Midwest Fetal Care Center, a collaboration between Children’s Minnesota and Allina Health, recently completed its journey to become a comprehensive treatment destination for developing babies and their mothers with the addition of an advanced prenatal intervention: open fetal surgery (OFS).
Three decades ago, Michael Harrison, MD, a pediatric surgeon at the University of California, San Francisco, proposed operating on babies in utero to treat certain conditions that were likely to prove lethal during pregnancy, such as bladder outlet obstruction. Since then, the pool of candidates for OFS has widened to include fetuses who are likely to benefit from prenatal surgery for non-lethal conditions, including, most commonly, myelomeningocele (MMC) — a neural tube defect that is a severe form of spina bifida.
Failure of closure of the spinal canal anywhere along the spine can lead to a neural tube defect. MMC is present in one out of every 3,000 live births and is the most common birth defect in babies. Spina bifida can cause a variety of symptoms that limit quality of life after birth, according to the National Institutes of Health. In 2011, the landmark Management of Myelomeningocele Study — a federally sponsored prospective randomized investigation to determine the efficacy of prenatal MMC repair compared with postnatal repair — showed OFS benefited infants in a variety of ways at the 30-month mark after surgery, including a 50 percent reduction in the rate of shunt placement to treat hydrocephalus (a common problem for children with spina bifida) and improvements in unassisted ambulation and neurocognitive function. A recent update to the study found these benefits persisted beyond 30 months.
MMC repair is the primary focus of the OFS program at the Midwest Fetal Care Center, a collaboration between Children’s Minnesota and Allina Health. The program debuted in early 2016 as one of a few such programs in North America. Offering OFS was the culmination of the pragmatic, methodical process of building the type of advanced fetal care center that could provide such a complex intervention.
Dr. Joseph Lillegard, MD, PhD
“After about a decade, we arrived at a point where we had great MRI and ultrasound capabilities, we were experienced at administering anesthesia to both mothers and babies, and we were comfortable caring for mothers and babies who had undergone OFS at other institutions,” says Joseph Lillegard, MD, PhD, pediatric and fetal surgeon at Children’s Minnesota and Research Director of the Midwest Fetal Care Center. “The next step was to offer OFS ourselves. We performed our first case, an MMC repair, in February 2016 and plan to do 10 to 20 cases per year. Of the approximately 40 babies we see each year with neural tube defects, we expect one-third to one-half will be eligible for surgery.”
A screening ultrasound around 20 weeks gestation will reveal a neural tube defect, at which time an obstetrician or maternal-fetal medicine specialist may refer an expectant mother to Minnesota Perinatal Physicians (MPP) and the Midwest Fetal Care Center.
“First, we completely assess the fetus and the mother to see if they may be candidates for prenatal repair,” says David Lynch-Salamon, MD, Medical Director of the Midwest Fetal Care Center. “We also assess families’ resiliency to cope with the stressors that accompany this diagnosis, and reassure them that we will fully support the plan of action they choose. Families are reassured that their pregnancy will be cared for by our Center, which coordinates care across the numerous specialties required to treat these patients.”
The Center’s clinicians weigh a variety of factors when determining eligibility for OFS, including:
- Ability of the family to comply with the postoperative care plan
- Comorbidities of the mother and infant
- Potential of the surgery to positively affect the infant’s disease process
- Presence of a support network
- Ultrasound-indicated characteristics that are favorable for prenatal repair
“When looking for favorable characteristics, we start with the brain,” Dr. Lillegard says. “If the ventricles are larger than 15 millimeters, we know we’re unlikely to impact the baby’s need for shunting to treat hydrocephalus , but we may delay the timing of a shunt, which has a significantly positive impact on neurocognitive function and complications related to shunts. Other factors we look at include the presence and severity of hindbrain herniation, the level of the spine at which lesions are present, and lower extremity function and movement. No two children with neural tube defects are alike or stand to benefit from OFS equally.”
(l-r) Brad Feltis, MD, PhD, David Lynch-Salamon, MD, Marijo Aguilera, MD, Joseph Lillegard, MD, PhD
“We benefited from collaboration with other centers around the country as we assembled the infrastructure and expertise necessary to offer open fetal surgery. We would like to pay it forward by being a strong partner in our region for families and physicians.”
— Brad Feltis, MD, PhD, PEDIATRIC AND FETAL SURGEON AT CHILDREN’S MINNESOTA AND Surgical Director of the Midwest Fetal Care Center
Brad Feltis, MD, PhD
Characterized by Collaboration
No trait is more central to the OFS program at the Midwest Fetal Care Center than multidisciplinary collaboration, which begins with each expectant mother’s initial consultation and extends through the surgery to lifelong follow-up with patients. The OFS team includes maternal-fetal medicine specialists, pediatric surgeons, pediatric cardiologists, pediatric neurosurgeons, neonatologists, radiologists and anesthesiologists, as well as care coordinators, nursing and technical support staff, and social workers to address the psychosocial aspects of prenatal surgery and postoperative care.
During an initial visit to the Midwest Fetal Care Center, each expectant mother has a level II ultrasound study to determine the severity and extent of MMC in the fetus. Afterward, she and her family meet with Dr. Lillegard and either Dr. Lynch-Salamon or Marijo Aguilera, MD, the maternal-fetal medicine specialists, to discuss the diagnosis and treatment options in detail.
“I always begin the conversation by saying we are there to provide them with information and comfort so they can choose the option that is best for their family,” Dr. Lillegard says. “We discuss prenatal and postnatal surgical repair as well as what options are available if intervention is not appropriate for them. Some families elect to terminate the pregnancy. We want them to know we will fully support any decision they make.”
“When the team is evaluating patients, my job is to explain to the parents what they can expect for their child after delivery, whether they choose prenatal or postnatal intervention,” says Ellen Bendel-Stenzel, MD, neonatologist with the Midwest Fetal Care Center. “I walk parents through the process after delivery and postnatal stay in the NICU. While the perinatologists and fetal surgeons change the course of the disease process, my partners and I work to optimize the factors that cannot be reversed by fetal intervention alone.”
Potential candidates for OFS undergo a fetal echocardiogram, a fetal MRI and amniocentesis. When the results are available, the full OFS team meets in a fetal board to make the final determination as to the patient’s candidacy for surgery.
“Everyone has a voice and a vote,” Dr. Lillegard says. “We try to arrive at unanimous decisions.”
If a patient is an appropriate candidate, the team schedules the surgery for a date between 23 and 26 weeks into gestation to minimize complications during the remainder of the pregnancy, including premature rupture of membranes and preterm labor.
Intervention and Next Steps
Patients are admitted to The Mother Baby Center at Abbott Northwestern and Children’s Minnesota the night before OFS. The next morning, a team of 15 to 20 clinicians performs the operation.
“Many different subspecialists come together to care for the mother and fetus during the operation,” says Kirsten Dummer, MD, pediatric cardiologist from The Children’s Heart Clinic who works with the team at Midwest Fetal Care Center. “My role is to monitor the fetal heart with ultrasound throughout the procedure. This starts when the mother receives anesthesia and continues through the end of the case with heart rate and function reports. Changes in placental blood flow, maternal anesthesia and physiologic responses to neurosurgery can affect fetal heart rate and function. The information I obtain via ultrasound can affect management, including changing the dose of maternal anesthesia, altering the amniotic fluid infusion rate, changing the position of the fetus and temporarily waiting to proceed until the fetus recovers adequate heart rate and function.”
After the mother receives general anesthesia, the surgeon makes an incision similar to that of a Caesarean section and exposes the abdominal wall and fascia. The surgeon then exposes the uterus, uses ultrasound to plan where to make a hysterotomy so the placenta is unaffected, makes the incision and uses a specially designed stapler to lengthen it and reveal the baby inside the uterus.
“We shift the baby inside the uterus so the neurosurgeon and I can see and repair the neural tube defect,” Dr. Lillegard says. “Once we’ve covered and repaired the defect, we close the uterus, reposition it in the abdomen, and close the abdomen.”
The mother typically stays in the hospital for four or five days before returning home. The team follows her closely with weekly ultrasound studies until delivery — ideally occurring at 36 weeks — at which time she has a C-section. All infants who undergo OFS spend time in the neonatal intensive care unit at Children’s Minnesota after birth. Those who reach 36 weeks gestation prior to delivery typically go home after a week, while others may need to stay longer until issues of prematurity resolve.
After birth, babies enter the Children’s Minnesota spina bifida program until they turn 18, at which time they transition to adult care. Many of the same clinicians who are involved in OFS remain part of the patients’ care team afterward. As the clinicians who often know patients best, primary care physicians are uniquely positioned to oversee and ensure compliance with care plans throughout childhood, and the team at the Midwest Fetal Care Center works closely with their colleagues in the community in this regard.
“Children with spina bifida are as complex as patients get,” says Brad Feltis, MD, PhD, pediatric and fetal surgeon at Children’s Minnesota and Surgical Director of the Midwest Fetal Care Center. “Treating them is not just about doing one complex, in utero surgery. It’s about forming a lifelong relationship with families and helping children reach their complete potential using treatments ranging from advanced neurosurgical intervention to psychosocial counseling, and everything in between.”
Just Getting Started
The future for OFS, as a field and at the Midwest Fetal Care Center, is bright. Drs. Lillegard and Feltis envision the indications for OFS expanding to include more conditions, as well as shifting to fetoscopic techniques to reduce maternal risks. In the meantime, the team at the Midwest Fetal Care Center continues building experience with OFS and changing lives in the process.
“We began offering OFS for a simple reason: to meet an unmet need,” Dr. Feltis says. “Before, if we saw a pregnant patient whose baby needed OFS, we’d recommend she be referred to an experienced, advanced fetal care center elsewhere in the U.S., of which there are only a few. Families who couldn’t travel out of state for care faced substantial stress. Now, we can offer the full breadth of available fetal therapies to anyone who walks through our doors.”
“Midwest Fetal Care Center could not exist without the passionate contribution of everyone involved in the care of these families as well as the ongoing collaboration between Children’s Minnesota and Allina Health,” Dr. Lynch-Salamon adds. “I am thankful for them all.”
For information about the Midwest Fetal Care Center, a collaboration between Children’s Minnesota and Allina Health, visit midwestfetalcarecenter.org.