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Paramedic Care: Principles & Practice Volume 1 Introduction to Advanced Prehospital Care. Chapter 9 General Principles of Pharmacology. Chapter 9, Part 1 Basic Pharmacology. Part 1 Topics . General Aspects Legal Aspects Drug Research and Development Patient Care Using Medications
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Paramedic Care:Principles & Practice Volume 1Introduction to Advanced Prehospital Care
Part 1 Topics • General Aspects • Legal Aspects • Drug Research and Development • Patient Care Using Medications • Pharmacology
Introduction • The use of herbs and minerals to treat the sick and injured has been documented as long ago as 2000 BC. • Presently, the Food and Drug Administration (FDA) is allowing many previously prescription-only drugs to become available over the counter. • Growing consumer awareness in health care • Consumer marketing by the pharmaceutical industry
General Aspects • Drugs are chemicals used to diagnose, treat, or prevent disease. • Pharmacology is the study of drugs and their actions on the body. • Health care professionals have a systematic method for naming drugs.
Drug Names • Chemical • States its chemical composition and molecular structure • Generic • Usually suggested by the manufacturer • Official • As listed in the U.S. Pharmacopeia • Brand • The trade or proprietary name
Sources of Drug Products • Four main sources of drugs are: • Plants • The oldest source of medications • Purple foxglove • Animals • Extracts of bovine (cow) and porcine (pig) pancreas • Minerals • Inorganic sources of drugs such as calcium chloride • Synthetic • Created in the laboratory
Reference Material • United States Pharmacopeia (USP) • Physician’s Desk Reference (PDR) • Drug Information • Monthly Prescribing Reference • AMA Drug Evaluation • EMS field guides
Components of a Drug Profile • Names • Most frequently include generic and trade names • Classification • The broad group to which a drug belongs • Mechanism of Action • The way in which a drug causes its effects
Components of a Drug Profile • Indications • Conditions that enable the appropriate administration of the drug • Pharmacokinetics • How the drug is absorbed, distributed, and eliminated • Side Effects/Adverse Reactions • The drug’s untoward or undesired effects
Components of a Drug Profile • Routes of Administration • How the drug is given • Contraindications • Conditions that make it inappropriate to give the drug • Dosage • Amount of the drug that should be given
Components of a Drug Profile • How Supplied • Includes the common concentration of the available preparations • Special Considerations • Pediatric, geriatric, or pregnant patients
Legal Aspects • It is important to know and obey the laws and regulations governing medications and their administration. • These include federal, state, and agency regulations.
Federal • Pure Food and Drug Act of 1906 • Harrison Narcotic Act of 1914 • Federal Food, Drug, and CosmeticAct of 1938 • Comprehensive Drug AbusePrevention and Control Act of 1970
State and Local Standards • State • State laws vary widely. • Some states have legislated which medications are appropriate • Others have left those decisions to local control • The medical director can delegate to paramedics the authority to administer medications.
State and Local Standards • Local • Local leaders are responsible for ensuring public safety. • EMS agencies have the responsibility to create local policies and procedures to ensure the public well-being.
Drug Standards • Standardization of drugs is a necessity • Assay • Determines the amount and purity of a given chemical in a preparation in the laboratory • Bioequivalence • Relative therapeutic effectiveness of chemically equivalent drugs
Drug Research and Development • Initial drug testing begins with the study of both male and female mammals. • Pharmacokinetics tested in animals • Progresses to human testing
Patient Care Using Medications • Know the precautions and contraindications for all medications you administer • Practice proper technique • Know how to observe and document drug effects
Patient Care Using Medications • Maintain a current knowledge inpharmacology • Establish and maintain professionalrelationships with other health care providers • Understand pharmacokinetics andpharmacodynamics
Patient Care Using Medications • Have current medication referencesavailable • Take careful drug histories including: • Name, strength, dose of prescribed medications • Over-the-counter drugs • Vitamins • Herbal medications • Allergies
Patient Care Using Medications • Evaluate the patient’s compliance, dosage, and adverse reactions • Consult with medical direction as needed
The 6 Rights of Medication Administration • Right medication • Right dosage • Right time • Right route • Right patient • Right documentation
Special Considerations • Pregnant patients • Pediatric patients • Geriatric patients
Pregnant Patients • Ask the patient if there is a possibility that she could be pregnant. • Some drugs may have an adverse effect on the fetus of a pregnant female. • A drug’s possible benefits to the mother must clearly outweigh its potential risks to the fetus.
Pregnant Patients • The FDA has developed the classification system for the administration of drugs to a pregnant patient. • Consult medical direction.
Pediatric Patients • Several physiological factors affect pharmacokinetics in newborns and young children. • Children up to one year old have diminished plasma protein concentrations. • Drugs that bind to proteins have higher free drug availability.
Pediatric Patients • A higher amount of total body water means a greater volume and may require higher drug doses. • The newborn’s metabolic rates may be much lower than an adult’s • Rise rapidly in the first few years.
Pediatric Patients • Pediatric drug dosages must be individualized to minimize the risks of toxicity. • The Broselow tape
Geriatric Patients • Significant changes in pharmacokinetics may also occur in patients older than about 60 years. • Decreased gastrointestinal motility • Decreased plasma proteins • Body fat increases and muscle mass decreases with age • Multiple medications or to have multiple underlying disease processes
Pharmacology • The study of drugs and their interactions with the body. • Drugs may be given for their local action or for systemic action. • Two major divisions: • Pharmacokinetics • Pharmacodynamics
Pharmacokinetics • Review of Transport • Active transport • Requires energy or ATP • Facilitated diffusion • Carrier-mediated protein • Passive transport • Osmosis and diffusion • Filtration
Drug Absorption • Several factors affect a drug’s absorption: • Route given • Perfusion of tissue • Solubility • Ionization and Ph • Absorbing surface • Concentration of drug • Bioavailability refers to drug available at tissue level
Distribution • Most drugs will pass from bloodstream to target tissues. • Some proteins bind drugs for a prolonged time. • Only unbound drugs can cross the cell membrane. • Changing the pH of blood may affect protein binding. • Increasing pH enhances TCA binding.
Distribution • Certain organs exclude some drugs from distribution. • Blood-brain barrier • Only non-protein bound, lipid-soluble drugs may exit CNS vasculature. • Placental barrier • Restricts drug delivery to fetus • Other stores • Fats • Specific tissues
Biotransformation • The metabolism of drugs is called biotransformation. • Effects of biotransformation: • Can transform the drug into a more or less active metabolite • Can make the drug more water soluble (or less lipid soluble) to facilitate elimination
Biotransformation • Many biotransformation processes occur in the liver. • First-pass effect • The first pass through the liver may partially or completely inactivate many drugs. • Microsomal enzymes • Phase I • Phase II
Drug Elimination • Most drugs (toxins and metabolites) are excreted in the urine. • Renal excretion methods • Glomuler filtration • Function of glomerular filtration pressure • Results from blood pressure and blood flow • Tubular secretion • Active transport pumps in proximal tubule
Drug Routes • How a drug is given has an impact on absorption and distribution. • Routes • Enteral • Absorption through the gastrointestinal tract • Parenteral • Any area outside of the gastrointestinal tract
Enteral Drug Administration • Oral (PO) • Oro/nasogastric (OG/NG) • Sublingual (SL) • Buccal • Rectal (PR)
Intravenous (IV) Endotracheal (ET) Intraosseous (IO) Umbilical Intramuscular (IM) Subcutaneous (SC) Inhalation/Nebulized Topical Transdermal Nasal Instillation Intradermal Parenteral Drug Administration
Drug Forms • Solid forms: • Pills, powders, suppositories, capsules • Liquid forms: • Solutions, tinctures, suspensions, emulsions, spirits, elixirs, syrups
Solid Forms • Pills • Drugs shaped spherically to be swallowed • Powders • Not as popular as they once were • Tablets • Powders compressed into disk-like form • Suppositories • Drugs mixed with a waxlike base that melts at body temperature • Capsules • Gelatin containers filled with powders or tiny pills