Basic Science Flashcards
Give 4-8 causes of high anion gap metabolic acidosis.
4 (DRLT) = Diabetic ketoacidosis, Renal impairment, Lactic
acidosis, Toxins
8 (MUDPILES) = Methanol, Uraemia, DKA, Phenaldehyde, Infection, Lactate, Ethanol, Salicylates
List 4 acids in the body
Volatile (1) = CO2
Non-volatile (3) = H2PO4-, lactate, H2C03
Given HCO3-, how is PCO2 estimated? What is the clinical utility of this?
Estimation of PCO2, if outside of estimate then a mixed acid/base disorder:
PCO2 = 1.5(HCO3-) + 8
Describe the regulation of acid-base-balance in the body in simple terms.
CNS – regulates respiration and hence CO2 levels
Kidney:
- Reabsorption of HCO3- levels (PT>DT)
- Titratable acid regulation in DT (HPO4- and NH4+)
Give 2-6 causes of non-AG metabolic acidosis.
Causes of non-anion gap metabolic acidosis:
SHORT (2 - DR): diarrhoea and RTA
LONG (6 – HARDUP): hyperalimentation (starting TPN), acetozolamide use, RTA, diarrhoea, uretosigmoid fistula (colon wastes HCO3-), pancreatic fistula (HCO3- secretion by pancreas)
What is the Henderson-Hasselbalch equation?
pH = 6.1 + log (HCO3- / 0.03 x pCO2)
Describe oxidation and reduction in terms of electron transfer.
OIL RIG:
Oxidation involves loss of electrons i.e. oxidant is acceptor of electrons
Reduction involves gain of electrons i.e. reductant is a donor of electrons
List the conditions in MEN I, IIA and IIB.
MEN (multiple endocrine neoplasia) syndromes:
MEN I (3Ps): pituitary, pancreas, parathyroid*
MEN IIA (2P+1M): parathyroid*, medullary thyroid+, phaeochromocytoma~
MEN IIB (1P+2M): phaeochromocytoma~, medullary thyroid+, marfanoid / mucosal neuroma
- / + / ~ are all repeated!
What hormonal imbalance causes gynaecomastia? Give some causes.
Gynaecomastia is due to an imbalance of oestrogen and testosterone:
Causes: Hyperthyroidism, Seminoma
Which of the following are causes of gynaecomastia?
Hyperprolactinaemia Hypothyroidism Hypopituitarism Seminoma Congenital Adrenal Hyperplasia
NOT causes: Hypothyroidism, Congenital Adrenal Hyperplasia
Rarely: Hyperprolactinaemia, hypopituitarism
Most likely = Seminoma
How is anion gap calculated?
What is normal range?
AG = Na + K - HCO3 - Cl
Normal = 8 - 16
What is mnemonic for all causes of metabolic acidosis (normal and high anion gap)
HARD-UP MUD-PILES
Normal AG (HARD-UP) hyperalimentations (i.e. TPN), acetozolamide (type 2 RTA), RTA, diarrhoea, uretosigmoidal fistula (HCO3- loss in colon), pancreatic fistula (HCO3 loss from pancreas)
Simple normal AG (DR): diarrhoea and RTA
High AG (MUD-PILES): methanol, uraemia, DKA, phenylaldehyde, infection, lactate, ethanol, salicylates
Simple high AG (DR-LT): DKA, renal impairment, lactate, toxins
