What is the management of fetal hydrops?

Management of Fetal Hydrops

The cornerstone of managing fetal hydrops is a thorough evaluation for the underlying etiology, with treatment decisions based on whether there is a treatable cause and the gestational age at which hydrops develops or is first identified. 1

Initial Evaluation

1. Antibody screen (indirect Coombs test) to verify nonimmune hydrops
2. Detailed sonography with echocardiography to evaluate fetal and placental abnormalities
3. Middle cerebral artery Doppler evaluation for anemia
4. Fetal karyotype or chromosomal microarray analysis regardless of whether structural anomalies are identified

Management Algorithm

Step 1: Determine Underlying Etiology

Hydrops cases generally fall into three categories:

• Treatable causes requiring urgent intervention
• Lethal conditions where pregnancy termination or comfort care are appropriate
• Idiopathic cases with uncertain but likely poor prognosis

Step 2: Treatment Based on Etiology

Treatable Causes:

• Cardiac tachyarrhythmias (SVT, atrial flutter): Maternal transplacental antiarrhythmic medications 1
• Fetal anemia (parvovirus, fetomaternal hemorrhage): Intrauterine transfusion 1, 2
• Pleural effusions/hydrothorax: Fetal needle drainage or thoracoamniotic shunt 1
• Congenital pulmonary airway malformation (CPAM):
  • Macrocystic: Drainage or thoracoamniotic shunt
  • Microcystic: Maternal corticosteroids (betamethasone 12.5 mg IM q24h × 2 or dexamethasone 6.25 mg IM q12h × 4) 1
• Twin complications:
  • Twin-twin transfusion syndrome (TTTS): Laser ablation of placental anastomoses
  • Twin-reversed arterial perfusion: Radiofrequency ablation 1

Non-treatable/Lethal Causes:

• Offer pregnancy termination if identified prior to viability 1
• For continuing pregnancies, provide palliative/comfort care

Idiopathic Cases:

• Consider corticosteroids and antepartum surveillance
• Deliver at a center capable of stabilizing and treating critically ill neonates 1

Step 3: Maternal Monitoring

• Monitor for development of maternal complications, particularly mirror syndrome
• Serial evaluation of maternal blood pressure and edema 1, 3
• Approximately 50% of cases with fetal hydrops develop serious maternal complications 3

Step 4: Delivery Planning

• Timing: Avoid preterm delivery except for obstetric indications 1
• Indications for delivery:
  • Development of mirror syndrome (severe preeclampsia-like condition) 1
  • Standard obstetric indications
• Location: Tertiary care center with capability to stabilize and treat critically ill neonates 1

Prognosis

• Overall survival from diagnosis is approximately 27%, increasing to 55% if born alive 4
• Prognosis depends on:
  • Underlying etiology (aneuploidy confers poor prognosis)
  • Response to therapy if treatable
  • Gestational age at detection and delivery 1
• Even in the absence of aneuploidy, neonatal survival is often <50% 1

Pitfalls and Caveats

1. Mirror syndrome can develop rapidly and necessitates delivery in most cases 1
2. Fetal bradyarrhythmias (heart block) have poor response to treatment and generally poor prognosis 1
3. Antenatal diagnosis is critical - thorough evaluation can identify causes in nearly 60% of cases prenatally and 85% when postnatal detection is included 1
4. Long-term neurological outcomes may be affected even after successful treatment of conditions like parvovirus-induced hydrops 1
5. Maternal complications are common and require careful monitoring throughout pregnancy 3

Sonographic evaluation plays a major role in determining optimal perinatal management and can contribute to reducing mortality and morbidity associated with hydrops fetalis 5.