Week 11/12
Minutes
PBL 10: Can I drink beer?
Trigger 1:
What we
know?
Young man
Ambulance- E.D
w Mother
Semi-conscious
What we need to
know?
Hypotheses?
Is there a scale of
consciousness?
D- overdose? Illicit & other, poison, alcohol,
How long has he
been semiconscious for?
I-infection-meningitis-encephalitis, cerebral malaria,
viral, bacterial, protozoa agents.
M- malnutrition, disturbed electrolytes (Na+, K+,
Ca2+, Cl-), dehydration, hyperglycemia, Hormonal?hypothyroidism, Kidney failure->urea->toxic,
createnine.
T- trauma, head injury, brain tumour, Epileptic
seizure?
O- stroke (lack of oxygen)-genetic, diabetic. Anaemia.
Cardiovascular issue (reduced perfusion to the brain).
P- attempted suicide? Overdose drugs.
Trigger 2:
What we know?
Steven, 19y.o
Lives at home
Plays football 2x wk
V. social
Unwell for couple of days
Loosing weight recently
Always thirsty
No medication
What we need to know?
What are the types of
diabetes?
Hypotheses?
Diabates: Increased urine outut to excrete, increased thirst. But
Dehydration: Hyponatremic (primarily due to loss of ions, esp Sodium- would t),
hypernatremic (loss of water), isonatremic (combination of both- most common
form of dehydration).
Renal Failure- failure of excretory fn. Failure of acid secretion- conscious levels.
Chronic renal failure?
Thyroid disorders: endocrine, can cause hypo/hyperglycaemia.
Thyroid disorders- weight loss, crisis- heart failure.
Semicomatose + increased urine output-> diabetes mellitus, diabetes insipidus.
Trigger 3
Week 11/12
What we know?
What we need to know?
Level of consciousness- 11 What is the Glasgow coma
Glascow coma scale.
scale?
No sign of trauma
Breathing rapidly
Breath smells of acetone
BP 96/68
HR 128Bbp/min
Resp rate- 22 per minute
Blood glucose is 28mmol/L
(RR: 3.5-5.5 mmol/L).
A urine dipstick test
indicates glucose and
ketone bodies.
Minutes
Hypotheses
Glasgow coma scale:
Eye response- spontaneous (highest score of 4), verbal command (3), pain (2), no
response (1)
Motor response- Obey verbal command (6), pain response (5), withdraws from pain
stimulus (4), abnormal flexion (3), extensor response (2), No (1).
Verbal response- Oriented and converse (5), orientated but confused (4),
inappropriate words (3), incomprehensible (2), No (1).
Minimum=3, max 15.
Blood glucose levels:
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Blood glucose levels = normally 3.6 and 5.8 mM
Lack of insulin-> decreases efficiency of peripheral glucose utilization and augments
glucose production, raising plasma glucose to 30-120mg/L.
Increased blood glucose- more glucose to filter in renal tubules than can be
reabsorbed, excess in urine. Normally when above 18 (threshold).
Causes dehydration- glucose doesn’t diffuse easily thru pores of the cell membrane,
increased osmotic pressure extracellular causes water diffusing out of cells.
Thus polyuria- excretes water.
Inc glucose -> inc pyruvate -> inc avetly CoA -> Free fatty acids -> H+ -> ketone bodies -> co2
-> utilised in brain.
Ketone bodies:
Ketone breath- sweet, fruity odour. Excess glucose -> greater pyruvate-> greater acetyl coA> converted into ketone bodies (all occurring in the liver). Acetone (volatile compound
evaporates at room temp) broken down and smell is lost in breath and urine. Usually in the
breath when there is excess. Fruity odour. When dehydrated, will find ketone bodies in
urine. If increases more so, will excrete via breath.
Rapid breathing: increased ketone bodies (CCOO already donated their proton) causes
ketone acidosis. Excess ketones breaks down-> increased CO2 as a byproduct, produced all
in the liver-> results in increased breathing to excrete CO2.
Week 11/12
Wednesday:
QUESTIONS?
What mechanisms underly the development of acidosis?
How does the body deal with metabolic acidosis?
How is acid-base balance regulated?
Minutes