A new and more effective feticide technique in late termination of pregnancy: potassium chloride injection into the interventricular septum of the fetal heart

Abstract

Objective: This study sought to compare the efficacy and outcomes of fetal intracardiac intraventricular and interventricular septal potassium chloride (KCl) injections during the induced fetal demise process in a cohort of pregnant women with severe fetal abnormality who opted for late termination of pregnancy (TOP).

Materials and methods: This study consisted of 158 pregnant women who requested late TOP for severe fetal abnormality between 22 and 36 weeks of pregnancy. Participants were randomly assigned with the simple randomization procedure to one of two feticide procedure groups: the intraventricular KCl injection group and the interventricular septal KCl administration group. We studied the clinical outcomes of both the feticide procedures.

Results: The median total dose of strong KCl was significantly lower in the interventricular septal KCl administration group (3 mL) than in the intraventricular KCl injection group (5 mL, p < 0.001). The median time to reach asystole and the median total duration of the procedure was significantly shorter in the interventricular septal KCl administration group (42 s and 85 s, respectively) than in the intraventricular KCl injection group (115 s and 150 s, respectively, p < 0.001). We detected a statistically significant correlation between the gestational week at feticide and the total dose of KCl (r = 0.705, p < 0.001), time to reach asystole (r = 0.653, p < 0.001), and total duration of the procedure (r = 0.683, p < 0.001).

Conclusion: KCl administered directly into the interventricular septum induces immediate and permanent fetal cardiac asystole with a 100% of success rate without comprising maternal safety. We did not observe any maternal complications related to the procedure in our cases. Since the consequences of failed feticide procedure are challenging for both parents and healthcare providers, and providers are also concerned about potential legal implications regarding an unintended live birth, it is crucial to guide a strict protocol to confirm permanent fetal cardiac asystole.

Keywords: Feticide; Interventricular septal injection; Late termination of pregnancy; Potassium chloride.