Cardinal Symptoms and Red Flag Findings: Difficulty breathing, respiratory distress, SpO₂ <92%, confusion, restlessness, hyperventilation, hypoventilation, cyanosis, clubbing of nailbeds, adventitious lung sounds (e.g., wheezes, rales, rhonchi, stridor).

History: Cough (productive or nonproductive), dyspnea, hemoptysis, CP, swelling of lower extremities, energy level, sleep pattern, COPD (asthma, chronic bronchitis, emphysema), TB, pneumonia, URI, environmental allergies.

Ease of Breathing: Ask Pt about breathing; use Pt’s subjective terminology when documenting (e.g., “feels like I can’t catch my breath”). For shortness of breath (SOB), ask if it’s triggered by activity and if it’s relieved with rest. Ask about energy levels and if Pt can eat and talk comfortably.

Respiratory Rate: Normal rate is 12 to 20; Rates >20/min should be investigated. Rates >26/min can be critical unless it’s normal baseline for Pt.

Medication: Bronchodilators, acetylcysteine, aminophylline, theophylline, anticholinergics, corticosteroids.

Respirations: Rate, depth, effort, pattern.

Inspect: Signs of distress and/or use of accessory muscles (nasal flaring or sternal retractions), both indicate respiratory distress but can also be baseline in presence of chronic disease (e.g., emphysema); Size and shape of chest, symmetry of chest wall movement, and use of accessory muscles; Lower extremities for edema and nailbeds for cyanosis and clubbing indicating chronic hypoxia; Trachea for scars, stomas, or deviation from midline.

Palpate: Anterior and posterior thorax for subcutaneous emphysema, crepitus, and tenderness; assess tactile fremitus; palpate chest as Pt says, “99.”

Percuss: Anterior and posterior thorax for tympany (hollow organs), resonance (air-filled organs), dullness (solid organs), or flatness (muscle or bone).

Auscultate: Instruct Pt to breathe deeply with mouth open. Listen to all anterior and posterior lung fields noting normal, abnormal, diminished or absence of lung sounds. Order of auscultation: begin at the top, near the shoulders, and work toward the bottom, near the diaphragm, moving from left to right working in a zigzag pattern.

Use of Oxygen: Note amount of O₂ ordered and method of delivery. Is Pt using O₂ all the time or just during activity, and is device correctly applied?

Pulse Oximetry (SpO₂): 97% to 99% is normal, although 93% to 97% may be normal for some Pts. Always look at the whole picture, not just a single reading. Also, pulse oximetry can be inaccurate in the presence of peripheral vascular disease.

ABG Results: ABG analysis allows for assessment of acid-base balance and oxygenation. It also tells how well the lungs and kidneys are compensating or responding to treatments. pH, PaCO₂, and HCO₃ determine acid-base balance; PaO₂ and SpO₂ indicate oxygenation status.

Normal Arterial Blood Gas Values

Arterial Blood Gas Normal Interpretation Guide

Interpretation Guide

^* A = acid; B = base (alkaline); N = normal.

• Enter patient values for pH, CO₂, and HCO₃.
• Enter N, A, or B in third column of each to reflect whether value is normal, acidic, or alkaline (base).
• Determine which matches pH.
• Whichever matches pH is source of problem. Write metabolic or respiratory.
• If pH is below normal, write in acidosis; if it is above normal, write in alkalosis.
• Refer to Respiratory tab for more instruction.

Subtopic(s)

• Respiratory Patterns
• Auscultation of Lung Sounds