Anaesthetic

Question 1

list anaesthetic adjunct and use

Answer 1

1. BZD (midazolam): sedation, amnesia, anxiolytic prior to GA
   : sedation during procedure not req GA (as it can cause sedation ~30min by itself)
2. NSAIDS, paracetamol: minor surgery for analgesia to decrease dose of GA
   Opioid (fentanyl, morphine, alfentanil, remifentanil, sufentanil): peri-operative
   Choice of opioid: based on DOA (how long u want the opioid to work)
3. a2: DexMeDeToMiDine (DMDTMD): not reliable sedation prior to/during surgery for non-intubated pts (as it cause little resp depression) + analgesic
4. NM blocking (succinylcholine, vecuronium): relax muscle in jaws, neck, airway to facilitate intubation

Question 2

Caution for GA or adjunct for hepatic pt

Answer 2

adjunct: ketamine, midazolam, opioid/paracetamol/NSAID

Question 3

propofol use and SE and special precaution to who?

Answer 3

use: day surgery, induction (rapid onset), maintenance (multiple injection/ infusion)
SE: post-operative V (similar to N2O)
: during induction, significant hypotension
–> caution in elderly pt / compromised CV function/ hypovolemic pt

Question 4

ketamine use and SE

Answer 4

only IV GA with analgesic property (thiopental and propofol dont have)
dissociative anaesthesia
sedation, amnesia
longer recovery than propofol and thiopental
SE: during recovery, have unpleasant psychological rxt like hallucination/delirium/disturbing dreams
–> use midazolam (adjunct)/ diazepam premedication to decrease risk

Question 5

inhalation GA that gives toxic metabolite

Answer 5

halothane metabolite: hepatitis
sevoflurane: degrade to nephrotoxic compound when exposed to co2 absorbent in anaesthetic machine
enflurane, isoflurane: also nephrotoxic inorganic f-
(except desflurane)

Question 6

more soluble is the inhalation GA in blood –>

Faster onset –>

Answer 6

slower onset (dont want to partition into the brain)
--> N2O is less soluble so faster onset

means faster elimination by lungs

Question 7

onset and recovery speed for the inhalation GA

Answer 7

fastest: n2O –> sevoflurane > iso/halothane/enflurane

Question 8

halothane SE

isoflurane SE

Answer 8

resp depression (dose-dependent),
hypotension, bradycardia, , dysrhythmia,
halothane-induced hepatitis

Resp depression, lesser hypotension/arrhythmia than halothane, nephrotoxic metabolite

Question 9

DMDTMD

SE

Answer 9

dexmedetomidine

anti cholinergic, N, slight hypotension & bradycardia

Question 10

ester LA

amide LA

Answer 10

ester: Procaine (short DOA)
           tetracaine benzocaine (long DOA)

Amide: Lidocaine/xylocaine/lignocaine (med DOA)
Prilocaine (med DOA)
Bupivacaine (long DOA)

Question 11

adv and disadv of ester and amide LA

Answer 11

Ester: less affected by liver function
Amide: less allergy (ester hydrolysed by esterase to PABA derivative)

Question 12

SE of LA

Answer 12

CV : cardiac contraction (bupivacaine is more cardiotoxicity than other LA)
hypotension
arteriolar dilation
CV COLLAPSE

sleepy/ restless 
nystamus
shivering, contraction
stopping of vital function
DEATH 

prilocaine: methaemoglobin –> use IV methylene blue/ascorbic acid