How should I manage a patient with Tachycardia-Brady (Tachycardia-Bradycardia) syndrome in active labor?

Management of Tachycardia-Bradycardia Syndrome During Active Labor

For a patient with tachycardia-bradycardia syndrome in active labor, continuous cardiac monitoring with immediate availability of temporary pacing and defibrillation equipment is essential, along with treatment of symptomatic episodes according to hemodynamic stability.

Initial Assessment and Monitoring

• Establish continuous electrocardiographic monitoring and peripheral pulse monitoring 1
• Monitor maternal hemodynamic status closely with consideration for invasive monitoring if patient is unstable
• Position patient in left lateral decubitus position to prevent supine hypotensive syndrome 1
• Have temporary pacing and defibrillation equipment immediately available 1

Management of Bradycardia Episodes

For symptomatic bradycardia (signs of hemodynamic instability, altered mental status, chest pain, dyspnea):

1. First-line treatment:

   • Atropine 0.5 mg IV (can repeat up to 3 mg total) 1, 2
   • Change maternal position to left lateral decubitus if supine 1

2. If bradycardia persists:

   • Consider IV infusion of β-adrenergic agonists (dopamine, epinephrine) 1
   • Transcutaneous pacing for persistent symptomatic bradycardia 1, 2
   • Prepare for possible transvenous temporary pacing if bradycardia is refractory 1

Management of Tachycardia Episodes

For symptomatic tachycardia:

1. Hemodynamically stable patient:

   • Vagal maneuvers as first step 1
   • IV adenosine can be safely used in all trimesters including labor 3

2. Hemodynamically unstable patient:

   • Immediate electrical cardioversion (with prior sedation if conscious) 1
   • In select cases of regular narrow-complex tachycardia with unstable signs, a trial of adenosine before cardioversion may be considered 1

Labor and Delivery Considerations

• Spontaneous vaginal delivery is preferred if cardiac condition is stable 1
• Avoid prolonged bearing down efforts during second stage of labor 1
• Consider assisted vaginal delivery (low forceps or vacuum) to shorten second stage 1
• Epidural analgesia is preferred as it stabilizes cardiac output 1
• For Caesarean section (if indicated), continuous spinal or combined spinal-epidural anesthesia is recommended 1
• Active management of third stage with a single dose of intramuscular oxytocin; avoid ergometrine 1
• Monitor for auto-transfusion effect after delivery (increased preload) 1

Special Considerations

• Permanent pacemaker presence does not contraindicate pregnancy 1
• If patient has an implantable cardioverter-defibrillator (ICD), consider suspending tachyarrhythmia functions during labor to prevent inappropriate shocks 1
• For patients with pacemakers, ensure bipolar electrocautery system is used if cesarean delivery is required 1

Post-Delivery Management

• Continue cardiac monitoring in the immediate postpartum period
• Resume or adjust antiarrhythmic medications as needed
• If anticoagulation was used, restart in consultation with obstetrician after post-partum bleeding has stopped 1

Pitfalls and Caveats

• Avoid magnesium sulfate if possible as it may worsen bradycardia
• Be aware that physiologic changes of pregnancy (increased heart rate, cardiac output) may mask or exacerbate underlying arrhythmias
• Remember that hemodynamic changes during labor contractions and immediate postpartum period (auto-transfusion) may trigger arrhythmias
• Ensure coordination between cardiology, obstetrics, and anesthesiology teams for optimal management

This approach prioritizes maternal cardiovascular stability while ensuring fetal wellbeing during the challenging period of active labor in a patient with tachycardia-bradycardia syndrome.