Three-month-old conjoined twins Keylee Ann and Zoey Marie Miller were separated in a complex operation on April 7 at the Monroe Carell Jr. Children's Hospital at Vanderbilt.
The surgery was the first of its kind at Vanderbilt and is believed to be the first successful separation of conjoined twins in Tennessee. It was carefully planned and carried out by a team of 30 medical, surgical and nursing personnel. "It was pretty exciting to finally get them separated," said Wallace (Skip) Neblett, M.D., lead surgeon. "We talked about this and planned it for months as the babies matured."
The girls were born Jan. 4 in Johnson City, Tenn., and were immediately transferred via LifeFlight to the Neonatal Intensive Care Unit (NICU) at Vanderbilt's Children's Hospital. Together, they weighed 4 pounds, 12 ounces. The twins were cared for in the NICU for the last three months until they grew strong enough for the separation surgery. The babies' parents, Victoria Ford and Brian Miller, knew early in the pregnancy that the twins were conjoined. They had hoped to carry them to term, but when Zoey and Keylee were in fetal distress, the girls were born by Caesarean section 10 weeks early.
Conjoined twins are identical twins who develop from the same fertilized egg. In the United States the incidence for conjoined twins is one per 200,000 live births. The girls were "omphalopagus" twins, fused from the lower breastbone to the navel. They shared a liver and part of a diaphragm, and were born with one umbilical cord.
On March 24, Zoey required surgery for a heart defect to provide her with better oxygenation so she would be stronger for the separation surgery. David Bichell, M.D., chief of Pediatric Heart Surgery, performed that operation, which required that Keylee go under general anesthesia as well. The heart surgery was a success, but somewhat complicated the care of the twins. Staff and faculty in the NICU devised systems to administer Zoey the medications she would need to recover from her heart surgery, without causing harm to Keylee. The twins shared a common circulatory system and would be exposed to the same medications.
By the day of the separation surgery, the twins weighed a combined 7 pounds, 10 ounces and were in good health.
James O'Neill, M.D., professor of Surgery Emeritus, took part in the separation of Keylee and Zoey, and has participated in the surgical separations of 23 sets of conjoined twins, more than any other physician in the country. He planned and led three drills in the weeks leading up to surgery. "We wanted this to go smoothly, so we practiced to make sure we had all the essentials ready for potential complications. We were absolutely prepared," said O'Neill.
Since there were two patients, two full surgical teams had to be present in the operating room. Zoey's team was headed by Neblett, along with surgical fellow Barry Berch, M.D., and Keylee's team was lead by Walter Morgan, M.D., and junior fellow Josh Glenn, M.D.
The preparation alone, which involved starting IVs and keeping equipment cords and drapes out of the path of the constantly moving team members, took four hours. The first incision was made at 11:25 a.m. The babies were separated for closure procedures just 90 minutes later, at 12:52 p.m.
It turned out that both girls had all of the essential blood vessels and connectors so that each has her own completely functional liver without the need for complex repair. The abdominal muscles and skin flaps closed nicely in a mid-line scar, and the single navel they once shared was split in two so Zoey and Keylee would each have one.
Their recovery has been uncomplicated. If all goes well the family can take them home before summer, although Zoey must return for another heart surgery.