Middle cerebral artery Doppler before and after fetal spina bifida repair: an indirect sign of hindbrain compression and decompression?

INTRODUCTION: Reduced middle cerebral artery resistance indices (MCA-RI) in fetuses with spina bifida (fSB) are commonly observed. Compression of neuronal pathways in the brainstem due to hindbrain herniation (HH) and disturbed cerebrospinal fluid circulation likely cause an imbalance of the autonomic nervous system. This may increase systemic vasoconstriction and compensatory increase cerebral vasodilation (like brain sparing). Aim of this study was to systematically analyze all fetal MCA-RI before and after fSB repair and to compare their correlation with the presence and post-surgical resolution of HH. METHODS: 173 patients were included. Standardized ultrasound examinations including MCA and umbilical artery (UA) Doppler as well as assessment of HH presence and regression were performed. Fetuses with MCA-RI<5th percentile (P.) before fetal surgery were compared to the group with normal MCA-RI and correlated to the presence of HH before and its regression after fSB repair. RESULTS: 30% (49/161) fetuses showed RI's <5thP before fSB repair. All fetuses had normal UA-RI. 99.4% of fetuses (160/161) showed normal of MCA-RI before delivery. Normalization occurred within a mean of 1.3±1.2 weeks. HH regression was observed in 97% in the group with normal MCA-RI and in 96% in the group with MCA-RI <5thP. before surgery (p = 0.59). Time lapse to HH regression after fSB repair was 1.8±1.7 and 1.9±1.6 weeks respectively. CONCLUSION: In fetuses with MCA-RIs <5.P before fSB repair, a parallel timely course of MCA-RI normalization and HH regression was noted. To suggest common pathogenic factor(s), more studies are needed. However, normalization of the fetal cerebral circulation could be a further benefit of fSB repair.

Pain scores after open fetal spina bifida repair and caesarean section - a longitudinal cohort study.

INTRODUCTION: In fetal surgery, successful pain management is crucial for postoperative mobilization, prophylaxis of contractions, and fast recovery. This study analyzed patient's pain experience after open fetal spina bifida (fSB) repair in comparison to pain scores after the subsequent Caesarean section (C-section). MATERIALS AND METHODS: Data was collected with a questionnaire given to 91 women, who had fSB repair and then C-section at our center between 2019 and 2022. It comprised 12 questions covering different aspects of pain experience and satisfaction with pain therapy and was answered by 67 women after fSB repair and 53 after C-section. Postoperative pain was rated on a Likert scale from 0 (slight/rarely) to 100 (strongest/always). Outcomes after fSB repair were compared to those after C-section. Additionally, subgroup analysis compared outcomes of women with different pain levels (group 1-5) after fSB repair. RESULTS: Compared to women after C-section women after fSB repair reported significantly higher maximum pain scores (MPS) (p = 0.03), higher sleep disturbance due to pain (p = 0.03), and sedation rates (p = 0.001) as side effect from pain therapy. No differences were found regarding feelings of insecurity (p = 0.20) or helplessness (p = 0.40), as well as involvement in (p = 0.3) and satisfaction with pain therapy (p = 0.5). Subgroup analysis revealed that women with higher MPS after fSB repair were significantly more often non-Caucasians (p = 0.003) and more often affected by pain while lying in bed (p = 0.007) and during mobilization (p = 0.005). Additionally they reported higher rates of dizziness (p = 0.02) and lower satisfaction rates with pain therapy (p = 0.03). Postoperative complication rate did not differ among groups. CONCLUSION: Although women after fSB repair reported higher MPS compared to after C-section, the current pain management was generally perceived as satisfactory.

Enhanced Recovery after Surgery in Open Fetal Spina Bifida Repair.

INTRODUCTION: For open fetal spina bifida (fSB) repair, a maternal laparotomy is required. Hence, enhanced maternal recovery after surgery (ERAS) is paramount. A revision of our ERAS protocol was made, including changes in operative techniques and postoperative pain management. This study investigates eventual benefits. METHODS: Our study included 111 women with open fSB repair at our center. The old protocol group (group 1) either received a transverse incision of the fascia with transection of the rectus abdominis muscle (RAM) or a longitudinal incision of the fascia without RAM transection, depending on placental location. The new protocol required longitudinal incisions in all patients (group 2). Postoperative pain management was changed from tramadol to oxycodone/naloxone. Outcomes of the two different protocol groups were analyzed and compared regarding the primary endpoint, the length of hospital stay (LOS) after fetal surgery, as well as regarding the following secondary endpoints: postoperative pain scores, day of first mobilization, removal of urinary catheter, bowel movement, and the occurrence of maternal and fetal complications. RESULTS: Out of 111 women, 82 (73.9%) were in group 1 and 29 (26.1%) were in group 2. Women in group 2 showed a significantly shorter LOS (18 [14-23] days vs. 27 [18-39] days, p = 0.002), duration until mobilization (3 [2-3] days vs. 3 [3-4] days, p = 0.03), and removal of urinary catheter (day 3 [3-3] vs. day 4 [3-4], p = 0.004). Group 2 less often received morphine subcutaneously (0% vs. 35.4%, p < 0.001) or intravenously (0% vs. 17.1%, p = 0.02) but more often oxycodone (69.0% vs. 18.3%, p < 0.001). No significant differences were seen regarding pain scores, bowel movement, and maternal and/or fetal complications. CONCLUSION: The new ERAS protocol that combined changes in surgical technique and pain medication led to better outcomes while reducing LOS. Continuous revisions of current ERAS protocols are essential to improve patient care continuously.

Fetal Spina Bifida Repair in Obese Mothers: Is Maternal and Fetal Safety Compromised?

INTRODUCTION: The Management of Myelomeningocele Study (MOMS) eligibility criteria preclude in utero surgery for fetal spina bifida (fSB) when the maternal body mass index (BMI) is ≥35 kg/m2. Some centers still respect this criterion, while others, like ours, do not. This study aimed to assess whether maternal and fetal safety is compromised with higher maternal BMIs. METHODS: Data of 192 patients with open fSB repair at our center were retrospectively analyzed. According to their BMI, patients were divided into three groups: group 1 (BMI <30 kg/m2), group 2 (BMI 30-35 kg/m2), and group 3 (BMI >35 kg/m2). Subgroup analysis was performed to assess differences in maternal and fetal outcomes. Additionally, complications were divided into grades 1 to 5 according to their severity and outcome consequences and compared among groups. RESULTS: Out of 192 patients, 146 (76.0%) had a BMI <30 kg/m2, 28 (14.6%) had a BMI 30-35 kg/m2, and 18 (9.4%) had a BMI >35 kg/m2. Significant differences occurring more often in either group 2 or 3 compared to group 1 were maternal wound seroma (50% or 56% vs. 32%, p = 0.04), amniotic fluid leakage (14% or 6% vs. 2%, p = 0.01) as well as vaginal bleeding (11% or 35% vs. 9%, p = 0.01). On the contrary, duration of tocolysis with atosiban was shorter in patients with BMI >30 kg/m2 (4 or 5 vs. 6 days, p = 0.01). When comparing severity of maternal or fetal complications, grade 1 intervention-related complications occurred significantly more often in group 3 compared to group 1 or 2 (78% vs. 45% or 57%, p = 0.02). Gestational age at delivery was around 36 weeks in all groups without significant differences. CONCLUSION: This investigation did not identify clinically relevant maternal and/or fetal outcome problems related to BMIs >35 kg/m2. Additional studies are however needed to confirm our results.

Tissue Glue-Based Sealing Patch for the in vivo Prevention of Iatrogenic Prelabor Preterm Rupture of Fetal Membranes.

INTRODUCTION: One of the main concerns for all fetal surgeries is the risk of preterm delivery due to the preterm prelabor rupture of the fetal membranes (iPPROM). Clinical approaches to seal fetal membrane (FM) defects are missing due to the lack of appropriate strategies to apply sealing biomaterials at the defect site. METHODS: Here, we test the performance of a previously developed strategy to seal FM defects with cyanoacrylate-based sealing patches in an ovine model up to 24 days after application. RESULTS: Patches sealed tightly the fetoscopy-induced FM defects and remained firmly attached to the defect over 10 days. At 10 days after treatment, 100% (13/13) of the patches were attached to the FMs, and 24 days after treatment 25% (1/4) of the patches placed in CO2 insufflation, and 33% (1/3) in NaCl infusion remained. However, all successfully applied patches (20/24) led to a watertight sealing at 10 or 24 days after treatment. Histological analysis indicated that cyanoacrylates induced a moderate immune response and disrupted the FM epithelium. CONCLUSION: Together, these data show the feasibility of minimally invasive sealing of FM defects by locally gathering tissue adhesive. Further development to combine this technology with refined tissue glues or healing-inducing materials holds great promise for future clinical translation.

Subsequent Pregnancy Outcomes after Open in utero Spina Bifida Repair.

INTRODUCTION: Fetal spina bifida (SB) repair is a distinct therapeutic option in selected cases. Since this procedure may not only be associated with short-term obstetrical complications, the aim of this study was to assess the outcomes of subsequent pregnancies after open fetal SB repair. METHODS: 138 patients having had open fetal SB repair at our center received a questionnaire regarding the occurrence, course, and outcome of subsequent pregnancies. Additionally, medical records were reviewed. All subsequent pregnancies with complete outcome data that progressed beyond 20 gestational weeks (GW) were included for further analysis. RESULTS: 70% of all women answered the questionnaire. Out of this cohort, 35 subsequent pregnancies were reported in 29% of women. The rate of early pregnancy loss including elective terminations was 14%. All 29 pregnancies processing >20 GW ended in live births without preterm births <34th GW. Mean gestational age at delivery was 37.3 ± 1.4 GW. Uterine rupture occurred in two cases (7%) and uterine thinning/dehiscence was present in six cases (21%). No maternal transfusions were required. CONCLUSION: When counseling women undergoing open fetal SB repair, one should consider possible risks for subsequent pregnancies, especially the one of uterine dehiscence and rupture that is similar compared to numbers reported after classical cesarean deliveries.

Fetal-Maternal Surgery for Spina Bifida in a HIV-Infected Mother.

INTRODUCTION: In select cases, in utero surgery for myelomeningocele (MMC) leads to better outcomes than postnatal repair. However, maternal HIV infection constitutes a formal exclusion criterion due to the potential of vertical HIV transmission. Encouraged by a previous case of a successful fetal spina bifida repair in a Hepatitis Bs antigen-positive woman, a plan was devised allowing for fetal surgery. CASE REPORT: In utero MMC repair was performed although the mother was HIV-infected. To minimize the risk of in utero HIV transmission, the mother was treated by highly active antiretroviral therapy throughout gestation as well as intravenous zi-dovudine administration during maternal-fetal surgery. The mother tolerated all procedures very well without any sequelae. The currently 20 month-old toddler is HIV negative and has significantly benefitted from fetal surgery. DISCUSSION/CONCLUSION: This case shows that maternal HIV is not a priori a diagnosis that excludes fetal surgery. Rather, it might be a surrogate for moving towards personalized medicine and away from applying too rigorous exclusion criteria in the selection of candidates for maternal-fetal surgery.

In vivo Sealing of Fetoscopy-Induced Fetal Membrane Defects by Mussel Glue.

INTRODUCTION: The benefits of fetal surgery are impaired by the high incidence of iatrogenic preterm prelabor rupture of the fetal membranes (iPPROM), for which chorioamniotic separation has been suggested as a potential initiator. Despite the urgent need to prevent iPPROM by sealing the fetoscopic puncture site after intervention, no approach has been clinically translated. METHODS: A mussel-inspired biomimetic glue was tested in an ovine fetal membrane (FM) defect model. The gelation time of mussel glue (MG) was first optimized to make it technically compatible with fetal surgery. Then, the biomaterial was loaded in polytetrafluoroethylene-coated nitinol umbrella-shaped receptors and applied on ovine FM defects (N = 10) created with a 10 French trocar. Its sealing performance and tissue response were analyzed 10 days after implantation by amniotic fluid (AF) leakage and histological methods. RESULTS: All ewes and fetuses recovered well after the surgery, and 100% ewe survival and 91% fetal survival were observed at explantation. All implants were tight at explantation, and no AF leakage was observed in any of them. Histological analysis revealed a mild tissue response to the implanted glue. CONCLUSION: MG showed promising properties for the sealing of FM defects and thereby the prevention of preterm birth. Studies to analyze the long-term tissue response to the sealant should be performed.

Fetal surgery for spina bifida in Zurich: results from 150 cases.

PURPOSE: Over the past 10 years, over 150 fetal spina bifida surgeries were performed at the Zurich Center for Fetal Diagnosis and Therapy. This study looks at surrogates for success and failure of this approach. METHODS: We focused on key outcome parameters including hydrocephalus shunt rate at one year, bladder control at 4, independent ambulation at 3 years, and maternal, fetal, and neonatal complications. RESULTS: From the first 150 patients undergoing fetal surgery for spina bifida, 148 (98.7%) were included in the study. Maternal-fetal surgery was uneventful in 143/148 (97%) cases. Intraoperative problems included resuscitation in 4/148 fetuses (2.7%). 1/148 fetuses (0.7%) died on postoperative day 4. Maternal complications included chorioamniotic membrane separation in 22/148 (15%), lung embolism in 3/148 (2.1%), chorioamnionitis in 2/148 (1.4%), AV-block III and uterine rupture in 1/148 each (0.7%). 1/148 (0.7%) newborn death was recorded. Hindbrain herniation was identified preoperatively in 132/148 (90%) fetuses and resolved completely in 119/132 (90%). At one year, 39/106 (37%) children had required a CSF diversion. At 4 years, 4/34 patients (12%) had normal bladder control. At 3 years, 48/57 (84%) walked independently. CONCLUSION: A majority of patients benefitted from prenatal intervention, in that the shunt rate was lower and the rates of continent and walking patients were higher than reported with postnatal care.