GA and LA Flashcards
1
Q
Path of Inhaled GA
- pK factors
- MOA, name 1
- Effects, AE
A
Lungs then blood then brain
- blood solubility - lower solubility faster saturation faster deliver
- Fat solubility - more lipophilic faster delivery to brain
- pulmonary ventilation; pulmonary blood flow
- AV conc gradient
Nitric Oxide;
- GABA, Cl flux
- Depresses Respir, CVS, MAP
- Brain Blood Flow increases - not used in RICP
- Decreased perfusion of Liver, Renal
- can have liver, renal toxicity
2
Q
IV GA
- is faster than inhaled cos skip lungs
- Name and describe 2 classes
note Propofol and Ketamine are IV GAs too
A
Barbituates
- Thiopental
- ACTIVATES GABA
- wo increasing cerebral BF;
- high lipo solubility, fast out of blood and brain to muscles fats
- i think fast onset, but slow recovery
BZD - midazolam, diazepam, lorazepam; alprazolam
- POTENTIATES GABA
- not enough plateau on its own for surgery
- hence adjunct / pre surgery use
3
Q
Whats the pH of LA and whats the point
MOA
A
LA are weak bases
- uncharged form for lipid penetration, charged form to stay in cells
- hence inject tgt w sodium bicarbonate;
Intracellular block of sodium channels
- in nerves, CNS, heart
- reduces depolarization
4
Q
Gimme the 2 pain fibers
A
A delta
- myelinated
C fibers
- demyelinated
- shorter diameter than A
5
Q
LA Toxicity
note Procaine is an ester type local anaesthetic, lidocaine is an amide type local anaesthetic
- Epinephrine vasoconstrictor to reduce systemic absorption – improve duration of drug
A
Systemic effects
- CNS - drowsiness; tongue numbness; nystagmus, muscle twitching; seizures, comas
- CVS - depression, arrhythmia
- allergies
6
Q
Opioid MOA
AE
Note from mild to moderate to severe pain
- opioids are only given for MODERATE and above
A
Bind to GPCR - MU receptor is GCPR!!!
- close VG Calcium channels
- block NT release from pre-S neuron
CNS: analgesia - euphoria, sedation - respi depression, COUGH DEPRESSANT CVS Bradycardia GI Constipation!
