In the ED, Mr. Johnson’s chest pain was unrelieved after three sublingual nitroglycerin tablets

QUESTION

In the ED, Mr. Johnson’s chest pain was unrelieved after three sublingual nitroglycerin tablets. Morphine sulfate 5mg IVP was administered, resulting in a small decrease in pain. A chewable aspirin was also given. After evaluation of the initial laboratory results, presenting symptoms, and the EKG, the diagnosis was an extensive anterior MI.  Mr. Johnson was taken immediately to the cardiac catheterization laboratory for emergency angioplasty. The angiogram showed 90% blockage of the left anterior descending (LAD) artery. An emergency percutaneous transluminal coronary angioplasty (PTCA) was performed, but the artery continued to re-occlude, so a stent was placed. While the PTCA was being performed, Mr. Johnson became hypotensive, tachycardic, pale, cool, and diaphoretic. He complained of having shortness of breath, was restless, rales were auscultated throughout all lung fields, and he was found to have jugular vein distention (JVD). A CXR showed pulmonary edema. A dobutamine drip was started at 6 mcg/kg/min. Abciximab  (Reopro) bolus of 0.25mg/kg was given followed by an infusion at 0.125 mg/kg for 12 hours.. He was also given 40 mg furosemide IVP and a nitroglycerin drip was started. A pulmonary artery (Swan-Ganz) catheter was placed. An intra-aortic balloon pump (IABP) was inserted in the right groin.

13.) What are the rationales for the pharmacological agents (6) that Mr. Johnson received?

14.) Explain the rationales for both the Swan-Ganz catheter and IABP assist in Mr. Johnson’s plan of care.

ANSWER

13. Rationales for Pharmacological Agents Given to Mr. Johnson

a. Morphine Sulfate 5mg IVP: Morphine was administered to relieve Mr. Johnson’s chest pain, a typical symptom of myocardial infarction (MI). Morphine helps by reducing pain and anxiety, lowering myocardial oxygen demand, and dilating blood vessels. This can improve oxygen supply to the heart muscle by decreasing its workload.

b. Aspirin (Chewable):Aspirin was given to inhibit platelet aggregation. In an MI, platelet aggregation can worsen coronary artery blockage. Aspirin helps prevent further clot formation and reduces the risk of recurrent MI.

c. Dobutamine Drip (6 mcg/kg/min): Dobutamine is a sympathomimetic agent that was used to increase myocardial contractility and improve cardiac output. In the case of Mr. Johnson’s deteriorating condition, dobutamine helped support his failing heart and increase blood flow to vital organs.

d. Abciximab (Reopro) Bolus (0.25mg/kg) and Infusion (0.125 mg/kg for 12 hours): Abciximab is a glycoprotein IIb/IIIa receptor antagonist that prevents platelet aggregation and thrombus formation. It was administered to reduce the risk of re-occlusion of the stented artery and prevent further thrombotic events.

e. Furosemide (40 mg IVP): Furosemide, a loop diuretic, was given to manage pulmonary edema. It helps to reduce fluid overload and relieve the symptoms of congestion in the lungs, such as shortness of breath and rales.

f. Nitroglycerin Drip: Nitroglycerin is a vasodilator that was administered as a drip to reduce cardiac workload and improve coronary blood flow. It can relieve chest pain and reduce myocardial oxygen demand.

14. Rationales for Swan-Ganz Catheter and IABP in Mr. Johnson’s Plan of Care

a. Swan-Ganz Catheter: The Swan-Ganz catheter was inserted to monitor Mr. Johnson’s hemodynamic status closely. In his case, with signs of pulmonary edema, it was essential to assess parameters such as pulmonary artery pressure, central venous pressure (CVP), and pulmonary capillary wedge pressure (PCWP). This information helps in tailoring fluid management, vasopressor support, and diuretic therapy to optimize cardiac function and fluid balance.

b. Intra-Aortic Balloon Pump (IABP): The IABP was inserted to provide mechanical circulatory support. As Mr. Johnson developed hypotension, tachycardia, and signs of heart failure during the PTCA, it indicated that his heart was struggling to pump effectively. The IABP assists the heart by inflating and deflating in synchrony with the cardiac cycle. During inflation, it increases coronary perfusion by improving diastolic pressure in the aorta, while during deflation, it reduces afterload, making it easier for the heart to pump blood. This device helps maintain myocardial oxygen supply-demand balance and supports cardiac function in critically ill patients with MI.