Acid Base Balance

Problems that lead to imbalance

• diabetes

• COPD

• kidney disease

Arterial Blood Gast Test ABG

to detect alterations in the pH of the blood and why the alteration exists and if the body is trying to compensate or correct that alteration and oxygen saturation

pH

7.35-7.45

• measure of H+ ion concentration

• pH can range 1-4

• acidosis < 7.35

• Alkalosis > 7.45

Acid Base Regulation

• metabolic process: produce acids that must be verbalize and excreted

• regulatory mechanisms:

  • buffers

  • respiratory system (CO2)- lungs control CO2

  • Renal System (HCO3)

• the CO2 (lungs) buffers (compensates) the HCO3 (kidneys) and vice versa

Respiratory System Regulation

• respiratory center in medulla controls breathing (responds to increased CO2)

• increased respirations lead to increased CO2 elimination and decreased CO2 in blood

  • decreased respirations lead to increased CO2 retention

• when CO2 increases the kidneys retain HCO3 to compensate HCO3 increase

• When HCO3 decrease, the CO2 decreases to compensate

Renal System Regulation

conserves bicarbonate base and excretes acid

• 3 mechanisms for acid elimination:

  • secretes free hydrogen

  • combine H+ with ammonia (NH3)

  • excrete weak acids

PACO2

35-45

Bicarbonate HCO3

22-26

PaO2

80-100

SaO2

>95%

Acid Base —- R.O.M.E.

• Respiratory

• Opposite

  • alkalosis: (^)pH-(v)PaCO2

  • Acidosis: (v)pH- (^)PaCO2

• Metabolic

• Equal

  • alkalosis: (^)pH- (^)HCO3

  • acidosis: (v)pH- (v)HCO3

(v)pH / (^)CO2 / (-)HCO3

uncompensated respiratory acidosis

(v)pH / (^)CO2 / (^)HCO3

partially compensated respiratory acidosis

(-)pH / (^)CO2 / (^)HCO3

fully compensated respiratory acidosis

Respiratory Acidosis Causes

• decreased respiratory stimuli (anesthesia , drug overdose)

• COPD

• Pneumonia

• Atelectasis

Respiratory Acidosis Manifestations

(v)pH- (^)CO2

• hypoventilation= hypoxia

• rapid, shallow respirations

• decreased BP vasodilation

• dyspnea

• Drowsiness, dizziness, disoriention, headache

• hyperkalemia

• Dysrhytmias (^ K)

• muscle weakness, hyperflexia

Respiratory Alkalosis: Causes

• hyperventilation (anxiety, PE, Fear)

• mechanical ventilation

(^)pH / (v)CO2 / (-)HCO3

uncompensated respiratory alkalosis

(^)pH / (v)CO2 / (v)HCO3

partially compensated respiratory alkalosis

(-)pH / (v)CO2 / (v)HCO3

full compensated respiratory alkalosis

Respiratory Alkalosis: Manifestations

• Deep, rapid breathing

• seizures, lethargy, confusion

• light headedness

• numbness and tingling of extremeties

• nausea, vomiting

• tachycardia

• decreased or normal BP

• Hypokalemia

(v)pH / (-)CO2 / (v)HCO3

uncompensated metabolic acidosis

(v)pH / (v)CO2 / (v)HCO3

partially compensated metabolic acidosis

(-)pH / (v)CO2 / (v)HCO3

fully compensated metabolic acidosis

Metabolic Acidosis Causes

• DKA

• Severe Diarrhea

• Renal Shock

Metabolic Acidosis: Manifestation

• headache, N/V/D

• Decreased BP (hypotension)

• Hyperkalemia

• muscle twitching

• changes in LOC (confusion, drowsiness)

• Kussmaul Respirations (compensatory hyperventilation)

(^)pH / (-)CO2 / (^)HCO3

uncompensated metabolic alkalosis

(^)pH / (^)CO2 / (^)HCO3

partially compensated metabolic alkalosis

(-)pH / (^)CO2 / (^)HCO3

fully compensated metabolic acidosis

Metabolic Acidosis: causes

• severe vomitting

• excessive GI suctioning

• Diuretics

• Excessive NaHCO3

Metabolic Acidosis: Manifestations

• restlessness follow by lethargy

• confusion (decrease LOC, dizzy, irritable)

• dysrhythmias (tachycardia)

• N/V/D

• compensatory Hypoventilation

• tremors, muscle cramps, tingling of fingers and toes

• hypokalemia