Transcript Document
N402 1 Angina is caused by insufficient O2 to part of the myocardium Therefore, angina is relieved by decreasing O2 to the myocardium! Accomplished by: Decrease the heart rate… Dilate the veins (decrease preload)… Decrease contractility… or, Decrease BP (decrease afterload) 2 βBlockers Ca Channel Blockers Organic Nitrates 4 Requires drugs from 2 classes because each class relieves angina from a different approach… β-Blockers slow heart rate and decrease contractility… Ca Channel Blockers decrease afterload…, and Organic Nitrates decrease preload 5 Slow the heart rate and decrease contractility Therefore, afterload is decreased Used to treat both hypertension and angina Not effective on Prinzmetal’s angina 6 Relax arteriolar smooth muscle to decrease BP Therefore, decrease afterload Also dilate coronary smooth muscle Useful in treating Prinzmetal’s angina 7 Dilation of veins decreases amount of blood returning to heart Therefore decreases preload Also dilates coronary arteries Useful in treating Prinzmetal’s angina May be short acting (NTG) or long acting (isosorbide) 8 Sudden blockage of coronary artery by dislodged plaque Causes coagulation cascade Results in: UNSTABLE ANGINA Incomplete occlusion by thrombus Causes chest pain INFARCTION Complete occlusion by thrombus Causes ischemia and necrosis 9 Goals of treatment: Unstable angina Relief of pain Prevent clot enlargement Myocardial infarction Restore blood supply Prevent thrombus enlargement Decrease O2 demand Prevent dysrhythmias Manage pain 10 Should be given within first 20 minutes to 12 hours Risk is excessive bleeding Not everyone is a candidate Use with caution in the elderly 11 Anticoag. ASA/clopidogrel ↓ O2 demand Antianginal Β-Blockers Nitrates Pain Mgt MS ACEI 12 Occurs when there is insufficient blood supply to vital organs by cardiovascular system Major types of shock: Hypovolemic Excessive blood loss Cardiogenic Pump failure Septic Toxins in blood Neurogenic Sudden loss of sympathetic activity 13 Used when fluids alone are ineffective Rapid onset, short duration Given by continuous IV until patient is stabilized Dopamine (Dopastat, Intropin 2-5 mcg/kg/min; up to 20-50 mcg/kg/min Norepinepherine (Levophed) 0.5 mcg/min up to 8-30 mcg/min Phenyephrine (Neo-Synepherine) Epinephrine Watch closely for adverse effects: BP changes, dysrhythmias, necrosis at infusion/injection site (Regitine) 14 Commonly associated drugs: Antibiotics—especially PCNs, cephalosporins, sulfonamides NSAIDS—ASA, ibuprofen, naproxen ACEIs Opioids Iodine based contrast media 15 Epinephrine 1:1000 subcu or IM initial drug of choice Antihistamines e.g., diphenhydramine Bronchodilator by inhalation, e.g., albuterol High flow oxygen (some exceptions) Systemic corticosteroids 16 Major categories Atrial Blocks Ventricular 17 Supraventricular Originate in the atria Atrial fibrillation is most common SV dysrhythmia Ventricular More serious than atrial dysrhythmias Complete disorganization of contractions Heart block Blockage of electrical conduction system 18 19 20 21 Cardioversion Disrupts cardiac rhythm to “reset” Patient may be awake Defibrillation Uses more joules of shock Patient should not be awake! Implantable cardioverter defibrillators Respond to sensing of dysrhythmias 22 Block flow through ion channels (conduction) Change autonomic activity (automaticity) I Sodium channel blockers II β-blockers III Potassium channel blockers IV Calcium channel blockers 23 Prevent depolarization Action potential slows Ectopic pacemaker activity suppressed Procainamide May produce new dysrhythmias Hypotension 24 Decrease conduction through the AV node Automaticity is reduced Dysrhythmias can be stabilized Propanolol (Inderal) Watch for laryngospasm Bradycardia Serious dysrhythmias Myocardial ischemia 25 Delay repolarization of the myocardial cells Lengthen refractory period Used for serious dysrhythmias Used for atrial and ventricular dysrhythmias Amiodarone May cause new dysrhythmias Hypotension Bradycardia 26 Slow conduction velocity through AV node Reduced automaticity in the heart Slows heart rate Prolongs refractory period Verapamil Myocardial infarction Heart failure May be given continuous IV for up to 24 hours 27 Remember? COPD includes: Chronic bronchitis Emphysema And asthma is off in its own category…. 28 Ventilation is the process of moving air in and out of the lungs Respiration is the exchange of gases due to diffusion Perfusion is the flow of blood through the lungs 29 Bronchospasm Inflammation Asthma 30 Bronchodilators address muscle spasm of the respiratory tree: βadrenergic agonists Anticholinergics Methlyxanthines 31 Activate the sympathetic nervous system (sympathetic = dilation; parasympathetic = constriction) Cause vasodilation Drugs in this category classified as long-acting or shortacting Short-acting referred to as rescue-drugs Long-acting cannot relieve acute bronchospasm! Albuterol (Proventil) Tachycardia Dysrhythmias Hypokalemia Paradoxical bronchospasm 32 Alternative for patients who cannot tolerate β- adrenergic agonists Block the parasympathetic nervous system Prevent vasoconstriction Ipratropium (Atrovent) Headache Cough Dry mouth Paradoxical bronchospasm Pharyngitis 33 Older drugs Long term management of persistent asthma Narrow margin of safety Related to caffeine Theophylline (Theo-Dur) Tremors Tachycardia Dysrhythmias Headache Respiratory arrest 34 Corticosteroids Lelukotriene modifiers Mast cell stabilizers 35 Potent, naturally occurring Allow smooth muscle to become more sensitive to bronchodilation Reduce responsiveness to allergens Used for preventing asthma attacks Beclomethasone (Qvar) Hoarseness Cough, sore throat Oropharyngeal candidiasis 36 Alternative drugs Inhibit release of leukotrienes Edema Inflammation bronchoconstriction Zafirkulast (Acolate) Headache, nausea Throat pain Increased suicidal ideation 37 Inhibit release of histamine from mast cells Taken daily Not effective for acute events Cromolyn (Intal) Sneezing, nasal stinging Throat irritation Angioedema Bronchospasm 38 Many of the same drugs are used with the COPD patient Medications are based on COPD symptoms Bronchodilators Corticosteroids Antibiotics Mucolytics Oxygen 39 β-blockers which cause bronchoconstriction Respiratory depressants (MS, barbiturates) Most importantly…smoking cessation! 40