Acid-Base Flashcards
Substance that releases H+ ion when dissolved in water
acid
Substance that binds free H+ ions in solution
base
Most common base in body
HCO3- (bicarbonate)
Most common acid in body
H2CO3- (carbonic acid)
Ratio of carbonic acid to bicarbonate
1:20
What organ controls bicarbonate levels?
kidneys
What organ controls carbon dioxide?
lungs
How is CO2 formed?
carbohydrate metabolism
Incomplete breakdown of fatty acids that are metabolized are called
ketoacids
Once bicarbonate is in the ECF, it is kept at a level ___ times greater than that of carbonic acid
20
What are buffers composed of?
Chemicals or proteins
Two common chemical buffers?
Bicarbonate and phosphate
Major cell protein buffer?
Hemoglobin
H+ binds to hemoglobin, resulting in fewer H+ ions in the blood, bringing pH back to normal.
Second line of defense when chemical buffers cannot prevent change in blood pH
Respiratory system
Breathing controls Amt of free hydrogen ions by controlling amt of CO2 in arterial blood.
What causes hyperventilation?
CO2 is elevated in brain blood and tissue. Receptors trigger neurons to increase rate and depth of breathing.
What causes hypoventilation?
CO2 in ECF is too low. Respiratory rate and depth are decreased
Which response is faster to balance acid/base?
Respiratory (done within minutes)
How long does it take for kidney’s actions to respond?
24-48 hours
What actions does kidney do for acid/base control?
- Movement of bicarbonate
- Formation of acids
- Formation of ammonium
How is bicarbonate moved in kidneys?
Reabsorbed from kidneys back in to circulation, instead of being excreted in urine.
When does kidney compensation occur?
When respiratory system is overwhelmed or not healthy.
Too many hydrogen ions present is called ___
acidosis
Four processes that can result in metabolic acidosis
- Overproduction of H+ ions
- Undereilmination of H+ ions
- Underproduction of HCO3- ions
- Overelimination of HCO3- ions
Acidosis manifestations - cardiovascular
Increased HR and cardiac output
Decreased HR (as acidosis worsens)
Hypotension
Peripheral pulses may be difficult to find
Acidosis manifestations - CNS
Lethargy
Confusion
Unresponsiveness (as acidosis worsens)
Acidosis manifestation - neuromuscular
Reduced muscle tone & deep tendon reflexes
Acidosis manifestation - respiratory
Deep, rapid breaths (Kussmaul respirations) in metabolic
Shallow and rapid breath in respiratory
Acidosis manifestation - skin
Metabolic: warm, dry pink
Respiratory: pale to cyanotic
Causes of metabolic alkalosis
- Antacid ingestion
- Blood transfusion
- TPN
- Prolonged vomiting (alk alk alkalosis)
Causes of respiratory alkalosis
- Hyperventilation (blowing off too much CO2)
- ASA toxicity
- shock
- High altitudes
Alkalosis manifestation - CNS
dizziness
confusion
hyperreflexia
trousseau and chvostek signs
Alkalosis manifestations - neuromuscular
cramps
twitching
tetany
The symptoms of metabolic and respiratory alkalosis are result of low __ and __
calcium and potassium
Alkalosis manifestations - cardovascular
increased HR
thready pulse
hypotension
Alkalosis manifestations - respiratory
resp rate increased
