Lab Results

• pH 7.35-7.45 (venous 7.31-7.41)
• Pco2 35-45 (venous 40-50)
• HCO3 22-26
• Po2 (arterial) 80-100 mmHg (venous 40-50)

• pH < 7.35
• Pco2 >45
• HCO3 Normal
• Respiratory depression (drugs, CNS trauma). Pulmonary disease (pneumonia, COPD, respiratory underventilation)

• pH >7.45
• Pco2 <35
• HCO3 Normal
• Hyperventilation (emotions, pain, respiratory overventilation)- CO2 is blown off and decreases CO2 levels. pH is inversely proportional. As Pco2 levels rise, brain is usually stimulated to start breathing

• pH < 7.35
• pCO2 Normal
• HCO3 <22
• Diabetes, shock, renal failure, intestinal fistula, diarrhea

• pH >7.35
• Pco2 Normal
• HCO3 > 26
• Sodium bicarbonate overdose, prolonged vomiting, NG drainage

Kidneys will retain increased amounts of HCO; to increase pH

Kidneys will excrete increased amounts of HCO3; to lower pH

Lungs blow off CO2 to raise pH

Lungs retain COs, to lower pH

• Indirectly measures O2 content of arterial blood.
• 1. Pts unable to oxygenate arterial blood bc of O2 diffusion difficulties (pneumonia, shock lung, congestive failure)
• 2. Patients with whom venous blood mixes prematurely with arterial blood (congenital heart disease)
• 3. Patients who have underventilated & overperfused pulmonary alveoli (pickwickian syndrome, ie obese patients who can't breathe properly when supine or patients with atelectasis)

Thyroid abnormalities- increased secretion of calcitonin levels despite hi Ca blood levels

Oat cell carcinoma, pancreatic cancer, breast carcinoma- cancers can produce calcitonin

Hyperparathyroidism- associated with high serum calcium levels

Pernicious anemia, Zollinger-Ellison syndrome

Alcoholic cirrhosis and Thyroiditis