Acid Base Flashcards
What is the pH in resp acid?
Decreased
What is the PaCO2 in resp acidosis?
primary increase in partial pressure of CO2 (pCO2)
What (general) causes resp acidosis?
Alveolar hypoventilation
What is a consequence of resp acidosis?
CO2 retention in lungs
What are some disorders that lead to resp acidosis?
- Disorders that reduce pulmonary function and CO2 clearance
-Primary pulmonary disease:
COPD
-Neuromuscular disease:
Myasthenia gravis
-Primary CNS dysfunction:
Brainstem injury
-Drug induced hypoventilation:
Opioids
Methadone
TCA’s
What are the clinical sxs of resp acidosis?
- Early
Headache
Drowsiness - Late (uncorrected)
Stupor
Coma
What are the early lab findings of resp acidosis?
- Acute CO2 retention:
increased pCO2
Minimal change in plasma HCO3
Serum electrolytes close to normal
What are the lab findings after 2-3 days in resp acidosis?
↑ H+ secretion
↑ HCO3 production in distal convoluted tubule
Plasma HCO3 steadily increases
What is the tx for resp acidosis?
Underlying disorder must be identified and corrected
Blood pCO2 > 60 mm Hg may indicate need for assisted ventilation if CNS or pulmonary muscle depression is severe
What (generally) causes resp alkalosis?
excessive elimination of CO2 from lungs
What is the pH level in resp alkalosis?
Increased
What are the Co2 levels in resp alkalosis?
Decreased
What are some disorders that cause resp alkalosis?
- Disorders asst with inappropriately increased resp. rate and increasedCO2 clearance
-Anxiety/Hyperventilation
(Most common cause)
-Salicylate intoxication
-Hypoxia
-Primary CNS dysfunction
-Gram neg septicemia
-Pregnancy
What are the clinical features of resp. alkalosis?
Hyperventilation Paresthesias Lightheadeness Giddiness Acute alkalemia may produce tetany like syndrome which is indistinguishable from hypocalcemia
What are the lab findings in acute alkalosis?
Increased blood pH
Decreased pCO2
What are the lab findings after a few hours of resp alkalosis?
- H+ secretion in distal convoluted tubules ↓
- Decreased in plasma HCO3
- Serum chloride (Cl) level increases
What are the treatments for resp alkalosis?
Correct underlying disorder
Breath in paper bag
Assisted ventilation may be required
What is the pH level in metabolic acidosis?
Decreased
What is the PaCo2 level in metabolic acidosis?
Normal
What is the HCO3 level in metabolic acidosis?
Decreased.
What causes metabolic acidosis through an increased anion gap?
1. Increased anion gap from accumulation of acid: Lactic acidosis DKA Starvation ketosis Ethylene glycol intoxication Methanol intoxication Salicylate intoxication
What causes metabolic acidosis through a loss of HCO3?
Normal anion gap caused by loss of HCO3:
Diarrhea
Pancreatic drainage
Biliary drainage
What are the clinical sxs of metabolic acidosis?
- Hyperventilation is the earliest and most recognized sign
Results from stimulation of respiratory drive to blow off CO2 - Ventricular arrhythmias may occur
- Neurologic complications range from lethargy to coma
What are the lab results in metabolic acidosis?
Blood pH < 7.35
Decreased plasma HCO3
Decreased pCO2
