Acid Base & Hypernatremia Flashcards
Henderson Hasselbach formula
pH = pK + log (HCO3/CO2)
- Normal HCO3/CO2 = 20/1
Normals
- pH = 7.35-7.45
- PaCO2 = 40 (35-45)
- HCO3 = 22-26
pH and H+ concentration
- 7.4: 40nEq/lit
- 8: 10nEq/lit
High pH signs
- Irritability
- Arrhythmia
- Seizure
- Death > 7.8
Low pH signs
- Drowsiness
- Coma
Defense mechanism against pH change
-
Buffers 4-5h:
1- Out of cell= HCO3, Proteins (Alb, globulin), inorganic phosphates
2- In cell= HCO3, Hb, Oxyhemoglobulin, organic & inorganic phosphates - Breathing 12-24h
- Kidney 3-4d
Bicarbonate & pH change
10mEq = 0.15 pH
K and pH in metabolic acidosis
0.1 pH decrease = 0.6mEq K increase
Metabolic acidosis
Gastroenteritis
Alcoholic ketoacidosis
DKA
Metabolic alkalosis
Severe vomiting
Furosemide
Acute respiratory acidosis
Sever pneumonia
Chronic respiratory acidosis
COPD
Acute respiratory alkalosis
Mild asthma, Pulmonary edema, Pneumonia
Chronic respiratory alkalosis
Living in high places
Normal pH
Metabolic + Respiratory acidosis
- Severe pulmonary edema
- Arrest
- Poisoning
- Corona + diarrhea
Metabolic acidosis + respiratory alkalosis
ASA poisoning
Sepsis
Liver disease
Metabolic + Respiratory alkalosis
Vomiting + Liver disease
H+ Concentration
[H+] = 24 × PCO2 / [HCO3]
How to know if metabolic or respiratory
1- High pH = Alkalemia
- Low PCO2 Respiratory
- High HCO3 Metabolic
2- Low pH = Acidemia
- High PCO2 Respiratory
- Low HCO3 Metabolic
- If compensated correctly = simple
- If not = mix
Compensations
(-) = decrease
(+) = increase
All same direction
Metabolic Acidosis
(-) 1mEq HCO3 = 1-1.5 mmHg PCO2
Metabolic Alkalosis
(+) 1mEq HCO3 = 0.7 mmHg PCO2
Acute Respiratory Acidosis
(+) 10mmHg PCO2 = 1mEq HCO3
Chronic respiratory acidosis
(+) 10mmHg PCO2 = 3.5mEq HCO3
Acute Respiratory Alkalosis
(-) 10mmHg PCO2 = 2mEq HCO3
Chronic Respiratory Alkalosis(CRA)
(-) 10mmHg PCO2 = 4mEq HCO3
Compensation brings pH to normal in CRA
