Med-Surg - Cardiovascular System, part 18: Myocardial Infarction, PCI, CABG

Hi, I'm Cathy with LevelUp RN. In this video, we are going to talk about a myocardial infarction as well as a PCI, which is a percutaneous coronary intervention, and then we'll also talk about CABG surgery. So this is a coronary artery bypass graft. At the end of the video, I'm going to provide you guys a little quiz, a little knowledge check, to test your understanding of some of the key facts I'll be covering in this video. So definitely stay tuned for that. And if you have our LevelUp RN medical surgical nursing flashcards, definitely pull those out so you can follow along with me.

A myocardial infarction is where we have a sudden blockage of blood flow into the heart, and the pathophysiology behind an MI is that when a patient has atherosclerosis, so the plaque on the coronary artery wall, this plaque can rupture, causing a thrombus, and that in turn occludes blood flow into the heart.

Signs and symptoms include chest pain and discomfort, shortness of breath, diaphoresis, as well as dizziness. Women sometimes have different symptoms, which may include nausea and vomiting, as well as fatigue, pain in their back, shoulders or jaw.

In terms of diagnostics, if we run labs, the patient will have elevated cardiac enzymes, and then their EKG may show abnormal ST elevation or depression. It may show T wave inversion or an abnormal Q wave as well. We can also do what's called a thallium scan, which is a nuclear imaging test to see how well blood flows into the heart. And then a cardiac catheterization can also be used as a diagnostic test.

Medications used in the treatment of an MI can include aspirin, clopidogrel, as well as thrombolytic anticoagulants, antihypertensive agents such as beta blockers and ace inhibitors, and statins. And I go through all of these medications in depth in my pharmacology playlist, so definitely check that out if you need to.

In terms of surgical interventions, we have a PCI, which is a percutaneous coronary intervention, which we're going to talk more about here in a minute. We also have a CABG surgery, which is a coronary artery bypass graft surgery. And then an atherectomy can also be done which is a surgery to remove the plaque from the artery.

In terms of nursing care, we're going to administer oxygen for an SpO2 that is below 90% per orders, and then we're going to want to monitor the patient for complications such as cardiogenic shock and heart failure. And just as a reminder about the signs and symptoms of cardiogenic shock, those include hypotension, tachycardia, tachypnea, as well as weak pulses.

And then we're going to initiate cardiac rehabilitation for the patient. This is an outpatient program that focuses on exercise and education for the patient. A PCI, or percutaneous coronary intervention, is a procedure used to open up the coronary arteries, and it must be performed within two hours of the onset of symptoms of an MI. That's why if you or someone you love has any symptoms of an MI, you should get immediate attention.

So during this procedure, a catheter with a balloon is threaded through a blood vessel, usually at the femoral artery, up to the blocked coronary artery. And there the balloon is inflated and a stent is placed to restore blood flow to the heart.

After the procedure, you should monitor the insertion site for bleeding, and you definitely need to check perfusion to the extremity that is distal from that insertion site. So check that extremity for pulses, color and temperature. You also want to monitor the patient for complications, which can include an artery dissection, as well as re-occlusion of the coronary artery. So definitely be on the lookout for symptoms such as shortness of breath, chest pain, tachypnea, as well as tachycardia.

The coronary artery bypass graft procedure bypasses one or more of the patient's coronary arteries due to blockage or persistent ischemia, and it typically uses the saphenous vein from the patient's leg. However, synthetic grafts can be used as well.

In terms of nursing care after the procedure, we're going to want to closely monitor the patient's blood pressure because if the patient has hypertension that can cause bleeding from the graft sites. And if the patient has hypotension, that can cause collapse of the graft. So we're going to really monitor the blood pressure and keep it in that narrow therapeutic window. We're also going to monitor the patient's temperature because post-op hypothermia is a potential complication. If needed, we should use rewarming procedures to help bring the patient's temperature back up. We're also going to monitor the patient for bleeding so they will have a chest tube when they come back from surgery, and you're going to want to closely monitor the drainage in that chest tube. If it exceeds over 150 milliliters per hour, you need to notify the provider. You're also going to assess the patient's level of consciousness, their fluid and electrolyte balance, as well as their cardiac rhythm, their pain level and the neurovascular status of the donor site. So we definitely don't want to neglect the leg where we got that saphenous vein. And then we're going to monitor the patient for complications, which can include a cardiac tamponade. And if you need a reminder about the signs and symptoms of that condition, definitely watch my video on that topic.

All right, time for a quiz. I have three questions for you. First question. Symptoms of a myocardial infarction will be the same for men and women. True or false? The answer is false. So women will often have symptoms such as nausea and vomiting, fatigue and pain in their back, shoulders, or jaw.
Question number two. A percutaneous coronary intervention must be performed within blank hours of the onset of MI symptoms. The answer is two.
Question number three. What vein is often used to bypass the blocked coronary artery during a CABG procedure? The answer is the saphenous vein.
Okay, I hope you enjoyed that quiz, and I hope this video was helpful. Take care and good luck studying.