Acid-Base Balance pt 3

What two main mechanisms cause metabolic acidosis?

Excess acid accumulation (↓ pH) or loss of alkali/base (↓ HCO₃⁻).

How does renal failure cause metabolic acidosis?

Impaired acid excretion leads to acid accumulation and decreased pH.

Why does diabetic ketoacidosis (DKA) cause metabolic acidosis?

Ketone body accumulation increases metabolic acids.

How does anaerobic metabolism lead to metabolic acidosis?

Lactic acid production increases during hypovolemic shock or sepsis.

How does starvation cause metabolic acidosis?

Fat breakdown produces ketones, increasing acid levels.

How does aspirin (salicylate) intoxication cause metabolic acidosis?

Salicylates increase acid production and disrupt acid–base balance.

How does diarrhea lead to metabolic acidosis?

Loss of bicarbonate-rich intestinal fluids decreases HCO₃⁻.

How do intestinal fistulas cause metabolic acidosis?

Excessive bicarbonate loss lowers serum HCO₃⁻.

How is metabolic acidosis treated overall?

Treatment depends on the underlying cause.

When is IV sodium bicarbonate used in metabolic acidosis?

To neutralize severe blood acidity.

Why is IV fluid replacement important in metabolic acidosis?

To restore circulating volume and improve perfusion.

What medication is used to treat metabolic acidosis caused by DKA?

Rapid-acting insulin.

What treatment is used for diarrhea-related metabolic acidosis?

Anti-diarrheal medications.

When is dialysis indicated in metabolic acidosis?

In severe renal failure or toxin accumulation.

What laboratory values must be monitored in metabolic acidosis?

Blood glucose and serum electrolytes.

When may mechanical ventilation be required in metabolic acidosis?

If respiratory compensation is inadequate or the patient is in distress.

What ongoing assessments are essential in metabolic acidosis?

Monitoring vital signs.

What causes metabolic alkalosis?

Increased loss of acid or fluid.

How does a patient with metabolic alkalosis often appear?

Dry and volume-depleted (“dry & empty”).

What is the most common route of acid loss in metabolic alkalosis?

Gastrointestinal tract or renal excretion.

Which GI conditions commonly cause metabolic alkalosis?

Vomiting or nasogastric suctioning.

What lab values define metabolic alkalosis?

Arterial pH > 7.45 and HCO₃⁻ > 26 mEq/L.

How does the body compensate for metabolic alkalosis?

Hypoventilation to conserve PaCO₂.

Why does metabolic alkalosis cause hypokalemia?

Potassium shifts into cells in exchange for hydrogen ions.

What are the two main mechanisms that cause metabolic alkalosis?

Gain of base or loss of acids.

How does excess bicarbonate use cause metabolic alkalosis?

It increases base levels, raising arterial pH.

How can lactate administration during dialysis cause metabolic alkalosis?

Lactate is converted to bicarbonate, increasing base levels.

How does excessive antacid use contribute to metabolic alkalosis?

Overuse increases bicarbonate, raising blood pH.

How does vomiting cause metabolic alkalosis?

Loss of gastric acid increases blood pH.

Why does nasogastric suctioning lead to metabolic alkalosis?

Continuous removal of gastric acid causes acid loss.

How does hypokalemia contribute to metabolic alkalosis?

Hydrogen ions shift into cells to compensate, increasing blood pH.

How does hypochloremia contribute to metabolic alkalosis?

Chloride loss impairs bicarbonate excretion, increasing alkalosis.

How do diuretics cause metabolic alkalosis?

They promote loss of hydrogen and chloride ions.

How does increased aldosterone contribute to metabolic alkalosis?

Aldosterone promotes sodium retention and hydrogen ion loss.

What neurological symptoms are seen in metabolic acidosis?

Confusion, lethargy, stupor, coma, restlessness, seizures.

What neuromuscular symptoms occur in metabolic acidosis?

Weakness and twitching.

What respiratory pattern is associated with metabolic acidosis?

Kussmaul’s respirations.

What gastrointestinal symptoms are associated with metabolic acidosis?

Nausea and vomiting.

What cardiovascular and skin findings occur in metabolic acidosis?

Dysrhythmias, peripheral vasodilation, and warm, flushed skin.

What neuromuscular symptoms are associated with metabolic alkalosis?

Muscle twitching, cramps, tetany, and convulsions.

What neurological symptoms occur in metabolic alkalosis?

Dizziness, disorientation, lethargy, coma, and weakness.

What gastrointestinal symptoms are seen in metabolic alkalosis?

Nausea and vomiting.

What respiratory change occurs in metabolic alkalosis?

Depressed respirations.

How is metabolic alkalosis generally treated?

Treatment depends on the underlying cause.

Which medications or therapies should be discontinued in metabolic alkalosis?

Potassium-wasting diuretics, nasogastric suctioning, and antacids.

What medication is used to manage nausea and vomiting in metabolic alkalosis?

Antiemetics.

Why should oxygen saturation be monitored in metabolic alkalosis?

To detect hypoxia.

What vital assessments are essential during treatment of metabolic alkalosis?

Monitoring vital signs.

Which laboratory values should be monitored in metabolic alkalosis?

Blood glucose and serum electrolytes.

Why is cardiac rhythm monitoring important in metabolic alkalosis?

To detect EKG changes and dysrhythmias.

What neurological assessment is important in metabolic alkalosis?

Assessing level of consciousness.

Why are IV fluids often administered in metabolic alkalosis?

To correct fluid and electrolyte imbalances.

What defines an uncompensated acid–base disorder?

Abnormal pH with either abnormal HCO₃⁻ or CO₂ while the other value remains normal.

What does a normal HCO₃⁻ or CO₂ indicate in uncompensated imbalance?

The opposing system has not begun compensating yet.

What defines partial compensation?

pH, CO₂, and HCO₃⁻ are all abnormal.

What defines full (complete) compensation?

pH is normal, but CO₂ and HCO₃⁻ remain abnormal.

How do you identify respiratory acidosis in ABG values?

pH is acidic (<7.35) and PaCO₂ is elevated.

What ABG values indicate respiratory acidosis with partial compensation?

pH 7.32, PaCO₂ 52, HCO₃⁻ 30.

Why is bicarbonate elevated in compensated respiratory acidosis?

The kidneys retain bicarbonate to help correct the acidosis.

Why is this considered partial compensation?

The pH is still abnormal despite increased bicarbonate.

What ABG values indicate fully compensated metabolic acidosis?

pH 7.36 (normal), HCO₃⁻ 18 (↓), PaCO₂ 30 (↓).

How do you identify the primary disorder in fully compensated metabolic acidosis?

The bicarbonate (HCO₃⁻) is low, indicating a metabolic problem.

Which system compensates for metabolic acidosis in full compensation?

The lungs compensate by decreasing PaCO₂.

Why is the pH normal in fully compensated metabolic acidosis?

Respiratory compensation has corrected the pH.

Why is this condition considered fully compensated?

The pH is normal even though both HCO₃⁻ and PaCO₂ are abnormal.

What ABG values indicate uncompensated respiratory acidosis?

pH 7.28 (↓), PaCO₂ 55 (↑), HCO₃⁻ 24 (normal).

How do you identify respiratory acidosis from ABG values?

The pH is acidic and PaCO₂ is elevated.

Why is this respiratory acidosis considered uncompensated?

Bicarbonate (HCO₃⁻) remains normal, showing no renal compensation yet.