Ultrasound in Obstetrics & Gynecology最新文献

Objective: There are conflicting data on whether fetoscopic laser photocoagulation (FLP) of placental anastomoses for the treatment of twin-to-twin transfusion syndrome (TTTS) is associated with lower rates of overall survival. The objective of this study was to characterize twin survival and associated morbidity according to the gestational age at which FLP was performed.

Methods: This was a secondary analysis of data collected prospectively on patients with a monochorionic diamniotic (MCDA) twin pregnancy who underwent FLP for TTTS at two centers between January 2011 and December 2022. Patients were divided into six groups according to gestational age at the time of FLP: < 18 weeks, 18 + 0 to 19 + 6 weeks, 20 + 0 to 21 + 6 weeks, 22 + 0 to 23 + 6 weeks, 24 + 0 to 25 + 6 weeks and ≥ 26 weeks. Demographic characteristics, sonographic characteristics of TTTS and operative characteristics were compared across the gestational age epochs. Outcomes, including overall survival, preterm delivery (PTD), preterm prelabor rupture of membranes (PPROM), intrauterine fetal demise (IUFD) and neonatal demise (NND), were also compared across gestational age epochs. Multivariate analysis was performed by fitting logistic regression models for these outcomes. Kaplan-Meier curves were constructed to compare the interval from PPROM to delivery between gestational age epochs.

Results: There were 768 patients that met the inclusion criteria. The rate of dual twin survival was 61.3% for cases in which FLP was performed before 18 weeks, compared with 78.0%-86.7% when FLP was performed at ≥ 18 weeks' gestation. This appears to be driven by an increased rate of donor IUFD following FLP performed before 18 weeks (28.0%) compared with ≥ 18 weeks (9.3-14.1%). Rates of recipient IUFD and NND and donor NND were similar regardless of gestational age at FLP. The rate of PPROM was higher for FLP conducted at earlier gestational ages, ranging from 45.6% for FLP before 18 weeks to 11.9% for FLP performed at 24 + 0 to 25 + 6 weeks' gestation. However, gestational age at delivery was similar across gestational age epochs, with a median of 31.7 weeks. On multivariate analysis, donor twin loss was associated with FLP before 18 weeks, even after adjusting for selective fetal growth restriction, Quintero stage and other covariates. PPROM and PTD were also associated with FLP performed before 18 weeks after adjusting for cervical length, placental location, trocar size, laser energy and amnioinfusion.

Conclusions: FLP performed at earlier gestational ages is associated with lower overall survival, which is driven by the increased risk of donor IUFD, as opposed to differences in the rate of PPROM or PTD. Parental counseling regarding twin survival should account for the gestational age at which patients present with TTTS. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Objective: To determine consensus, using Delphi methodology, on the critical procedural steps for intravascular intrauterine transfusion (IUT) for the treatment of fetal anemia.

Methods: We conducted a two-part Delphi survey of international experts in fetal intervention. The first round of the survey proposed 32 potentially critical steps for the IUT procedure. Participants were asked to rate all steps on a Likert scale ranging from 1 (not important) to 5 (absolutely essential). We calculated the mean Likert score and 95% CI for all steps. Procedural steps were determined to be critical if the lower bound of the 95% CI was ≥ 3.0 and were excluded if the upper bound of the 95% CI was ≤ 3.5. In the second round of the survey, participants were asked specific questions regarding parameters associated with the procedural steps determined to be critical in the first round.

Results: Overall, 49 individuals from 24 different countries (six continents) participated in both rounds of the Delphi survey. The median length of experience in fetal medicine was 21 (range, 4-38) years. The median number of IUT procedures performed annually per respondent was 20 (range, 2-80). Of the 32 proposed procedural steps, 20 were determined to be critical and 12 non-critical procedural steps were excluded. Respondents indicated that an individual should perform a median of 20 (range, 10-50) IUT procedures during training to attain competency, and that the median number of IUT procedures required annually to maintain competency was 10 (range, 5-20). There was marked variation between respondents in how they performed the following critical IUT procedural steps: preparation of donor blood, preoperative medication, maternal anesthesia, site chosen for cordocentesis, use of fetal paralysis, method for determining fetal hematocrit, postoperative care and decision to schedule a subsequent IUT.

Conclusions: The findings of this international Delphi survey can be used to standardize the approach to performing IUT. An experienced fetal interventionist should perform the procedure, and in centers in which IUT is performed infrequently, referral to a more experienced center should be considered. Calculating the specific volume of blood to transfuse at the start of the procedure and undertaking continuous fetal heart-rate monitoring once the gestational-age threshold for viability is reached were ranked highest in the intra- and postoperative phases of the procedure, respectively. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.