Anaesthetic management in asthma

Abstract

Anaesthetic management in asthmatic patients has been focused on avoiding bronchoconstriction and inducing bronchodilation. However, the definition of asthma has changed over the past decade. Asthma has been defined as a clinical syndrome characterized by an inflammatory process that extends beyond the central airways to the distal airways and lung parenchyma. With this concept in mind, and knowing that asthma is a common disorder with increasing prevalence rates and severity worldwide, a rational choice of anaesthetic agents and procedures is mandatory. Thus, we pursued an update on the pharmacologic and technical anaesthetic approach for the asthmatic patient. When feasible, regional anaesthesia should be preferred because it reduces airway irritation and postoperative complications. If general anaesthesia is unavoidable, a laryngeal mask airway is safer than endotracheal intubation. Lidocaine inhalation, alone or combined with albuterol, minimizes histamine-induced bronchoconstriction. Propofol and ketamine inhibit bronchoconstriction, decreasing the risk of bronchospasm during anaesthesia induction. Propofol yields central airway dilation and is more reliable than etomidate or thiopental. Halothane, enflurane, and isoflurane are potent bronchodilators and can be helpful even in status asthmaticus. Sevoflurane has shown controversial results in asthmatic patients. Vecuronium, rocuronium, cisatracurium, and pancuronium do not induce bronchospasm, while atracurium and mivacurium can dose-dependently release histamine and should be cautiously administered in those patients. Further knowledge about the sites of action of anaesthetic agents in the lung, allied with our understanding of asthma pathophysiology, will establish the best anaesthetic approach for people with asthma.