History of Present Illness: Shortness of Breath with Hypoxemia
Chief Complaint
Patient presents with acute shortness of breath and documented hypoxemia (SpO2 <92%).
Onset and Timing
- Acute onset (within hours to days) versus subacute/chronic progression (weeks to months) 1
- Time of symptom onset and progression pattern
- Precipitating factors or triggers identified by patient 1
Severity Assessment
- Current oxygen saturation on room air and response to supplemental oxygen 2
- Respiratory rate at presentation (critical vital sign indicator) 1
- Presence of respiratory distress signs: increased work of breathing, use of accessory muscles, inability to speak in full sentences 3
- Stridor or obstructed breathing pattern (indicates potential airway compromise) 1
- Level of consciousness and agitation (may indicate severe hypoxemia or impending respiratory failure) 1
Associated Symptoms
Cardiac-Related
- Chest pain or pressure (consider acute coronary syndrome) 1
- Facial or peripheral edema (suggests heart failure or other systemic process) 1
- Orthopnea or paroxysmal nocturnal dyspnea 1
- Palpitations or syncope 1
Pulmonary-Related
- Cough (productive versus non-productive, sputum characteristics) 3
- Wheezing (suggests bronchospasm from asthma or COPD) 3
- Hemoptysis 3
- Pleuritic chest pain 3
Systemic Signs
- Fever or chills (suggests infectious etiology including sepsis) 3
- Confusion or altered mental status 3
- Cyanosis (though unreliable, especially in darker skin tones) 3
Risk Factors for Hypercapnic Respiratory Failure
Critical to identify as these patients require different oxygen targets (88-92% versus 94-98%) 2:
- Known COPD or fixed airflow obstruction 3, 2
- Cystic fibrosis 2
- Neuromuscular disease affecting respiratory muscles 2
- Chest wall deformities or morbid obesity 2
Past Medical History
- COPD, asthma, or other chronic lung disease (determines oxygen titration strategy) 3, 2
- Heart failure with preserved or reduced ejection fraction 1
- Prior episodes of respiratory failure or intubation 4
- Recent trauma or surgery 5
- Malignancy (especially advanced cancer, which may benefit from oxygen therapy) 3
- History of pulmonary embolism or deep vein thrombosis 4
- Immunosuppression or chronic infections 3
Medications
- Current bronchodilator use (albuterol, ipratropium) and frequency 6, 7
- Home oxygen therapy (flow rate and duration) 2
- Recent changes in medications 6
- Anticoagulation status 1
Social and Environmental History
- Smoking history (pack-years) 3
- Occupational or environmental exposures 3
- Recent travel or sick contacts 3
- Diving history (decompression injury benefits from oxygen) 3