Cirugía fetal para malformaciones congénitas diagnosticadas en periodo perinatal

Fetal surgery is used for specific congenital abnormalities associated with a poor postnatal prognosis. Prenatal surgery typically involves opening the gravid uterus (with a Cesarean surgical incision), surgically correcting the abnormality, and returning the fetus to the uterus and restoring uterine closure. Minimally invasive procedures through single or multiple fetoscopic port incisions are also being developed. Due to a number of factors, including the rarity of the conditions and the small number of centers specializing in fetal interventions, the evidence on fetal surgery is limited. Fetal surgery for many congenital conditions, including congenital diaphragmatic hernia (CDH) and heart defects, has not been shown to improve health outcomes compared with postnatal treatment. The available evidence is insufficient to demonstrate that fetal tracheal occlusion for CDH and fetal intervention for evolving hypoplastic left heart syndrome (HLHS) and critical pulmonary stenosis or pulmonary atresia provides improved health outcomes. For these and other applications of fetal surgery that are currently considered investigational, additional studies are needed to identify appropriate candidates and to evaluate longer term outcomes compared with postnatal management. For conditions leading to fetal hydrops (certain cases of congenital cystic adenomatoid malformation, bronchopulmonary sequestration, or sacrococcygeal teratoma), for which mortality approaches 100%, fetal surgery may be considered medically necessary. For bilateral urinary tract obstruction, evidence from retrospective and prospective cohort studies summarized in the 2011 Agency for Healthcare Research and Quality technology assessment on fetal surgery suggests that vesicoamniotic shunting improves survival, at least in the short term. A recent small, randomized controlled trial evaluating the use of vesicoamniotic shunting found limited benefit from the procedure when data were analyzed by intention-to-treat analysis. However, the study’s significant limitations, including low enrollment leading to early cessation of the study and significant crossover between treatment and control groups, make it difficult to draw firm conclusions from its findings. As such, vesicoamniotic shunting for bilateral urinary tract obstruction may also be considered medically necessary to minimize the effects of this condition on kidney and lung development. Additional studies for these surgeries are needed to better define the appropriate surgical candidates, the most effective timing of the interventions, and the long-term health outcomes in surviving children. Data from the MOMS trial showed that prenatal repair of myelomeningocele reduces the need for shunting in the first 12 months after delivery and improves a composite measure of mental and motor function, with adjustment for lesion level, at 30 months of age. Prenatal surgery also improves the degree of hindbrain herniation and the likelihood of being able to walk independently when compared with postnatal surgery. The long-term impact on function needs to be evaluated, and benefits must be balanced against risks to mother and child. Thus, fetal surgery may be considered medically necessary following informed decision making for cases of prenatal myelomeningocele that meet the criteria of the MOMS trial.