What is the optimal time to administer salbutamol (albuterol) prior to a surgical operation in an asthma patient?

Optimal Timing of Salbutamol Administration Prior to Surgery in Asthma Patients

Salbutamol (albuterol) should be administered 30 minutes before induction of anesthesia in asthma patients undergoing surgery to optimize bronchodilation and reduce perioperative respiratory complications. 1

Rationale and Evidence

• Nebulized salbutamol administered 30 minutes before anesthesia induction reduces perioperative respiratory complications (cough, bronchospasm, laryngospasm) by approximately 50% in patients with respiratory issues 2
• The American Society of Anesthesiologists recommends this timing to achieve optimal bronchodilation while minimizing potential side effects 1
• Prospective studies demonstrate that preoperative salbutamol nebulization significantly decreases the incidence of perioperative respiratory adverse events compared to no nebulization 2

Dosing Recommendations

• For adults: 5 mg nebulized salbutamol 30 minutes before induction 2
• For children weighing less than 20 kg: 2.5 mg nebulized salbutamol 1
• For children weighing more than 20 kg: 5 mg nebulized salbutamol 1
• Alternative delivery method: Multiple actuations of metered-dose inhaler (MDI) into a large spacer device (2 puffs 10-20 times) if nebulization is unavailable 2

Clinical Considerations

• Salbutamol administration is particularly important in patients with:

  • Active asthma symptoms 2
  • Recent upper respiratory infection (especially in children under 6 years) 2
  • History of bronchial hyperreactivity 2

• Inhalation route is superior to oral administration for achieving rapid bronchodilation with fewer systemic side effects 3

Monitoring After Administration

• Assess response to treatment by measuring peak expiratory flow (PEF) or forced expiratory volume in 1 second (FEV1) 15-30 minutes after administration 2
• Target response: PEF >75% of predicted or personal best 2
• If inadequate response (PEF <50% predicted), consider additional bronchodilator treatment before proceeding 2

Potential Adverse Effects to Monitor

• Tachycardia (heart rate >110 beats/min) 2
• Tremor 4
• Hypokalemia (particularly with higher doses) 5, 4
• Headache, palpitations, and anxiety (more common with higher doses) 4

Special Situations

• For patients with severe asthma or recent exacerbation, consider adding ipratropium 0.5 mg to the nebulized salbutamol for enhanced bronchodilation 2
• In patients already taking oral theophyllines, monitor for potential additive side effects when administering salbutamol 6

Common Pitfalls to Avoid

• Underestimating asthma severity before surgery - always perform objective assessment 2
• Inadequate preoperative bronchodilation - ensure sufficient time (30 minutes) between administration and induction 2
• Failure to monitor response to treatment - always reassess respiratory status before proceeding with anesthesia 2
• Using excessive doses - higher doses (>5 mg) may increase side effects without significantly improving bronchodilation 4