NCLEX: Respiratory Nursing Review

The respiratory system is the engine of human physiology, and its failure is a leading cause of clinical deterioration. For the NCLEX-RN®, mastery of respiratory nursing is non-negotiable; you must be able to move seamlessly from subtle assessment cues to life-saving interventions.

Foundational Assessment: The Bedside Exam

Your respiratory assessment is the first and most critical diagnostic tool. It begins with observation: note the patient's work of breathing, which includes the use of accessory muscles (neck, shoulders), nasal flaring, or a paradoxical chest wall movement. Listen for audible sounds like stridor (a high-pitched inspiratory sound indicating upper airway obstruction) or wheezing (a whistling expiratory sound often associated with bronchoconstriction).

Auscultation of breath sounds provides direct clues to underlying pathology. You must recognize these key types:

• Vesicular: Soft, low-pitched sounds heard over most lung fields. Their absence can indicate consolidation or pleural effusion.
• Bronchial: Loud, high-pitched, tubular sounds heard normally over the trachea. Hearing them over peripheral lung fields suggests consolidation, as in pneumonia.
• Wheezes: Continuous musical sounds caused by air moving through narrowed airways (e.g., asthma, COPD).
• Crackles (Rales): Discontinuous, popping sounds heard during inspiration, often likened to Velcro opening. Fine crackles may suggest pulmonary edema, while coarse crackles can indicate secretions.
• Diminished or Absent: Can signify atelectasis, pneumothorax, or pleural effusion.

NCLEX Tip: The exam will often give you breath sound findings and ask for the corresponding condition or the next nursing action. Always correlate findings with other data, like vital signs and pulse oximetry readings.

Oxygen Therapy and Delivery Systems

Understanding the precise amount of oxygen you are delivering is paramount. Systems are categorized as low-flow or high-flow. Low-flow systems (e.g., nasal cannula, simple face mask) deliver oxygen at a rate lower than the patient's inspiratory flow rate, meaning the delivered FiO2 (Fraction of Inspired Oxygen) varies with the patient's breathing pattern. A nasal cannula delivers 24-44% FiO2 at 1-6 L/min.

High-flow systems deliver a precise FiO2 at a flow rate that meets or exceeds the patient's inspiratory demand. A Venturi mask is a high-flow device that uses color-coded adapters to deliver exact FiO2 levels (e.g., 24%, 28%, 35%). Non-rebreather masks (NRB) are considered high-flow and can deliver up to 90-100% FiO2 by utilizing a reservoir bag and one-way valves to prevent re-breathing of exhaled air.

Priority Intervention: For patients with chronic obstructive pulmonary disease (COPD) who retain carbon dioxide, you must apply oxygen cautiously. High, uncontrolled oxygen can suppress their hypoxic drive to breathe. Start with low-flow oxygen (e.g., 2 L/min via nasal cannula) and monitor arterial blood gases (ABGs) closely.

Airway Management: Suctioning and Tracheostomy Care

When a patient cannot clear secretions, you must intervene. Suctioning techniques must balance necessity with risk. Key principles include:

• Use sterile technique for endotracheal or tracheostomy suctioning.
• Pre-oxygenate the patient with 100% oxygen before and after the procedure.
• Limit suctioning to 10-15 seconds at a time to prevent hypoxia.
• Apply suction only during catheter withdrawal, using a rotating motion.

Tracheostomy care involves maintaining a patent airway and preventing infection. Your priorities are securing the tube (checking tracheostomy tie tightness—you should be able to fit one finger underneath), cleaning the stoma site, and providing humidification (as the upper airway is bypassed). Always have a sterile trach tube of the same size and a smaller size, scissors, and hemostats at the bedside for emergency tube replacement. If a trach tube becomes dislodged in the first 72 hours post-op, do NOT attempt to reinsert it—call for help and ventilate via the stoma if needed, as the tract is not yet formed.

Chest Tube Management

Chest tubes re-establish negative pressure in the pleural space by draining air (pneumothorax), blood (hemothorax), or fluid (pleural effusion). The drainage system, typically a three-chamber system, must remain sealed and below the level of the patient's chest. The three chambers are:

1. Collection Chamber: Collects drainage. Measure output at the end of each shift.
2. Water-Seal Chamber: Acts as a one-way valve, allowing air to exit but not re-enter the pleural space. It should gently fluctuate (tidaling) with respiration and may bubble intermittently with a pneumothorax.
3. Suction Control Chamber: Regulates the amount of suction applied. This can be a water-filled (wet) chamber, where bubbling is continuous, or a dial (dry) chamber.

Critical Actions: Never clamp a chest tube routinely. If the drainage system breaks, momentarily submerge the end of the tube in sterile water to create a water seal until a new system is connected. Assess for signs of a new or worsening tension pneumothorax—a medical emergency characterized by severe respiratory distress, tracheal deviation away from the affected side, absent breath sounds, and hypotension.

Mechanical Ventilation and ABG Interpretation

Mechanical ventilation provides full or partial breathing support. You must understand common modes and your role in monitoring the patient and the machine. Key ventilator settings include FiO2, tidal volume, and modes like Assist-Control (AC) or Synchronized Intermittent Mandatory Ventilation (SIMV). Your nursing care focuses on preventing ventilator-associated pneumonia (VAP) through interventions like maintaining the head of bed at 30-45 degrees, providing daily oral care with chlorhexidine, and performing regular sedation vacations.

The ultimate measure of respiratory and metabolic status is the Arterial Blood Gas (ABG). You must be able to interpret values to identify acidosis/alkalosis, respiratory/metabolic origin, and compensation. Use the ROME method (Respiratory Opposite, Metabolic Equal) as a quick check:

• In Respiratory imbalances, pH and PaCO${}_2$ move in opposite directions.
• In Metabolic imbalances, pH and HCO${}_3^{-}$ move in the same direction.

*Scenario: A patient with COPD is admitted with increased shortness of breath. Their ABG results are: pH 7.32, PaCO${}_2$ 55 mm Hg, HCO${}_3^{-}$ 30 mmol/L.*

1. Acidosis or Alkalosis? pH 7.32 is < 7.35 = Acidosis.
2. Respiratory or Metabolic? Look at PaCO${}_2$ (respiratory driver). It is elevated (55). pH is low, PaCO${}_2$ is high → they move in opposite directions → Respiratory.
3. Compensated? HCO${}_3^{-}$ is also elevated (30). In acute respiratory acidosis, HCO${}_3^{-}$ should rise slightly. This elevated level indicates the kidneys have begun to compensate, making this a partially compensated respiratory acidosis.

Common Pitfalls

1. Confusing Hypoxia and Hypoxemia: Hypoxemia is a low oxygen level in the blood (low PaO${}_2$). Hypoxia is a low oxygen level at the tissue level. A patient can have hypoxemia leading to hypoxia, but hypoxia can also occur from other causes like anemia or poor perfusion. Treat the underlying cause.
2. Misinterpreting Chest Tube Bubbling: Continuous bubbling in the water-seal chamber indicates an air leak in the system (e.g., from the patient's pleural space or a connection). Continuous bubbling in the suction control chamber is expected when suction is applied. Assess the entire system to find the source.
3. Routine Tracheostomy Cuff Deflation: Do not deflate the cuff of a tracheostomy tube routinely without a specific order and a clear clinical reason (like assessing for speech). The cuff protects the lower airways from aspiration.
4. Over-reliance on Pulse Oximetry: Pulse oximetry (SpO${}_2$) measures peripheral oxygen saturation but can be falsely normal in conditions like carbon monoxide poisoning. It is also unreliable in cases of poor peripheral perfusion, hypothermia, or severe anemia. Always integrate SpO${}_2$ with your full clinical assessment.

Summary

• Your systematic respiratory assessment—inspection, auscultation, and vital sign analysis—is the cornerstone for identifying and prioritizing care.
• Select oxygen delivery systems based on the required FiO2 precision and the patient's condition, remembering the critical need for low-flow, controlled oxygen in patients with COPD.
• Airway management, including suctioning and tracheostomy care, requires strict aseptic technique, pre-oxygenation, and vigilance for complications like dislodgement or infection.
• Chest tube management hinges on maintaining a sealed, below-chest-level system, understanding normal chamber findings, and recognizing emergency situations like a tension pneumothorax.
• ABG interpretation using a systematic method (like ROME) allows you to pinpoint respiratory versus metabolic acid-base imbalances and the body's compensatory efforts, directly guiding your interventions.
• On the NCLEX, your first action in any respiratory distress scenario is always to ensure a patent airway and adequate ventilation before proceeding with further diagnostics or interventions.