General And Local Anesthetics Dr. Kruse Flashcards
Inhaled anesthetics ending and 6 of them
Desflurane Enflurane Halothane Isoflurane Sevoflurane Nitrous Oxide
IV Anesthetics 6
- Diazepam
- Etomidate
- Fentanyl
- Ketamine
- Midazolam
- Propofol
Local Anesthetics 6 and ending
Benzocaine Bupivacaine Cocaine Dibucaine Lidocaine Procaine
5 desired effects from an anesthetic
- unconsciousness
- Amnesia
- Analgesia
- Attenuation of autonomic reflex to noxious stimulation
- immobility in response to noxious stimulation (skeletal muscle relaxer)
= need more the 1 to achieve all 5
inhibitory channels of anesthetics
exictatory channels of anesthetics
- GABA (Cl- channels) , K+ channels
2. NMDA, AchR, 5HT, AMPA
key to how quickly an inhaled anesthetic gets into CNS and causes changes
the SLOWER the rate of absorption into BLOOD + concentration making it into the alveoli
blood:gas partition
a drugs affinity for blood over inspired gas (higher the higher blood solubility and the lower concentration makes it to cns)
SMALL blood:gas
what happens and 2 drugs
gas reaches a HIGH arterial P in alveoli Fast = Fast acting and Fast leaving = A lot makes it to brain 1. NO 2. Desflurane
BIG blood:gas
what happens and 1 drug
high arterial P in alveoli is reached slowly
= Slow to get to CNS and slow to leave
1. Halothane
MAC (Minilam Alveolar Concentration)
amount that a drug is needed to be inhaled that works in 50% of subjects during surgery
(most are over 100% = you need to combine more then 1 drug for good surgery anesthesia)
Toxicity of inhaled anesthesia
- common
- Halothane
- in combination with succinylcholine , and how to fix
- drugs giving F ions
- N, V
- Hepatitis, (2days to 3 weeks later)
- Malignant Hyperthermia (htn, tachy, muscle rigid + rhabdo, acidosis, hyperthermia) = TREAT WITH DANTROLENE
- kidney problems
how to reverse malignant hyperthermia
DANTROLENE
IV anesthetics are different how 3 things (biochema and R is likes)
PREFERRED MOST
lipophilic = QUICK ONSET
(most act on GABA)
Midazolam effects can be reversed with
Flumazenil
(slow onset slow recovery)
Fentanyl effects can be reversed with
Naloxone
slow onset slow recovery
Propofol
GABA
FAST onset + SHORT acting (3-10min)
(continuous infusion can last more hours = in ICU or operating room)
Propofol side effects
hypotension
respiratory depressant
Fospropofol
water soluble so similar to propofol only LONGER recovery and SLOWER onset (less pain when administrating it)
Etomidate
GABA
FAST and longer then propofol recovery (continuous infusion only works before 4-8hours)
= minimal cardiovascular and respiratory depression so good for CV or Pulmonary PATIENTS**
Etomidate adverse effects
inhibits cholesterol ā> cortisol (11B-hydroxylase)
Ketamine
NMDA agonist (PCP structure) can cause upleasant emergence reactions (vivid colorful dreams, hallucinations, out-of-body experiences)
Dexmedetomidine
A2 adrenergic agonist = hypnosis (SLEEP LIKE STATE) by binding to A2 R at locus ceruleus
(SHORT time for ICU intubated or ventilated patients, or added to adjunct)
2 anesthesia ADJUNCTS
- Opioids : Fentanyl, Sufentanil, Remifentanil, Morphine
- Barbiturates : increase GABA, Thiopental, Methohexital
- Benzodiazepines : increase GABA, Diazepam, Lorazepam, Midazolam
how to reverse Benzodiazepines overdose
Flumazenil
Local Anesthetics 2 classes
AMIDE : have 2 iās in the name (Lidocine)
ESTER : only have 1 i in the name (cocaine)
ESTER vs AMIDE
ESTER Groups have higher risk of allergy causing compounds in them (hives, rash, itching, breathing difficulty)
how to administer local anesthetics
injections , IV
local anesthetics are usually given how and where
with Vasoconstrictor (unless cocaine) = give Epinephrine usually to vasoconstrict (DONT inject into end arteries like fingrs, toes, ear, nose....)****
local anesthetics adverse effects
high dose : nystagmus, muscular twitching, convulsions
lower CV output , hypotension (except cocaine)
ALLERGY (esp ESTERS)
USE of
- Lidocaine
- Cocaine
- Benzocaine
- Dibucaine
- Procaine
- antirrhythmic agent
- upper respiratory tract topical agent
- only topical agent
- skin cream due to toxic when injected
- inject to nerve ending directly (infiltration ansesthetic)
examples of organophosphates
echothiophate, parathion, malathion, sarin, soman
Organophosphates interact with what
AcheE (depleted) = replenish with PRALIDOXIME
reverse AchE inhibition
PRALIDOXIME
when to use a drug that stimulates AChR
- Glaucoma
2. NMJ (Myasthenia Gravis)
drugs used for Myasthenia Gravis 3
- Pyridostigmine
- Neostigmine
- Ambenonium
(AchE inhibitors)**
testing if someone has Myasthenia Gravis
Edrophonium Test, ice pack test, Ig testing
how to reverse NM blocking drug induced paralysis
- AchE (paralytic ilieus)
2. Neostigmine*
TX toxicity to AchE inhibitors intoxication and SX
SX : miosis, salvation, sweating, bronchial constriction, V, D
TX : Atropine
2 drugs used for Spasmolytics and side effects
- Carisoprodol (dizzy and drowsy)= anxiety
2. Cyclobenzaprine (sedation, confusion, hallucination, drowsy, dizzy, xerostomia) = antidepressant like TCA
5 other drugs for Spasmolytics besides cyclobenzapine and carisoprodol
- Baclofen
- Diazepam
- Tizanidine
- Dantrolene (non Central acting)
- Botulinum toxin (non central acting)
drugs for MS 4
- Glucocorticoids
- Glatiramer Acetate
- Interferons (INF-B1a, INF-B1b)
- Mitoxantrone
when to use NMBDs
- tracheal intubation
- surgery
- ventilation control
- convulsion tx
BEST NMBD
Succinylcholine BLOCKS DEPOLARIZATION*(Sochuronium, Vecuronium) = intubation and quick things
NMBD used for used as adjunct to general anesthesia for longer time
Pancuronium (Atracurium, Cisatracurium)
