MICU QUESTIONS AND ANSWERS
3 most common causes of metabolic alkalosis
+ other causes! - Answer -vomiting
diuretics
mineralocorticol excess
(cushings, glucocorticoids, mineralocorticoids, hypoK, post chronic hypercapnea,
Bartter's, Gitelman, massive blood transfusion citrate)
3 causes of increased A-a gradient hypoxia - Answer -V/Q mismatch
Shunt (H2O, pus, blood)
Diffusion Dysfunction
2 causes of normal A-a gradient hypoxia - Answer -hypoventilation (central, muscular,
obesity)
decreased atmospheric pressure (high altitude)
Urine Chloride in saline-responsive met alk - Answer -<20
(stimulus for avid Na and Cl reabsorption to replenish extracellular volume)
All causes of metabolic alkalosis - Answer -incr aldosterone
loop diuretic or thiazide
ingestion of alkali stuff (antacids, milk, baking soda)
citrate (anticoagulant)
Loss of fluids (vom, GI suction)
Increased NaBicarb admin (overcompensating)
laxatives
CF
Causes of saline-resistant met alk - Answer -*hyperaldosterone ( hypertensive!)*
hypoK (<2)
Barrter's and Gitelman's
exog alkali
why is Na unreliable determinant of volume status in met alkalosis - Answer -increased
bicarb excretion leads to increased sodium excretion because bicarb "drags" Na out
with it
Clinical signs of hypovolemia (order of severity) - Answer -fast pulse, infrequent and
low volume urination, dry mucous membranes
poor capillary refill (usually <2 seconds), decreased skin turgor, weak pulse
orthostatic hypotension, orthostatic increase in pulse rate, cool extremities
what measurement can differentiate etiologies of met alk - Answer -urine chloride
,name causes of anion gap met acidosis - Answer -Methanol (formic acid)
Uremia
DKA / AKA
Paraldehyde / phenformin
Iron / INH
Lactic acidosis
Ethylene glycol (oxalic acid)
Salicylates
name causes of NON anion gap met acidosis - Answer -USEDCARS
Ureto-sigmoid (GI barcab loss), Ethanol, Endocrinopathies, *Diarrhea*, Carbonic
Anhydrase Inhibitors, hyperAlimentation (TPN), *RTA* (loss of bicarb from kidneys),
*Saline*
Winter's formula and when do you use it - Answer -PCO2 = 1.5 × [HCO3-]) + 8 ± 2
see if resp alkalosis is compensating for met acidosis
what ketones are detected in dipstick - Answer -acetoacetate and acetone, but not
beta-hydroxybutyrate (which usually in urine early)
Interpret delta-delta <1 - Answer -High AG & normal AG acidosis
Interpret delta-delta >2 - Answer -High AG acidosis and a concurrent metabolic
alkalosis
or a pre-existing compensated respiratory acidosis
Interpret delta-delta 1-2 - Answer -Pure Anion Gap Met Acidosis
Lactic acidosis: average value 1.6
DKA and AKA more likely to have a ratio closer to 1 due to urine ketone loss
common delta-delta ratio in DKA or AKA - Answer -1
common delta-delta ratio in lactic acidosis - Answer -1.6
Explain delta-delta equation and what it's used for - Answer -= (AG - 12) / (24 - [HCO3-
])
change in AG / change in bicarb
used in assessment of elevated anion gap metabolic acidosis to determine if a mixed
acid base disorder is present.
What is in Excedrin - Answer -acetaminophen and ASA
expected bicarb compensation and pH change in respiratory acidosis (acute and
chronic) - Answer -every 10 over 40
acute: bicarb 1, pH .08
chronic: bicarb 4, pH .03
, what additional value can effect anion gap and how - Answer -bicarb
highly negative and accounts for some of anion gap if it's very low
actual gap = calc gap + 2.5(4-albumin)
what is the equation for plasma osmolarity - Answer -Plasma osmolarity = 2(Na) +
glucose/18 + BUN/2.8
define osmolar gap - Answer -Osmolar Gap = Measured Posm - Calculated Posm
what is a normal osmolar gap - Answer -<10-15 mmol/L H20
what can increase the osmolar gap in anion-gap metabolic acidosis - Answer -ethanol,
ethylene glycol, methanol, acetone, isopropyl ethanol and propylene glycol
osmolar gap is used with which acid-base abnormality - Answer -anion-gap met
acidosis
what gap helps distinguish between non-AG metabolic acidosis - Answer -Urine Anion
Gap
= [Na+] + [K+] - [Cl-]
= unmeasured anions - unmeasured cations
what value is protein gap (gamma gap) elevated - Answer ->4
interpret a positive and negative urine anion gap - Answer -Non AG Metabolic Acidosis
negative UAG suggests GI loss of bicarbonate (eg diarrhea)
positive UAG suggests impaired renal acidification (ie renal tubular acidosis).
calculate A-a gradient - Answer -PAO2 - PaO2
PAO2 = FiO2(713) - (PaCO2/.8)
calculation for predicted A-a gradient - Answer -4+age/4
4 cardinal views - Answer -1. peristernal long axis
2. apical 4 chamber view
3. Parasternal Short Axis View (mitral valve)
4. subcostal 4 chamber
most common causes of myocarditis - Answer -coxsackie (developed)
chagas (s america)
lyme disease
rheumatic fever
cardiotoxic drugs (cocaine, chronic alcohol, CO doxiruben...)
systemic diseases (scleraderma, lupus, sarcoid)
3 most common causes of metabolic alkalosis
+ other causes! - Answer -vomiting
diuretics
mineralocorticol excess
(cushings, glucocorticoids, mineralocorticoids, hypoK, post chronic hypercapnea,
Bartter's, Gitelman, massive blood transfusion citrate)
3 causes of increased A-a gradient hypoxia - Answer -V/Q mismatch
Shunt (H2O, pus, blood)
Diffusion Dysfunction
2 causes of normal A-a gradient hypoxia - Answer -hypoventilation (central, muscular,
obesity)
decreased atmospheric pressure (high altitude)
Urine Chloride in saline-responsive met alk - Answer -<20
(stimulus for avid Na and Cl reabsorption to replenish extracellular volume)
All causes of metabolic alkalosis - Answer -incr aldosterone
loop diuretic or thiazide
ingestion of alkali stuff (antacids, milk, baking soda)
citrate (anticoagulant)
Loss of fluids (vom, GI suction)
Increased NaBicarb admin (overcompensating)
laxatives
CF
Causes of saline-resistant met alk - Answer -*hyperaldosterone ( hypertensive!)*
hypoK (<2)
Barrter's and Gitelman's
exog alkali
why is Na unreliable determinant of volume status in met alkalosis - Answer -increased
bicarb excretion leads to increased sodium excretion because bicarb "drags" Na out
with it
Clinical signs of hypovolemia (order of severity) - Answer -fast pulse, infrequent and
low volume urination, dry mucous membranes
poor capillary refill (usually <2 seconds), decreased skin turgor, weak pulse
orthostatic hypotension, orthostatic increase in pulse rate, cool extremities
what measurement can differentiate etiologies of met alk - Answer -urine chloride
,name causes of anion gap met acidosis - Answer -Methanol (formic acid)
Uremia
DKA / AKA
Paraldehyde / phenformin
Iron / INH
Lactic acidosis
Ethylene glycol (oxalic acid)
Salicylates
name causes of NON anion gap met acidosis - Answer -USEDCARS
Ureto-sigmoid (GI barcab loss), Ethanol, Endocrinopathies, *Diarrhea*, Carbonic
Anhydrase Inhibitors, hyperAlimentation (TPN), *RTA* (loss of bicarb from kidneys),
*Saline*
Winter's formula and when do you use it - Answer -PCO2 = 1.5 × [HCO3-]) + 8 ± 2
see if resp alkalosis is compensating for met acidosis
what ketones are detected in dipstick - Answer -acetoacetate and acetone, but not
beta-hydroxybutyrate (which usually in urine early)
Interpret delta-delta <1 - Answer -High AG & normal AG acidosis
Interpret delta-delta >2 - Answer -High AG acidosis and a concurrent metabolic
alkalosis
or a pre-existing compensated respiratory acidosis
Interpret delta-delta 1-2 - Answer -Pure Anion Gap Met Acidosis
Lactic acidosis: average value 1.6
DKA and AKA more likely to have a ratio closer to 1 due to urine ketone loss
common delta-delta ratio in DKA or AKA - Answer -1
common delta-delta ratio in lactic acidosis - Answer -1.6
Explain delta-delta equation and what it's used for - Answer -= (AG - 12) / (24 - [HCO3-
])
change in AG / change in bicarb
used in assessment of elevated anion gap metabolic acidosis to determine if a mixed
acid base disorder is present.
What is in Excedrin - Answer -acetaminophen and ASA
expected bicarb compensation and pH change in respiratory acidosis (acute and
chronic) - Answer -every 10 over 40
acute: bicarb 1, pH .08
chronic: bicarb 4, pH .03
, what additional value can effect anion gap and how - Answer -bicarb
highly negative and accounts for some of anion gap if it's very low
actual gap = calc gap + 2.5(4-albumin)
what is the equation for plasma osmolarity - Answer -Plasma osmolarity = 2(Na) +
glucose/18 + BUN/2.8
define osmolar gap - Answer -Osmolar Gap = Measured Posm - Calculated Posm
what is a normal osmolar gap - Answer -<10-15 mmol/L H20
what can increase the osmolar gap in anion-gap metabolic acidosis - Answer -ethanol,
ethylene glycol, methanol, acetone, isopropyl ethanol and propylene glycol
osmolar gap is used with which acid-base abnormality - Answer -anion-gap met
acidosis
what gap helps distinguish between non-AG metabolic acidosis - Answer -Urine Anion
Gap
= [Na+] + [K+] - [Cl-]
= unmeasured anions - unmeasured cations
what value is protein gap (gamma gap) elevated - Answer ->4
interpret a positive and negative urine anion gap - Answer -Non AG Metabolic Acidosis
negative UAG suggests GI loss of bicarbonate (eg diarrhea)
positive UAG suggests impaired renal acidification (ie renal tubular acidosis).
calculate A-a gradient - Answer -PAO2 - PaO2
PAO2 = FiO2(713) - (PaCO2/.8)
calculation for predicted A-a gradient - Answer -4+age/4
4 cardinal views - Answer -1. peristernal long axis
2. apical 4 chamber view
3. Parasternal Short Axis View (mitral valve)
4. subcostal 4 chamber
most common causes of myocarditis - Answer -coxsackie (developed)
chagas (s america)
lyme disease
rheumatic fever
cardiotoxic drugs (cocaine, chronic alcohol, CO doxiruben...)
systemic diseases (scleraderma, lupus, sarcoid)
