1	Acid/Base Balance & Blood Gases
2	Acid/Base balance Talking about the hydrogen ion concentration. This is the acidic portion. Concentration of the bicarbonate ion is the alkaline portion. The body is balance when there is one part hydrogen to twenty parts bicarbonate
3	PH scale: 7.0 is neutral 6.8 to 7.8 is compatible with life normal is 7.35 to 7.45 below 7.35 is considered acidic above 7.45 is considered alkaline acidic patient will have a depressed CNS alkaline patient will have an over stimulated CNS
4	Three regulatory systems for acid/base Buffer System Respiratory System Renal System
5	buffer system Works within seconds. It utilizes three chemicals: bicarbonate, phosphate, and protein.
6	Respiratory system Works within several minutes to several hours. When there is extra hydrogen ions, they combine with carbon dioxide. Respiratory rate and depth is increased. When the pH is up, the respiratory rate and depth is decreased.
7	Renal system Controls long-term management. It may take up to 2 to 3 days to start working. It cleans up and maintains the balance. For the elderly, it may take longer due to the decrease in renal function. The kidneys will excrete the unneeded hydrogen ion or the unneeded bicarbonate. The pH of normal urine is 6.0. Urine is normally always acidic. The patient with acidosis, the output will be increased. The patient who is alkalotic, there is not enough hydrogen ion. The kidneys try to save the hydrogen ions. There will be decreased urinary output and the pH of the urine will go up.
8	Lab values for blood gasses pH 7.35 to 7.45 pO₂ 80 to 110 pCO₂ 35 to 45 Bicarbonate 22 to 26
9	Arterial Blood Gases
10	Lab values for blood gasses pH 7.35 to 7.45 pO₂ 80 to 110 pCO₂ 35 to 45 HCO₃^- 22 to 26
11	Blood Gas Value Movement The CO₂ and pH will move in opposite directions. Bicarbonate and pH will move in the same direction. pCO₂ and pH move in opposite directions HCO₃^- and pH move in the same direction
12	Blood Gas Analysis Review the pH and determine acidosis or alkalosis. Review the CO₂ and HCO₃^- If the CO₂ is altered, it is respiratory If the HCO₃ is altered, it is metabolic If all three values are abnormal, compensation is occurring
13	Respiratory Acidosis
14	Etiology COPD Any conditions that cause the patient to not be able to breathe properly (chest wall surgery, obesity, pneumonia, over dosage of sedatives or anesthetics) Any dyspnea leads to a risk for respiratory acidosis. Arterial CO₂ will probably be above 45
15	Signs and symptoms Dizzy Drowsy Hypotensive Headache Muscle weakness EKG may show ventricular dysrhythmias Tachypnea and shallow respirations
16	Lab values ABG pH will be low CO₂ will be high HCO₃^- will be normal if compensation has not taken place HCO₃^- will be high if compensation has taken place Urine pH will be lower (<6).
17	Respiratory Alkalosis
18	Etiology Results in the lack of carbonic acid in the body There is excessive pulmonary ventilation to cause it. States of hypoxia early in the progression of the hypoxic episode High altitude Anxiety Pain Excessive exercise High fever Septicemia Encephalitis Overdose of aspirin Mechanical over ventilation
19	Signs and symptoms Pathophysiology of hyperventilation syndrome Tachycardia with progression to dysrhythmias Abdominal pain, probably from using accessory muscles to breathe
20	Labs pH will be high CO₂ will be low Bicarbonate (HCO₃^-) will be normal in uncompensated Bicarbonate (HCO₃^-) will be down in compensated Urine pH will be up
21	Metabolic Acidosis An acid other than carbonic acid accumulates in the body or when bicarbonate is lost from the body
22	Etiology DKA Starvation (lactic acid builds up) Severe diarrhea Renal failure GI fistulas
23	Signs and symptoms Lethargic Weak Dull headache Nausea and vomiting Abdominal pain Confused to unconscious Bradycardia Deep and rapid respirations
24	Labs pH will be down Bicarbonate (HCO₃^-) will be down Uncompensated, the CO₂ will be normal Compensated, the CO₂ will be down Compensated, the urine pH will low
25	Compensation Kidneys try to conserve bicarbonate and excrete hydrogen ions
26	Metabolic Alkalosis
27	Etiology Overdose of bicarbonate Loss of chloride through gastric suctioning or vomiting Potassium deficit
28	Signs and symptoms Irritable and nervous Tachycardic Dysthythmias Anorexia, nausea, vomiting Hypertonic muscles to tetany and seizures Slow respirations
29	Lab values Arterial pH is up Bicarbonate is up CO₂ is normal in uncompensated CO₂ is up in compensated Urine In compensation pH will go up
30	Normal Blood Gas Values pH 7.35 – 7.45 pO₂ 80 – 110 pCO₂ 35 – 45 HCO₃^- 22 – 26
31	CO₂ and pH move in opposite directions
32	HCO₃^- and pH move in the same direction
33	Altered CO₂ = Respiratory condition
34	Altered HCO₃^- = Metabolic condition