chapter 18 General Anesthesia
Terms in this set (29)
how does general anesthesia effect the CNS?
~Motor and ANS is inhibited
~Dilation of cerebral blood vessels
~Change in intracranial pressure
how does general anesthesia effect the Cardiovascular system?
~depression of myocardium and blood pressure
~heart rate increases
~increase in O2 consumption of the myocardium
how does general anesthesia effect the skeletal system?
~less reflux conduction near muscle incision and movement
~interuption of excessive contractions
~propofol: does not potentiate neuromuscular blockade
Ketamine: increases skeletal muscle tone
how does general anesthesia effect the respiratory system?
~depressed by most anesthetics (except ketamine)
~irritation fo respiratory lining causing cough, increased mucous, laryngospasms
how does general anesthesia effect the hepatic and renal systems?
~IV anesthetics metabolized by liver
~Voltile anesthetics temporarily reduce renal and hepatic blood flow, glomerular filtration and urine output
~hepatitis can be associated with volatile anesthetics
what is general anesthesia?
produces unconsciousness to prevent painful stimulation during surgical and dental procedures
what are the stages of general anesthesia?
Stage 1 - loss of pain -MILD SEDATION cerebral cortex inhibited, unconsciousness
Stage 2 - excitement and hyperactivity -
Stage 3 - surgical anesthesia, stage surgery begins and remains until procedure ends - SURGERY BE PERFORMED
Stage 4 - paralysis of medulla, avoid this stage
what is monitored sedation?
IV, followed by propofol, fentanyl, medical personnel watches through surgery and recovery
what is general anesthesia?
produce unconsciousness to prevent painful stimulation during surgical and dental procedures, no memory of surgical procedure
what is balanced anesthesia?
more than one anesthetic plus muscle relaxants plus anti anxiety drugs, so each drug complements action of anesthetics, so CNS depression is less; less concentrated side effects
what is induction?
time took to go from consciousness to stage 3
what is maintenance?
keeping a patient safely in stage 3
what is the MOA with general anesthesia?
interact with membrane ion channels inhibiting Cl-, Na+, potassium, All of them are CNS depressants
~Bind with GABA, chloride, hyper polarized (inhibitory)
~Inhibits excitatory neurotransmitter NMDA blocks cation movement and depolarization
What are some examples of inhalation gases and volatile liquids?
route: facemask, laryngeal mask airway, trach tube
~ketamine (no muscular relaxation)
~barbiturates (rapid induction)
route: Entirely IV throughout
what do anesthetics do at low doses?
relieve anxiety and produce relaxation
are other tissues besides the brain influenced with anesthesia?
what does a neuromuscular block do?
Blocks acetylcholine receptors on motor neurons for muscle relaxation, intubation, or endoscopy's
what are two of the most popular NMB drugs?
Where are four examples of regional anesthesia?
what is dissociative anesthesia?
causes amnesia (can't remember), skeletal muscles don't relax, look conscious
what is Neouroleptanalgesia?
no pain, patient is conscious, it is a narcotic plus a tranquilizer together
What is Neuroleptanesthesia?
anesthesia where the patient is unconscious with larger doses (tubing)
What is MAC?
A few different agents of anesthesia together
why is preanesthetic and post anesthetics given?
~aid in induction
~counteract side effects of anesthesia
~make recovery safe and more comfortable
antiemetics: reduce nausea
Cholinergic: relieve urinary retention
for what specific reasons would a patient need monitored while under anesthesia?
Why would Propofol take special attention?
must be septic. bc it can grow bacteria, and used with caution for lipid metabolism disorders
What is the most used anesthetic?
what is the top choice for volatile anesthetics?