Anesthesia Flashcards
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Stage 1 Anesthesia
decreased awareness of pain and consciousness, sometimes w/ amnesia
consciousness may be impaired but its not lost
Stage 2 Anesthesia
Disinhibition –> pt is delirious and excited; amnesia
Reflexes are enhanced and respiration is typically irregular
Possible retching and incontinence
Stage 3 Anesthesia
surgical anesthesia:
regular respiration, skeletal muscle relaxation, decrease in eye reflexes and movements, fixed pupils
Loss of motor and autonomic responses to pain; BP is maintained
Stage 4 Anesthesia
Medullary paralysis: depression of respiratory and vasomotor centers
*requires mechanical and pharmacologic support to prevent death
Anesthesiologist job for sure!
Types of General Inhaled Anesthesia
Nitrous oxide, halothane, isoflurane, sevoflurane
Types of General IV Anesthesia
Propofol, etomidate, ketamine, barbiturates
Types of Local Ester Anesthesia
Procaine, Tetracaine
Types of Local Amide Anesthesia
Lidocaine, Bupivacaine
Goals of General Anesthesia
analgesia, unconsciousness/hypnosis, amnesia
Muscle relaxation or immobility (PRN for procedure)
Autonomic and sensory blockade of responses to noxious surgical stimulation
Phases of Anesthesia
Induction
Maintenance
Emergence
General Anesthetic Mechanisms and Effects
Neuronal depression in many regions
Decrease in BP
Respiratory depression
Bronchodilation
Impaired mucociliary clearance
decreased hepatorenal perfusion
Types of Anesthesia
General, Neuraxial (spinal or epidural), peripheral nerve blocks, intravenous regional anesthesia, monitored anesthesia care (MAC), conscious sedation w/out anesthesia personnel
Conscious sedation: how it is administered, pt state
Through IV to make pt sleepy/calm for procedure
**NOT expected to induce impairment of pt respiratory function or ability to maintain their own airway
Pt technically awake but groggy/unable to follow instructions
Conscious sedation Drugs used
periprocedural anesthesia assessment of the patient’s coexisting med conditions and management of actual or anticipated physiological derangements during procedure
MAC: what does it include
administration of sedatives and/or analgesics for conscious sedation (usually)
What is provider focused on during MAC
exclusive and continuously on pt for attendant airway, hemodynamic and physiologic derangements
**must be ready/prepped to covert to general anesthesia AND intervene to rescue pt airway
What is nitrous oxide?
laughing gas; weak anesthesia but good analgesic
**Used a lot as adjuvant
What to give after NO tx
Oxygen
what does pt population does NO not work well in
pt taking opiates
Laughing gas SE
N/V, headache, increased sleepiness, diaphoresis BUT no resp depression
Laughing Gas Contraindications
Respiratory Compromise (ie COPD)
What causes malignant hyperthermia?
Inhaled anesthesia and succinylcholine
Genetic disorder –> caused by mutations of muscle ryanodine receptor leading to uncontrolled release of Ca from the sarcoplasmic reticulum
symptoms of malignant hyperthermia
tachycardia, HTN, severe muscle rigidity, hyperthermia, hyperkalemia, acidosis
CAN BE FATAL!
Tx of malignant hyperthermia
Dantrolene (block Ca release via ryanodine receptor)
Plus cooling, correction of acid-base disturbances
IV Barbiturates Use and Names
Thiopental v. methohexital - redistribution, induction; significant respiratory depression à induction of anesthesia
IV Benzos use and names
*midazolam (Versed®), lorazepam (Ativan®)
*Can be given intranasally; perioperative amnesia, pre-procedure use; amnestic effects
IV Propofol Use and SE
(This slide was not well described)
Induction and maintenance; GABA- A; day surgery (rapid onset and recovery); potent respiratory depression, decreased inotropism, decreased PR, decreased cerebral BP
IV fentanyl Use and SE
Induction and maintenance, conscious and deep sedation; respiratory depression
Ketamine: what is it, Use, who is it used for
NMDA blocker
Use: Dissociative anesthesia (catatonia, amnesia and analgesia without loss of consciousness)
Used in children for short procedure
Ketamine SE
increased HR and CO, increased ICP leading to hallucinations
*not a significant resp depressant
Short Acting Esters for Local anesthesia*
Procaine (Novocaine)
Medium Acting Esters for Local anesthesia*
Cocaine
Long Acting Esters for Local anesthesia*
Tetracaine (more lipophilic)
Medium Acting Amides for Local anesthesia*
Lidocaine (xylocaine)
Long Acting Amides for Local anesthesia*
Bupivacaine (Marcaine)
All local anesthetics do what?*
block Na channels- failure of nerve conduction
Why use adjuvant local anesthetics*
Decrease onset time, Increase duration, increase block intensity, or decrease toxicity
options for adjuvant local anesthetics*
1) Epinephrine (Vasoconstrictor) –> hemostasis
*However, cannot use on certain organs that can easily become ischemic
(Fingers, toes, penis, and nose)
2) Sodium bicarbonate
3) Dexamethasone
