Blood gases Flashcards
Respiratory Alkalosis: Chronic causes
Hypoxia Interstitial lung disease Pregnancy Severe anemia CHF Hepatic insufficiency
Respiratory Alkalosis: Treatment
Correct underlying cause
Decrease ventilatory rate as long as O2 not adversely affected
Increase ventilatory dead space
Metabolic Alkalosis: Causes
Increased bicarbonate
Chloride responsive
-Bicarb increases because Cl is decreasing
-Gastric fluid loss because of vomiting/suctioning (a)
-Diuretics (thiazides, loops) (c)
Chloride unresponsive
- Bicarb increasing with no relation to Cl - Hyperaldosteronism - Severe hypokalemia - Iatrogenic alkali administration (acetate in TPN)
Respiratory Alkalosis: Acute Causes
Hypoxia Nervousness Anxiety Pain PE Hyperthyroidism CNS injury Fever Asthma
Metabolic Alkalosis: Treatment
Correct underlying cause
Correct hyopkalemia
Volume replacement with NS or Cl replacement
Acetazolamide 250-500 mg po/IV q8h for 3-4 doses
H2 antagonists or PPI (prevent gastric secretion of HCl)
Emergency cases (IV HCl or arginine HCl, ammonium Cl)
Respiratory Acidosis: Acute Causes
Increased CO2 because increased respiratory rate
Retaining bicarb
Pulmonary Embolism
Over sedation
Neuromuscular blockade
Hypothyroidism
Respiratory Acidosis: Chronic Causes
Increased CO2 because increased respiratory rate
Retaining bicarb
COPD Interstitial lung disease Hypothyroidism Neuromuscular disorder Hypovention
Respiratory Acidosis: Treatment
Correct underlying cause
Oxygen replacement
Increase ventilatory rate as long as Oxygen not adversely affected
Replace bicarb only in cases of severe/refractory (will worsen hypoventilation)
Metabolic Acidosis: Causes
Anion gap (
Metabolic Acidosis: Treatment Chronic
Treat underlying causes Acetate in TPN NaHCO3 tabs Shohl's solution In divided doses, total dose = 24-48 mEq
Metabolic Acidosis: Treatment Acute
Treat underlying causes
Acetate in TPN
REplace bicarb if pH
