may be used as a secondary option to epinephrine in the advanced cardiac life support (ACLS) protocol for cardiac arrest. Vasopressin can increase vascular tone in cases of cardiac arrest by constricting blood vessels, which may help to maintain coronary and cerebral blood flow. However, epinephrine remains the primary medication administered during cardiac arrest situations.
Desmopressin, cosyntropin, and somatropin are not the primary medications used in treating a patient in pulseless cardiac arrest. Desmopressin is typically used to treat diabetes insipidus or to control bleeding in some types of hemophilia or Von Willebrand's disease. Cosyntropin is used as part of the ACTH stimulation test for diagnosing adrenal insufficiency, and somatropin is a form of human growth hormone used for growth hormone deficiency and other conditions.