Drugs
What is an acid-base disturbance that can be caused by Metformin?
Lactic acidosis--use with caution for patients with renal insufficiency
What is the main site of injury in ARDS (acute respiratory distress syndrome)?
Alveolar-capillary membrane:
Insult --> increase alveolar-capillary membrane permeability --> fluid moves into alveoli --> barrier against normal gas exchange
What is insulin's effect on potassium?
Insulin shifts potassium into cells
What are TIRs and TORs?
Time in Range
Time out of Range
Better than HbA1C for determining glucose control in Diabetes Management
What's a Dieulafoy lesion?
Large, tortuous arteriole most commonly in the submucosal layer of the gastric wall that erodes and bleeds
Can present in any part of the GIT
Sulfonylureas (glipizide) can cause what major side effect?
Hypoglycemia (increase risk in renal insufficiency).
Also, weight gain and disulfiram-like reactions (1st gen)
What is the leading cause of transfusion related mortality?
TRALI
You have a patient in the ICU with DKA and muscle weakness. What lab should you check and what would you expect (high/low)? Why?
Low PO4! (B&B says high yield)
DKA --> metabolic acidosis --> shift PO4 out to extracellular fluid
Osmotic diuresis --> phosphaturia
Lack of available inorganic phosphate for making ATP/energy --> breakdown of stored ATP --> Can't support muscles (esp. respiratory muscle contraction--needs ATP!) --> Weakness, myalgia, arthralgia, rhabdomyolysis, respiratory failure
Why don't Type 2 Diabetes tend to get DKA?
Some of their insulin is still working --> enough to prevent ketogenesis (--> DKA). Usually no acidosis.
What's the difference between an ulcer and erosion?
Ulcer: area of damage to GI wall that extends beyond lamina propria (can perforate).
Erosion: inflammation of mucous membrane
Ranitidine is an H2-receptor blocker --> decreased H+ secretion by parietal cells. It causes decreased renal excretion of what compound?
What is the 2-hit mechanism for TRALI?
1. Recipient risk factors --> PMNs are sequestered and primed in pulmonary vasculature
2. PMNs activated by product in transfused blood (antileukocyte antibodies) --> release inflammatory mediators --> increase capillary permeability --> pulmonary edema
What is the mechanism for hyponatremia in diabetes
Osmotic diuresis-induced hypovolemia: Hyperglycemia --> hyperosmolar urine --> osmotic diuresis (pushes out water and sodium into urine)
What is hyperosmolar hyperglycemic state, and which diabetes (type 1, type 2) is it associated with?
Type 2 Diabetes Mellitus
Profound hyperglycemia --> high serum osmolality --> excessive osmotic diuresis --> dehydration --> HHS
Can lead to coma & death
**No ketones
What is the pathogenesis of Dieulafoy's lesion?
Arterial tree branches normally become more narrow as they get more distal. BUT in Dieulafoy lesions maintain their large caliber (don't undergo normal branching) --> don't know why.
Fluoroquinolones (levofloxacin) should be avoided in elderly patients and patients taking prednisone because of what adverse effect?
Tendonitis or tendon rupture
What is the diagnostic criteria for ARDS?
ARDS:
A: Abnormal CXR (b/l lung opacities--> White out!)
R: Respiratory failure within 1 week of insult
D: Decreased PaO2/FiO2 (ratio < 300, hypoxemia d/t increased intrapulmonary shunting and diffusion abnormality)
S: Sxs of respiratory failure NOT d/t HF/fluid overload
What is the fractional excretion of sodium?
Urine Chemistries:
Na = 8mEq/L
Cre = 55.7 mg/dL
Serum Chemistries:
Na = 134 mEq/L
Cre = 1.5 mg/dL
FENa = [Urine (Na) x Plasma (Cr)] / [Urine (Cr) x Plasma (Na)] x 100
= 0.16%
FENa < 2% --> Pre-renal (you're absorbing Na like you're supposed to--kidneys work!)
What is a common skin finding in diabetes and what is the associated cancer?
Acanthosis nigracans seen with insulin resistance.
Rarely associated with malignancy: Gastric adenocarcinoma most common
How do you treat a Dieulafoy Lesion?
1. Inject with epinephrine --> induce vasospasm to establish homeostasis
2. Thermal/electrical ablation--stop the bleed!
3. Band ligation: tie it off
15% recurrence rate
Loop diuretics (Furosemide) inhibit Na/K/2Cl cotransporter on the TAL. What electrolyte abnormalities can it cause (3)?
Hypokalemia
Hypomagnesemia
Hypocalcemia
What can you give the patient to distinguish between TACO and TRALI?
Diuretics: flush out excess fluid (TACO)
TACO: non-immune mediated complication
Fluid overload d/t transfusion
1 unit of insulin drops blood glucose by about how much?
~ 50 mg/dL
Hyperglycemia --> nonenzymatic glycation of tissue proteins --> diabetic glomerulonephropathy. List 3 light microscopy findings.
Mesangial expansion (NEG of tissue proteins) --> increase hyaline arteriolosclerosis --> Kimmelstiel-Wilson Lesions (eosinophilic nodular glomerulosclerosis)
GBM thickening & increased permeability --> hyperfiltration --> glomerular hypertrophy & scarring (glomerulosclerosis)
How do you spell Dieulafoy?
JK