NURS 419 - Acid/Base Disorders Study Guide

Flashcards covering key definitions, frameworks, ABG values (ROME method), and compensation mechanisms for acid-base disorders.

What is the relationship between hydrogen ion ($H^+$) concentration and pH in body fluids?

High $H^+$ = low pH (acidic)

Low $H^+$ = high pH (basic)

How do acids and bases differ regarding hydrogen ions?

acid gives

base accepts

What is the primary function of buffers in maintaining acid-base balance?

neutralization = bloods first line of defense against pH changes

Which specific electrolytes are affected by an excess of positively charged $H^+$ ions in respiratory acidosis?

Potassium

calcium

sodium

How do the lungs and kidneys compensate during respiratory alkalosis?

• Breathing will slow down to hold on to carbon dioxide ($CO_2$)

• kidneys will help absorb more hydrogen ($H^+$) to balance the pH

What ratio of bicarbonate to carbonic acid occurs when the buffering system is overwhelmed in metabolic acidosis?

20:1

What causes metabolic alkalosis?

• Prolonged vomiting/nasogastric suction → loss of H+

• Use of diuretics → loss of H+, Na+, K+

• Hyperaldosteronism → ↓ H+ and ↓K+

• Kidney impairment → ↑antacids → excess HCO3- retention

How do pH, $HCO_3^-$, and $PCO_2$ values indicate acid vs. base status?

pH: Low = ACID, High = BASE.

$HCO_3^-$: Low = ACID, High = BASE.

$PCO_2$: Low = BASE, High = ACID.

How do the compensation speeds of the lungs and kidneys compare?

Lungs compensate much faster than the kidneys.

How do the lungs compensate for metabolic acidosis and metabolic alkalosis?

metabolic acidosis = hyperventilation → ↑ pH

metabolic alkalosis = hypoventilation → ↓ pH

How do the kidneys compensate for respiratory acidosis and respiratory alkalosis?

respiratory acidosis = kidneys increase elimination of $H^+$ and increase retention of $HCO_3^-$.

respiratory alkalosis = kidneys decrease elimination of $H^+$ and decrease retention of $HCO_3^-$.

Why does the body aim to maintain a pH between 7.35 to 7.45?

pH below 6.8 or above 7.8 usually fatal

Where can you find the most accurate readings of acid/base lab values and what are normal readings of pH, PaCO₂-, and bicarbonate?

• arterial blood = ABG

• Norma readings

  • pH = 7.35-7.45

  • PaCO2 = 35-45

  • bicarbonate = 22-26

What are causes of respiratory acidosis?

• Drugs: opioids/sedatives → suppresses breathing

• Edema → impaired breathing

• Pneumonia → lung infection

• Respiratory alterations (stroke)

• Emphysema

• Spasms of bronchioles (COPD)

what are symptoms of respiratory acidosis?

• Dizziness, confusion, paresthesias, convulsions, coma

• Cerebral vasoconstriction

• Tetany

What interventions should nurses consider when treating respiratory acidosis?

• Monitor O2/K+/ABG levels, EKG changes

• Administer O2

• Corticosteroids

• Antibiotics

• Reversal agents

what types of treatment help manage respiratory acidosis?

• corticosteroids = improves inflammation

• antibiotics = improves pulmonary function/infection

• bronchodilators = improves airflow/reduces airway resistance

what abnormal ABG readings present for respiratory acidosis?

↓ PH = acid

HCO3- = neutral

↑ PCO2 = acid

How does the body compensate for respiratory acidosis?

kidneys compensate → increase elimination of H+ → increase retention of HCO3-

what abnormal ABG readings present for respiratory alkalosis?

↑ pH = base
HCO3- = neutral
↓ PCO2 = acid

How does the body compensate for respiratory alkalosis?

kidneys compensate → decrease elimination of H+ → decrease retention of HCO3-

what are the causes of respiratory alkalosis?

• increased Temp (fevers)

• Aspirin toxicity

• Controlled ventilation → over breathing

• Hyperventilation

• anxietY → rapid breathing

• Pneumothorax

• Neurological disorders → impaired normal breathing signaling

• pulmonary Embolism → too much CO2 loss

• high Altitude

what are symptoms of respiratory alkalosis?

• vasoconstriction

  • dizziness, confusion, lightheadedness, syncope, paresthesia

• hypcalcemia

  • muscle cramps, twitching, seizures, tetany

• hypokalemia

  • muscle weakness → ↓ cardiac function

What are treatment therapies for respiratory alkalosis?

• Rebreathing → slow down breathing

• Electrolyte imbalance

• Sedatives/anxiety meds

• Teach breathing/relaxation

what abnormal ABG readings present for metabolic acidosis?

↓ PH = acid

↓ HCO3- = base

PCO2 = neutral

How does the body compensate for metabolic acidosis?

lungs compensate → CO2 decreases → pH increases

what are the causes of metabolic acidosis?

• Accumulation of lactate → lactic acidosis → impaired O2

• Chronic diarrhea → loss of HCO3-

• Impaired kidney function

• Diabetic ketoacidosis → (too much acid)

What interventions should nurses consider when treating metabolic acidosis?

DKA

Administer IV fluids as needed

Hemodialysis

Monitor hypokalemia, electrolyte and neuro status

What treatment therapies help with metabolic acidosis?

insulin treatment = ↓ glucose and ketones → ↓ acidity

Dialysis = removes excess acids

what abnormal ABG readings present for metabolic alkalosis?

↑ PH = base

↑ HCO3- = acid

PCO2 = neutral

what are symptoms of metabolic alkalosis?

• neuromuscular excitability

• confusion

• seizures

• tachycardia

• weakness/muscle cramps

what interventions should nurse consider when treating metabolic alkalosis?

Monitor vital signs/electrolyte imbalances

Assess fluid volume/respiratory status

Treat underlying cause