Acid Base Flashcards
Acid-Base Regulation
Buffer system (immediate) Respiratory system (minutes to hours) Renal system (2-3 days)
Buffer system
Electrolyte exchange in cells (K-H)
Major organs (lungs and kidneys)
Lungs - CO2
Kidneys - acids and bicarbonate
Alkalosis
hypokalemia
Acidosis
Hyperkalemia
kidneys
excrete H+ and reabsorb HCO3 to increase pH in respiratory acidosis
Respiratory Acidosis
Causes
- COPD or asthma
- barbituate or sedative overdose
- severe pneumonia
- Atelectasis
- Respiratory muscle weakness
- mechanical hypoventilation
- sleep apnea
- head trauma
- post operative
- CNS depression
Increased PCO2 and decreased pH if uncompensated
Respiratory Acidosis
Manifestations
- Neurological – drowsiness, disorientation, dizziness, headache, coma
- Cardiovascular – ↓BP; ventricular fibrillation; warm, flushed skin (peripheral vasodilation)
- GI – no significant findings
- Neuromuscular – seizures
- Respiratory - dyspnea, hypoventilation with hypoxia
Respiratory Acidosis
Interventions
Treat underlying cause: opioids, oxygen therapy
Respiratory Alkalosis
Causes
- Anything causing hyperventilation: hypoxia, fear/anxiety, fever, Fast resps
- Stimulated respiratory center: CNS disorders, sepsis, brain injury, salicylate poisoning
- Mechanical overventilation
Decreased PaCO2 and increased pH if uncompensated
Respiratory Alkalosis
Manifestations
- Neurological – lethargy, lightheadedness, confusion
- Cardiovascular – increased HR; dysrhythmias
- GI - nausea, vomiting, epigastric pain
- Neuromuscular – tetany (muscle contraction), numbness, tingling of extremities, hyperreflexia, seizures
- Respiratory – rapid, shallow breathing
Respiratory Alkalosis
Interventions
Treat underlying cause: rebreather mask, assist client to slow resps, decrease anxiety, oxygen therapy if hypoxia is the underlying cause
monitor VS, ABGs and electrolyte imbalances
Metabolic Acidosis
Causes
Accumulation of acid: DKA, septic shock (lactic acid accumulation), starvation, renal failure, diarrhea
Loss of bicarbonate: diarrhea, renal failure
Decreased HCO and decreased pH if uncompensated
Metabolic acidosis
Manifestations
• Neurological – drowsiness, confusion, headache, coma
• Cardiovascular - ↓ BP; dysrhythmias; warm, flushed skin (peripheral vasodilation)
• GI – nausea, vomiting, diarrhea, abdominal pain
• Neuromuscular – no significant findings
• Respiratory – deep, rapid respirations (Kussmaul’s respiration)
Interventions
• Treat underlying cause
• Respiratory support
• Administer sodium bicarbonate (?) – IV to neutralize done later on
Metabolic Alkalosis
Causes
Loss of acid: NG suctioning, prolonged vomiting, loss of K+ due to diuretic therapy
Gain in bicarbonate: ingestion of baking soda
Metabolic Alkalosis
Manifestations
- Neurological – dizziness, irritability, nervousness, confusion
- CVS – tachycardia, dysrhythmias
- GI – anorexia, nausea, vomiting
- Neuromuscular – tremors, hypertonic muscles, muscle cramps, tetany, tingling of fingers & toes
- Respiratory – hypoventilation (↓RR)
Metabolic Alkalosis
Interventions
Treat underlying cause: replace lost fluids and electrolytes (MG and K), support renal function (dialysis if needed)
Administer acetazolamide - promotes loss of bicarbonate in urine
Mixed
2 or more simple disorders present at the same time
pH will depend on type, severity and acuity (resp acidosis and metabolic alkalosis) Mixed acidosis (cardiopulmonary arrest) Mixed Alkalosis (hyperventilating and NG suctioning)
