Anesthetic recommendations for maternal and fetal safety in nonobstetric surgery: a balancing act.

PURPOSE OF REVIEW: Nonobstetric surgery during pregnancy is associated with maternal and fetal risks. Several physiologic changes create unique challenges for anesthesiologists. This review highlights physiologic changes of pregnancy and presents clinical recommendations based on recent literature to guide anesthetic management for the pregnant patient undergoing nonobstetric surgery. RECENT FINDINGS: Nearly every anesthetic technique has been safely used in pregnant patients. Although it is difficult to eliminate confounding factors, exposure to anesthetics could endanger fetal brain development. Perioperative fetal monitoring decisions require an obstetric consult based on anticipated maternal and fetal concerns. Given the limitations of fasting guidelines, bedside gastric ultrasound is useful in assessing aspiration risk in pregnant patients. Although there is concern about appropriateness of sugammadex for neuromuscular blockade reversal due its binding to progesterone, preliminary literature supports its safety. SUMMARY: These recommendations will equip anesthesiologists to provide safe care for the pregnant patient and fetus undergoing nonobstetric surgery.

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.

"I don't have a telephone to the fetus": Clinicians' conceptions of fetal patienthood in maternal-fetal surgery counseling.

RATIONALE: Maternal fetal surgery (MFS) has developed rapidly since the 1960s and centers for fetal diagnosis and therapy (CFDT) have proliferated. As a result, CFDT clinicians have intervened with fetuses through pregnant bodies for decades, yet the patienthood status of the fetus and its implications for the pregnant person's autonomy have been relatively unexamined. OBJECTIVE: Our overall research aims were threefold: (1) to explore how clinicians train for and provide counseling for MFS; (2) to examine how clinicians assess fetal patienthood and its implications; and (3) to understand clinicians' professed needs and their recommendations for education and training for the provision of MFS counseling. This focuses on aim two. METHOD: In this qualitative study, conducted using in-depth interviews, we examined how 20 clinicians from 17 different sites understood fetal patienthood, how that affected their counseling of pregnant patients, and whether they drew on extant ethical frameworks for guidelines. RESULTS: We identified three major themes: 1) Clinicians entered fetal surgery consultations with assumptions about fetal patienthood (frequently informed by beliefs about fetal viability, maternal attachment, and disciplinary perspectives); 2) they consciously assessed their pregnant patients' connections to their fetus to inform or re-calibrate their own understandings of fetal patienthood; and 3) they used a threshold -based conceptualization whereby the fetus achieved patienthood after crossing a symbolic boundary, often related to the clinician's ability to intervene. CONCLUSIONS: Few clinicians invoked an extant ethical framework to determine fetal patienthood; most asserted that they did not view directive counseling toward MFS as appropriate, instead working diligently to protect pregnant patients' autonomy and rights to self-determination.

Intrauterine Correction of Fetal Myelomeningocele Through Minihysterotomy.

Spina bifida is the most common congenital central nervous system anomaly, resulting in lifelong neurologic, urinary, motor, and bowel disability.1 Its most frequent form is myelomeningocele, characterized by spinal cord extrusion into a sac filled with cerebrospinal fluid.1 We report the case of a 28-year-old pregnant female with no comorbidities. At 16 weeks of pregnancy, fetal ultrasound presented ventriculomegaly, cerebellar herniation, and lumbar myelomeningocele. At 22 weeks, intrauterine surgical correction was performed (Video 1). A minihysterotomy spanning approximately 3 cm was performed. The defect was opened, and the neural placode was dissected and released. This was followed by the isolation of the peripheric dura, which was molded into a tube and closed with watertight suture. Finally, the minihysterotomy was sutured and the skin was closed. The pregnancy followed its course with no complications, and the child was born at term with the lesion closed and no necessity of intensive care. Recent studies have demonstrated that infants who undergo open in utero myelomeningocele repair have better neurologic outcomes than those who are treated after birth.1,2 However, maternal morbidity is nonnegligible with the classical open surgery.2 Peralta et al2 propose a modification of the classic 6.0- to 8.0-cm hysterotomy in which the same multilayer correction of the spinal defect is performed through a 2.5- to 3.5-cm hysterotomy. This modification, called minihysterotomy, has been successfully performed outside of its creation center and was associated with reduced risks of preterm delivery and maternal, fetal, and neonatal complications.2,3.

Hepatic arterial buffer response: activation in donor fetuses and the effect of laser ablation of intertwin anastomosis.

OBJECTIVES: Hepatic arterial buffer response (HABR) is an important defence mechanism for maintaining liver blood flow. It is suspected that HABR is active in monochorionic diamniotic twins (MCDA) with twin-to-twin transfusion syndrome (TTTS) where donor compensates a setting of volume depletion and the recipient an overload. The present study investigates whether in TTTS, HABR is active in donor and/or recipient individually and try to determine if the activation of HABR is a direct response to TTTS. METHODS: Hepatic artery (HA) peak systolic velocity (PSV) was measured in normal MCDA fetuses and TTTS. Correlation with relevant fetal Dopplers and characteristics were determined. Z-scores for HA-PSV (HAV-Z) were calculated and its association with TTTS in donors and recipients were determined as well as changes in HAV-Z after laser treatment. RESULTS: In this study 118 MCDA were included, 61.9 % normal and 38.1 % TTTS. Of the TTTS 22 required laser treatment. A total of 382 scans were performed in normal group and 155 in TTTS. Our data demonstrates that in donors HAV-Z was 2.4 Z-scores higher compared to normal fetuses (ß=2.429 95 % CI 1.887, 2.971; p<0.001) and after laser treatment HAV-Z reduced (ß=-1.829 95 % CI -2.593, -1.064; p<0.001). There was no significant difference between recipients and normal (ß=-0.092 95 % CI -0.633, 0.449; p=0.738). CONCLUSIONS: HABR is active in TTTS, promoting an increased hepatic blood flow in donors. The activation is direct response to TTTS as shown by the reduction in HAV-Z after laser. This finding provides important insights into the pathophysiology of TTTS.

Percutaneous fetal endoscopic third ventriculostomy for severe isolated cerebral ventriculomegaly.

OBJECTIVE: To demonstrate the feasibility and preliminary results of percutaneous fetal endoscopic third ventriculostomy (ETV) in human fetuses (pfETV) with isolated progressive and/or severe bilateral cerebral ventriculomegaly (IPSBV). METHODS: The initial results of pfETV for IPSBV were described. Perioperative, perinatal and postnatal variables were described. The Ages and Stages Questionnaire (ASQ-3), 3rd edition (ASQ-3) was used for follow-up of all infants. RESULTS: Successful pfETV was performed in 10/11 (91%) fetuses, at a median gestational age (GA) of 28.7 weeks (25.3-30.7). There were no perioperative complications. After pfETV, 70% (7/10) of the fetuses had a decreased or stabilized lateral ventricle atria|lateral ventricle's atria. The median GA at delivery was 38.2 weeks (35.9-39.3). There were no perinatal complications. The postnatal ventriculoperitoneal shunt rate was 80% (8/10). Among neonates/infants who had prenatal stabilization or a decrease in the LVAs, 4 (4/7: 57.1%) had abnormal scores on the ASQ-3. Among neonates/infants that experienced prenatal increases in the LVAs, all of them (3/3: 100%) had abnormal scores on the ASQ-3. CONCLUSION: Percutaneous ETV is feasible in human fetuses with progressive and/or severe cerebral ventriculomegaly and seems to be a safe procedure for both the mother and the fetus.

Catheter ablation of atrioventricular nodal reentrant tachycardia, when AVNRT presented as a fetus or infant.

BACKGROUND: Atrioventricular nodal reentrant tachycardia (AVNRT) does not commonly present during infancy. Although relative safety of catheter ablation of AVNRT has been demonstrated in pediatrics, this procedure is rarely indicated in children <15 kg. METHODS: Retrospective review of seven cases of AVNRT that presented in children younger than 1 year of age and required catheter ablation for definitive management. Electrophysiology (EP) study was planned with two or three catheters. Area of ablation determined by voltage mapping, propagation sinus wave collision and slow pathway potential location. Ablation performed with cryothermal energy. No fluoroscopy was used. RESULTS: Presentation ranged from 36 weeks of gestation to 11 months of age. Two presented in fetal life and two in the neonatal period. The median age of ablation was 20 months (range 17-31 months). The median weight at ablation was 11.4 kg (range 8.9-14.9 kg). Median follow-up time was 16 months. All had typical AVNRT. The median tachycardia cycle length was 216 ms. 100% successful rate using cryoablation. No complications. No recurrence of tachycardia during the follow-up period. CONCLUSION: Slow AV nodal pathway cryoablation may be safely performed, with good short and medium-term outcomes in patients under 15 kg.

Fetal neurosurgery.

Among fetal surgical procedures, neurosurgery stands out due to the number of cases and the possibility of developing new procedures that can be performed in the fetal period. To perform fetal neurosurgical procedures, there is a need for specialized centers that have experts in the diagnosis of fetal pathologies and a highly complex obstetrics service with specialized maternal-fetal teams associated with a pediatric neurosurgery center with expertise in the diverse pathologies of the fetus and the central nervous system that offers multidisciplinary follow-up during postnatal life. Services that do not have these characteristics should refer their patients to these centers to obtain better treatment results. It is essential that the fetal neurosurgical procedure be performed by a pediatric neurosurgeon with extensive experience, as he will be responsible for monitoring these patients in the postnatal period and for several years. The objective of this manuscript is to demonstrate the diagnostic and treatment possibilities, in the fetal period, of some neurosurgical diseases such as hydrocephalus, tumors, occipital encephalocele, and myelomeningocele.

Prenatal Spina Bifida Repair: Defendable Trespassing of MOMS Criteria Results in Commendable Personalized Medicine.

INTRODUCTION: We hypothesize that after publication of the quintessence of the MOMS trial, eligibility criteria for prenatal spina bifida (SB) repair may be modified if a tenable argumentation underlies this decision. METHODS: Our first 154 fetal surgery patients were analyzed with particular focus on how many, which, and why the original eligibility criteria, set forth by the MOMS Trial Protocol, were disobeyed, and what the eventually detectable, negative and positive impacts of these deviations on outcomes were. RESULTS: A total of 152 patients (2 missing consent) were included (100%). In 69 patients (45.4%), a total of 89 eligibility criteria were disobeyed. In 54 (35.6%) cases, the following maternal criteria were concerned: gestational age at operation of >25+6 weeks in 17 (11.2%), uterine pathologies in 13 (8.6%) women, preoperative BMI ≥35 kg/m2 in 12 (7.9%), previous hysterotomy in 7 (4.6%), previous prematurity in 3 (2%), HIV/hepatitis B in 2 (1.3%), psychosocial issues in 2 (1.3%), and placenta praevia in 1 (0.7%). In 32 (21.1%) cases, fetal criteria were disobeyed 34 times: Fetal anomaly unrelated to SB in 19 (12.5%), no/minimal evidence of hindbrain herniation in 13 (8.6%), and severe kyphosis in 2 (1.3%). We could not identify cases where non-observation of criteria led to clear-cut maternal and/or fetal disadvantages. CONCLUSION: This study shows that MOMS trial eligibility criteria for prenatal SB repair should be modified or even abandoned with adequate medical and ethical argumentation, and with written parental informed consent after non-directive, full disclosure counseling. This clear-cut change of paradigm is a necessity as it leads toward personalized medicine, allowing more fetuses to benefit from fetal surgery than would have benefitted with the former, published, MOMS criteria in place.

Postnatal Myelomeningocele Repair in the United States: Rates and Disparities Before and After the Management of Myelomeningocele Study Trial.

BACKGROUND AND OBJECTIVES: Evolving technologies have influenced the practice of myelomeningocele repair (MMCr), including mandatory folic acid fortification, advances in prenatal diagnosis, and the 2011 Management of Myelomeningocele Study (MOMS) trial demonstrating benefits of fetal over postnatal MMCr in select individuals. Postnatal MMCr continues to be performed, especially for those with limitations in prenatal diagnosis, health care access, anatomy, or personal preference. A comprehensive, updated national perspective on the trajectory of postnatal MMCr volumes and patient disparities is absent. We characterize national trends in postnatal MMCr rates before and after the MOMS trial publication (2000-2010 vs 2011-2019) and examine whether historical disparities persist. METHODS: This retrospective, cross-sectional analysis queried Nationwide Inpatient Sample data for postnatal MMCr admissions. Annual and race/ethnicity-specific rates were calculated using national birth registry data. Time series analysis assessed for trends relative to the year 2011. Patient, admission, and outcome characteristics were compared between pre-MOMS and post-MOMS cohorts. RESULTS: Between 2000 and 2019, 12 426 postnatal MMCr operations were estimated nationwide. After 2011, there was a gradual, incremental decline in the annual rate of postnatal MMCr. Post-MOMS admissions were increasingly associated with Medicaid insurance and the lowest income quartiles, as well as increased risk indices, length of stay, and hospital charges. By 2019, race/ethnicity-adjusted rates seemed to converge. The mortality rate remained low in both eras, and there was a lower rate of same-admission shunting post-MOMS. CONCLUSION: National rates of postnatal MMCr gradually declined in the post-MOMS era. Medicaid and low-income patients comprise an increasing majority of MMCr patients post-MOMS, whereas historical race/ethnicity-specific disparities are improving. Now more than ever, we must address disparities in the care of MMC patients before and after birth.

Abdominal testicular vessel distribution in human fetuses - basis for fowler-Stephens surgery.

PURPOSE: To analyze the histology and distribution of abdominal testicular vessels in human fetuses Patients and Methods: We studied 19 fetuses (34 testes) ranging in age from 12 to 19 weeks post-conception. The fetuses were evaluated regarding crown-rump length (CRL), total length (TL) and body weight immediately before dissection. Each testis was dissected and embedded in paraffin, from which 5 µm thick sections were obtained and stained with Masson's trichrome and Anti-CD31 antibody to quantify the vessels. The stereological analysis was carried out with the Image Pro and Image J programs, using a grid to determine volumetric densities (Vv). Means were statistically compared using the unpaired T-test (p<0.05). RESULTS: The fetuses presented mean weight of 222.5g, mean CRL of 15.3 cm and mean TL of 23.2 cm. All testes were in the abdominal position. The mean percentage of vessels (Vv) in the upper portion of the testis was 7.6% (4.6 to 15%) and in the lower portion the mean was 5.11% (2.3 to 9.8%), with a significant difference (p=0.0001). In the analysis between the upper portion of the right and left testes (p=0.99) and in the analysis of the lower portion of the right and left testes (p=0.83), we did not observe significant differences. CONCLUSION: The upper portion of the abdominal testis in human fetuses had a higher concentration of vessels than the lower portion. These results suggest that manipulation of the lower end of the testis during Fowler-Stephens surgery should be avoided in order to preserve the collateral circulation.

The value and limitations of using predetermined criteria in decision making for maternal-fetal interventions.

Maternal-fetal interventions-such as prenatal fetal myelomeningocele (MMC) repair-are at the forefront of clinical innovation within maternal-fetal medicine, pediatric surgery, and neonatology. Many centers determine eligibility for innovative procedures using pre-determined inclusion and exclusion criteria based on seminal studies, for example, the "Management of Myelomeningocele Study" for prenatal MMC repair. What if a person's clinical presentation does not conform to predetermined criteria for maternal-fetal intervention? Does changing criteria on a case-by-case basis (i.e., ad hoc) constitute an innovation in practice and flexible personalized care or transgression of commonly held standards with potential negative consequences? We outline principle-based, bioethically justified answers to these questions using fetal MMC repair as an example. We pay special attention to the historical origins of inclusion and exclusion criteria, risks and benefits to the pregnant person and the fetus, and team dynamics. We include recommendations for maternal-fetal centers facing these questions.

Laparoscopy-assisted percutaneous correction of abdominal wall defects in the umbilical region in a cadaveric model of bovine fetus.

Abdominal wall defects in calves are commonly diagnosed and treated via laparotomy. This technique has witnessed several advancements in the management of these disorders. This study aimed to create a study model and evaluate the feasibility of video-assisted percutaneous correction of abdominal wall defects in bovine fetuses (corpses) compared with the conventional technique. Sixteen bovine fetuses from pregnant cows slaughtered in slaughterhouses were included in this study. The fetuses were categorized into the control group (CG, n = 8), which was subjected to umbilical abdominorrhaphy via laparotomy, and the video-surgical group (VG, n = 8), which received video-assisted percutaneous sutures with two lateral accesses on the right flank. An abdominal wall defect was created in the VG group to generate a study model, which was corrected using the laparoscopic technique. The procedures were performed in two steps. The first step consisted of creating an abdominal wall defect in the umbilical region by laparoscopic approach in an iatrogenic manner (Step 1: E1). The second stage consisted of conventional abdominorrhaphy of the umbilical region wall defect in the CG group and video-assisted percutaneous suturing of the edges of the iatrogenic abdominal wall defect in the VG group, until reversal of the laparoscopic accesses (Step 2: E2). Step 1 showed no statistically significant difference between the two groups. However, a significant statistical difference (p < 0.0001) was observed between the two groups in step 2. The surgical time of step 2 was longer in the CG group (33.10 ± 0.43 minutes) than that in the VG group (10.13 ± 0.68 minutes, p < 0.0001), and the total surgical time was also longer in the CG group (38.48 ± 0.35 minutes) than that in the VG group (15.86 ± 0.67 minutes). The proposed laparoscopic technique allowed the creation of a study model for video-assisted percutaneous suturing with two portals and reduced the surgical time compared with the conventional technique. However, this method needs to be studied further in live animals.

Global Policy and Practice for Intrauterine Fetal Resuscitation During Fetal Surgery for Open Spina Bifida Repair.

Importance: Globally accepted recommendations suggest that a woman should be between 19 weeks and 25 weeks plus 6 days of pregnancy to be considered eligible for fetal closure of open spina bifida. A fetus requiring emergency delivery during surgery is therefore potentially considered viable and thus eligible for resuscitation. There is little evidence, however, to support how this scenario is addressed in clinical practice. Objective: To explore current policy and practice for fetal resuscitation during fetal surgery for open spina bifida in centers undertaking fetal surgery. Design, Setting, and Participants: An online survey was designed to identify current policies and practices in place to support fetal surgery for open spina bifida, exploring experiences and management of emergency fetal delivery and fetal death during surgery. The survey was emailed to 47 fetal surgery centers in 11 countries where fetal spina bifida repair is currently performed. These centers were identified through the literature, the International Society for Prenatal Diagnosis center repository, and an internet search. Centers were contacted between January 15 and May 31, 2021. Individuals volunteered participation through choosing to complete the survey. Main Outcomes and Measures: The survey comprised 33 questions of mixed multiple choice, option selection, and open-ended formats. Questions explored policy and practice supporting fetal and neonatal resuscitation during fetal surgery for open spina bifida. Results: Responses were obtained from 28 of 47 centers (60%) in 11 countries. Twenty cases of fetal resuscitation during fetal surgery during the last 5 years were reported across 10 centers. Four cases of emergency delivery during fetal surgery after maternal and/or fetal complications during the last 5 years were reported across 3 centers. Fewer than half the 28 centers (n = 12 [43%]) had policies in place to support practice in the event of either imminent fetal death (during or after fetal surgery) or the need for emergency fetal delivery during fetal surgery. Twenty of 24 centers (83%) reported preoperative parental counseling on the potential need for fetal resuscitation prior to fetal surgery. The gestational age at which centers would attempt neonatal resuscitation after emergency delivery varied from 22 weeks and 0 days to more than 28 weeks. Conclusions: In this global survey study of 28 fetal surgical centers, there was no standard practice about how fetal resuscitation or subsequent neonatal resuscitation was managed during open spina bifida repair. Further collaboration between professionals and parents is required to ensure sharing of information to support knowledge development in this area.

Expert ultrasonographic evaluation in fetuses with spina bifida: An essential prerequisite to select candidate to fetal surgery.

Suggested management flowchart in presence of a prenatal diagnosis of open spina bifida.

Training model for the fetal myelomeningocele correction with multiportal endoscopic technique.

PURPOSE: The recent history of myelomeningocele has shown that treatment during the fetal life may reduce the risk of developing hydrocephalus in individuals by approximately 50%. Thus, a significant advancement involves fetal surgery performed through an endoscopic technique in which portals are placed to introduce the forceps and laparoscopic instruments. However, the development of this technique requires training; therefore, this study aimed to develop a training model for fetal myelomeningocele repair technique with multi-portal endoscopy. METHODS: Two stages of endoscopic technique development were performed. The first stage consisted of exercises in order to familiarize the surgeon with 2D-vision endoscopic surgery, associated with the application of exercises focused on surgical skills, such as the development of laparoscopic knots in a synthetic model. The second stage involved the creation and application of the stages of myelomeningocele closure with a non-living animal model consisting of a chicken breast to simulate the myelomeningocele and a basketball to simulate the gravid uterus, in which perforations were made to introduce vascular introducers (portals) that, as in vivo, are used as portals (trocars) for the introduction of laparoscopic instruments. Overall, two different scenarios with three portals and two portals were tested. RESULTS: In three-portal simulator, the triangular apex trocar was used for the introduction of 4-mm 0° or 30° optics or even Minop type neurodoscope (Aesculap®, Germany) that was operated by the assistant surgeon; the other two portals are used for the introduction of laparoscopic instruments. Thus, the surgeon is able to perform maneuvers bimanually since dissection to laparoscopic sutures. In two-portal simulator, the surgeon and assistant stay side by side and one of the portals is used for the optic and the other for the laparoscopic instruments. There is no possibility of bimanual dissection in this method. CONCLUSION: Realistic simulation models for endoscopic fetal surgery for myelomeningocele correction are easily performed and help develop the necessary skills for fetal surgery teams.

Fetal Endoscopic Third Ventriculostomy Is Technically Feasible in Prenatally Induced Hydrocephalus Ovine Model.

BACKGROUND: Congenital obstructive hydrocephalus generates progressive irreversible fetal brain damage by ventricular enlargement and incremental brain tissue compression that leads to maldevelopment and poor clinical outcomes. Intrauterine treatments such as ventriculo-amniotic shunting have been unsuccessfully tried in the eighties. OBJECTIVE: To assess if prenatal endoscopic third ventriculostomy (ETV) is feasible in a large animal model and optimize this technique for ventricular decompression and potential arrest of fetal brain damage in fetal lambs. METHODS: We generated hydrocephalus in 50 fetal lambs by injecting a polymeric agent into the cisterna magna at midgestation (E85). Subsequently, 3 weeks later (E105), fetal ETV was performed using a small rigid fetoscope. The endoscopy entry point was located anterior to the coronal suture, 7 mm from the midline. RESULTS: We obtained clear visualization of the enlarged lateral ventricles by endoscopy in the hydrocephalic fetal lambs. The floor of the third ventricle was bluntly perforated and passed with the scope for a successful ETV. Total success was achieved in 32/50 cases (64%). Causes of failure were blurred vision or third ventricle obliteration by BioGlue in 10/50 (20%) cases, anatomic misdirection of the endoscope in 5 (10%) cases, 2 cases of very narrow foramen of Monro, and 1 case of choroid plexus bleeding. If we exclude the cases artificially blocked by the polymer, we had a successful performance of prenatal-ETV in 80% (32/40) of hydrocephalic fetuses. CONCLUSION: Despite the inherent difficulties arising from ovine brain anatomy, this study shows that innovative fetal ETV is technically feasible in hydrocephalic fetal lambs.

Fetal surgery is not associated with increased inflammatory placental pathology.

OBJECTIVE: Fetal surgery has improved neonatal outcomes; however, it is unknown if the intervention contributes to the developmental of inflammatory pathologies in the placenta. Here, an association between fetal surgery and placental pathology was examined. METHOD: This case-control study compared pregnancies with fetal surgery (n = 22), pregnancies with an indication for fetal surgery but without an intervention being done (n = 13), and gestational-age and fetus-number matched controls (n = 36). Data on maternal, infant, and placental outcomes were abstracted. Additionally, immunohistochemistry identified expression of lymphoid and myeloid cells in the placenta on a subset of cases. Comparisons were performed using Kruskal-Wallis or Pearson's chi-squared tests. RESULTS: Maternal characteristics were comparable between groups. Most fetal interventions were for diaphragmatic hernia, spina bifida, or twin-to-twin transfusion syndrome. Fetuses who were operated on before birth were more likely to be born preterm (p = 0.02). There was no increase in the rate of observed placental pathologies or immune cell infiltration in fetal surgery cases compared to controls. CONCLUSION: The data suggest that fetal surgery is not associated with increased inflammatory or morphologic pathology in the placenta. This observation supports the growing field of fetal surgery.

Local host response of commercially available dural patches for fetal repair of spina bifida aperta in rabbit model.

OBJECTIVE: Fetal surgery for spina bifida aperta (SBA) by open hysterotomy typically repairs anatomical native tissue in layers. Increasingly, fetoscopic repair is performed using a dural patch followed by skin closure. We studied the host response to selected commercially available patches currently being used in a fetal rabbit model for spina bifida repair. METHODS: SBA was surgically induced at 23-24 days of gestation (term = 31 days). Fetal rabbits were assigned to unrepaired (SBA group), or immediate repair with Duragen™ or Durepair™. Non-operated littermates served as normal controls. At term, spinal cords underwent immunohistochemical staining including Nissl and glial fibrillary acidic protein. We hypothesized that spinal cord coverage with a dural patch and skin closure would preserve motor neuron density within the non-inferiority limit of 201.65 cells/mm2 and reduce inflammation compared to unrepaired SBA fetuses. RESULTS: Motor neuron density assessed by Nissl staining was conserved both by Duragen (n = 6, 89.5; 95% CI -158.3 to -20.6) and Durepair (n = 6, 37.0; 95% CI -132.6 to -58.5), whereas density of GFAP-positive cells to quantify inflammation was lower than in unrepaired SBA-fetuses (SBA 2366.0 ± 669.7 cells/mm2 vs. Duragen 1274.0 ± 157.2 cells/mm2 ; p = 0.0002, Durepair 1069.0 ± 270.7 cells/mm2 ; p < 0.0001). CONCLUSIONS: Covering the rabbit spinal cord with either Duragen or Durepair followed by skin closure preserves motor neuron density and reduces the inflammatory response.

Minimally Invasive Fetal Surgery and the Next Frontier.

Most patients with congenital anomalies do not require prenatal intervention. Furthermore, many congenital anomalies requiring surgical intervention are treated adequately after birth. However, there is a subset of patients with congenital anomalies who will die before birth, shortly after birth, or experience severe postnatal complications without fetal surgery. Fetal surgery is unique in that an operation is performed on the fetus as well as the pregnant woman who does not receive any direct benefit from the surgery but rather lends herself to risks, such as hemorrhage, abruption, and preterm labor. The maternal risks involved with fetal surgery have limited the extent to which fetal interventions may be performed but have, in turn, led to technical innovations that have significantly advanced the field. This review will examine congenital abnormalities that can be treated with minimally invasive fetal surgery and introduce the next frontier of prenatal management of fetal surgical pathology.