Pain Management & Pharmacology

Pain

• Substance P is a neurotransmitter involved in transmitting pain signals
• Gate theory suggests the spinal cord can either block or allow pain transmission
• Opioid receptors, including Mu, Kappa, and Delta, modulate pain

Drug Dependency/Tolerance/Addiction

• Physiological or psychological adaptation can occur with opioid use

Methadone Treatment

• Helps reduce withdrawal symptoms experienced during opioid addiction

Opioid Analgesics

• Bind to opioid receptors to block pain
• Examples include Morphine, Hydromorphone (Dilaudid), Oxycodone (OxyContin), and Fentanyl

Opioid Antagonists

• Reverse opioid effects
• Naloxone (Narcan) is an example

NSAIDs

• Inhibit COX enzymes to reduce pain and inflammation
• Examples include Ibuprofen (Advil), Naproxen (Aleve), and Aspirin

Acetaminophen

• Inhibits prostaglandin synthesis
• Helps reduce pain, but not inflammation
• Tylenol is an example

Hypertension

• Primary hypertension has no clear cause, while secondary hypertension results from another condition
• Systolic/diastolic blood pressure reflects the pressure during contraction/relaxation of the heart
• Hypertensive crisis is indicated by BP >180/120 and requires immediate treatment
• The RAAS system regulates blood pressure using angiotensin and aldosterone

Diuretics

• Decrease blood volume
• Furosemide (Lasix) is a loop diuretic
• Hydrochlorothiazide (HCTZ) is a thiazide diuretic
• Spironolactone (Aldactone) is a potassium-sparing diuretic

Calcium Channel Blockers

• Reduce vascular resistance
• Verapamil is a cardioselective calcium channel blocker
• Amlodipine (Norvasc) is an arterioselective calcium channel blocker

ACE Inhibitors

• Block angiotensin conversion
• Examples include Lisinopril and Enalapril

Beta Blockers

• Reduce cardiac workload
• Examples include Metoprolol and Atenolol

Alpha 1 Blockers

• Promote vasodilation
• Doxazosin (Cardura) is an example

Alpha 2 Agonists

• Reduce sympathetic output
• Clonidine is an example

Direct Vasodilators

• Relax blood vessels
• Hydralazine is an example

Angina, MI, CVA

• CAD/Atherosclerosis involves the narrowing of coronary arteries
• Angina can be stable (predictable) or unstable (emergency)
• Myocardial infarction (MI) involves a blockage of a coronary artery
• Cerebrovascular accident (CVA) can be ischemic (clot) or hemorrhagic (bleed)
• Preload and afterload refer to blood volume and resistance which effects heart workload

Organic Nitrates

• Reduce preload through vasodilation
• Nitroglycerin and Isosorbide are examples

Beta Blockers

• Reduce heart rate and oxygen demand
• Metoprolol and Propranolol are examples

Calcium Channel Blockers

• Relax coronary arteries
• Diltiazem and Amlodipine are examples

Anticoagulants

• Prevent clot formation
• Examples include ASA (Aspirin), Warfarin (Coumadin), and Enoxaparin (Lovenox)

Thrombolytics

• Dissolve existing clots
• Alteplase (tPA) is an example

Heart Failure

• Left-sided heart failure affects the lungs, while right-sided heart failure affects the body
• Inotropic and chronotropic factors affect contractility and heart rate
• Preload and afterload reduction can reduce heart strain by controlling volume and resistance
• Goals include reducing workload, improving function, and preventing fluid overload

ACE Inhibitors

• Decrease afterload and preload
• Lisinopril and Captopril are examples

Beta Blockers

• Reduce heart rate and contractility
• Carvedilol and Metoprolol are examples

Beta 1 Agonists

• Increase contractility
• Dobutamine is an example

Vasodilators

• Reduce preload and afterload
• Isosorbide Dinitrate is an example

Cardiac Glycosides

• Improve contractility
• Digoxin is an example

Diuretics

• Remove excess fluid
• Furosemide (Lasix) and Spironolactone are examples

PDE III Inhibitors

• Increase contractility
• Milrinone is an example

Dysrhythmias

• ECG basics involve P wave, QRS, and T wave, representing the cardiac cycle
• Tachycardias are fast rhythms, while bradycardias are slow rhythms
• Therapeutic goals are to terminate and prevent recurrence

Class I Sodium Channel Blockers

• Slow conduction
• IA: Quinidine, Procainamide
• IB: Lidocaine

Class II Beta Blockers

• Reduce heart rate and excitability
• Propranolol, Metoprolol are examples

Class III Potassium Channel Blockers

• Prolong repolarization
• Amiodarone is an example

Class IV Calcium Channel Blockers

• Slow AV conduction
• Diltiazem, Verapamil, are examples

Diabetes

• Type 1 diabetes is autoimmune, while Type 2 involves insulin resistance
• DKA is severe hyperglycemia with ketone production
• Complications include microvascular (retinopathy) vs. macrovascular (CAD, stroke) issues

Insulin

• Rapid-Acting: Lispro (Humalog), Aspart (Novolog)
• Short-Acting: Regular insulin (Humulin R)
• Intermediate-Acting: NPH (Humulin N)
• Long-Acting: Glargine (Lantus), Detemir (Levemir)

Sulfonylureas

• Stimulate insulin secretion
• Glyburide, Glipizide are examples

Meglitinides

• Rapid insulin release
• Repaglinide (Prandin) is an example

Biguanides

• Reduce glucose production
• Metformin is an example

Thiazolidinediones

• Increase insulin sensitivity
• Rosiglitazone (Avandia) is an example

Alpha-Glucosidase Inhibitors

• Delay carbohydrate absorption
• Acarbose is an example

Incretin Enhancers

• Increase insulin secretion
• Exenatide (Byetta), Sitagliptin (Januvia) are examples