In: Nursing
a. Jasper has been admitted to the emergency room after experiencing a myocardial infarction. His electrocardiogram displayed significant elevation of the ST-segment, and his biochemical work identified the release of cardiac enzymes and normoxia. He required pharmacological and percutaneous intervention. Discuss the appropriateness of administration of the following treatments to him: isosorbide dinitrate, oxygen, and anistreplase.
b. While in the hospital, Jasper develops arrythmias. His doctor prescribes lidocaine for the treatment thereof. Explain i) how lidocaine decreases arrythmias, and ii) which route of administration would be used and why.
Ans) Isosorbide dinitrate is in a group of drugs called nitrates. Isosorbide dinitrate dilates (widens) blood vessels, making it easier for blood to flow through them and easier for the heart to pump. Isosorbide dinitrate is used to treat or prevent attacks of chest pain (angina).
- Oxygen therapy may decrease cardiac blood flow and perfusion, reduce cardiac output, and increase coronary vascular resistance. If myocardial reperfusion is achieved, oxygen may have a paradoxical effect by inducing reperfusion injury through production of oxygen free radicals.
- Anistreplase cleaves the Arg/Val bond in plasminogen to form plasmin. Plasmin in turn degrades the fibrin matrix of the thrombus, thereby exerting its thrombolytic action. This helps eliminate blood clots or arterial blockages that cause myocardial infarction.
- Lidocaine is a class IB antiarrhythmic drug. Lidocaine blocks cardiac sodium channels shortening the action potential, thus decreasing the rate of contraction of heart and is used intravenously only for arrhythmia.
- Lidocaine may also be administered by subcutaneous, intramuscular or intravenous injection. Not intended for use in the eye. The usual adult IV bolus dose is 50-100 mg administered at a rate of approximately 25-50 mg per minute.