K. Complete Evaluation and Treat Comorbid Conditions - Patients should be assessed for comorbid conditions. Conditions which can contribute to or be direct causes of COPD exacerbations include (adapted and modified from ERS guidelines): 

• Congestive heart failure
  
  
• Pneumonia
  
  
• Pulmonary embolism
  
  
• Spontaneous pneumothorax
  
  
• Inappropriate oxygen therapy
  
  
• Psychotropic drugs (hypnotics, tranquilizers, narcotics, etc.)
  
  
• Drug allergy (penicillin, cephalosporin, etc.)
  
  
• Metabolic disease (diabetes mellitus, electrolyte disorders such as hypophosphatemia, hypokalemia, etc.)
  
  
• Poor nutritional status
  
  
• Myopathy (e.g., steroid myopathy, etc.)
  
  
• Other acute illness (acute abdomen, GI hemorrhage, CVA, etc.)
  
  

1. History: Baseline respiratory status, sputum volume and characteristics, cough, duration and progression of symptoms, dyspnea severity, exercise limitations, sleep and eating difficulties, home care resources, home therapeutic regimen, symptoms of comorbid acute and chronic conditions

2. Clinical assessment: Temperature, respiratory rate, heart rate, cyanosis, accessory muscle use, edema, cor pulmonale, bronchospasm, hemodynamic instability, altered mentation, paradoxical abdominal retractions, use of accessory respiratory muscles, pneumonia

3. Spirometry (optional): Peak expiratory flow rate, FEV₁.

4. Laboratory: ABG, chest radiograph, EKG, theophylline level (if applicable), WBC count, blood cultures if pneumonia, electrolytes, BUN, glucose.

L. Does Patient Need Mechanical Ventilation? - Decision to initiate mechanical ventilation and endotracheal intubation can be made prior to obtaining arterial blood gases. Advance directives should be considered prior to initiating these supportive measures.

Indications for mechanical ventilation (invasive or noninvasive) include:
 
• Severe respiratory or combined respiratory and metabolic acidosis
• Sustained respiratory rate greater than 40 per minute
• Abnormal breathing pattern suggestive of increased respiratory workload and/or respiratory muscle fatigue
• Depressed mental status
• Severe hypoxemia
  
  
Indications for tracheal intubation include:
 
• Suspected airway obstruction
• Depressed mental status
• High risk of gastropulmonary reflux and aspiration
• Difficulty managing secretions.

M. Ventilate and Perform CPR as Indicated - CPR should be performed according to Advanced Cardiac Life Support (ACLS) protocol. A physician with special expertise in critical care medicine should be consulted at this point. Care should be used to avoid complications of auto PEEP and acute respiratory alkalosis.

N. Does Patient Meet ICU Criteria? - Any of the following that would prompt admission to the ICU for closer observation and monitoring include (adapted and modified from American Thoracic Society guidelines): 

• Severe dyspnea that responds inadequately to initial emergency-room therapy
• Confusion, lethargy, or respiratory muscle fatigue
• Persistent or worsening hypoxemia despite supplemental O₂ or severe or worsening respiratory acidosis (pH < 7.30)
• Required assisted mechanical ventilation, whether through tracheal intubation or noninvasive techniques

O. Admit to ICU - Patients admitted to ICU receive the same treatment as those admitted to the ward, but with addition of cardiopulmonary monitoring and direct observation. A specialist in critical care medicine should be consulted for these patients.

P. Is Patient Improving? -  Improvement is indicated by reduced dyspnea, decreased respiratory rate, improved air movement, and decreased use of accessory muscles. Objective measures including peak expiratory flow, FEV₁ and/or ABGs should demonstrate improvement.

Q. Intensify Treatment 

• Consider using aerosol B-agonists if MDI cannot be used effectively.
• Consider using IV steroids and/or antibiotics.
• Titrate oxygen, using Oxygen Therapy Module B4.
• Consider comorbidities or other contributory causes of COPD and treat.

• Features for the severe exacerbation are resolved (see Annotation F above).
• Anticipated need for inhaled bronchodilators is no more frequent than every 4 hours and patient is on oral medications.
• Reversible component of airway obstruction, if present, is under stable control.
• Patient or caregiver understands appropriate use of medications.
• Follow-up and home care arrangements have been completed (e.g., visiting nurse, oxygen delivery, meal provisions).
• Patient, family, and physicians are confident that the patient can manage successfully.

T. Modify Current Treatment - If the patient is improving, consider: 

• Decreasing frequency of inhaled B-agonists to every 4 to 6 hours
• Switching to MDI with spacers
• Switching from parenteral to oral medication
• Titrating oxygen as per oxygen protocol