What is the preferred medication, inhaled corticosteroid (ICS) or bronchodilator, to administer to a patient with asthma approximately one hour prior to a procedure?

Bronchodilator Administration is Recommended Before Procedures for Patients with Asthma

For patients with asthma, a bronchodilator should be administered approximately one hour before a procedure rather than an inhaled corticosteroid to prevent procedure-related bronchospasm. 1

Rationale for Bronchodilator Use Before Procedures

• Bronchospasm during procedures such as bronchoscopy is a recognized risk in asthmatic patients, with studies showing that up to 8% of asthmatic patients may develop laryngospasm or bronchospasm during bronchoscopy 1
• Premedication with a bronchodilator has been shown to prevent the fall in postoperative FEV1 in patients with asthma undergoing procedures 1
• The British Thoracic Society specifically recommends that "asthmatic subjects should be premedicated with a bronchodilator before bronchoscopy" with a Grade B recommendation 1

Specific Bronchodilator Recommendations

• Short-acting β2-agonists (SABAs) such as albuterol are the preferred bronchodilators for pre-procedure use 1:

  • They provide rapid, dose-dependent bronchodilation with minimal side effects 1
  • Should be administered 15-20 minutes before the procedure 1
  • Effective for 2-4 hours in protecting against or attenuating bronchospasm 1

• For patients with asthma undergoing surgery or invasive procedures:

  • Reviewing the level of asthma control, medication use, and pulmonary function before the procedure is essential 1
  • Providing medications before surgery to improve lung function is recommended if lung function is not well controlled 1

Role of Inhaled Corticosteroids

• While inhaled corticosteroids (ICS) are the preferred long-term control medication for asthma, they are not the recommended choice for immediate pre-procedure bronchospasm prevention 1
• ICS have a delayed onset of action (hours to days) and primarily address the underlying inflammation rather than providing immediate bronchodilation 1
• For patients already on ICS therapy, they should continue their regular dosing but still receive a pre-procedure bronchodilator 1

Special Considerations

• For patients with severe asthma or poor control, consider:

  • Ensuring the patient continues their regular controller medications 1
  • Potentially adding a short course of oral corticosteroids if lung function is not well controlled before the procedure 1
  • Using continuous oxygen monitoring during the procedure 1

• For patients with COPD in addition to asthma:

  • Check spirometric parameters before the procedure 1
  • If COPD is severe (FEV1 <40% predicted and/or SaO2 <93%), arterial blood gas tensions should also be measured 1
  • Use oxygen supplementation and sedation with extreme caution if pre-procedure arterial CO2 is elevated 1

Common Pitfalls to Avoid

• Failing to administer the bronchodilator at the optimal time (15-20 minutes before the procedure) 1
• Relying solely on inhaled corticosteroids for immediate pre-procedure bronchospasm prevention 1
• Overlooking the need for additional monitoring in patients with severe asthma 1
• Not considering the potential for lignocaine (lidocaine) to produce bronchoconstriction in some asthmatic patients during procedures 1

By following these evidence-based recommendations, clinicians can minimize the risk of procedure-related bronchospasm and improve outcomes for patients with asthma.