Fetal Instability and Resuscitative Management During Fetal Intervention: A Retrospective, Descriptive Analysis of 245 Fetal Cardiac and Spina Bifida Procedures.

OBJECTIVE

The heterogeneity of fetal surgery has led to variability in the nature and frequency of fetal instability. Understanding these differences is critical for optimizing management.

METHODS

We reviewed all fetal atrial septal interventions (FASI) and fetoscopic myelomeningocele (fMMC) repairs with fetal instability performed at our institution between March 2012 and April 2025. We described and compared the frequency, timing, etiology, and management of fetal instability.

RESULTS

During the study period, 28 unique patients underwent 35 FASI procedures, and 210 patients underwent fMMC repair. Fetal instability occurred in 51 of 245 cases (20.8%), with rates varying significantly by procedure type (30/35 FASI, 85.7% vs. 21/210 fMMC, 10.0%, p < 0.01). The causes of fetal instability requiring resuscitation differed by procedure. In FASI, all instability was procedure-related, whereas instability during fMMC repairs was most often related to the uterine environment. Invasive resuscitative interventions (e.g., pericardiocentesis) were used exclusively in FASI. In fMMC repair, less invasive interventions (e.g., repositioning) were more commonly employed.

CONCLUSIONS

Fetal instability is common during fetal interventions, with higher rates and more invasive resuscitation during FASIs compared with fMMC repairs. The causes and interventions employed vary by procedure type, highlighting the need for tailored intraoperative strategies.