Bronchospasm

Learning objectives

Bronchospasm or a bronchial spasm is a sudden constriction of the muscles in the walls of the bronchioles
It is caused by the release (degranulation) of substances from mast cells or basophils under the influence of anaphylatoxins

Bronchospasm is a reversible reflex spasm of the smooth muscle in the bronchi and is vagally mediated and is more common in asthmatics
Histamine, released due to stimuli such as cold air, smoking, upper respiratory tract infection, or inhaled irritants, provokes bronchospasm
Bronchospasm during the perioperative period may be caused by anaphylaxis, tracheal intubation, drugs (i.e., morphine or atracurium)

Perform a thorough assessment of the patient before surgery
Careful medication history should be taken with particular reference to drug sensitivities
Encourage the patient to stop smoking preoperatively
Wheezing, cough increased sputum production, shortness of breath and diurnal variability in peak expiratory flow rate (PEFR) indicate poor control
Recent or frequent exacerbations or admission to the hospital may be an indication to postpone non-essential surgery

The risk of bronchospasm is reduced by:

Pretreatment with an inhaled/nebulized beta-agonist, 30 minutes prior to surgery
Induction of anesthesia with propofol
An adequate depth of anesthesia before airway instrumentation