Atrial Septal Defect (ASD) 

 

 

Considerations

 

  • Etiology & severity of ASD: Size, shunt (LR / RL)

  • Complications of chronic L to R shunt:

    • Arrhythmias (atrial fibrillation & supraventricular tachycardias)

    • Pulmonary HTN, RV dysfunction, shunt reversal (RL with hypoxemia)

    • Tricuspid valve & pulmonic valve disease  

  • ↑ perioperative risk of:

    • Arrhythmia, pulmonary hypertension crisis, RV dysfunction/failure

    • RL shunt reversal: hypoxemia, paradoxical air embolism 

    • Paradoxical embolism (air, CO2, septic, thrombus)

  • Comorbid disease:

    • Adult congenital heart disease, Down syndrome, etc

    • Previous closures

  • Medications: anticoagulation, antiarrhythmics

  • Considerations for closure of ASD:

    • Out of OR considerations

    • Complications (tamponade, arrhythmias, valve disruption, & emboli)

 

 

Goals

 

  • Hemodynamic goals:

    • Preload: maintain adequate preload 

    • Rate: maintain normal rate 

    • Rhythm: maintain normal sinus rhythm 

    • Contractility: maintain adequate contractility 

    • Afterload: avoid extremes of systemic vascular resistance;  ↑ SVR may precipitate pulmonary hypertension & RV dysfunction, ↓ SVR may cause RL shunting & hypoxemia

  • De-air lines (risk of pulmonary air embolism) 

 

 

Pregnancy Considerations 

 

  • Pregnancy is well-tolerated if pulmonary hypertension not present 

  • Control of SVR critical to limiting bidirectional shunting

  • Labour: early titrated epidural preferred

  • For epidural, do NOT use loss of resistance to air (use saline)

  • C-section: give anesthetic by titrated epidural