Increase in cough, sputum, or dyspnea beyond the normal day-to-day variation
Hypoxemia
Tachypnea
Tachycardia
Hypertension
Cyanosis
Altered mental status
Hypercapnia
Accessory respiratory muscle use
Pursed-lip exhalation
COPD exacerbation
Pulmonary
Acute asthma exacerbation
Airway obstruction
Acute asthma exacerbation 
Anaphylaxis
Aspiration pneumonia and pneumonitis
Angioedema