Anaesthesia management of patients with airway susceptibilities: what have we learnt from animal models?

Anaesthesia management of patients with airway susceptibility remains a challenge in daily clinical practice due to the increased risk of perioperative bronchospasm. Therefore, understanding the mechanisms participating in the interaction between anaesthetic drugs and the lungs is essential in providing the optimal care for patients with chronic lung diseases. Experimental studies performed on various animal models mimicking airway susceptibility have played a key role in understanding the pathogenesis of lung diseases and have characterised the different pathways involved in the altered airway and lung tissue responses to anaesthetic agents. This narrative review highlights the progress that has been achieved by investigations in animal models and discusses the potential translation of these experimental findings to the clinical setting. The application of animal models with normal and allergically sensitised airways demonstrated that volatile and intravenous anaesthetic agents, muscle relaxants, analgesics and local anaesthetics exert their pulmonary effects via different neurosensorial pathways and through activating various receptors in the lungs. Attention is drawn to the significant differences in the pulmonary effects of anaesthetic agents between lungs with normal and those with susceptible airways. Extrapolating clear-cut conclusions from animal research to clinical practices should be made with caution, particularly for muscle relaxants, opioids and local anaesthetics wherein complex pathophysiological mechanisms are responsible for the potential respiratory effects of these agents. Animal models are of great importance in evaluating the potential interaction between anaesthetic drugs and the lungs, in identifying the pathways involved and in targeting preventive or treatment strategies to the lung compartment primarily involved.