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PHARMACOLOGY Review

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					Paramedic Inter Facility
      Transfer
      Training
    PHARMACOLOGY
        Review
PHARMACOLOGY
Review Quiz
Goals of the Pharmacology Review

• Briefly review information that you
  have already had in your paramedic
  programs.
• The purpose of this program is not to
  teach new concepts of pharmacology
     Medication and Transport

• The most common reason that you will
  be asked to transport a patient utilizing
  the PIFT module will be because the
  patient requires administration or
  monitoring of a medication or
  medications other than those normally
  carried in the paramedic drug box.
    Medication and Transport

• The new PIFT module allows an
  appropriately trained paramedic to
  administer or monitor 18 classes of
  medications, as well as OTC
  medications
Medication and Transport

     Potentially, this could
      involve as many as
        several hundred
     different medications.
This is a significant
 responsibility.
 – Safe, effective transport of patients
   requires sound, fundamental
   knowledge of basic principles of
   pharmacology.
        IMPORTANT
  PHARMACOLOGICAL TERMS
• Antagonism
  – The opposition between 2 or more medications ex.
    narcotics and Naloxone
• Bolus
  – A single, often large dose of a drug. Often the initial
    dose
• Cumulative action
  – An increased effect caused by multiple doses of the
    same drug. Caused by buildup in the blood.
• Hypersensitivity
  – A reaction to a drug that is more profound than
    expected and which often results in an exaggerated
    immune response
• Idiosyncrasy
  – A reaction to a drug that is significantly different from
    what is expected
• Indication
  – The medical condition for which the drug has proven
    therapeutic value
• Parenteral
  – Any route of administration other than the digestive
    tract
• Pharmacodynamics
  – Study of the mechanisms by which drugs act to
    produce biochemical or physiological changes in the
    body
• Pharmacokinetics
  – Study of how drugs enter the body, reach their site of
    action and are eliminated from the body
• Potentiation
  – The enhancement of a drug’s effect by another drug
  – Eg. promethazine may enhance the effect of
    morphine; also alcohol and barbiturates
• Refractory
  – The failure of a patient to respond as expected to a
    certain medication
• Synergism
  – The combined action of 2 or more drugs that is
    greater than the sum of the 2 drugs acting
    independently
• Therapeutic Action
  – The intended action of a drug given in an appropriate
    medical setting
• Therapeutic Threshold
  – The minimum amount of a drug that is required to
    cause the desired response
• Therapeutic Index
  – The difference between the therapeutic threshold and
    the amount of the drug considered to be toxic
  – Often referred to as Safe and Effective range
• Tolerance
  – The decreased sensitivity or response to a
    drug that occurs after repeated doses
  – Increased doses are required to achieve the
    desired effect
• Untoward Effect
  – A side effect of a drug that is harmful to the
    patient
     PHARMACOKINETICS
• Study of the metabolism and action
  of drugs
• Particularly emphasizes the
  following:
   1. Absorption
   2. Distribution
   3. Biotransformation
   4. Excretion
          ABSORPTION

• The movement of a drug from its
  point of entry into the body into
  systemic circulation
            ABSORPTION
• Factors influencing rate of absorption:
    • Drug concentration
    • Site of absorption
    • pH of the drug
       – Acids into acids, etc.
    • Status of circulation
    • Solubility
       – Water based vs. oil based
        DISTRIBUTION

• The manner in which a drug is
  transported from the site of
  absorption to the site of action
          DISTRIBUTION

• Influenced by several factors:
    • Cardiovascular function
      –HR, BP, EF
    • Physical barriers
      –Blood-brain and placenta barriers
    BIOTRANSFORMATION

• The process by which drugs are
  inactivated and transformed into a
  form that can be eliminated from
  the body
    BIOTRANSFORMATION
• Inactive forms are called metabolites
• Rate of transformation will determine
  how often a drug must be administered
  – Eg. Epinephrine transforms in 3-5 minutes
• The liver is the most significant organ
  in the transformation process
        EXCRETION

• The process of eliminating
  drugs from the body
            EXCRETION

• Primarily accomplished through the
  kidneys but may also involve the liver,
  the lungs, intestines, sweat and
  mammary glands
  PHARMACODYNAMICS

How a drug works and how we
    can expect the body to
 respond to the administration
           of a drug
    PHARMACODYNAMICS
• Most drugs work through interactions
  with receptor sites.
  – These are protein coatings found on the outer
    surface of the cell membrane.
  – Generally, when a drug binds or attaches to a
    receptor site, a chemical reaction occurs that
    initiates the desired physiological or
    therapeutic response.
  – Such drugs are called agonists.
Some drugs work through the
principle of antagonism
– In such cases, a drug competes with
  another drug or chemical for position at a
  receptor site.
– We see this with Naloxone which competes
  with narcotic drugs
  • In this case Naloxone would be an antagonist.
AUTONOMIC NERVOUS SYSTEM
• The Peripheral nervous system is divided
  into afferent and efferent divisions.
• The section of the efferent division that
  controls involuntary bodily functions is
  known as the Autonomic Nervous System.
• These functions include cardiac function,
  body temperature, smooth muscle, gland
  function and arterial blood pressure.
AUTONOMIC NERVOUS SYSTEM

  • Sympathetic nervous system
  • Parasympathetic nervous system
SYMPATHETIC NERVOUS SYSTEM

• Prepares body to deal with stress
  – Fight or flight response
• Neurotransmitters are epinephrine and
  norepinephrine
  – Chemical substances that facilitate
    excitation or inhibition of target cells
• A drug that stimulates the sympathetic
  nervous system is known as a
  sympathomimetic or adrenergic agent

• A drug that inhibits the sympathetic
  nervous system is called a
  sympatholytic or anti-adrenergic agent
• Ex. Propanolol ( beta blocker )
PARASYMPATHETIC NERVOUS SYSTEM

• Controls vegetative functions
  – Constriction of pupils, slowing of heart rate,
    constriction of bronchioles, etc.
• Neurotransmitter is Acetylcholine
• A drug that stimulates the system is called a
  Parasympathomimetic or cholinergic drug
  – Eg. Prostigmine
• A drug that blocks or inhibits the system is
  called a Parasympatholytic or anticholinergic
  drug
  – Eg. Atropine
Classifications of Medications
  • Anticoagulants      • GI Agents
  • Anticonvulsants     • IV fluids
  • Antidiabetics       • Narcotics
  • Antidysrhythmics    • Parenteral Nutrition
  • Antihypertensives   • Platelet Aggregation
                          Inhibitors
  • Anti-infectives
                        • Respiratory Medications
  • Antipsychotics      • Sedatives
  • Cardiac             • Vasoactive agents
    Glycosides
  • Corticosteroids
  • Drotrecogin
     GENERAL CONCEPTS
• Check transfer order carefully to be sure
  that all medications ordered are permitted
  under the PIFT program.
• Be sure that order specifies:
  – Dosage information
  – Times of administration (where applicable)
  – Indications for changes or discontinuance.
  – Eg. Nitroglycerin dosage is often altered
    based on pain and/or BP.
     GENERAL CONCEPTS

• Ask the physician or RN to review
  medication if it is one that you are not
  familiar with.
  – Discuss potential adverse reactions and
    how to deal with them.
  – Use resources to double check
     GENERAL CONCEPTS

• Determine how long it will take to
  reach receiving facility and calculate
  the amount of the drug you will need
  to reach your destination.
  – Allow for unforeseen delays.
     GENERAL CONCEPTS

• Check to be sure that you have the
  right drug and the right concentration.
• Check expiration dates of all
  medications.
     GENERAL CONCEPTS
• Be sure that you thoroughly
  understand how to use the infusion
  pump being supplied by the hospital
  – Are you able to troubleshoot potential
    problems?
• Check IV site for patency, redness,
  etc.
     GENERAL CONCEPTS
• Be sure to have a drug reference book
  available in your ambulance
• Review drug reference for detailed
  information about the drug.
  – Review side effects, adverse reactions,
    dosing, interactions, etc.
• Contact medical control if it becomes
  necessary to administer another drug to
  ascertain possible interaction problems