How do you manage refractory contractions in a pregnant or postpartum woman?

Management of Refractory Contractions in Obstetrics

For refractory uterine contractions that persist despite standard tocolytic therapy, immediately discontinue any uterotonic agents, position the patient in left lateral decubitus, administer oxygen, provide intravenous hydration with balanced crystalloids, and consider terbutaline as a rescue tocolytic while continuously monitoring fetal status. 1, 2

Initial Assessment and Immediate Actions

Define the Clinical Scenario

• Refractory contractions refer to persistent uterine activity despite maximum recommended doses of parenteral tocolytics, or recurrent preterm labor within three days of successful transition to oral tocolytics 3
• Hypercontractility is characterized by excessive frequency (tachysystole: >5 contractions in 10 minutes), duration (>90-120 seconds), or intensity that may compromise fetal oxygenation 2
• Simple palpation can successfully evaluate hypercontractility unless obesity prevents adequate assessment 2

Stop All Uterotonic Stimulation

• Immediately discontinue oxytocin or any other uterotonic agents when hypercontractility or refractory contractions are identified to prevent fetal compromise 2, 4
• The oxytocin infusion should be stopped abruptly in the event of uterine hyperactivity or fetal distress, as oxytocic stimulation of the uterine musculature will soon wane 4

Resuscitative Measures

Maternal Positioning

• Position the patient in left lateral decubitus to ensure adequate venous return from the inferior vena cava and optimize uteroplacental perfusion 1, 2
• This positioning relieves aortocaval compression and is a higher priority than other interventions 1

Oxygenation and Hydration

• Administer supplemental oxygen to the mother to maximize fetal oxygenation 1, 4
• Provide intravenous hydration with balanced crystalloid solutions (lactated Ringer solution or Plasma-Lyte) rather than normal saline to avoid hyperchloremic metabolic acidosis and renal vasoconstriction 1

Fetal Monitoring

• Continuous cardiotocography (CTG) monitoring is essential when hypercontractility is suspected to assess fetal well-being and guide management 2
• Category I fetal heart rate tracing (normal baseline, moderate variability, accelerations) predicts absence of fetal acidemia and allows for expectant management 5

Pharmacologic Interventions

Tocolytic Therapy

• Terbutaline may be used as a rescue tocolytic to transiently stop contractions, with the understanding that while it improves fetal heart rate tracings compared to untreated controls, there is no proven improvement in neonatal outcomes 1
• Tocolysis is appropriate for preterm gestations when there is a benefit to prolonging pregnancy, but is not indicated at 36 weeks or beyond, even if active labor develops, as neonatal risks are minimal at this gestational age 5

Amnioinfusion

• Consider amnioinfusion for recurrent, moderate to severe variable decelerations associated with refractory contractions, as this intervention reduces decelerations, cesarean delivery rates, low Apgar scores, and low cord arterial pH 1

Critical Pitfalls to Avoid

Contraindicated Medications

• Never use ergometrine or methylergonovine for uterine contraction management in the setting of refractory contractions, as these agents cause sustained uterine contraction and can compromise fetal perfusion 2, 6
• Oxytocin is contraindicated in latent phase labor and should only be used for augmentation in confirmed active labor with slow progress 5

Avoid Premature Intervention

• Do not rely solely on contraction frequency or intensity to guide management decisions; assess labor progress through serial cervical examinations rather than depending on intrauterine pressure measurements 2
• Studies have failed to prove the virtue of using intrauterine pressure transducers to define adequacy of contractions for diagnosis and treatment decisions 2

When Conservative Measures Fail

Escalation Criteria

• If refractory contractions persist with persistent hypotension (MAP <65 mm Hg), persistent hypoxia (oxygen saturation <92% on room air), altered mental status, or lactate ≥4 mmol/L, consider transfer to a higher level of care 1
• For pregnant patients requiring escalation, a level 3 or 4 care center is often necessary 1

Delivery Considerations

• Consider expedited delivery (operative vaginal delivery or cesarean delivery) if fetal heart rate tracing remains abnormal despite intrauterine resuscitation measures 1
• The primary objective is expedited maternal evaluation and treatment, which often leads to improved uteroplacental perfusion and improved fetal condition 1
• If delivery is imminent during transfer considerations, it may be safer to postpone transfer until after childbirth 1

Special Considerations

Postpartum Refractory Bleeding

• For refractory postpartum uterine bleeding, carboprost tromethamine 250 mcg intramuscularly is the treatment of choice, with the majority of successful cases (73%) responding to a single injection 7
• Additional doses may be given at 15-90 minute intervals as dictated by clinical response, with a maximum total dose of 2 mg (8 doses) 7
• Alternatively, oxytocin 10-40 units may be added to 1,000 mL of non-hydrating diluent and infused at a rate necessary to control uterine atony 4

Subclinical Infection

• Subclinical intra-amniotic infection is an uncommon cause of refractory preterm labor in asymptomatic patients with intact membranes, occurring in less than 5% of cases 3
• However, if clinical signs of infection develop (fever, maternal tachycardia, fetal tachycardia, uterine tenderness), consider amniocentesis for culture and initiate broad-spectrum antibiotics 3