The EXIT Procedure: Multidisciplinary Specialty Surgery for Complex Airway Anomaly in Neonatal Patients

March 27, 2019 Ex utero intrapartum treatment (EXIT) is a highly specialized, multidisciplinary surgical procedure used to deliver babies who have been diagnosed prenatally with various airway anomalies leading to airway compression or blockage, making a normal vaginal birth or traditional Caesarean section delivery unviable for the baby. Anomalies or conditions leading to airway compression for which the EXIT procedure may be needed include cervical teratomas, cystic hygromas, or a blockage of the airway from congenital high airway obstruction syndrome (CHAOS).

Diagnosing and treating some of rarest, most complex prenatal conditions amenable to in utero surgical intervention is a collaboration between the UPMC Newborn Medicine Program, the Fetal Diagnosis and Treatment Center, the Center for Innovative Fetal Intervention (CIFI), and the Center for Advanced Fetal Diagnostics (CAFD).

“Achieving good outcomes for these highly complex cases is not something every hospital or even academic medical center can accomplish. It takes a tremendous amount of resources, planning, procedural skill, and the technical expertise of dozens of individuals before, during, and after the surgery to perform this procedure safely and effectively,” says Kalyani Vats, MD, assistant professor of pediatrics, a neonatologist with the UPMC Newborn Medicine Program, co-Director of the CAFD at UPMC Magee-Womens Hospital, and director of triage and antenatal consult services, also at UPMC Magee.The ability to conduct EXIT procedures, and to conduct them safely and successfully, can be accomplished only by a multidisciplinary team of highly skilled, physicians, surgeons, and nurses operating in an environment with the necessary infrastructure and expertise to transform a potentially fatal neonatal emergency into a controlled situation.UPMC is one such place with the ability to successfully navigate the complexities of the EXIT procedure, and it has been doing so for close to 15 years. The EXIT team at UPMC comprises experienced, highly skilled clinicians from multiple specialties and hospitals, including maternal-fetal medicine, maternal-fetal anesthesia, neonatology, pediatric surgery, otolaryngology, obstetrics, and nursing, along with an operating room that is specifically designed for performing fetal procedures. Clinicians at UPMC performed their first EXIT procedure in 2004, and have since conducted several EXIT and PRESTO (Presence of Extra Surgical Team at Operation) procedures (PRESTO is similar to EXIT, yet is a less extensive procedure). EXIT is a rare procedure; however, when it is called for it may be the only way to save the life of the baby.

The Center for Advanced Fetal Diagnostics

The CAFD is a multidisciplinary service primarily housed at UPMC Magee. This service provides comprehensive care to patients and their providers following the prenatal diagnosis of fetal anomalies.

Primary components of this service include prenatal ultrasound; genetics (including both genetic counseling and reproductive geneticist services); maternal-fetal medicine; neonatology; pediatric surgery. Additionally, the CAFD works closely and coordinates care with various pediatric subspecialties, that include cardiology, urology, neurology, neurosurgery, radiology, and others. The CAFD also works closely with the CIFI to provide comprehensive fetal surgery.

In a true multidisciplinary fashion, weekly meetings review CAFD patients and provide an opportunity for input from multiple specialties into the care of each patient. This coordination of care promotes seamless continuity from prenatal diagnosis and counseling through delivery and postnatal care.

EXIT Procedure Indications, Variations, and Best Practice Guidelines at UPMC

The most common indication for the EXIT procedure is a fetus with an airway compromised by a neck mass such as a cervical teratoma or lymphangioma, tracheal or laryngeal atresia (resulting in CHAOS), or severe micrognathia. The EXIT procedure allows time to secure the fetal airway by laryngoscopy, bronchoscopy, endotracheal intubation, or tracheostomy, depending upon the nature of the condition and the surgical preplanning and can have several
variations (See Table 1).

EXIT-to-Airway turns an airway emergency into a controlled, planned procedure. The EXIT-to-ECMO strategy is useful in cases of severe pulmonary or cardiac malformations in which separation from uteroplacental circulation will lead to immediate instability in the newborn. In such cases, EXIT-to-ECMO strategy can be applied to secure the airway and insert venous and arterial cannulas for ECMO while on placental support. This approach avoids a possible period of hypoxia or acidosis during neonatal resuscitation.

Not all babies with airway obstructions will be candidates for the EXIT procedure. Some conditions may be able to be handled through alternative procedures or airway management protocols.

“Not every compromised airway calls for an EXIT procedure, nor does every mass in the neck. We look at all the signs and clues for the well-being of the fetus to determine airway function in advance. If it appears to be a life-threatening condition, then EXIT may be an option, but many other factors contribute to the final determination,” says Dr. Vats.

Table 1. Variations of the EXIT Procedure and Their Indications
Procedure: EXIT-to-Airway
Indications:
• Cervical teratoma/lymphangioma
• Congenital high airway obstruction syndrome (CHAOS)
• Micrognathia (small chin)
Procedure: EXIT-to-Extra-Corporeal Membrane Oxygenation (ECMO)
Indications:
• Congenital diaphragmatic hernia (CDH)
Procedure: EXIT-to-Resection
Indications:
• Congenital pulmonary airway malformation of the lung (CPAM)
• Bronchopulmonary sequestrations (BPS)
• Mediastinal, cervical, or oral teratoma

Planning and Preparations for an EXIT Procedure

Virtually all cases of significant high airway obstruction are diagnosed prenatally via ultrasonography and confirmed by fetal magnetic resonance imaging (MRI) during the mother’s pregnancy. Fetal MRI is an important aspect of the consultation and planning process for when an EXIT procedure may be a viable surgical option for both mother and baby.

Sufficient time is needed to assess both the mother and fetus, determine the extent of the airway anomaly, and uncover other issues that may be compromising the health or viability of the fetus. A plan for the nature of the EXIT procedure is needed. Also, alternate plans for care, should an EXIT procedure not be warranted, desired, or are considered safe. This process takes significant time and coordination between many clinical specialties, and then the family must be informed and counselled on all the options, risks, and unknowns that factor into such highly complex medical and surgical decisions.

“There are cases where we could perform an EXIT procedure, but other underlying issues may render securing the airway and ultimately repairing it moot. However, if the airway anomaly is the only major issue affecting the fetus, we can secure the airway through the EXIT procedure, and our ENT surgeons can continue to follow, evaluate, and reconstruct the airway later,” says Dr. Vats.

Planning for an EXIT procedure typically begins early, usually at 24 to 25-weeks gestation. Planning includes diagnostics through the CAFD, consultations and case reviews with maternal-fetal medicine, ENT, neonatology, surgery, anesthesia, and any other specialties that may be needed based on the baby’s underlying conditions.

Premature babies — especially those under 32-weeks gestation — are not good candidates for an EXIT procedure. The complications and contributing factors in a fetus at that gestation generally outweigh benefits of the EXIT procedure, according to Dr. Vats.

“If the mother is fine, and the baby is fine, and no complications arise, we will expect to allow the pregnancy to continue for as long as possible so the fetus can grow and develop as much as possible, or until there is a change in status that warrants immediate intervention. The older and more mature the fetus is, when EXIT is performed, typically the better the outcomes will be. However, if we have an EXIT case that we are monitoring, the entire team must be on call and ready to go at a moment’s notice should the mother arrive in premature labor. This aspect factors heavily into our planning process,” says Dr. Vats.

A few days before the procedure is anticipated to occur, the entire team performs a walk through of the procedure in a special operating room used for EXIT. Every element of the procedure is choreographed in advance, including where everyone will be positioned, and where equipment will be placed. Every specialty taking part in the procedure has a dedicated area for their needs in the operating suite.

“Because these procedures are so rare, they present an excellent teaching and observational opportunity for all levels of medical trainee and care providers. We direct a live feed of the procedure to another room set up specifically to view our EXIT cases, where residents, fellows, students, and others can observe, in real-time, the progression and details of the procedure,” says Dr. Vats.

Surgical Details of EXIT at UPMC Magee and UPMC Children’s

At a fundamental level, the EXIT procedure serves a simple function. By keeping the baby attached through the umbilical cord to the placenta to sustain perfusion and respiration, the EXIT procedure allows the team the time they need to deliver the baby via C-section, work to establish or secure an airway through whatever means are called for, and then separate baby from mother.

It is a simple concept, but one that requires some of the most thorough and complex planning to execute that is likely to be seen in a surgical procedure.

“Our colleagues in anesthesia and maternal-fetal medicine play a critical role in the success of this procedure. The mother must receive general anesthesia for the C-section. The deep anesthesia she receives is done to achieve and maintain a state of uterine relaxation to preserve uteroplacental circulation, and a special uterine stapling device is used to open the uterus to prevent bleeding,” says Dr. Vats.

The team also must ensure that normal maternal blood pressure is maintained and that appropriate levels of fetal anesthesia are achieved without triggering cardiac depression. It is a delicate balance that must be struck, and the teams at UPMC have perfected their anesthesia protocols for the procedure.

Once the C-section is performed, the baby is then partially (the head and upper torso) delivered through the incision while remaining attached to the placenta through the umbilical cord. Anesthesia keeps the uterus soft and relaxed, which allows the placenta to continue to perform its function. The procedure preserves uteroplacental gas exchange so that the baby can continue to receive oxygen and nutrients from the mother while the team works to establish an airway that will permit the infant to breathe and obtain oxygen once he or she is fully delivered.
The baby is only partially delivered through the incision to naturally keep the baby warm without the need for other interventions to prevent hypothermia.

Potential risks to the EXIT procedure include intrauterine bleeding for the mother. For the baby, if endotracheal intubation fails, the surgical team will need to perform a tracheostomy to establish an airway before the procedure is completed and the baby whisked away to the NICU
for follow-up care.

Once the baby’s airway is established, and the delivery concludes, Dr. Vats and her neonatology team takes over and transfers the infant to the NICU where other procedures and care will take place. Further into the care plan, once the infant is stabilized in the UPMC Magee NICU, he or she is then transferred to the UPMC Children’s NICU for the balance of their care and follow-up procedures based on their needs.

Postprocedural Care

After the delivery, the baby receives specialized care in the neonatal intensive care units of the UPMC Newborn Medicine Program, either at UPMC Magee or UPMC Children’s. Babies who need help with respiration but do not require ECMO may be placed on a ventilator for respiratory support.

If called for as part of the surgical preplanning process, a pediatric surgeon also may perform additional procedure(s) to correct an underlying congenital anomaly that may be amenable to surgery.

Likewise, the mother will be monitored closely for hemorrhage, infection, or other postdelivery complications for an appropriate time period based on the specific nature of the case.

A debriefing session occurs upon conclusion of the procedure and before the team members depart. Team leaders from the various specialties involved in the case meet to briefly review the entire procedure and report their perspectives and opinions of how the entire case proceeded and any anticipated or unanticipated issues that arose. This initial debriefing is typically followed a few days later by another more detailed session where all team members, including nursing, participate to discuss the case. The entire EXIT team receives an update on how the mother and baby are progressing in their postoperative care, and the team also reviews the procedure notes and findings to identify, address, and collaboratively solve any issues that arose. The entire debriefing process is intended to inform and guide future cases, learning from any unique aspects that the cases provide and contributes to the evolution of best practices for these rare and complex deliveries.

EXIT Procedure — Key Team Members at UPMC

Stephen P. Emery, MD — Associate Professor and Director, Center for Innovative Fetal Intervention (CIFI) — UPMC Magee
Kalyani Vats, MD — Co-Director Center for Advanced Fetal Diagnostics (CAFD) — UPMC Magee
Jeffrey P. Simons, MD, FAAP — Professor, Pediatric Otolaryngology — UPMC Children’s
Allison Tobey, MD — Assistant Professor, Pediatric Otolaryngology — UPMC Children’s
Jonathan H. Waters, MD — Chief, Department of Anesthesiology — UPMC Magee
Linda S. Dudas, RNC, MSN, CNL — Unit Director, Labor, Delivery, and Antepartum — UPMC Magee
Barb Eichhorn, RN, BSN — Nurse Coordinator, CAFD and CIFI — UPMC Magee
Douglas A. Potoka, MD, FACS, FAAP — Assistant Professor of Surgery, Division of Pediatric General and Thoracic Surgery — UPMC Children’s