Tick the drug, blocking acetylcholine transmission at the myoneural junction of helminthes:

Correct Answer: A

Rationale: The correct answer is A: Levamisole. Levamisole blocks acetylcholine transmission at the myoneural junction of helminthes by inhibiting cholinesterase enzyme. This leads to paralysis and expulsion of the parasites from the host. Mebendazole (B) works by inhibiting microtubule synthesis in helminthes. Piperazine (C) causes paralysis by hyperpolarizing the helminth's muscle cells. Niclosamide (D) disrupts the helminth's energy metabolism. Therefore, Levamisole is the correct choice for blocking acetylcholine transmission specifically.

Correct Answer: B

Rationale: The correct answer is B: Adenosine. Adenosine is commonly used for treating supraventricular tachycardias, which can cause palpitations. It works by slowing electrical conduction in the heart, helping to restore normal heart rhythm. Mexiletine (A) is a sodium channel blocker used for ventricular arrhythmias. Sotalol (C) is a beta-blocker used for atrial and ventricular arrhythmias. Verapamil (D) is a calcium channel blocker used for atrial arrhythmias but not typically for palpitations due to supraventricular tachycardias.

Correct Answer: F

Rationale: The correct answer is B: Mexiletine. After administering amiodarone for atrial fibrillation and wide QRS, the next drug should target the wide QRS complex, indicating possible ventricular involvement. Mexiletine, a Class IB antiarrhythmic, is commonly used to treat ventricular arrhythmias. Lidocaine (A) is also a Class IB antiarrhythmic, but Mexiletine is preferred in this scenario due to its longer half-life. Phenytoin (C) is not indicated for atrial fibrillation or wide QRS. Nifedipine (D) is a calcium channel blocker and is not appropriate for treating ventricular arrhythmias.

Correct Answer: B

Rationale: In this scenario, the correct answer is B) Ibutilide. Ibutilide is a class III antiarrhythmic agent that is effective in the acute management of atrial fibrillation or atrial flutter of recent onset. Ibutilide exerts its antiarrhythmic effects by prolonging the cardiac action potential and refractory period, thereby helping to restore normal sinus rhythm in patients with atrial fibrillation or flutter. Its mechanism of action involves blocking the rapid component of the delayed rectifier potassium current (IKr), leading to prolongation of the repolarization phase of the cardiac action potential. Now, let's analyze why the other options are incorrect: A) Bretylium: Bretylium is a class II antiarrhythmic agent that is primarily used for the management of ventricular arrhythmias. It is not typically used for the acute management of atrial fibrillation or flutter. C) Metoprolol: Metoprolol is a beta-blocker, which is classified as a class II antiarrhythmic agent. While beta-blockers are commonly used for rate control in atrial fibrillation, they are not typically used for the acute conversion of atrial fibrillation or flutter. D) Disopyramide: Disopyramide is a class I antiarrhythmic agent, specifically a class IA antiarrhythmic. It is more commonly used for the management of ventricular arrhythmias and is not typically used for acute management of atrial fibrillation or flutter. In an educational context, understanding the classification of antiarrhythmic drugs is crucial for healthcare professionals, especially nurses, who may encounter patients with various cardiac arrhythmias. It is essential to know the mechanism of action and appropriate use of each class of antiarrhythmic drugs to provide safe and effective care to patients with cardiac rhythm disturbances.

Correct Answer: A

Rationale: In the acute management of angina pectoris, the agent given sublingually is Glyceryl trinitrate (Option A). Rationale: 1. **Correct Answer**: Glyceryl trinitrate is a fast-acting vasodilator that helps to dilate coronary arteries, increasing blood flow to the heart. Administered sublingually, it quickly enters the bloodstream, providing rapid relief from angina symptoms. 2. **Incorrect Options**: - B) Amyl nitrite: While also a vasodilator, it is typically used in the past for angina attacks but is not commonly used today. - C) Erythrital tetranitrate: This drug is not a commonly used medication for acute angina attacks. - D) Pentoerythritol tetranitrate: This medication is not typically administered sublingually for acute angina treatment. 3. **Educational Context**: Understanding the appropriate medications for the management of acute conditions like angina pectoris is crucial for healthcare providers, especially nurses. By knowing the correct medication and route of administration, nurses can promptly and effectively manage patients experiencing angina attacks, potentially preventing serious complications like myocardial infarction. In conclusion, Glyceryl trinitrate is the preferred choice for sublingual administration in acute angina attacks due to its rapid onset of action and effectiveness in relieving symptoms. Nurses must be well-versed in the appropriate use of cardiovascular drugs to provide optimal care to patients in various clinical settings.