crit care Flashcards
Causes of obstructive lung disease
Asthma
bronchiectasis COPD
bronchiolitis obliterans
Causes of restrictive lung disease
pulmonary fibrosis
kyphsclerosis
ARDS
neuromuscular causes
Spirometry findings in obstructive LD:
FEV1
FVC
FEV1/FVC
Reduction in FEV1>FVC
hence FEV1:FVC reduced <70%
Spirometry findings in RESTRICTIVE LD:
FEV1
FVC
FEV1/FVC
Reduction in FEV1<FVC
hence FEV1:FVC normal/ raised >70%
Anaesthetic agent that has both anaesthetic and analgesic properties but causes dissociative anaesthetic effect (hallucinations/ nightmares)
Ketamine
Anaesthetic agent causing the most and least myocardial depression
most= sodium thiopentone (squeezy)
least= Etomidate
Anaesthetic agent causing adrenal suppression
Etomidate
Anaesthetic agent that has anti-emetic properties
Propofol
Anaesthetic agent which is used in RSI
Sodium thiopentone (speedy)
Why are sodium thiopentone and etomidate unsuitable for maintaining sedation
ST= metabolites build up quickly
E= causes adrenal suppression even with brief use
Side effect of using Etomidate
PONV
Causes of neuropathic pain
damage to nervous system:
diabetic neuropathy
trigeminal neuralgia
post-herpetic neuralgia
prolapsed IV disc
First and second line mx of neuropathic pain
1= amitriptyline/ pregabalin
2= add amitriptyline/ pregabalin
3= refer to pain specialist, neurectomy
Mx of diabetic neuropathy
Duloxetine
Mx of trigeminal neuralgia
Carbamazepine
How much calories should be given to a non-severely ill patient with BMI<25
25-35kcal/kg/day
What is the daily requirement of protein
0.8-1.5g/kg/day
How much calories should be given to a severely ill patient
50% of 25-35kcal/kg/day in the first 24-48hrs
How many calories should be given to a patient at risk of refeeding syndrome
10kcal/kg/day
What other supplements should be given to those at risk of refeeding syndrome
Pre-feeding and during feeding:
Thiamine (200-300mg)
Vitamin B complex strong 1tab TDS
Potassium (2-4)
Magnesium (0.2-0.4)
Phosphate (0.3-0.6)
causes of refeeding syndrome
reduced intake:
eating disorders
chemo
vomiting
post-op
fasting
prolonged NBM
reduced absorption
chemo
IBD
short bowel syndrome
pancreatitis
cystic fibrosis
describe the pathophysiology of refeeding syndrome
prolonged reduced nutrients= reduced levels of body phosphate, K, Mg (serum levels normal)
Start eating= increase in glucose + insulin= rapid shift of phosphate, Mg, K into cells for use= decrease in serum phos, Mg, K levels= seizures, arrthymias
What are the types of muscles relaxants
(all end in -ium)
Suxamethonium
Atracurium
Vecuronium
Pancuronium
Which muscle relaxant causes generalised muscle contractions and why
Suxamethonium
Because it is a depolarizing Neuromuscular blocker hence prior to paralysis the depolarization of the NM membrane causes muscle fasciculations
How is sux broken down in the body
By cholinesterase and acetylcholinesterase
What does sux act on to produce muscle paralysis
Acetylcholine receptors at the NM junction
What are the adverse effects of sux
-malignant hyperthermia
-increased intraocular pressure
-prolonged paralysis (in those with reduced pseudocholinesterase levels )
-hyperkalaemia (not good in burns/ necrosis pt= hyperk= cardiac arrest)
Which muscles relaxant is the quickest acting and shortest duration
suxamethonium
How quickly do atracurium, vecuronium and pancuronium act
atra + vecronium= 30-40mins
pancuronium= 2-3mins
Which muscle relaxant is broken down in the liver/ kidneys
pancuronium + vecuronium
How is atracurium broken down
by hydrolysis in tissues and causes histamine release
Adverse effects of atracurium
Histamine release= flushing, tachycardia, hypotension