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acid base pathophys
If a person were to hyperventilate, there would be a/an _________ in CO₂excretion.
If a person were to hypoventilate, there would be a/an _________ in CO₂excretion.
Acidosis based on a pH _________.
Alkalosis based on a pH __________.
pH < 7.35 with an increased pCO₂
pH < 7.35 with a decrease in bicarb
pH < 7.35 with a low bicarb and low pCO₂
Compensated metabolic acidosis
pH < 7.35 with a high pCO₂and a high bicarb
Compensated respiratory acidosis
pH is >7.45 and a low pCO₂
pH is >7.45 and a high bicarb
pH is >7.45 and the bicarb and pCO₂are high
Compensated metabolic alkalosis
pH is >7.45 and the pCO₂and bicarb are both low
Compensated respiratory alkalosis
Mild acidosis pH range
Moderate acidosis pH range
Severe acidosis pH range
Mild alkalosis range
Moderate alkalosis range
Severe alkalosis range
[Na+] - [Cl- + [HCO₃]
7 possible etiologies of metabolic acidosis with elevated anion gap
Methanol ingestion, Uremia, Diabetic ketoacidosis, Propylene glycol ingestion, Ischemia with lactic acidosis, Ethylene glycol ingestion, Salicylate intoxication (MUDPIES)
Normal anion gap
6 possible etiologies of metabolic acidosis with a normal anion gap
Hyperalimentation, Acetazolamide, Renal tubular acidosis, Diarrhea, Ureterosigmoidostomy, and Pancreatic fistula (HARDUP)
Metabolic acidosis compensation rule
pCO₂decreases by 1-1.5 mmHg below normal (40 mmHg) for every 1 mEq/L decrease in HCO₃below normal (24 mEq/L)
Two "types" of metabolic alkalosis
cholride resistant and chloride sensitive
In order for metabolic alkalosis to be chloride resistant, it must have a urine chloride of _________.
In order for metabolic alkalosis to be chloride sensitive, it must have a urine chloride of ___________.
Etiologies of chloride resistant metabolic alkalosis
Excessive mineralocorticoid activity, Hyperaldosteronism, Cushing's syndrome, Bartter's syndrome, Severe potassium depletion
Etiologies of choride sensitive metabolic alkalosis
GI disorders, diuretic therapy, cystic fibrosis, correction of chronic hypercapnia
Metabolic alkalosis compensation rule
pCO₂increases by 0.6-0.7 mmHg above normal (40 mmHg) for every 1 mEq/L increase in HCO₃above normal (24 mEq/L)
Etiologies of Acute respiratory acidosis
Impaired perfusion, impaired ventilation, CNS depression, spinal cord injury
Etiologies of Chronic respiratory acidosis
impaired ventilation, muscular problems, strokes, tumors, MS
Clinical manifestations of respiratory acidosis
Headache, papilledema, abnormal reflexes
Acutely compensated respiratory acidosis rule
HCO₃increases by 1 mEq/L above normal (24 mEq/L) for every 10 mmHg increase in pCO₂above normal (40 mmHg)
Chronically compensated respiratory acidosis rule
HCO₃increases by 4 mEq/L above normal (24 mEq/L) for every 10 mmHg increase in pCO₂above normal (40 mmHg)
Etiologies of respiratory alkalosis
hypotension, stroke, head trauma, pulmonary embolism, congestive heart failure, pneumonia, physical increase in ventilation, medications (salicylates, nicotine, catecholamines)
Clinical manifestations of respiratory alkalosis
lightheadedness, confusion, nausea, vomitting, arrythmias, slight increase in potassium
Acutely compensated respiratory alkalosis rule
HCO₃decreases by 2-3 mEq/L below normal (24 mEq/L) for every 10 mmHg decrease in pCO₂below normal (40 mmHg)
Chronically compensated respiratory alkalosis rule
HCO₃decreases by 5 mEq/L below normal (24 mEq/L) for every 10 mmHg decrease in pCO₂below normal (40 mmHg)
What is the main determinant of systemic pH?
bicarbonate/carbonic acid buffer system
pH is >7.45 and the bicarb is low and the pCO₂is high
mixed acid base respiratory and metabolic alkalosis