the study of medications and their actions including drug origins, properties and uses. (pg. 204)
agonistic interaction occurs when a drug potentiates or enhances the effect of another substance.
Ex: synergists and additives
Synergists act in combination to produce a stronger or more powerful effect than would be demonstrated if each agent was administed individually.
Medication additives alter some aspect of the action of the original agent.
Example: adding epinephrine to lidocaine
an AGONIST is a medication that binds to a specific receptor site in the body, producing an alteration in biological function and resulting in a desired effect.
-an ANTAGONIST binds to the agonist's receptor site, preventing the agonist from binding there and causing it's desired effect.
(Basically, it is a drug that reverses the effects of another drug)
listing of medical conditions that the medication is know to treat
list of circumstances or medical conditions under which the medication should not be used
Onset: effects of meds begin showing
Peak: effects of meds at peak
the concentration or dose of a medication used to produce the desired result without producing a harmful effect
an expected, undesirable, but tolerable effect of a medication.
(ex: dry mouth, constipation, diarrhea, dizziness or drowsiness)
an undesirable and potential harmful effect of a medication that can lead to organ damage or failure.
reduction in the effect of a medication given at the same dose over a period of time
term to describe entire process of a drug within the body.
involves the transport of the medication within the body once it enters the circulatory system
the effect of medication in the body continues until it is biotransformed or excreted.
Kidneys partially responsible for the filtration of medications
the concentration of a medication is the ratio of solute to solvent. The two components of a solution
4 stages of General Anesthesia
Stage 1: amnesia stage
Stage 2: delirium stage (excitement)
Stage 3: surgical anesthesia stage
Stage 4: overdosage stage
4 Phases of General anesthesia
Emergence phase (hearing is the last thing to go)
Drug Handling Techniques: pg 212
6 basic rights for correct drug handling
1. The right patient
2. The right drug
3. The right dose
4. The right route of administration
5. The right time and frequency
6. The right documentation, including labeling
-performed to reduce the risk of aspiration.
-applied prior to induction of anesthesia and continue until the endotracheal tube is placed.
-employed in the OR in situations where the patient requires emergency surgery shortly after eating. or the NPO status is not verified, or GI bleeding
Laryngospasm and Bronchospasm
-reactions demonstrated by the lightly anesthetized patient.
-a slight trigger of the "gag" reflex results in a spasm or rigidity of the upper respiratory tract....resulting in an inability of the air and waste gases to move in and out of the lungs.
-TRIGGERED BY SALIVA IN THE BACK OF THE THROAT
-SUCCINYLOCHOLINE = drug, neuromuscular blocker - relaxes spasm
(can cause Malignant Hyperthermia)
(drug, SUCCINYLCHOLINE can cause this and
Halogenated inhalation agents such as...
(desflurane, isoflurane, sevoflurane)
MUSCLE RIGIDITY -
The skeletal muscles are stimulated to contract, but due to the inability of calcium to release, the muscles cannot relax, resulting in rigidity, heat generation, and a buildup of lactic acid and carbon dioxide.
-genetically transmitted disease seen more in males
unexplained tachycardia (increase in heart rate), followed by tachypnea and an increased level of carbon dioxide.
Late sign: rise of temperature, as high as 107 degrees
-If it occurs, stop and give 100% oxygen
-MH cart on standby
(designated for Malignant Hyperthermia, with supplies readily available)
-Dantrolene is the only phamacological agent for the treatment of MH, mixed with sterile water, given IV
dextrose and insulin,
furosemide or mannitol
- chilled IV fluids of saline dextrose (to regulate temp)
-chilled saline lavage - for body cavities
Drugs used during MH crisis
to assist in metabolic and respiratory acidosis regulation
dextrose and insulin:
to provide available glucose to the cells to maintain cellular metabolism
furosemide or mannitol:
to promote renal clearance of waste products
to prevent intravascular clot formation
Only pharmacological agent for the treatment of MH
-mixed with sterile water
ANTAGONIST for MH (reverses)
Anesthetic agents that are inhaled and pass into the bloodstream via pulmonary function.
-not an anesthetic agent
-essential for survival of the patient...promotes respiration and cellular function
-clear, colorless, fruity odor
-only true gas still in use
-interacts with the cellular membrane of the CNS to produce ANALGESIA with some amnesia.
-eliminated by exhalation
-used in conjunction of other anesthetic agents (not strong enough alone)
- CONTRAINDICATING its use during some surgical interventions such as tympanoplasty
-may contribute to postoperative nausea and vomiting.
Primarily hormones are derived form animal sources including human sources.
-Cows - bovine
-pigs - porcine
manufactured in a laboratory.
begin with a natural substance which is then chemically altered.
-aminoglycoside group of antibiotics
recombinant DNA technology
"recombinant DNA technology"
-DNA is artificially constructed by introducing foreign DNA into the DNA of a specific organism - daughter cell created
Hepatitis B vaccine
3 Legal Drug Classifications
drugs with a high potential to cause psychologigical and or physical dependence and abuse.
(labeled classes 1 - 4)
medications that are prescribed but if used inappropriately, could cause significant harm to the patient
Over the Counter Medications
pharmacologic agents that are prepared in a dosage that are generally safe to administer without the direction of a physician
(ends in "ane" = can trigger MH)
drugs that are in liquid form - potent vapors are inhaled to cause effects
-sevolfurane, desflurane, isoflurane
less commonly used: enflurane and halothane
Rapid and smooth onset and recovery
ideal agent for both adult and pediatric inhalation induction
Disadvantages: causes bradycardia, hypotension, cardiac dysrhythmias and reduces cardia output
-may also cause nausea and vomiting in the postoperative period.
-requires the use of a heated vaporizer
It has a pungent aroma, CONTRAINDICATING its use during inhalation induction.
-Rapid onset and recovery
-not biotransformed in the liver, it is safe to use for patients with hepatic insufficiency
-Less expensive than sevoflurane
-causes nausea and vomiting like sevoflurane
pungent, musty smelling
-rapid induction and recovery
-potentiates neuromuscular blockade
-may cause hypotension
-increases intracranial pressure (ICP), which is reversible with hyperventalation
Intravenous Agents I.V.
-neuromuscular blocking agents
antimuscarinic (anticholinergic) agents
Induction agents (IV)
permit a rapid and pleasant transition from consciousness (Stage 1) to unconsciousness (Stage 3) by quickly passing through the delirium stage (Stage 2)
-Side effects: Hypotension and respiratory depression
- may also be used during maintenance of general anesthesia
Drugs: Propofol, Etomidate, Thiopental sodium, Methohexital sodium
"Milk of amnesia"
-discarded within 6 hrs of opening
-irritating to the vein and may cause patient discomfort at the IV site
(Lidocaine given IV just prior to propofol inj. may ease that discomfort)
-Rapid induction and emergence without the prolonged "hangover" effect
-CONTRAINDICATED: for patients with unstable hemodynamics or head trauma.
nonbarbiturate hypnotic agent used for anesthesia induction
-similar to propofol, but does not produce analgesia
INDICATED: choice for anesthesia induction of the hemodynamically unstable patient indications
COMPLICATION - postoperative nausea and vomiting (POVN) as well as adreanal suppression are seem more frequently in patients given etomidate
-short- acting potent barbiturate
-does NOT provide anesthesia or muscle relaxation
-has hypnotic, amnesic, and sedative effects.
-Leaves patient with a residual hangover effect lasting through and prolonging the patient's emergence and recovery phases.
-marked respiratory and circulatory depression immediately following injection, non flammability, inability to cause irritation to the respiratory tree, and lack of salivary stimulation
-Helps reduce Laryngospasm and Bronchospasm due to decreasing saliva
-minor patient stimulation during the lighter stages of anesthesia administration, which may cause laryngospasm, and the alkaline nature of the drug, which may be locally irritating to the vein.
selectively interrupt the associative pathways of the brain. Patients may appear wide awake, yet they are unaware of their surroundings.
-Produce amnesia and profound analgesia.
-Ketamine hydrochloride (Ketalar)
-most commonly used dissociative agent.
-administered IM or IV
-production of vivid imagery and morbid hallucinations during administration and recovery.
-limited use to children 2 - 10 years old.
produces amnesia and analgesia while patient is wide awake
Contraindication: triggers laryngospasm due to SALIVA INCREASE
CLASS II controlled substances
-not handled by CSTs
-narcotics classified as analgesics = sedation
-Morphine sulfate, meperidine, fentanyl citrate, sufentanil citrate, alfentinal hydrochloride, remifentanil hydrochloride,
used for the control of severe pain.
-given IM = preoperative sedative/analgesic
-postoperative = analgesic
iv - anesthetic agent
-intrathecally - spinal pain control
side effects. bradycardia (slow heart), hypotension, vasodialation, nausea, vomiting, confusion, respiratory depression
similar to morphine
-used to treat moderate to severe pain
DISADVANTAGES: side effects.
increased ICP, tachycardia and vasodilaton (causes Malignant Hyperthermia)
RAPID ONSET, SHORT DURATION (on test)
the first of the synthetic narcotic analgesics to be used for anesthesia administration.
-use with patients with myasthenia gravis is contraindicated
similar to fentanyl, but five times more potent
-has a rapid onset of action when given IV
-It has a short duration of activity and is rapidly eliminated
similar in action and usage to fentanyl
-short acting analgesic
Disadvantage: induced respiratory depression may outlast the analgesic effect produced
short duration. 5 -10 min.
synthetic opiod metabolized in blood and muscle tissue.
DISADVANTAGE: may cause respiratory depression, brady cardia, hypotension, and muscle rigidity.
ADVANTAGE: short duration, allows more accurate dose titration (method of estimating amount of solution)
(pg. 232, important)
The opioid effect can be antagonized or reversed by the administration of
naloxone hydrochloride (Narcan)
-to reduce the anxiety and apprehension of the preoperative patient
-as an adjunct to general anesthesia to reduce the amount and concentration of anther more potent agents
(Diazepam, Midazolam, Droperidol)
CLASS 4 controlled substance
-primary anesthetic use is to reduce ANXIETY and provide some skeletal muscle relaxation.
-provides retrograde amnesia of short duration.
-5 -15 min = onset of action
-rapid onset and short acting
-ideal for patients undergoing outpatient procedures
-short duration memory impairment
-twice as potent as diazepam
-IV dosage is diluted with injectable dextrose/water/saline
Droperidol premixed with fentanyl citrate
trade name: INNOVAR
-provides a combination of sedation and analgesia
Amino Amide Group
drugs in this group are metabolized in the liver and excreted by the kidneys and include:
-lidocaine, mepivicane, bupivacain, etidocain