Respiratory Acidosis

Respiratory acidosis is a critical acid-base imbalance that demands vigilant monitoring and prompt nursing interventions. As a common occurrence in various clinical conditions, understanding the underlying pathophysiology, recognizing clinical manifestations, and implementing effective nursing care are paramount to improve patient outcomes. This article aims to provide nurses with a comprehensive overview of respiratory acidosis, empowering them to confidently assess, manage, and support patients afflicted by this complex disorder.

Table of Contents

• What is Respiratory Acidosis?
• Causes
• Complications
• Signs and Symptoms
• Assessment
• Diagnostic Studies
• Nursing Diagnosis
• Nursing Priorities
• Discharge Goals
• Care Setting
• Nursing Care Plans
• Nursing Interventions & Considerations
• See Also

What is Respiratory Acidosis?

Respiratory Acidosis is an acid-base imbalance characterized by increased partial pressure of arterial carbon dioxide and decreased blood pH. The prognosis depends on the severity of the underlying disturbance as well as the patient’s general clinical condition.

Compensatory mechanisms include (1) an increased respiratory rate; (2) hemoglobin (Hb) buffering, forming bicarbonate ions and deoxygenated Hb; and (3) increased renal ammonia acid excretions with reabsorption of bicarbonate.

Acute respiratory acidosis: Associated with acute pulmonary edema, aspiration of foreign body, overdose of sedatives/barbiturate poisoning, smoke inhalation, acute laryngospasm, hemothorax/pneumothorax, atelectasis, adult respiratory distress syndrome (ARDS), anesthesia/surgery, mechanical ventilators, excessive CO₂ intake (e.g., use of rebreathing mask, cerebral vascular accident [CVA] therapy), Pickwickian syndrome.

Chronic respiratory acidosis: Associated with emphysema, asthma, bronchiectasis; neuromuscular disorders (such as Guillain-Barré syndrome and myasthenia gravis); botulism; spinal cord injuries.

Causes

• Chronic obstructive respiratory disorders: emphysema, chronic bronchitis
• Chest wall trauma
• Pulmonary edema
• Atelectasis
• Pneumothorax
• Drug Overdose
• Pneumonia
• Guillain-Barre syndrome

Complications

• Shock
• Cardiac Arrest

Signs and Symptoms

• CNS disturbances: restlessness, confusion, and apprehension to somnolence with fine flapping tremor, or coma.
• Headache
• Dyspnea
• Tachypnea
• Increase in blood pressure
• Mental cloudiness and feeling of fullness in head
• Weakness

Assessment

Assessment cues are dependent on underlying cause.

ACTIVITY/REST

• May report: Fatigue, mild to profound
• May exhibit: Generalized weakness, ataxia/staggering, loss of coordination (chronic), to stupor

CIRCULATION

• May exhibit: Low BP/hypotension with bounding pulses, pinkish color, warm skin (reflects vasodilation of severe acidosis)
• Tachycardia, irregular pulse (other/various dysrhythmias)
• Diaphoresis, pallor, and cyanosis (late stage)

FOOD/FLUID

• May report: Nausea/vomiting

NEUROSENSORY

• May report: Feeling of fullness in head (acute—associated with vasodilation)
• Headache, dizziness, visual disturbances
• May exhibit: Confusion, apprehension, agitation, restlessness, somnolence; coma (acute)
• Tremors, decreased reflexes (severe)

RESPIRATION

• May report: Shortness of breath; dyspnea with exertion
• May exhibit: Respiratory rate dependent on underlying cause, i.e., decreased in respiratory center depression/
• muscle paralysis; otherwise rate is rapid/shallow
• Increased respiratory effort with nasal flaring/yawning, use of neck and upper body muscles
• Decreased respiratory rate/hypoventilation (associated with decreased function of respiratory center as in head trauma, oversedation, general anesthesia, metabolic alkalosis)
• Adventitious breath sounds (crackles, wheezes); stridor, crowing

TEACHING/LEARNING

• Refer to specific plans of care reflecting individual predisposing/contributing factors.

Diagnostic Studies

• CONFIRMING DIAGNOSIS: Arterial blood gas (ABG) analysis of
  • PaCO2 higher than 45 mm Hg
  • pH is below normal range of 7.35 to 7.45
  • bicarbonate level is normal (acute) or elevate (in chronic stages)
• Chest X-ray, CT scan can help determine the cause
• ABGs: Pao₂: Normal or may be low. Oxygen saturation (Sao₂) decreased.
• Paco₂: Increased, greater than 45 mm Hg (primary acidosis).
• Bicarbonate (HCO₃): Normal or increased, greater than 26 mEq/L (compensated/chronic stage).
• Arterial pH: Decreased, less than 7.35.
• Electrolytes: Serum potassium: Typically increased.
• Serum chloride: Decreased.
• Serum calcium: Increased.
• Lactic acid: May be elevated.
• Urinalysis: Urine pH decreased.
• Other screening tests: As indicated by underlying illness/condition to determine underlying cause.

Nursing Diagnosis

The following are the possible nursing diagnosis for Respiratory Acidosis:

• Impaired Gas Exchange
• Ineffective Breathing Pattern
• Ineffective Tissue Perfusion
• Acute Confusion
• Risk for Injury

Nursing Priorities

1. Achieve homeostasis.
2. Prevent/minimize complications.
3. Provide information about condition/prognosis and treatment needs as appropriate.

Discharge Goals

1. Physiological balance restored.
2. Free of complications.
3. Condition, prognosis, and treatment needs understood.
4. Plan in place to meet needs after discharge.

Care Setting

This condition does not occur in isolation, but rather is a complication of a broader health problem/disease or condition for which the severely compromised patient requires admission to a medical-surgical or subacute unit.

Nursing Care Plans

Main Article: Respiratory Acidosis Nursing Care Plan

Nursing Interventions & Considerations

• Remain alert for critical changes in patient’s respiratory, CNS and cardiovascular functions. Report such changes as well as any variations in ABG values or electrolyte status immediately.
• Maintain adequate hydration.
• Maintain patent airway and provide humidification if acidosis requires mechanical ventilation. Perform tracheal suctioning frequently and vigorous chest physiotherapy, if ordered.
• Institute safety measures and assist patient with positioning.
• Continuously monitor arterial blood gases.

See Also

• Acid-Base Imbalances
• Respiratory Acidosis Nursing Care Plan