Management of critical asthma syndrome during pregnancy

Abstract

One-third of pregnant asthmatics experience a worsening of their asthma that may progress to a critical asthma syndrome (CAS) that includes status asthmaticus (SA) and near-fatal asthma (NFA). Patients with severe asthma before pregnancy may experience more exacerbations, especially during late pregnancy. Prevention of the CAS includes excellent asthma control involving targeted early and regular medical care of the pregnant asthmatic, together with medication compliance. Spontaneous abortion risk is higher in pregnant women with uncontrolled asthma than in non-asthmatics. Should CAS occur during pregnancy, aggressive bronchodilator therapy, montelukast, and systemic corticosteroids can be used in the context of respiratory monitoring, preferably in an Intensive Care Unit (ICU). Systemic epinephrine should be avoided due to potential teratogenic side-effects and placental/uterine vasoconstriction. Non-invasive ventilation has been used in some cases. Intratracheal intubation can be hazardous and rapid-sequence intubation by an experienced physician is recommended. Mechanical ventilation parameters are adjusted based on changes to respiratory mechanics in the pregnant patient. An inhaled helium-oxygen gas admixture may promote laminar airflow and improve gas exchange. Permissive hypercapnea is controversial, but may be unavoidable. Sedation with propofol which itself has bronchodilating properties is preferred to benzodiazepines. Case reports delineating good outcomes for both mother and fetus despite intubation for SA suggest that multidisciplinary ICU care of the pregnant asthmatic with critical asthma are feasible especially if hypoxemia is avoided.