Can tocolytics be given to delay delivery in a patient in preterm labor at a facility without obstetric (OB) resources to facilitate transfer to an appropriate facility?

Tocolytic Use for Delaying Delivery in Facilities Without OB Resources

Tocolytics can be given to delay delivery for 48-72 hours in preterm labor to facilitate maternal transfer to a facility with appropriate obstetric resources, particularly when this allows for administration of antenatal corticosteroids and improves neonatal outcomes. 1

Rationale for Tocolytic Use During Transfer

The primary goal of tocolytic therapy in this scenario is not to stop preterm labor completely but to:

1. Delay delivery long enough for safe maternal transfer
2. Allow time for administration of interventions that improve neonatal outcomes
3. Ensure delivery occurs in a facility with appropriate maternal and neonatal care capabilities

According to ACOG/SMFM guidelines, hospitals without optimal resources for maternal and neonatal care should have protocols in place to facilitate timely transport to appropriate facilities. These protocols should include recommendations for tocolytic therapy to enable safe transfer 1.

Appropriate Clinical Scenario

Tocolytic therapy for transfer is most appropriate when:

• Patient is in preterm labor at a facility without adequate obstetric resources
• Gestational age is between 23-34 weeks (particularly beneficial <32 weeks)
• There are no contraindications to tocolysis
• The goal is to gain 48-72 hours for maternal transfer and steroid administration
• The receiving facility has appropriate maternal-fetal and neonatal care capabilities

Choice of Tocolytic Agent

While several tocolytic options exist, the evidence suggests:

• Nifedipine may be a reasonable first choice due to ease of administration and limited side effects compared to beta-mimetics 2
• Indomethacin may be considered for acute tocolysis at gestational ages <32 weeks, but should be limited to <48 hours of use 2
• Magnesium sulfate has a controversial role as a tocolytic but provides the additional benefit of fetal neuroprotection when delivery is anticipated 1, 3

Important Considerations and Precautions

• Tocolytics typically delay delivery for only 48-72 hours, which is sufficient for transfer and steroid administration but not for long-term pregnancy prolongation 2, 4
• Maternal safety must be prioritized - certain tocolytics carry significant risks of maternal cardiovascular and respiratory effects 5
• The risk-benefit ratio must be continuously reassessed during tocolytic administration 6
• Contraindications to tocolysis must be identified (e.g., severe preeclampsia, placental abruption, intrauterine infection)

Protocol for Implementation

1. Assess appropriateness for tocolysis:

   • Confirm preterm labor diagnosis
   • Evaluate for contraindications to tocolysis
   • Determine if maternal and fetal status permit safe transfer

2. Initiate tocolytic therapy:

   • Choose agent based on gestational age, maternal comorbidities, and availability
   • Begin at appropriate dosing for the selected agent

3. Arrange transfer:

   • Contact receiving facility with appropriate level of maternal and neonatal care
   • Coordinate with transport team regarding timing and monitoring during transfer

4. Concurrent interventions:

   • Administer antenatal corticosteroids if 23-34 weeks gestation
   • Consider magnesium sulfate for neuroprotection if <32 weeks
   • Initiate appropriate antibiotics if indicated (e.g., for GBS prophylaxis)

Pitfalls and Caveats

• Do not delay transfer for administration of tocolytics if rapid deterioration of maternal or fetal status is occurring
• Avoid prolonged tocolytic use beyond what is needed for transfer and steroid administration
• Monitor closely for adverse effects of tocolytic agents, particularly cardiovascular and pulmonary complications
• Recognize that tocolysis may be contraindicated in certain conditions like chorioamnionitis, severe preeclampsia, or significant hemorrhage

The evidence supports that while tocolytics may not significantly improve long-term neonatal outcomes by themselves, they can delay delivery long enough to allow for interventions that do improve outcomes, particularly antenatal corticosteroids and transfer to facilities with appropriate neonatal intensive care 4.