Acid Base Balance Body

ACID BASE BALANCE BODY

1. Acid-base balance is the homeostasis of the hydrogen ion concentration in the body
2. Normal levels of hydrogen ions (H) arteries are: 4x10-8 or pH = 7.4 (7.35 to 7.45)
3. Acidosis = acidemia → blood pH levels <7.35 Alkalemia = alkalosis → blood pH levels> 7.45
4. Levels of blood pH <6.8 or> 7.8 can not be resolved by the body

Body Buffer System

• ECF buffer System → carbonic acid-bicarbonate (NaHCO3 and H2CO3)
• ICF buffer System → monosodium-disodium phosphate (Na2HPO4 and NaH2PO4)
• ICF buffer system → oxyhemoglobin-erythrocyte hemoglobin (HbO2- and HHB)
• ICF and ECF buffer system → protein (PR- and HPR)

• Defence normal blood pH is achieved through the combined work of the buffer the blood, lungs and kidneys
• Handerson Hasselbach equation:

                           20 [HCO3-]

pH = 6.1 + log ---------------------

                           1PaCO2

• [HCO3-] → metabolic factors, kidney controlled
• PaCO2 → respiratory factor, controlled lung
• → pH 6.1 buffer effect of carbonic acid-bicarbonate
• During the comparison [HCO3-]: PaCO2 = 20: 1 → pH of blood is always = 6.1 + 1.3 = 7.4

Acid Alkali blood disorders

• Metabolic acidosis [HCO3-] is compensated with PaCO2 ↓ ↓
• Metabolic alkalosis [HCO3-] is compensated with PaCO2 ↑ ↑
• ↑ compensated respiratory acidosis PaCO2 with [HCO3-] ↑
• ↓ PaCO2 respiratory alkalosis compensated by [HCO3-] ↓

Metabolic acidosis

• Feature: [HCO3-] ↓ <22mEq / L and pH <7.35 → ↓ PaCO2 compensated by hyperventilation, final compensation renal excretion → H +, as NH4 + or H3PO4
• Cause: The addition of acid is fixed: diabetic ketoacidosis, lactic acidosis (cardiac arrest or shock), an overdose of aspirin Kidney failure to excrete acid load loss of HCO3- bases → diarrhea
• Symptoms of Metabolic Acidosis is not clear and asymptomatic Cardiovascular: dysrhythmias, decreased contraction of the heart, peripheral and cerebral vasodilation Neurological: lethargy, stupor, coma Respiratory: hyperventilation (Kussmal) Changes in bone function: renal osteodystrophy (adult) and retardation in children
• Management of Metabolic Acidosis Objective: improve the blood pH down to a safe level (7.20 to 7.25) and treat the underlying disease NaHCO3 can be used when the pH <7.2 or [HCO3-] <15mEq / L
• NaHCO3 excessive risk: central emphasis of breath, respiratory alkalosis, tissue hypoxia, metabolic alkalosis, hypocalcemia, cramps, tetany Metabolic alkalosis Feature: [HCO3-] ↑> 26mEq / L and pH> 7.45 → ↑ PaCO2 compensated by hypoventilation, compensation → end by renal excretion of [HCO3-] excessive

Cause:

• Loss of H + (vomiting, diuretics, transfer of H + from ECF to ICF in hypokalemia)
• Retention [HCO3-] (metabolic acidosis post hypercapnia)

Symptoms of Metabolic alkalosis

• Symptoms and signs are not specific
• Convulsions and muscle weakness due to hypokalemia and dehydration →
• Cardiac dysrhythmias, ECG abnormalities → hypokalemia
• Paresthesias, muscle spasms → hypocalcemia

Management of Metabolic alkalosis

• Objective: to eliminate the basic disease
• Giving IV KCl in 0.9% saline → (given if the urine Cl <10mEq / L) removes incentives 
  → aldosterone excretion of urine NaHCO3 If Cl> 20 mEq / L → → caused excessive aldosterone can not be treated with IV saline, but with diuretics.

Respiratory acidosis

• Feature: ↑ PaCO2> 45mmHg and pH <7.35 → renal compensation retention and an increase in [HCO3-]
• Cause: hypoventilation (CO2 retention), central inhibition of breath (an overdose of sedatives, cardiac arrest), diseases of the chest wall muscles and breath (fracture costae, miastemia gravis), gas exchange disorder (COPD), upper airway obstruction
• Symptoms of Respiratory acidosis No specific hypoxemia (dominant) → acute respiratory acidosis due to somnolence progressive airway obstruction, chronic respiratory acidosis coma → → improve cerebral vasodilatation ICV → papilledema and headache
• Management of Respiratory acidosis effective ventilation recovery as soon as possible → Award O2 and treat the causes of underlying disease should be improved PaO2> 60mmHg and pH> 7.2

Respiratory alkalosis

• Feature: decrease PaCO2 <35mmHg and increased serum pH> 7.45 → renal compensation increases the excretion of HCO3-
• Cause: hyperventilation (common psychogenic because of stress and anxiety), hypoxemia (pneumonia, congestive heart failure, hipermetabolik (fever), stroke, early stage aspirin poisoning, septicemia

Symptoms of Respiratory alkalosis

• Hyperventilation (gas levels, frequency of breath)
• Yawning, urgent, find it difficult to breathe
• Anxiety: dry mouth, palpitations, fatigue, palms and feet cold and sweaty
• Paresthesia, muscle twitching, tetany
• Serebal cerebral hypoxic vasoconstriction → → head cold and hard concentration

Management of Respiratory alkalosis

• Eliminate the basic causes
• Anxiety can be removed with a paper bag breathing tightly held around the nose and mouth can recover acute attacks
• Hyperventilation mechanical ventilation menurangi → coped with in a minute, add the vacuum or inhale 3% CO2 in a short time.