Tocolytic-Induced Pulmonary Edema
Epidemiology
- Beta agonists (ritodrine, terbutaline, albuterol) are used to inhibit uterine contractions and preterm labor
- Incidence: 0.5-5% of treated cases
- Risk Factors
- Use of Cortisosteroids
- Twin Gestation
- Fluid Overload (particularly with saline)
- Anemia
Physiology
- Possible Mechanisms
- Prolonged exposure to catecholamines: increase maternal heart rate and cardiac output, as wella s cause peripheral vasodilation
- Increased capillary permeability
- Large volume of IVF administered in response to maternal tachycardia
- Glucocorticoids administered in preterm labor can also contribute to fluid retention
- Autotransfusion: due to uterine contraction during labor
Diagnosis
- CBC: anemia
- Albumin: decreased
- Swan: PCWP may be normal-elevated
- Echo: normal LV function (has been reported in cases with elevated PCWP)
Clinical Presentations
- Hypotension (see [[Hypotension]]): may occur
- Acute Lung Injury-ARDS (see [[Acute Lung Injury-ARDS]]): may occur in the post-partum period
Treatment
- Oxygen
- Supportive care
- Discontinue beta agonists -> pulmonary edema usually resolves rapidly
- Restart of beta agonists has been considered -> this may resume the peripheral vasodilation
- Avoidance of corticosteroids
References