Acid Base Regulation Flashcards
What does metabolism generate a lot of?
A lot of H+
Which disorders affect acid base balance?
Disorders that affect respiratory performance/renal function or digestive system (asthma, emphysema,renal failure)
Why do babies have greater challenges with acid base balance?
Due to immature kidneys and greater metabolic rates
Why is acid base balance important?
PH affects protein structure and function (eg- enzymes)
How do buffers help stabilise Ph?
They bind excess H+ (eg- Hb, albumin) phosphate buffers H+ in plasma and extra cellular fluid
What type of compensation brings plasma pH back to normal?
Renal compensation and respiratory compensation
Is renal compensation fast?
No it’s a sensitive but slow process
Respiratory compensation?
Less sensitive but rapid
Give examples of respiratory compensation:?
Breathing rapidly eliminates CO2 (lowers blood pH)
Reduces blood bicarbonate
Raises blood pH
Renal compensation examples:
Eliminate H+ from CO2 and NH4+ into urine effectively but slowly
Renal tubule cells secrete H+ into urine via ATPase ion pumps
Urine H+ can be 1000 more acidic than blood
Name 4 types of acid base imbalances?
- respiratory acidosis
- Respiratory alkalosis
- Metabolic acidosis
- Metabolic alkalosis
Explain respiratory acidosis?
Most common type: when respiratory system can’t eliminate enough CO2
Blood is too acidic
Acute causes of respiratory acidosis?
Can be caused by breath holding
Chronic causes of respiratory acidosis?
Can be caused by airways obstructions, problems with medulla respiratory centres, lung diseases
Renal compensation for respiratory acidosis?
Increased excretion of H+, reabsorption of HCO3-
Treatment: increase breathing rate/ use bronchodilators
Respiratory alkalosis?
- quite uncommon: when blood is too alkali
- Low PCO2
Acute causes of Respiratory alkalosis?
- Voluntary: blowing up balloons
- severe anxiety
- Entering cold water
- Fever
- Aspirin overdose
Chronic causes of respiratory alkalosis?
Hypoxia (Low O2) due to living at high altitudes
- stroke
- liver failure
Renal compensation for respiratory alkalosis:
(PCO2 still remains slow):
Decreases excretion of H+
Reduced reabsorption of HCO3-
Treatment: controlled breathing/ rebreathe air into a paper bag
Metabolic acidosis?
Quite common- Low arterial HCO3 and low PH
Caused by:
acid accumulation due to diabetic/starvation
Renal failure
And loss of HCO3 due to severe diarrhoea
Respiratory compensation for metabolic acidosis?
Rapid hyperventilation increases loss of CO2
Renal compensation eliminates more H+ in urine
Treatment: intravenous HCO3
Metabolic alkalosis?
High arterial HCO3, High PH
Caused by loss of acid due to vomiting, gastric suctioning, excess aldosterone
Caused by loss of base: intake of alkaline drugs
Respiratory compensation for metabolic alkalosis
Hypoventilation to decrease loss of CO2
Treatment: ammonium chloride: generates G+ and Cl-
