Thoracoamniotic shunts for the management of fetal lung lesions and pleural effusions: a single-institution review and predictors of survival in 75 cases

Prenatal Management and Perinatal Outcome in a Large Series of Hydrops Fetalis

INTRODUCTION

Nonimmune hydrops fetalis (NIHF) is the most frequent etiology of hydrops fetalis (HF), accounting for around 95% of cases. It associates high perinatal mortality and morbidity rates. The aim of the study was, first, to investigate etiology, prenatal management, and perinatal outcome in a large single-center series of HF; second, to identify prenatal prognostic factors with impact on perinatal outcome.

MATERIALS AND METHODS

Observational retrospective study of 80 HF diagnosed or referred to a single tertiary center between 2012 and 2021. Clinical characteristics, etiology, prenatal management, and perinatal outcome were recorded. Adverse perinatal outcome was defined as intrauterine fetal death (IUFD), early neonatal death (first 7 days of life) and late neonatal death (between 7 and 28 days).

RESULTS

Seventy-six of the 80 cases (95%) were NIHF, main etiology being genetic disorders (28/76; 36.8%). A total of 26 women (32.5%) opted for termination of pregnancy, all of them in the NIHF group. IUFD occurred in 24 of 54 patients (44.4%) who decided to continue the pregnancy. Intrauterine treatment was performed in 29 cases (53.7%). There were 30 newborns (55.6%). Adverse perinatal outcome rate was 53.7% (29/54), significantly higher in those diagnosed <20 weeks of gestation (82.4% < 20 weeks vs. 40.5% ≥ 20 weeks; p = 0.004). Survival rate was higher when fetal therapy was performed compared to the expectantly managed group (58.6% vs. 32%; p = 0.05). Intrauterine blood transfusion and thoraco-amniotic shunt were the procedures that achieved the highest survival rates (88.9% and 100%, respectively, p = 0.003).

CONCLUSION

NIHF represented 95% of HF with genetic disorders as the main etiology. Most of them were diagnosed before 20 weeks of gestation, with worse prognosis than cases detected later in gestation. Rates of TOP, IUFD, and early neonatal death were higher in NIHF. Intrauterine therapy, when indicated, improved the perinatal outcome.

Fetal gene therapy

Fetal gene therapy was first proposed toward the end of the 1990s when the field of gene therapy was, to quote the Gartner hype cycle, at its "peak of inflated expectations." Gene therapy was still an immature field but over the ensuing decade, it matured and is now a clinical and market reality. The trajectory of treatment for several genetic diseases is toward earlier intervention. The ability, capacity, and the will to diagnose genetic disease early-in utero-improves day by day. A confluence of clinical trials now signposts a trajectory toward fetal gene therapy. In this review, we recount the history of fetal gene therapy in the context of the broader field, discuss advances in fetal surgery and diagnosis, and explore the full ambit of preclinical gene therapy for inherited metabolic disease.

Prenatally Diagnosed Large Lung Lesions: Timing of Resection and Perinatal Outcomes

INTRODUCTION

Fetuses with large lung lesions including congenital cystic adenomatoid malformations (CCAMs) are at risk for cardiopulmonary compromise. Prenatal maternal betamethasone and cyst drainage for micro- and macrocystic lesions respectively have improved outcomes yet some lesions remain large and require resection before birth (open fetal surgery, OFS), at delivery via an Ex Utero Intrapartum Treatment (EXIT), or immediately post cesarean section (section-to-resection, STR). We sought to compare prenatal characteristics and outcomes in fetuses undergoing OFS, EXIT, or STR to inform decision-making and prenatal counseling.

METHODS

A single institution retrospective review was conducted evaluating patients undergoing OFS, EXIT, or STR for prenatally diagnosed lung lesions from 2000 to 2021. Specimens were reviewed by an anatomic pathologist. Lesions were divided into "CCAMs" (the largest pathology group) and "all lung lesions" since pathologic diagnosis is not possible during prenatal evaluation when care decisions are made. Prenatal variables included initial, greatest, and final CCAM volume-ratio (CVR), betamethasone use/frequency, cyst drainage, and the presence of hydrops. Outcomes included survival, ECMO utilization, NICU length of stay (LOS), postnatal nitric oxide use, and ventilator days.

RESULTS

Sixty-nine percent (59 of 85 patients) of lung lesions undergoing resection were CCAMs. Among patients with pathologic diagnosis of CCAM, the initial, largest, and final CVRs were greatest in OFS followed by EXIT and STR patients. Similarly, the incidence of hydrops was significantly greater and the rate of hydrops resolution was lower in the OFS group. Although the rate of cyst drainage did not differ between groups, maternal betamethasone use varied significantly (OFS 60.0%, EXIT 100.0%, STR 74.3%; p = 0.0378). Notably, all OFS took place prior to 2014. There was no difference in survival, ventilator days, nitric oxide, NICU LOS, or ECMO between groups. In multiple variable logistic modeling, determinants of survival to NICU discharge among patients undergoing resection with a pathologic diagnosis of CCAM included initial CVR <3.5 and need for <3 maternal betamethasone doses.

CONCLUSION

For CCAMs that remain large despite maternal betamethasone or cyst drainage, surgical resection via OFS, EXIT, or STR are viable options with favorable and comparable survival between groups. In the modern era there has been a shift from OFS and EXIT procedures to STR for fetuses with persistently large lung lesions. This shift has been fueled by the increased use of maternal betamethasone and introduction of a Special Delivery Unit during the study period and the appreciation of similar fetal and neonatal outcomes for STR vs. EXIT and OFS with reduced maternal morbidity associated with a STR. Accordingly, efforts to optimize multidisciplinary perinatal care for fetuses with large lung lesions are important to inform patient selection criteria and promote STR as the preferred surgical approach in the modern era.

LEVEL OF EVIDENCE

Level IV.

Management dilemma in Thoracoamniotic Shunt Migrations

Shunt migration is a rare but significant complication of thoracoamniotic shunting, an intervention widely used for fetal pleural effusion. We describe a case of a term infant noted antenatally to have fetal hydrothorax that was managed with thoracoamniotic shunting but complicated by shunt migration. We also present the current literature on risk factors, complications and management of intrathoracic shunt migration. The majority of shunt migration cases are managed conservatively with no untoward postnatal sequelae, but surgical removal of the migrated shunt has been used for associated clinical complications, if visceral damage is suspected or if postnatal thoracic surgery is indicated for other reasons. We advocate an approach of conservative management for asymptomatic infants, where possible, to avoid unnecessary surgical and anaesthetic risks to very young, often already compromised children. However, further studies are still required to determine optimal management after shunt migration has occurred to ensure the best outcome.

Case report: Minimally invasive removal of a dislodged thoracoamniotic shunt with an integral cystoscope in a preterm infant

Introduction

Fetal pleural effusion is a rare condition that is associated with significant mortality. Although the insertion of fetal thoracoamniotic shunts can improve perinatal outcomes, there are several associated complications, such as intrathoracic dislodgement of the shunts. The optimal neonatal treatment for retained shunts remains uncertain.

Case Description

A male infant was born at 32 weeks of gestation. He had antenatal hydrothorax that was detected at 27 weeks of gestation and was managed by intrauterine thoracoamniotic shunting. However, the shunt catheter dislodged into the fetal chest, which caused reaccumulated pleural effusion and respiratory distress requiring ventilatory support after birth. After the patient's condition stabilized, minimally invasive removal of the retained catheter was performed on day 17 of life using an integral pediatric cystoscope via a 3-mm thoracic incision. The procedure took approximately 5 min. The postoperative course was uneventful, and the patient, who was discharged 39 days postnatally, is thriving at the 6-month follow-up.

Conclusions

We present a novel and effective approach to the management of an intrathoracic shunt using an integral cystoscope. This approach may offer a valuable alternative to traditional thoracoscopy in the neonatal period.

Morphologic Features in Congenital Pulmonary Airway Malformations and Pulmonary Sequestrations Correlate With Mutation Status: A Mechanistic Approach to Classification

Congenital pulmonary airway malformations (CPAMs) have a range of morphologies with varying cyst sizes and histologic features (types 1 to 3). Evidence suggested they arise secondary to bronchial atresia, however, we recently showed that cases with type 1 and 3 morphology are driven by mosaic KRAS mutations. We hypothesized that 2 distinct mechanisms account for most CPAMs: one subset is secondary to KRAS mosaicism and another is due to bronchial atresia. Cases with type 2 histology, similar to sequestrations, would be related to obstruction and therefore negative for KRAS mutations regardless of cyst size. We sequenced KRAS exon 2 in type 2 CPAMs, cystic intralobar and extralobar sequestrations, and intrapulmonary bronchogenic cysts. All were negative. Most sequestrations had a large airway in the subpleural parenchyma adjacent to the systemic vessel, anatomically confirming bronchial obstruction. We compared morphology to type 1 and 3 CPAMs. On average, type 1 CPAMs had significantly larger cysts, but there remained substantial size overlap between KRAS mutant and wild-type lesions. Features of mucostasis were frequent in sequestrations and type 2 CPAMs, while their cysts were generally simple and round with flat epithelium. Features of cyst architectural and epithelial complexity were more common in type 1 and 3 CPAMs, which rarely showed mucostasis. Similarity in histologic features among cases that are negative for KRAS mutation support the hypothesis that, like sequestrations, the malformation of type 2 CPAMs is related to obstruction during development. A mechanistic approach to classification may improve existing subjective morphologic methods.

The long-term outcome following thoraco-amniotic shunting for congenital lung malformations

AIM OF THE STUDY

Insertion of a thoraco amniotic shunt (TAS) during fetal life is a therapeutic option where there is a high risk of death secondary to large congenital lung malformations (CLM). The aim of this study is to present our center's long-term experience.

METHODS

Retrospective single center review of the period (Jan 2000-Dec 2020). We included all fetuses that underwent TAS insertion for CLM with detailed analysis of those live newborns managed in our center. Data are quoted as median (range).

MAIN RESULTS

Thirty one fetuses underwent 37 TAS insertions at a 25 (20-30) weeks gestational age. This was successful on 1st attempt in 30 (97%) fetuses. In 6 cases a 2nd shunt was required at 6.5 (2-10) weeks following the 1st insertion. Twenty-eight survived to be born. Sixteen (9 male) infants were delivered in our center at 39 (36-41) weeks gestational age and birth weight of 3.1 (2.6-4.2) kg. All infants underwent surgery at 2 (0-535) days (emergency surgery, n = 9; expedited n = 4; elective surgery, n = 3). Final histopathology findings were CPAM Type 1 (n = 14, n.b. associated with mucinous adenocarcinoma, n = 1), CPAM Type 2 (n = 1) and an extralobar sequestration (n = 1). Postoperative stay was 16 (1-70) days with survival in 15/16 (94%). One infant died at 1 day of life secondary to a combination of pulmonary hypoplasia and hypertension. Median follow up period was 10.7 (0.4-20.4) years. Nine (60%) children developed a degree of chest wall deformity though none have required surgical intervention. Clinically, 14/15 (93%) have otherwise normal lung function without limitations of activity, sporting or otherwise. One child has a modest exercise limitation (FVC - 70% predicted).

CONCLUSIONS

TAS insertion is associated with high perinatal survival and should be considered in fetuses at risk of hydrops secondary to large cystic lung malformation. Their long term outcome is excellent although most have a mild degree of chest wall deformity.

Combined Pre- and Postnatal Minimally Invasive Approach to a Complex Symptomatic Congenital Pulmonary Airway Malformation

Congenital pulmonary airway malformation (CPAM) is a rare congenital lung lesion that usually remains asymptomatic during the fetal and neonatal period. However, it can occasionally cause prenatal cardiocirculatory failure and fetal hydrops, requiring a thoraco-amniotic shunt (TAS) placement. In other cases, it can also cause symptoms at birth (such as respiratory distress) and may require urgent surgical intervention. Thoracoscopic lobectomy for neonates is rarely reported. Here, we report a case of right macrocystic CPAM causing fetal hydrops at 27 weeks of gestation. The fetus was treated with a TAS placement that successfully resolved the hydrops. At 39 weeks of gestation, a male neonate was born (weight 2,850 g). The TAS spontaneously displaced during delivery, causing an open pneumothorax (PNX), initially treated with a drainage. His condition gradually worsened, requiring ventilatory support. Computed tomography (CT) scan showed different giant cysts in the context of the right lower lobe, left mediastinal shift, and compression of the rest of the lung. An urgent surgical management was required. A thoracoscopic right lower lobectomy was performed at 10 days of life (weight 2,840 g). The postoperative course was uneventful; the child remained totally asymptomatic and showed a good recovery. To the best of our knowledge, this is the first reported case of open iatrogenic PNX following TAS positioning and the second of neonatal thoracoscopic lobectomy in a newborn weighting less than 3 kg. The purpose of this report is to indicate that minimally invasive surgery is feasible, safe, and effective for the resection of CPAM, even in small newborns.

The natural history of prenatally diagnosed congenital pulmonary airway malformations and bronchopulmonary sequestrations

BACKGROUND

The natural history of congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestrations (BPS) is not fully understood, and the management of the newborn with an asymptomatic lesion is a controversial issue. We aimed to study the natural history and outcome of CPAM/BPS at our institution with a policy of watchful waiting, and to investigate if any prognostic factors in the pre- and/or postnatal- period may predict the need for surgery.

MATERIAL AND METHODS

A retrospective review study was conducted of children prenatally diagnosed with CPAM and/or BPS during the 18-year period, from 2002 to 2020. Data from the pre and postnatal period was collected and analysed.

RESULTS

Sixty- six patients with prenatally observed lung lesions were entered in the study, with an overall survival rate of 94%. Fifty-six percent of the lesions decreased in size during gestation. Thirty-one percent had surgery and 69% could be managed conservatively with a median follow-up of 4 years. Nineteen percent developed symptoms after the neonatal period. Children with a presence of mediastinal shift on postnatal imaging (p = 0.003), with a high CVR (p = 0.005) and a large lesion size during gestation (p = 0.014) were significantly more likely to require surgery.

CONCLUSION

Prenatal regression is common among prenatally diagnosed CPAM/BPS and the majority of children that are asymptomatic beyond the neonatal period will remain asymptomatic throughout their childhood. Future analysis with a longer follow-up might give new insights in order to identify children at risk of developing symptoms.

LEVEL OF EVIDENCE

III.

Care Levels for Fetal Therapy Centers

Fetal therapies undertaken to improve fetal outcome or to optimize transition to neonate life often entail some level of maternal, fetal, or neonatal risk. A fetal therapy center needs access to resources to carry out such therapies and to manage maternal, fetal, and neonatal complications that might arise, either related to the therapy per se or as part of the underlying fetal or maternal condition. Accordingly, a fetal therapy center requires a dedicated operational infrastructure and necessary resources to allow for appropriate oversight and monitoring of clinical performance and to facilitate multidisciplinary collaboration between the relevant specialties. Three care levels for fetal therapy centers are proposed to match the anticipated care complexity, with appropriate resources to achieve an optimal outcome at an institutional and regional level. A level I fetal therapy center should be capable of offering fetal interventions that may be associated with obstetric risks of preterm birth or membrane rupture but that would be very unlikely to require maternal medical subspecialty or intensive care, with neonatal risks not exceeding those of moderate prematurity. A level II center should have the incremental capacity to provide maternal intensive care and to manage extreme neonatal prematurity. A level III therapy center should offer the full range of fetal interventions (including open fetal surgery) and be able manage any of the associated maternal complications and comorbidities, as well as have access to neonatal and pediatric surgical intervention including indicated surgery for neonates with congenital anomalies.

In-utero treatment of prenatal thoracic abnormalities by thoraco-amniotic shunts, short and long term neuro developmental outcome: A single center experience

BACKGROUND

Severe primary fetal hydrothorax (PFH) and fetal lung lesions (FLL) such as congenital pulmonary airway malformation (CPAM) and Bronchopulmonary sequestration (BPS) are often treated by thoraco-amniotic shunt (TAS).

OBJECTIVES

To compare short and long-term outcome of fetuses treated by TAS due to FLL to those treated due to PFH.

METHOD

A retrospective analysis was performed for all fetuses treated by TAS, between the years 2004-2015, evaluating the short and long term neurodevelopmental outcome. Long term neurodevelopment was additionally analyzed prospectively by Vineland adaptive behavioral scale (VABS) standardized questionnaires.

RESULTS

38 fetuses were treated by 52 TAS insertions; of which 13 (35%) due to FLL and 25 due to PFH. Perinatal survival was high (87.9%) with 3 neonatal death and one termination of pregnancy (TOP). High survival rate persisted even in cases requiring recurrent shunt insertion (80% survival). There was no significant difference in short or long term outcome including perinatal survival (84% Vs 90%, P = 0.64) and hydrops resolution (91% Vs 63%, p = 0.19). Long term outcome, including rate of neurodevelopmental abnormalities (23.5% Vs 20%) and VABS score (91.3 ± 13.3 Vs 96.4 ± 14.7), were similar for both groups.

CONCLUSION

TAS insertion is effective and resulting in high perinatal survival even in cases when sequential insertion is needed. Short and long- term outcome of neonates with FLL treated by TAS are comparable to neonates treated due to PFH.

Maternal Fetal Surgery: Intervention and Management

Congenital malformations occur in about 3% of all live births and are a leading cause of perinatal morbidity and mortality. An evolving understanding of the developing human fetus, advances in imaging, availability of cutting-edge instrumentation, and enhanced understanding of fetal pathophysiology, have allowed for prenatal surgical interventions to improve fetal diseases and neonatal outcomes. Fetal surgical therapy is no longer restricted to life-threatening prenatal diagnoses and can be categorized into either open surgical techniques or minimally invasive endoscopic/ultrasound-guided techniques. Patient selection requires a thorough multidisciplinary evaluation and shared decision-making process.

Perinatal Outcome in Fetuses with Dislodged Thoraco-Amniotic Shunts

OBJECTIVE

Fetal thoraco-amniotic shunts (TASs) can dislodge in utero, migrating internally into the fetal thorax or externally into the amniotic cavity. Our objective was to evaluate the perinatal and long-term outcome of fetuses with TAS dislodgement and conduct a review of the literature.

METHODS

This is a retrospective review of all TAS inserted for primary pleural effusions and macrocystic congenital pulmonary airway malformations (CPAMs) in a tertiary fetal medicine center (1991-2020). Antenatal history, procedural factors, and perinatal and long-term outcomes were reviewed in all fetuses with dislodged shunts and compared to fetuses with shunts that did not dislodge.

RESULTS

Of 211 TAS inserted at a mean gestational age of 27.8 weeks ± 5.47 (17.4-38.1 weeks), 187 (89%) were inserted for pleural effusions and 24 (11%) for macrocystic CPAMs. Shunts dislodged in 18 fetuses (8.5%), 17 (94%) of which were for pleural effusions. Shunts migrated into the chest wall/amniotic cavity or into the thorax among 7/18 (39%) and 11/18 (61%) fetuses, respectively. Eleven (61%) fetuses were initially hydropic, which resolved in 8 (72%) cases. Effusions were bilateral in 9 (50%), amnioreduction was required in 6 (33%), and fetal rotation in 8 cases (44%). Four (22%) fetuses underwent repeat shunting, 12 (67%) neonates required ventilatory support, and 2 (11%) neonates required chest tubes. There was no significant difference in technical factors or outcomes between infants with shunts that dislodged and those that did not. Among 11 intrathoracic shunts, 2 (18%) were removed postnatally and the remainder are in situ without any shunt-related or respiratory complications over a follow-up period of 9 months to 22 years.

CONCLUSION

TAS dislodged antenatally in 8.5% of fetuses, with 2/3 of shunts migrating into the thorax, and nearly 25% requiring re-shunting. Retained intrathoracic shunts were well tolerated and may not necessarily require surgical removal after birth.

Fetal surgery

Fetal medicine is a super-specialty enterprise and a technology-driven field. The growth and interest in fetal surgery can be largely attributed to advances in fetal imaging and bespoke instruments for in utero intervention. Previously fatal fetal conditions are now being treated using open surgery, minimally invasive procedures, and percutaneous fetal technologies. Several fetal conditions, including myelomeningocele and twin-to-twin transfusion syndrome, have been tested rigorously in RCTs. However, as the specialty of fetal surgery grows, a robust evidence base with long-term follow-up is obligatory for every procedure. This article offers an overview of fetal surgery and antenatal intervention. As more cutting edge therapies come into clinical practice, growing public opinion and medical ethics will play a significant role in the future of this multidisciplinary specialty.

Intrathoracic shunt displacement with massive pleural effusion after successful shunt placement in a hydropic fetus with multilocular macrocystic congenital pulmonary airway malformation

We successfully performed shunting for a fetus with a multilocular macrocystic lung mass with hydrops at 22 weeks' gestation. Complete resolution of hydrops was achieved; however, at 35 weeks' gestation, the fetus developed acute massive pleural effusion. Fetal ultrasound examination revealed that one end of the shunting tube had migrated downward in the thoracic cavity, which led to fluid draining from the lung cyst. The baby was delivered at term and was discharged following neonatal intensive care management. Intrathoracic displacement of the shunt can occur, followed by massive pleural effusion due to drainage of cystic fluid.

Sorting pain out of salience: assessment of pain facial expressions in the human fetus

Supplemental Digital Content is Available in the Text.

Acute pain facial expressions can be detected/scored in human fetuses. We propose a seven-item scale to differentiate pain facial expressions from rest/acoustic stimuli ones.

Introduction:

The question of whether the human fetus experiences pain has received substantial attention in recent times. With the advent of high-definition 4-dimensional ultrasound (4D-US), it is possible to record fetal body and facial expressions.

Objective:

To determine whether human fetuses demonstrate discriminative acute behavioral responses to nociceptive input.

Methods:

This cross-sectional study included 5 fetuses with diaphragmatic hernia with indication of intrauterine surgery (fetoscopic endoluminal tracheal occlusion) and 8 healthy fetuses, who were scanned with 4D-US in 1 of 3 conditions: (1) acute pain group: Fetuses undergoing intrauterine surgery were assessed in the preoperative period during the anesthetic injection into the thigh; (2) control group at rest: Facial expressions at rest were recorded during scheduled ultrasound examinations; and (3) control group acoustic startle: Fetal facial expressions were recorded during acoustic stimulus (500–4000 Hz; 60–115 dB).

Results:

Raters blinded to the fetuses’ groups scored 65 pictures of fetal facial expressions based on the presence of 12 items (facial movements). Analyses of redundancy and usefulness excluded 5 items for being of low discrimination capacity (P>0.2). The final version of the pain assessment tool consisted of a total of 7 items: brow lowering/eyes squeezed shut/deepening of the nasolabial furrow/open lips/horizontal mouth stretch/vertical mouth stretch/neck deflection. Odd ratios for a facial expression to be detected in acute pain compared with control conditions ranged from 11 (neck deflection) to 1,400 (horizontal mouth stretch). Using the seven-item final tool, we showed that 5 is the cutoff value discriminating pain from nonpainful startle and rest.

Conclusions:

This study inaugurates the possibility to study pain responses during the intrauterine life, which may have implications for the postoperative management of pain after intrauterine surgical interventions

ATS Core Curriculum 2020. Pediatric Pulmonary Medicine

The American Thoracic Society Core Curriculum updates clinicians annually in adult and pediatric pulmonary disease, medical critical care, and sleep medicine, in a 3- to 4-year recurring cycle of topics. These topics will be presented at the 2020 International Conference. Below is the pediatric pulmonary medicine core, including pediatric hypoxemic respiratory failure; modalities in noninvasive management of chronic respiratory failure in childhood; surgical and nonsurgical management of congenital lung malformations; an update on smoke inhalation lung injury; an update on vaporizers, e-cigarettes, and other electronic delivery systems; pulmonary complications of sarcoidosis; pulmonary complications of congenital heart disease; and updates on the management of congenital diaphragmatic hernia.

Foetal therapies and their influence on preterm birth

Foetal therapy aims to improve perinatal survival or to prevent severe long-term handicap. Foetal medicine opens a new territory by treating the foetus as a patient. The mother has nothing to gain in terms of health benefits, yet she is inherently also undergoing treatment. In utero foetal interventions can be divided into ultrasound-guided minimally invasive procedures, fetoscopic procedures and open hysterotomy procedures, which carry an inherent risk of ruptured membranes and preterm birth. In this review, we summarise the conditions that may benefit from foetal therapy and review the current therapies on offer, each with their associated risk of ruptured membrane and preterm birth. We also look into some risk limiting and preventative strategies to mitigate these complications.

New Trends in Fetal Anesthesia

Fetal anesthesia teams must understand the pathophysiology and rationale for the treatment of each disease process. Treatment can range from minimally invasive procedures to maternal laparotomy, hysterotomy, and major fetal surgery. Timing may be in early, mid-, or late gestation. Techniques continue to be refined, and the anesthetic plans must evolve to meet the needs of the procedures. Anesthetic plans range from moderate sedation to general anesthesia that includes monitoring of 2 patients simultaneously, fluid restriction, invasive blood pressure monitoring, vasopressor administration, and advanced medication choices to optimize fetal cardiac function.

Anesthesia for Fetal Surgery and Fetal Procedures

Advances in imaging and technique have pushed the boundaries of the types of surgical interventions available to fetuses with congenital and developmental abnormalities. This review focuses on fundamental aspects of fetal anesthesia, including the physiologic changes of pregnancy, uteroplacental perfusion, and fetal physiology. We discuss the types of fetal surgeries and procedures currently being performed and discuss the specific anesthetic approaches to different categories of fetal surgeries. We also discuss ethical aspects of fetal surgery and anesthesia.

Congenital Cystic Lung Lesions: Redefining the Natural Distribution of Subtypes and Assessing the Risk of Malignancy

Asymptomatic cystic lung lesions-congenital pulmonary airway malformations (CPAMs), sequestrations, and bronchogenic cysts-are commonly diagnosed prenatally. Indications to resect are to eliminate risk of malignancy or infection. CPAMs consist of a spectrum of malformations, with type 1 historically considered the most common. Mucinous cell clusters, seen almost exclusively in type 1, are premalignant lesions at risk for progression to mucinous adenocarcinoma. We reviewed and classified 2.5 years of consecutive, prenatally diagnosed lesions as extralobar sequestration, intralobar sequestration, type 1 CPAM, type 2 CPAM/bronchial atresia, or "other" to determine the distribution of lesion types and risk of malignancy. One hundred eighty-four lesions in 174 patients showed type 1 CPAM to be least common subtype. Type 1 CPAMs had more severe presentation, infrequently had features of obstruction, and usually had cysts ≥2 cm. Fifteen of eighteen type 1 CPAMs had mucinous cell clusters (total risk, 8%), with mucous cells outside main cyst in 12/15. No pleuropulmonary blastomas were identified. Additional historic cases were reviewed to further evaluate risk of malignancy. Over 14 years, 28 infants with fetal/type 1 lesions were identified, with clusters of mucinous cells in 75% of cases. A total of 9 pleuropulmonary blastomas were diagnosed in 6 patients over 16 years. Contrary to historical studies, type 1 CPAMs are much less common than type 2, likely related to detection of asymptomatic lesions prenatally. A majority of type 1 CPAMs contain mucinous cell clusters. This data is useful in management of patients in centers that do not resect asymptomatic lesions.

The Utility of the Congenital Pulmonary Airway Malformation-Volume Ratio in the Assessment of Fetal Echogenic Lung Lesions: A Systematic Review

Although relatively uncommon, the incidence of fetal echogenic lung lesions - a heterogeneous group of anomalies that includes congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestrations (BPS) - has increased recently. Two decades ago, the CPAM-volume ratio (CVR) was first described as a tool to predict the development of hydrops, with this outcome found to be unlikely in fetuses with CVRs of ≤1.6 cm2. Since then, no clear international consensus has evolved as to the optimal CVR thresholds for the prediction of fetal/neonatal outcomes. This systematic review aimed to assess all original research studies that reported on the predictive utility of the CVR. Potentially relevant papers were identified through searching for citations of the paper that originally described the CVR, in addition to keyword searches of electronic databases. Fifty-two original research papers were included in the final review. Of these, 34 used the CVR for descriptive purposes only, 5 assessed the validity of established thresholds in different populations, and 13 proposed new thresholds. The evidence identified in this review would suggest that a threshold much lower than 1.6 cm2 is likely to be of greater utility in most populations for many outcomes of perinatal relevance. For neonatal outcomes (mostly respiratory compromise at birth), a CVR on the initial ultrasound scan ranging from 0.5 to 1.0 cm2 appears to have the greatest predictive value. Although a number of studies concurred that 1.6 cm2 was a useful threshold for the prediction of hydrops, many others were unable to assess this due to the rarity of this complication. For this reason, thresholds as low as 0.4 cm2 may be more useful for the prediction of a broader range of fetal concerns, including mediastinal shift and fluid collections. Further large-scale studies are required to determine the true utility of this well-established index.

Management of fetal tumors

In this review article, we discuss the most common fetal tumors, their prenatal management, and outcomes. Overall, the most important outcome predictors are tumor histology, size, vascularity, and location. Very large lesions, lesions causing cardiac failure, and hydrops and lesions obstructing the fetal airway have the poorest outcome, as they may cause fetal death or complications at the time of delivery. Fetal therapy has been developed to improve outcomes for the most severe cases and can consist of transplacental therapy (sirolimus for rhabdomyomas or steroids for hemangiomas and microcystic lung lesions) or surgical intervention (shunting of cystic masses, tumor ablation, occlusion of blood flow or airway exploration, and protection). Given the rarity of fetal tumors, patients should be referred to expert centers where care can be optimized and individualized to allow the best possible outcomes.

Fetal primary pleural effusions: Prenatal diagnosis and management

Fetal pleural effusions can be associated with significant perinatal morbidity and mortality. When diagnosed antenatally, referral to a tertiary fetal medicine center is recommended for a detailed ultrasound evaluation for additional structural abnormalities or features suggestive of congenital infections or fetal anemia. The effusions should be characterized as unilateral or bilateral, and presence of hydrops and/or mediastinal shift should be documented. Additional testing should include fetal echocardiography, maternal testing for blood group and screen, hemoglobinopathies, and congenital infections. Invasive genetic testing is recommended with infectious testing on amniotic or pleural fluid. Pleuroamniotic shunting is recommended for large primary pleural effusions with significant mediastinal shift or hydrops, as several large series have demonstrated improvement in perinatal survival, particularly in hydropic fetuses. Delivery should occur in a tertiary care center with neonatal expertise, and infants should be followed up long-term for respiratory and neurodevelopmental outcomes.

Fetal intervention for congenital chylothorax is associated with improved outcomes in early life

BACKGROUND

Congenital chylothorax (CC) can have devastating consequences for neonates. We sought to determine the outcomes of cases treated at our institution and evaluate the role of fetal intervention.

MATERIALS AND METHODS

With Institutional Review Board approval, patients treated at our institution 09/2006-04/2016 with CC were reviewed. History and outcomes were compared between patients undergoing fetal intervention (fetal group) and patients who did not (control group).

RESULTS

Twenty-three patients were identified. Mean gestational age at birth was 35 wk. Overall mortality was 30% (7 patients). Nineteen patients (83%) were prenatally diagnosed, and 10 patients (43%) underwent fetal intervention. Birth weight was significantly lower in the fetal group compared to the control group (median interquartile range [IQR]; 2.5 [2.3-3.0] versus 3.3 [2.6-3.7] kg, P = 0.02). Apgar scores were significantly higher in the fetal group than the control group at 1 and 5 min (median [IQR]; 6 [4-8] versus 1 [1-2], P = 0.005 and 8 [7-9] versus 2 [2-6], P = 0.008, respectively). For those patients with prenatal diagnosis of CC and hydrops fetalis, thrombosis and lymphopenia were both improved in the fetal group (thrombosis 0% versus 40%, P = 0.03; lymphocyte nadir [median {IQR}] 1.5 [0.6-2.9] versus 0.1 [0.05-0.2], P = 0.02). Duration of support with mechanical ventilation was significantly shorter in the fetal group (median [IQR]; 1 [0-40] versus 41 [29-75] d, P = 0.04).

CONCLUSIONS

Fetal intervention for CC is associated with improved Apgar scores and decreased ventilator days and complications in patients with hydrops fetalis. Fetuses with chylothorax, especially those with hydrops, should be referred to a fetal center for evaluation.

Fetal lung size after thoracoamniotic shunting reflects survival in primary fetal hydrothorax with hydrops

AIM

To assess the role of lung size and abnormal Doppler findings in the umbilical artery (UA) in determining the outcomes of fetuses with primary fetal hydrothorax (FHT) associated with hydrops who underwent thoracoamniotic shunting (TAS).

METHODS

This was a retrospective study at a single center. We included cases of primary FHT with hydrops who underwent TAS at our hospital between 2004 and 2016. We assessed the relationship between mortality until 28 days after birth and ultrasound findings, including absent or reversed end-diastolic velocity (AREDV) in the UA and the lung-to-thorax transverse area ratio (LTR), before and after TAS.

RESULTS

Forty-one cases of primary FHT with hydrops underwent TAS. The median (range) gestational age at TAS was 28.5 (19.3-33.8) weeks. Bilateral pleural effusion was observed in 39 cases (95.1%). Among the 41 cases, 19 (46.4%) survived, 11 (26.8%) died in utero, and 11 (26.8%) died in the neonatal period. AREDV in the UA before and after TAS were not associated with mortality (P = 0.32 and 0.47, respectively). The odds ratio for mortality in LTR 0.2-0.3 before TAS was 0.62 (vs LTR < 0.2, P = 0.45) and that in LTR 0.2-0.3 and > 0.3 after TAS were 0.27 and 0.06, respectively (vs LTR < 0.2, P for trend <0.01).

CONCLUSION

A larger LTR after TAS was significantly associated with a better prognosis in hydropic primary FHT. The fetal lung size after the procedure may be a prognostic factor of primary FHT.

Short-Term Neurodevelopmental Outcome in Children Born With High-Risk Congenital Lung Lesions

BACKGROUND

This study sought to evaluate neurodevelopmental outcome in survivors of high-risk congenital lung lesions (CLLs) who underwent prenatal intervention or postnatal surgery within the first month of life.

METHODS

Forty-five high-risk CLL survivors underwent assessment using the Bayley Scales of Infant Development, 3rd Edition between July 2004 and December 2016. Scores were grouped as average, at-risk, and delayed based on SD intervals. Correlations between outcome and risk factors were analyzed by Fisher's exact test or two-sided t test as appropriate, with significant p values <0.05.

RESULTS

Open prenatal intervention was required in 13 (28.9%) children (fetal surgical resection, n = 4 , ex utero intrapartum treatment, n = 9), whereas 32 (71.1%) children had respiratory distress postnatally and required resection within the first month of life. Mean age at follow-up was 19.3 ± 10.3 months. Mean composite scores were within the expected average range. A total of 62.2% scored within the average range for all domains. At-risk scores were found in 26.7% of children in at least one domain, and 11.1% had delays in at least one domain. Neurodevelopmental outcome was similar between treatment groups. Prolonged ventilator support and neonatal intensive care unit stay, need for supplemental oxygen at day of life 30, gastroesophageal reflux disease, and delayed enteral feeding were associated with neurologic delays (all p < 0.05).

CONCLUSIONS

Neurodevelopmental scores for high-risk CLL survivors in infancy and toddlerhood are age appropriate. Neither fetal intervention nor the need for postnatal resection within the first month of life increases the risk of delays. Surrogate markers of a complicated neonatal course are predictive of adverse outcome.

Prenatal growth characteristics and pre/postnatal management of bronchopulmonary sequestrations

PURPOSE

The prenatal natural history of intralobar and extralobar bronchopulmonary sequestrations (BPSs), including lesion growth patterns and need for prenatal intervention, have not been fully characterized. We review our series of BPSs to determine their natural history and outcomes in the context of the need for prenatal intervention.

METHODS

A retrospective review of the pre/postnatal course of 103 fetuses with an intralobar (n=44) or extralobar BPS (n=59) managed at a single institution between 2008 and 2015 was performed. Outcomes included prenatal lesion growth trajectory, presence of hydrops, need for prenatal intervention, survival, and postnatal surgical management.

RESULTS

Most extralobar (71%) and intralobar BPSs (94%) decreased in size or became isoechoic from initial to final evaluation. Peak lesion size occurred at 26-28weeks gestation. Eight fetuses developed hydrothorax, four of which (all extralobar BPSs) also developed hydrops. All four hydropic fetuses received maternal betamethasone, and three hydropic fetuses underwent thoracentesis and/or thoracoamniotic shunt placement with subsequent hydrops resolution. All fetuses survived. Forty-one intralobar (93%) and 35 extralobar BPSs (59%) were resected after birth.

CONCLUSIONS

BPSs tend to decrease in size after 26-28weeks gestation and rarely require fetal intervention. Lesions resulting in hydrothorax ± hydrops can be effectively managed with maternal steroids and/or drainage of the hydrothorax.

LEVEL OF EVIDENCE

IV.

Shunt-based interventions: Why, how, and when to place a shunt

The broad categories of surgical fetal therapy can be separated into either open surgical techniques or minimally invasive endoscopic/ultrasound-guided techniques that require only puncture of the uterus with single or multiple small ports. Benefits of fetoscopic or ultrasound-guided fetal intervention include decreased uterine irritability, decreased incidence of preterm labor, and avoidance of risks associated with hysterotomy and commitment to cesarean delivery for future pregnancies. Fetal abnormalities potentially amenable to ultrasound-guided drainage techniques include thoracic fluid-filled lesions and lower urinary tract obstruction.

Minimally Invasive Fetal Surgery

Fetal surgery corrects severe congenital anomalies in utero to prevent their severe consequences on fetal development. The significant risk of open fetal operations to the pregnant mother has driven innovation toward minimally invasive procedures that decrease the risks inherent to hysterotomy. In this article, we discuss the basic principles of minimally invasive fetal surgery, the general history of its development, specific conditions and procedures used to treat them, and the future of the field.

Outcomes of fetuses with primary hydrothorax that undergo prenatal intervention (prenatal intervention for hydrothorax)

BACKGROUND

Primary hydrothorax is a congenital anomaly affecting 1 in 10,000-15,000 pregnancies. The natural history of this condition is variable with some fetuses having spontaneous resolution and others showing progression. The associated pulmonary hypoplasia leads to increased perinatal morbidity and mortality. Optimal prenatal intervention remains controversial.

METHODS

After obtaining the Institutional Review Board approval, a retrospective review of all patients evaluated for a fetal pleural effusion in the Fetal Diagnosis and Treatment Center at The University of Michigan, between 2006 and 2016 was performed. Cases with secondary etiologies for an effusion or when families decided to pursue elective termination were excluded.

RESULTS

Pleural effusions were identified in 175 patients. Primary hydrothorax was diagnosed in 15 patients (8%). The effusions were bilateral in 13/15 cases (86%) and 10/15 (66%) had hydrops at presentation. All 15 patients with primary hydrothorax underwent prenatal intervention. Thoracentesis was performed in 14/15 cases (93%). Shunt placement was performed in 10/15 cases (66%). Shunt migration was seen in four patients (40%) and all of these underwent prenatal shunt replacement. Overall survival was 76%. The rates of prematurity and preterm premature rupture of membranes were 69% and 35%, respectively.

CONCLUSIONS

Fetal intervention for the treatment of primary hydrothorax is effective, and it appears to confer a survival advantage. Both the fetuses and the mothers tolerated the procedures well. Preterm labor and preterm premature rupture of membranes remain an unsolved problem. Further studies are needed to understand the mechanisms behind the development of fetal hydrothorax.

Congenital chylothorax

Congenital chylothorax (CC) results from multiple lymphatic vessel anomalies or thoracic cavity defects and may accompany other congenital anomalies. Fetal chylothorax may increase the risk of death and complications from pleural space lymphatic fluid accumulation, which compromises lung development, pulmonary, and cardiovascular function and from complications arising from the loss of drained lymphatic contents. Prenatal interventions might improve survival in severe cases of fetal chylothorax. The neonatal treatment strategy is generally supportive with interventions that include thoracostomy drainage and attempts to decrease chyle flow using a stepwise approach that begins with the least invasive means. Evidence-based treatment choices are lacking and are much needed. Most cases of CC resolve with time even without specific lymphatic system studies to identify the exact pathology. Expertise in performing lymphatic studies is not universally available. Data on both efficacy and safety of the various therapeutic options are needed to determine the best approach to the treatment of CC.

[Congenital anomalies of poor prognosis. Genetics Consensus Committee]

INTRODUCTION

The Genetic Branch of the Chilean Society of Paediatrics, given the draft Law governing the decriminalisation of abortion on three grounds, focusing on the second ground, which considers the "embryo or foetus suffering from a congenital structural anomaly or a genetic disorder incompatible with life outside the womb", met to discuss the scientific evidence according to which congenital anomalies (CA) may be included in this draft law.

METHODOLOGY

Experts in clinical genetics focused on 10 CA, reviewed the literature evidence, and met to discuss it.

RESULTS

It was agreed not to use the term "incompatible with life outside the womb", as there are exceptions and longer survivals, and change to "congenital anomaly of poor prognosis (CAPP)". Ten CA were evaluated: serious defects of neural tube closure: anencephaly, iniencephaly and craniorachischisis, pulmonary hypoplasia, acardiac foetus, ectopia cordis, non-mosaic triploidy, "limb body wall" complex, "body stalk" anomaly, trisomy 13, trisomy 18, and bilateral renal agenesis. Findings on the prevalence, natural history, prenatal diagnostic methods, survival, and reported cases of prolonged survival were analysed. Post-natal survival, existence of treatments, and outcomes, as well as natural history without intervention, were taken into account in classifying a CA as a CAPP.

CONCLUSION

A CAPP would be: anencephaly, severe pulmonary hypoplasia, acardiac foetus, cervical ectopia cordis, non-mosaic triploidy, limb body wall complex, body stalk anomaly, non-mosaic trisomy 13, non-mosaic trisomy 18, and bilateral renal agenesis. For their diagnosis, it is required that all pregnant women have access to assessments by foetal anatomy ultrasound and occasionally MRI, and cytogenetic and molecular testing.

Refractory tension pneumothorax as a result of an internally displaced thoracoamniotic shunt in an infant with a congenital pulmonary airway malformation

Antenatally, congenital pulmonary airway malformation (CPAM) causing fetal hydrops can be palliated with thoracoamniotic shunts, which may become displaced in utero. We report a case of an infant born at 34 weeks gestational age with an antenatally diagnosed macrocystic lung lesion, fetal hydrops and an internally displaced thoracoamniotic shunt. The infant suffered refractory pneumothoraces despite multiple chest drains, and stabilised only after surgical resection of the lesion. Intraoperatively, the shunt was noted to form a connection between a type I CPAM and the pleural space. As the shunt was displaced internally, this complication was not immediately obvious during the initial resuscitation. In infants with large cystic lung lesions, clinicians should be aware that internally displaced thoracoamniotic shunts could contribute to refractory tension pneumothoraces and anticipate the need for advanced neonatal resuscitation, including early thoracocentesis or chest drain insertion. Furthermore, displaced shunts may require early surgical intervention.

Effect of single and multiple courses of maternal betamethasone on prenatal congenital lung lesion growth and fetal survival

PURPOSE

Administration of maternal betamethasone (BMZ) is a therapeutic option for fetuses with large microcystic congenital lung lesions at risk for, or causing, hydrops. Not all fetuses respond to a single course of BMZ. We review our experience with the use of single and multiple courses of maternal BMZ for the management of these patients.

METHODS

A retrospective review of fetuses with congenital lung lesions managed with maternal BMZ from 2003 to 2014 was performed.

RESULTS

Forty-three patients were managed with prenatal steroids (28 single course, 15 multiple courses). Single course recipients demonstrated a reduction in lesion size and resolution of hydrops in 82% and 88% of patients respectively compared to 47% and 56% in recipients of multiple steroid courses. Survival of multiple course patients (86%) was comparable to that of single course patients (93%) and improved compared to non-treated historical controls. Multiple course recipients demonstrated an increased need for open fetal surgery and postnatal surgery at a younger age.

CONCLUSION

Fetuses who fail to respond to a single course of BMZ may benefit, as indicated by hydrops resolution and improved survival, from additional courses. However, failure to respond is indicative of a lesion which may require fetal or immediate neonatal resection.