I. RESPIRATORY ACIDEMIA

     A. decreased pH, increased PCO2
     B. Always caused by ALVEOLAR HYPOVENTILATION (decreased VA)
          1. VA = (VT-VD) F
          2. If VA is decreased then either one of the following is present:
               a. decreased Vt
               b. increased VD
               c. decreased Freq

     C. Acute Respiratory Acidemia (no metabolic compensation and HCO3 normal)
          1. Short-term, recent hypoventilation
                    a. Drug over-dose (CNS depression)
                    b. Neuromuscular disease
                    c. Trauma
                    d. Acute bronchospasm

     D. Chronic Respiratory Acidemia marked by increased (metabolic compensation by               increased HCO3)
          1. Long-term alveolar hypoventilation
                    a. increased VD
                    b. decreased VT
                    c. decreased VT

II. RESPIRATORY ALKALEMIA  

     A. Always caused by increased VA
          1. increased VT
          2. increased Freq
          3. decreased VD

     B. Physiologic caused
          1. Hypoxemia
          2.CNS stimulation
          3. Pain, anxiety, fear
          4. Mechanically induced

III. METABOLIC ACIDEMIA

     A. Decreased pH, decreased HCO3
     B. Physiologic causes:
          1. Lactic acidosis
                    a. decreased PaO2
                    b. decreased circulation
                    c. decreased Hg
          2. Ketoacidosis
                    a. Diabetes
                    b. Starvation
                    c.  Alcohol ketoacidosis
          3. Renal Failure
          4. Aspirin OD or other acid type drug

     C. Compensation
          1. By respiratory system
          2. Decrease PaCO2 to bring Ph back to normal

IV. METABOLIC ALKALEMIA
            
     A. increased pH, increased HCO3
     B. Physiologic causes:
          1. Electrolyte imbalance
                    a. Hypokalemia
                    b. Hypochloremia
          2. Vomiting
          3. Diuretics
          4. Massive doses of steroids
          5. Uncontrolled diarrhea

      C. Induced on a compensated respiratory acidemia

          1. COPD – Ph 7.38, CO2 60, HCO3 30
          2. increased ventilation  to bring CO2 down to 40
          3. Ph 7.50, CO2 40, HCO3 30

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