2.6

• Normal arterial blood pH

  7.40
• Normal arterial blood pH range

  7.35 - 7.45
• pH level less than 7.35

  Acidosis
• pH level greater than 7.45


  Alkalosis
• To decrease PaCO2 levels (Correct Hypercapnia)

  Increase Vt, F, Ve
• To increase PaCO2 levels (Correct Hypocapnia)

  Decrease Vt, F, Ve
• Goal for mechanical ventilatory support


  To rapidly achieve a normal or near normal PaCO2 and pH for that patient
• Patients in respiratory acidosis present with a decreased respiratory drive
• How Respiratory Acidosis occurs

  Pain, chronic elevations, decreased metabolic rate, electrolyte disorders, neurological disorders, CNS depressants, respiratory or metabolic alkalosis
• How to correct Respiratory Acidosis

  Increase Ve or inspiratory pressure
• Patients in respiratory alkalosis present with an increased respiratory drive
• How Respiratory Alkalosis occurs


  Hypoxemia, metabolic acidosis, increased CO2 production, lung receptor stimulation, pain, anxiety, decreased blood pressure
• How to correct Respiratory Alkalosis

  Decrease Ve
• Causes of metabolic acidosis

  • Lactic acidosis, acute severe hypoxia, cardiac arrest, cardiac failure, hypovolemia, sepsis, shock, ketoacidosis, kidney failure, ingestion of acids, diarrhea, pancreatic fluid, IV hyperalimenation
• Normal physiologic response to metabolic acidosis

  Hyperventilation
• How to correct metabolic alkalosis

  Inform RN, or physician
• Causes of metabolic alkalosis

  • Vomiting, Renal loss of hydrogen ions, hypokalemia, hypovolemia, sodium bicarbonate admin, NG tube suction
• Most common cause of metabolic alkalosis

  Hypokalemia and volume depletion
• To treat fluid retention

  Administer diuretics