ABG, Acid, Base
Most common underlying disorder in respiratory acidosis
What is alveolar hypoventilation leading to hypercarbia.
What is the sodium concentration in Normal Saline 0.9% in mEq/L?
154 mEq/L
When do patients become symptomatic with hyponatremia?
What is under 125 mEq/L
EKG changes with hyperkalemia?
What is 6-7 mEq/L narrow and peaked T waves, shortened QT interval. Progresses to a widened QRS and prolonged PR, flattened P waves, possible second or third degree AV block. Eventually goes to sinusoidal wave.
Clincial manifestations hypercalcemia?
What are altered MS, lethargy, depression, N/V, bone pain, polydipsia, renal calculi. See around Ca 14mg/100mL
Stone, Bones, Abdominal moans, psychiatric overtones
pH and PCO2 changes with acute respiratory acidosis
What is pH decreases 0.05-0.08 for each 10 mm Hg increase in PCO2
What is the ratio for crystalloid versus colloid when replacing blood loss?
crystalloid 3:1 colloid 1:1
What are the EKG changes with hyponatremia?
What is Na below 115 mEq/L = widening QRS and ST elevation
EKG effects of hypokalemia?
What are flattening T waves, U waves, increased amplitude p wave, PR prolongation, ST seg depression.
Treatment for hypermagnesemia
What is 1 G calcium gluconate or 500 mg Ca chloride
Apnea affects PaCO2 in what way?
What is PaCO2 increases by 6 mm Hg in the first minute of apnea, then increases by 3 mm Hg for each minute thereafter
What does lactated ringers contain that normal saline does not?
Calcium, lactate, potassium
How fast should hyponatremia be corrected?
What is no faster than 0.5-1 mEq/L hour
How magnesium depletion affects potassium?
What is potassium wasting and hypocalcemia
Think decrease in Mg, K, and Ca together.
Effect of hypermagnesemia on muscle relaxants (both dep and non dep)
What is potentiates both (+ LAs)
What is acute respiratory response to metabolic alkalosis?
What is reflex alveolar hypoventilation = PaCO2 increases 0.5-0.6 mm Hg per 1 mEq increase in bicarb.
Adverse effects of hyperchloremia after normal saline infusion?
Acidosis, coagulopathy, renal vasoconstriction, increased PONV
What is pseudohyponatremia?
What is isotonic hyponatremia, lab artifact secondary to severe hyperproteinemia or hyperlipidemia. Na concentration normal.
Treatment for acute hyperkalemia?
What is 1) protect heart = Calcium chloride 500 mg or 1 G calcium gluconate 2) drive K intracellular = 5-10 regular insulin, 25-50 G dextrose (down K 10-20 min last 4-6 hrs), B agonists, hyperventilate, Diuretics furosemide, resin exchange Kayexalate, dialysis
Medical therapy hypercalcemia
What is NS infusion with K, furosemide diuresis, pamidronate, calcitonin, dialysis.
What happens to the PaO2 and PaCO2 in ABG with air bubble trapped?
What is move toward air equilibration. PaO2 moves to 150 mm Hg, PaCO2 tends to decrease toward 0.
What causes metabolic acidosis seen with large volume normal saline?
Dilutional reduction of bicarbonate or reduction of strong ion difference
How is plasma sodium interpreted with hyperglycemia?
What is high glucose draws water out of cells and dilutes sodium in plasma. Every 100mg/dL glucose above 200mg/dL serum sodium decreased by 1.6mEq/L
How does acidosis and alkalosis affect potassium levels?
What is Acidosis = plasma K increases 0.6 mEq/L per 0.1 change in arterial pH.
Alkalosis = K concentration decreases
What levels of Mg cause loss of DTR's, Resp arrest and coma, asystole
What are DTRs = 10-12 mg/dL, Resp arrest/coma 15-20 mg/dL, asystole 20-25 mg/dL