Journal of Pediatric Surgery VOL31,NO 10 OCTOBER 1996 Fetal Endoscopic Tracheal Occlusion (‘Fetendo-PLUG’) for Congenital Diaphragmatic Hernia By Erik D. Skarsgard, Martin Meuli, Karen J. VanderWall, John F. Bealer, N. Scott Adzick, and Michael R. Harrison San Francisco. California 0 Despite recent advances in surgical technique, posthy- sterotomy preterm labor remains a major determinant of postoperative fetal morbidity and mortality after in utero repair of congenital diaphragmatic hernia (CDH). Temporary fetal tracheal occlusion, or “PLUG” (Plug the Lung Until it Grows), reverses the pulmonary hypoplasia seen in experi- mental models of CDH and provides an alternative treatment strategy for some fetuses with CDH. Adaptation of current, minimally invasive surgical technology to the PLUG tech- nique allows treatment of CDH without opening the uterus. In this report the authors describe a video-fetoscopic, intra- uterine technique of tracheal occlusion (called Fetendo- PLUG) that could be used in human fetuses with CDH. The technique was developed in four fetal lambs that underwent video-fetoscopic intervention at 110 days’ gestation1 (full term, 145 days), having undergone open creation of diaphrag- matic hernias at 75 days. After maternal laparotomy and uterine exposure, the fetal head was located and a 5-mm curved, balloon-cuffed trocar was introduced through a uterine puncture directly into the fetal oral cavity. A steerable “bronchoscope” (with an instrument channel) was used to endoscopically intu- bate the trachea through the trocar, and the trocar was advanced over the bronchoscope and its balloon inflated to provide secure tracheal access below the vocal cords. Next, a IO-mm trocar was placed directly over the fetal neck, and the amniotic space was expanded with warm saline. A 5-mm laparoscope was intro- duced, and under simultaneous, dual video-fetoscopic (endotra- cheal and endoamniotic) visualization, a l-mm nephrostomy puncture wire was advanced along the instrument channel of the bronchoscope, through the anterior wall of the trachea and fetal neck, into the amniotic space, then through the uterine wall to the outside. Withdrawal of the bronchoscope over the wire left a 5-mm endotracheal “trocar channel” along which a compressed, gelatin-encapsulated, polymeric foam insert (outer diameter, 4.8 mm) could be delivered by suture attachment to the guide wire. Once the foam was in its final endotracheal position, dissolu- tion of the gelatin membrane allowed expansion of the foam to produce a water impervious tracheal occlusion This two-trocar video-fetoscopic PLUG technique was performed successfully in all four fetuses, with a sequential decrease in operating time (median, 3.5 hours). Although two fetuses aborted postoperatively, the other two were carried success- fully to term and demonstrated the anticipated physiological effects of adequate tracheal occlusion at the time of delivery. Copyright o 1996 by W. B. Saunders Company INDEX WORDS: Congenital diaphragmatic hernia, video- fetoscopy, tracheal occlusion, fetal surgery. T HE HIGH postnatal mortality rate from pulmo- nary hypoplasia associated with congenital dia- phragmatic hernia (CDH) diagnosed before 24 weeks’ gestation has led to the evolution of in utero tech- niques that promote prenatal pulmonary growth.’ Although in utero diaphragmatic hernia repair per- mits fetal pulmonary growth, the hysterotomy neces- sary for fetal exposure causes increased fetal morbid- ity and mortality through postoperative preterm labor.2 Because the risk of preterm labor appears to be closely related to the size of the hysterotomy, a “minimally invasive” treatment strategy should in- crease significantly the safety of prenatal surgical therapy for fetuses with CDH. Recently we reported our experience with in utero tracheal occlusion, or “PLUG” (Plug the Lung Until it Grows), in a 27-week human fetus with CDH.3 By adapting minimally invasive video-fetoscopy to our current technique of fetal tracheal occlusion, we have developed a means of treating experimental CDH without opening the uterus. This new experimental video-fetoscopic technique (which we call Fetendo- PLUG) is the focus of this report. MATERIALS AND METHODS Creation of Diaphragmatic Hernia Four time-dated gravid ewes (Torrel Farms, Ukiah, CA) under- went fetal surgery at 75 days’ gestation (full term, 145 days) for creation of fetal diaphragmatic hernias, as described previously.4 From the Fetal Treatment Center, University of California, San Francisco, CA. Supported in part by the Hospital For Sick Children Foundation, Toronto, Ontario, Canada. Address reprint requests to Michael R. Hamson, MD, Fetal Treat- ment Center, University of California, San Francisco, 1601 HSq 513 Pamassus Ave, San Francisco, CA 94143-0570. Copyright o 1996 by WB. Saunders Company 0022-3468196131IO-OOOl$O3.OOlO JournalofPediatricSorgery, 's'ol31,No 10 (October),1996: pp 1335.1338 1335