Acid-Base, Electrolytes

Question 1

Diarrhea

Affects on electrolytes

Resulting Acid-Base deragement

Answer 1

Diarrhea

• Hyperkalemia
• Metabolic acidosis

Question 2

Vomitting

Affects on electrolytes

Resulting Acid-base deragement

Answer 2

Vomitting

• Hypokalemia
• Elevated bicarb
• Metabolic Alkalosis

Question 3

Etiologies of respiratory acidosis

Hypo or Hyper ventilation?

COPD or Asthma?

Answer 3

Respiratory Acidosis: Etiologies

Hypoventilation

COPD

Question 4

Respiratory Alkalosis: Etiologies

Hyper or Hypoventilation

Asthma or COPD

2 other systemic conditions

1 additional respiratory condition

Answer 4

Respiratory Alkalosis: Etiologies

Hyperventilation

Asthma

Liver disease Pregnancy

PE

Question 5

Hyponatremia

• Subtypes
• Cause and treatment for each

Answer 5

Hyponatremia

Subtypes

• Hypotonic hypovolemic: Diarrhea, Addison’s, Mass diuresis with loop or thiazide. Tx with fluid resusciation with normal saline.
• Hypotonic euvolemic: SIADH, polydipsia. Tx with ADH antagonist, treat underlying condition
• Hypotonic hypervolemic: Liver failure, Heart Failure, Nephrotic syndrome. Tx with fluid restriction
• Isotonic (or pseudohyponatremia): Hyperlipidemia, Hyperproteinemia. Also, rapid infusion osmotically active particles like glucose, mannitol. Tx with DDAVP.

Question 6

Hypernatremia

• Subtypes
• Cause and treatment for each

Answer 6

Hypernatremia

• Hypovolemic: More water loss than sodium loss
  
  • Renal loss
    
    • Thiazide Diuresis, Renal Failure
    • Non-ketotic hyperglycemia
  • Non-renal loss
    
    • Diarrhea
  • Treatment: calculate free water deficit and replace with isotonic fluid, treat underlying condition
• Euvolemic: Loss of water only
  
  • Diabetes insipidus. Can be central or psychogenic
  • Tx: DDAVP if central
• Hypervolemic: More water gain than sodium gain
  
  • Excess mineralocoticoids, Cushing Syndrome

Question 7

Hypokalemia

• Renal vs non-renal causes
• Symptoms
• Treatment

Answer 7

Hypokalemia

Renal

• Non-potassium sparing diuretics
• PCNs
• Magnesium depletion
• Alkalosis

Non-renal

• Diarrhea, Vomitting
• K+ pushed intracellularly (All adrenergics including Beta-2, insulin,

Symptoms generally absent unless <3.0

• Muscle cramps, lethargy, palpitations, paralysis, U waves on EKG (small wave after T wave)

Treatment:

• Replete with KCl, Magnesium

Question 8

Hyperkalemia

• Renal vs non-renal
• Symptoms
• Tx

Answer 8

Hyperkalemia

Renal

• Renal failure
• Meds: ACE-I, ARBs, Potassium sparing diuretics (sprinolactone), NSAIDS

Non-renal (releasing K+ from intracellular)

• Acidosis
• Crush injury
• Meds: Beta-blockers, CCB, succhinylcholine

Symptoms: N/V, weakness, Peaked T waves, Widened QRS, flattened P-waves,

Tx

• Kayexalate
• Insulin + dextrose
• Loop/thiazide diuretic, dialysis

Question 9

Calcium usually excreted in stool or urine?

Answer 9

Stool

Question 10

Hypocalcemia

• Causes
• Symptoms
• Treatment

Answer 10

Hypocalcemia

• Hypomagnasemia, Renal failure, Vit D deficiency, hypoparathyroidism, pancreatitis, blood transfusions, rhabdo, hypoalbuminemia
• Prolonged QT, tetany, seizures, Chvostek sign (flick facial nerve to elicit lip twitch
• Treatment: IV Ca, oral Ca, Calcitrol

Question 11

Hypercalcemia

• Causes
• Symptoms
• Treatment

Answer 11

Hypercalcemia

• Osteolytic metastasis, malignancy with PTHrP, Paget’s disease, granulomatous disease, multiple myeloma, hyperparathyroidism, thiazide diuretics
• Bones, Stones, Groans, Moans, Pyschic overtones, fatigue, weightloss, polydipsia, polyurea, death
• Volume resucitation, Furosemide, Parathyroidectomy, calcitonin, glucocorticoids