By Rosanne Moore
Advanced technology has made successful separation surgeries more common than they once were. The medical challenges and risks, however, remain significant. And in many cases, the decision to attempt the separation of conjoined twins can pose profound ethical questions as well. Texas Children’s addressed the Mata twins’ case both clinically and ethically through the hospital’s medical ethics review process.
While the chances of having conjoined twins are rare — one in every 200,000 live births — the overall survival rate for these babies is only 25 percent. About 40 to 60 percent of conjoined twins are stillborns, and another 35 percent die shortly after birth due to serious health anomalies. The separation of conjoined twins can be risky, depending on how the twins are connected. The greater the number of vital organs the babies share, the more difficult the odds for a positive outcome. Approximately 250 successful separations in which one or both twins have survived have been recorded worldwide, according to the American Pediatric Surgical Association. The number is small because the decision to attempt separation is not taken lightly.
Since Texas Children’s opened its doors in 1954, multiple sets of conjoined twins have been referred to the hospital for consideration. However, in many of these cases, separation was not medically possible. Surgeons at Texas Children’s Hospital have performed three successful separation surgeries. The first pioneering procedure occurred February 16, 1965, when a team of surgeons separated 9-week-old conjoined twins Kimberly and Karen Webber. The Webber twins were connected at the liver and pericardium — the membrane enclosing the heart. On June 9, 1992, Texas Children’s surgeons successfully separated Tiesha and Iesha Turner, who were 1 year old and shared a sternum, liver, entwined intestines and fused organs.
The Mata twins’ surgery was the third successful separation surgery performed at Texas Children’s. On February 17, 2015, 10-month old Knatalye Hope and Adeline Faith Mata were detached during a marathon 26-hour operation. The girls were born connected from the chest to the pelvis, sharing a chest wall, pericardial sac, diaphragm, liver, intestinal tract, urinary system and reproductive organs.
TO SEPARATE OR NOT TO SEPARATE
The rarity of separation surgeries in cases of conjoined twins not only reflects the medical complexity of the surgeries, but also the ethical questions raised by medical procedures that have terribly uncertain outcomes.
Lead surgeon Oluyinka Olutoye, MD, a pediatric surgeon and co-director of Texas Children’s Fetal Center, has participated in four conjoined twins’ separation surgeries, one at Texas Children’s Hospital and three at the Children’s Hospital of Philadelphia. He emphasized that the potential for success depends on many factors, the most important being where the twins are connected and which structures they share.
Olutoye, also professor of Surgery at Baylor College of Medicine, recalls a time in his medical training when he and his surgical colleagues were presented with a complex case involving conjoined twins who were supported by the heart of one twin.
“One baby had a thriving heart, while the other twin didn’t have a heart at all and was being fed by blood vessels from the healthier twin,” Olutoye said. “We knew that if we separated them, the one without a functioning heart would not survive. But, at the same time, if we did not separate them, the heart would not be able to support both babies as they grew older.”
The decision was wrenching. But the family and their medical team elected to proceed with the separation surgery.
As Texas Children’s Hospital’s medical ethicist, Laurence McCullough, MD, consults on patient cases in which treatment decisions are unclear or morally difficult. Every Thursday morning, he and a multidisciplinary team of physicians, surgeons, counselors and social workers huddle in a large conference room at the hospital to discuss the ethical implications of new and ongoing patient cases — one of which was the Mata twins’ case.
“My role in this process is to ensure all ethical dimensions of each case are clearly identified so our medical staff can provide guidance to the families,” said McCullough, a professor of Medicine and Medical Ethics at Baylor College of Medicine. “We have a thorough process for identifying ethical challenges and putting plans in place to manage them and determine whether surgery is ethically permissible in certain cases.”
When determining whether to proceed with surgery for conjoined twins, McCullough said some cases are not clear-cut. One ethical approach might call on the principle of double effect, in which the attempted separation could result in irreversible harm or death to one twin while improving the quality of life for the other twin. According to this principle, it is sometimes permissible to cause harm as a side effect (double effect) of bringing about a good result — as long as the two outcomes are causally independent. Another ethical perspective is that saving one life may be better than losing two.
In the case of the Mata twins, the double effect principle did not apply: Knatalye and Adeline had enough separate functioning body parts to enable them to sustain lives apart from each other. In this case, then, the medical challenges were paramount.
“We knew that one twin was going to be more challenging than the other based on the anatomy and what their structure was like,” Olutoye said. “While they didn’t share equal parts, we had to determine if they had enough parts to survive and function. It became more of an issue of how could we medically accomplish this so both babies survive.”
Throughout the entire process, from the initial diagnosis in utero to the day of separation, lead surgeon Darrell Cass, MD, and others involved in the care of the Mata twins held regular meetings with the family to keep them informed — ethically essential in medical decision-making.
“We made sure we set the right expectations for the Mata family from the start,” said Cass, a pediatric surgeon, co-director of Texas Children’s Fetal Center, and associate professor of Surgery, Pediatrics and Obstetrics and Gynecology at Baylor. “We explained all of the steps that must be taken before any surgical intervention could take place to ensure the best possible outcomes for both girls.”
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