Paradoxical response to intravenous terbutaline

Area of Science:

• Obstetrics and Gynecology
• Pharmacology
• Maternal-Fetal Medicine

Background:

• External cephalic version (ECV) is a procedure to externally manipulate a fetus from a breech to a cephalic presentation.
• Tocolytic agents, such as terbutaline, are often administered to relax the uterus and facilitate ECV.
• Uterine hypertonus, characterized by prolonged and strong uterine contractions, can complicate obstetric procedures.

Observation:

• A patient receiving intravenous terbutaline for external cephalic version developed marked uterine hypertonus.
• The uterine hypertonus occurred shortly after the initiation of terbutaline infusion.
• No other apparent stimuli were present that could account for the observed uterine activity.

Findings:

• The temporal association between terbutaline administration and the onset of uterine hypertonus suggests a causal link.
• The patient's response is considered a paradoxical reaction to terbutaline, an agent typically used to relax the uterus.
• This case highlights an atypical pharmacological response to a commonly used tocolytic medication.

Implications:

• Clinicians should be aware of the potential for paradoxical uterine hypertonus with terbutaline during ECV.
• Vigilant monitoring for uterine activity is crucial following terbutaline administration in obstetric procedures.
• Further investigation may be warranted to understand the mechanisms underlying such paradoxical responses to terbutaline.