Bronchospasm represents one of anesthesia’s most serious complications. The article notes that “7% of all anesthesia-related deaths in France are attributed to bronchospasm.” Asthmatic patients face particular risk, with 9% experiencing this condition during general anesthesia. Respiratory events including bronchospasm accounted for 28% of claims involving anesthesia-related brain damage or death, resulting in the highest mean cost per closed claim.
This condition involves sudden constriction of bronchial smooth muscle causing airway narrowing, increased breathing effort, decreased airflow, air trapping, and ventilation-perfusion mismatch. It can elevate pulmonary vascular resistance, leading to right ventricular strain. The condition falls into two categories: allergic (IgE-mediated, presenting with skin symptoms and prolonged desaturation) and non-allergic (typically following airway intubation, lacking cutaneous manifestations).
Preoperative management requires delaying elective surgery if patients present with wheezing, cough, or dyspnea. Pulmonology consultation suits patients with suspected asthma. Those with peak flow or FEV1 below 80% of normal may benefit from oral steroids. Smoking cessation two months before surgery significantly reduces risk. Frequent exacerbations, hospitalizations, and previous intubation increase risk. Recent respiratory infections warrant screening, though debate continues regarding their significance.
Recognition represents the critical first step in treatment. Bronchospasm typically manifests as “wheezing, high peak pressures on the ventilator, and prolonged expiratory times.” Capnography shows “a saw tooth or a shark fin with a gradual slope.” Differential diagnoses include kinked endotracheal tubes, mucus plugging, pulmonary embolism, pulmonary edema, or bronchial intubation.
Immediate response requires increasing FiO2 to 100%, stopping surgical stimulation, and calling for assistance. Bag-mask ventilation allows direct compliance assessment and faster inspiratory rates. Volatile anesthetics relax bronchial smooth muscle; isoflurane and sevoflurane prove particularly useful, while desflurane should be avoided due to airway irritation. Propofol offers direct bronchodilatory effects in total intravenous anesthesia cases.
If initial measures fail, rapid-acting beta-2-selective agonists via nebulizer or metered-dose inhaler become necessary. Inhalers require larger doses (8-10 puffs) due to endotracheal tube deposition. High-dose corticosteroids may help refractory cases, though onset requires 4-6 hours. Severe, unresponsive bronchospasm may require intravenous epinephrine pushes or continuous infusion. Magnesium sulfate assists difficult cases but risks muscle weakness and CNS depression. Nitroglycerin has shown anecdotal benefit through direct smooth muscle relaxation.
Persistent acute bronchospasm at case conclusion may necessitate postoperative mechanical ventilation. Short-acting beta-2 agonist readministration before emergence is warranted. Neostigmine for neuromuscular blockade reversal increases bronchospasm risk through muscarinic and pro-secretory effects; glycopyrrolate co-administration counteracts this.
The article emphasizes that “bronchospasm is a serious complication of everyday anesthetic practice and can result in significant morbidity and mortality.” Proper documentation ensures future providers can adequately prepare, as patients experiencing one episode face increased likelihood of subsequent episodes.