chapter Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ 7 Acute Myocardial Infarction Pathophysiology

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Chapter 7 Objectives Describe the myocardial coronary blood supply Name the major coronary arteries and locations they serve Describe how clot and plaque formation relate to the development of an acute myocardial infarction Describe an intervention plan for managing myocardial infarction Explain why getting a good medical history is so important in the AMI patient List the most common presentations of AMI for women and the elderly 74

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Coronary Arteries Branch off of the aorta, just above the leaflets of the aortic valve Three major arteries Each supplies a specific area 75

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Right Coronary Artery Inferior wall of LV Right ventricle Posterior LV Posterior fascicle of LBB SA and AV node 76

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Left Anterior Descending Anterior wall of LV Septum Bundle Branches Hemifascicles Major pumping mass of LV 77

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Left Circumflex Artery Upper lateral wall of LV (Leads I and aVL) SA node in 45% AV node in 10% Posterior wall of LBB Posterior hemifascicle 78

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Occlusion Data In general, patients with chest pain on exertion have 70-85% narrowing Those with CP at rest have 90% occlusion Those with chest pain not relieved by nitroglycerin have 100% occlusion with a clot!! 79

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Getting a Good History It is HOW we ask the questions Mnemonics (OPQRST) are memory aids Should not be asked literally to a patient 80

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Investigating the C/C O– Onset P– Provoke Q– Quality R– Radiation S– Severity T– Time 80

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ What to Ask O – Onset P – Provoke Q – Quality R – Radiation S – Severity T – Time Actual time this episode started Open-ended questions Try to get an actual time, i.e., 10:30 a.m. Very important for cardiac patients

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Onset “When did this episode of chest pressure start?” “When did this asthma attack start?” “When did the accident occur?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Onset Avoid using closed or leading questions... “Did the pain start last night or this morning?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ O – Onset P – Provoke Q – Quality R – Radiation S – Severity T – Time What makes it better or worse Note the position of the patient What they were doing when it happened What to Ask

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Rule # 1 of Questioning While investigating a chief complaint, the only words you may use are the words the patient told you

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Rule # 1 If the patient tells you : “I’m having a tightness in my chest.” You would reply : “When did this tightness start, Jim?” Rather than: “When did the pain start, Jim?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Provoke “Jim, does anything you do make the tightness worse?” “Does anything you do make the tightness less?” “Jim, what were you doing when this tightness first started?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ What to Ask O – Onset P – Provoke Q – Quality R – Radiation S – Severity T – Time What it feels like Avoid closed and leading questions Let the patient have as many choices as they like to describe their “pain”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Quality “Jim, what does this “pain” feel like?” “What would I have to do to you to make that kind of “pain?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Closed or Leading Questions “Is the pain sharp or dull?” “Does the pain kinda feel like a belt around your chest?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ What to Ask O – Onset P – Provoke Q – Quality R – Radiation S – Severity T – Time Do they have any problems or pain anywhere else Watch for nonverbal clues Where the pain is Pain may not “go” anywhere

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Radiation Instead of “Does the pain go anywhere?” Try “Are you having any other discomfort?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Radiation Instead of “Does it hurt in the center or side of your chest?” Try “Where does it hurt?” or “Can you draw a circle around it?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ What to Ask O – Onset P – Provoke Q – Quality R – Radiation S – Severity T – Time Scale of 1–10 Make sure you find out what the worst pain was Answers of >10 mean it hurts really BAD!

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Severity “On a scale of 1–10 with 10 being the worst pain you’ve ever had, how would you rate your pain right now?” “What was the worst pain you have ever felt?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ What to Ask O – Onset P – Provoke Q – Quality R – Radiation S – Severity T – Time The duration of the problem How long the current episode has been going on

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Time “How long has this recent episode of chest pressure lasted, Jim?” “How long did Jim’s seizure last?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Tag-ons Tag-ons are extra questions tacked on to the end of an ordinarily good question

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Tag-ons “ Do you have diabetes, hypertension, or cardiac disease?” “Are you nauseated?” “Are you short of breath?” “Are you having chest pain?” “Is it sharp or dull?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Tag-ons The best way to avoid a tag-on is to ask one question at a time and wait for the answer

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ SAMPLE History S – Signs/symptoms A– Allergies M– Medications P– Past History L– Last meal E– Events 81

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Allergies “Jim, are you allergic to any medications?” “Sue, are you allergic to anything?” “Do you have any allergies, Jane?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Medications “Do you take any doctor-prescribed medicines every day?”

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Medications Explore the details BCPs? OTC Drugs? How many?

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Past Medical History Ask one question at a time Allow the patient time to answer Explore what is pertinent

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Last Oral Intake Very important in diabetic emergencies Important information for patient who may have to have surgery Need to know when they ate last (time) and approximate amount

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Events Leading up to C/C What were they doing when the episode started? Mechanism of injury? Useful for neuro exam in head injuries Pain at rest or on exertion?

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Physical Exam Head to toe Look for JVD Assess lung and heart sounds Palpate the chest wall Palpate the abdomen Palpate radial pulses at the same time 81

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Physical Exam (cont.) Blood pressure in each arm Positional changes for the patient Apical versus radial pulses Full auscultated blood pressure Look for peripheral edema

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ The 12-Lead ECG Best “early” confirming diagnostic test Should be performed on any patient with a “pulse and problem” between nose and naval that is suspicious for cardiac Should be acquired and triaged in less than 10 minutes arrival on scene 82

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Acute Coronary Syndrome Systems should address the following treatment guidelines: Oxygen and aspirin as soon as possible Establish an IV, run a 15-lead ECG Nitroglycerin Morphine Thrombolytic prescreen

Page, 12-Lead ECG for Acute and Critical Care Providers © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Sample Thrombolytic Checklist 83