Pharmacology of general Anesthetics Flashcards
What are the 4 functional components of General anesthetics for surgery?
- Analgesia
- Amnesia
- Inhibition of sensory and autonomic reflexes
- decreased skeletal muscle tone
What are 3 components of conscious sedation?
- analgesia
- Amnesia
- retained responsiveness to verbal commands
Which stage of General anesthesia?
Analgesia followed by amnesia without a loss of consciousness
Stage 1
Which stage of General anesthesia?
Pt is unconscious and amnestic
pupillary dilation
BP and respiration are irregular
agitation, delirium, retching, vomiting, involuntary limb movement, breath-holding are common
Stage 2: excitation
Which stage of general anesthesia?
painful stimulation does not elicit somatic reflexes or deleterious autonomic reflexes
patient is unconscious - central gaze, constricted pupils
slow and regular respiration
Stage 3: surgical anesthesia
Which stage of general anesthesia?
dose-dependent depression of blood pressure and spontaneous respiration
respiratory support is needed
Stage 4: medullary depression
What is MAC50?
Measure of potency:
Minimum Alveolar Concentration producing immobility to a standard noxious stimulus in 50% of patients
What are factors that affect the onset of action of anesthetics?
Minute ventilation
Pulmonary Blood flow
Brain blood flow
Which type of anesthesias have the fastest and slowest rate of equilibrium?
(onset of action)
fast: poor water solubility
slow: high water solubility
What determines the potency of an anesthetic
lipid solubility
What is the primary elimination of anesthesia?
expiration
What are two adverse effects of Halothane
Hepatitis (Enflurane lacks liver toxicity)
Sensitizes heart to lethal ventricular arrhythmias
—prevented by B-blockers
What is a metabolism side effect of fluoride “-flurane”?
Diabetes Insipidus
What are side fx of volatile anesthetics?
Decreased CO2 drive to breathe Decreased glomerular filtration Increased cerebral blood flow/pressure Reduced skeletal muscle tone Malignant Hyperthermia - use DANTROLENE
What is nitrous oxide used for? why??
Dental procedures
- good amnestic, good analgesic
- minimal cardio/resp depression
- Rapid onset, rapid offset
