Ultrasound guided injection of potassium chloride or methotrexate into ectopic pregnancies: experience from a single institution

Explore potential indications for potassium chloride (KCl) or methotrexate injection of the gestational sac in ectopic pregnancies with ultrasound guidance.

Review techniques and tips based on experience for ultrasound guided injection of the gestational sac.

Review cases performed at our institution including clinical follow up.

Background: Ectopic pregnancy, a pregnancy in which the embryo implants in a location other than the normal uterine cavity, accounts for approximately 1-2% of all pregnancies. The most common location for ectopic pregnancy is within the fallopian tube (greater than 90%), with other locations including interstitial, cesarean scar, peritoneum. Current treatment options of non-ruptured ectopic pregnancy include intramuscular methotrexate administration or laparoscopic surgery {1}. A less commonly described treatment option includes intrasac injection of methotrexate or potassium chloride (KCl). Management of live interstitial and cesarean scar ectopic pregnancies can be especially challenging given the increased risk of hemorrhage, morbidity and potential loss of reproductive capacity with surgical management {2}. Direct intrasac injection is an especially viable treatment option for patient's with poor follow up, who may not be dependable to follow up for routine beta HCG levels after intramuscular methotrexate injection, failed treatment with intramuscular methotrexate, treatment of heterotopic pregnancy, in which the intrauterine pregnancy is desired {3,4}, or in interstitial or cervical scar ectopic pregnancies, in which risk for hemorrhage is increased.

Clinical Findings/Procedure Details: The cases over the past 10 years at our institution will be reviewed, including technique and clinical outcome. This exhibit will also review technical pearls and options to consider, including percutaneous versus transvaginal approach.

Conclusion and/or Teaching Points: Ultrasound guided intrasac injection for ectopic pregnancy is a potentially underdiscussed treatment option for ectopic pregnancy, which in the correct patient population offers advantages over systemic methotrexate treatment and surgery.