Only about 200 conjoined twins have been successfully separated in medical history, and Gary Hartman, MD, FACS, a pediatric surgeon at Lucile Packard Children’s Hospital, Stanford, CA, has successfully parted six of them in the last few decades. Most recently, on November 1, 2011, Dr. Hartman separated two-year-old twin girls, Angelica and Angelina Sabuco, in a nearly 10-hour procedure.*
The girls, born in the Philippines but living in San Jose, CA, with their parents and 10-year-old brother, were joined at the chest and abdomen, a condition called thoraco-omphalopagus. Because of how they were connected, the operation entailed separating their livers, diaphragms, breastbones, and chest and abdominal wall muscles.
The Sabucos began researching surgeons via the Internet while the girls were still in the Philippines. In their online research, the family came across Dr. Hartman’s work, and saw what they felt was a close parallel between their daughters and his most recent separation in 2007 of Yurelia and Fiorella Rocha-Arias from Costa Rica. They reached out to Dr. Hartman and began the dialogue.
“In this case, the parents absolutely wanted the twins separated. We could see changes in their muscular-skeletal systems already at the age of two; there was some ketosis in the spine as well as some deformity in the anterior chest wall,” said Dr. Hartman, professor of surgery at Stanford University School of Medicine, and director of regional pediatric surgery services. Although separating the girls posed significant risks, keeping the girls connected would have put their health in greater jeopardy, especially in terms of muscular and skeletal deformities that would worsen over time.
New technology lowers risks
Separation procedures typically are considered impossible when twins share a major organ, such as the heart or liver. And, indeed, that’s what Dr. Hartman perceived as the primary peril of operating on Angelica and Angelina. Performing surgery on conjoined twins is especially risky because if one twin dies during surgery, the other will die within hours.†
“The technical area we were most concerned about was separating the liver because there were two fairly large vessels that went directly across the plate that we needed to divide. That procedure went very well and was essentially bloodless, which didn’t surprise us because that had been the case with the last two sets [of conjoined twins] we did in 2007,” Dr. Hartman said. “We used a lot of the same equipment that our liver surgeons and transplant surgeons used for the last twins’ liver surgery, so there are some pretty good tools available now that make that procedure pretty bloodless.”
The technology has changed dramatically since the first time Dr. Hartman operated on conjoined twins in 1980 during his fellowship at the University of Oklahoma in Oklahoma City. The new technology primarily affected how the liver procedure was performed. Dr. Hartman’s team used a hydro-jet dissection instrument on the last two sets of twins to help them cleanly separate the liver. They also used an argon laser, as well as one of their regular laparoscopic endostaplers, on this set of twins, according to Dr. Hartman, who specializes in pediatric thoracic, cancer, and minimally invasive procedures.
“The case went quite well, pretty much as planned with no big surprises. We had really great imaging—a 3D CT [computed tomography]—so we had no surprises from a technical or anatomical standpoint,” he added.
Along with the liver, another area of concern was separating the girls’ sternum, mostly because an infection could occur if too little skin was available to cover the wounds. As a preventative measure before the operation, surgeons used tissue expanders to stretch the skin in the chest area to ensure they would have adequate skin to cover both girls.
When the surgeons disconnected the girls’ sternum it left a big gap at the breastbone, which needed to be reconstructed. For this procedure, the team was able to use some of the same materials that the plastic surgeons use in their craniofacial work. Peter Lorenz, MD, and his plastic surgery crew rebuilt the girls’ chests and abdominal walls by implanting a thick, custom-made resorbable plate in each girl’s chest where the sternum should be located. Then they grafted bone pieces that were removed during the separation onto the plates. The plates will take about a year and a half to dissolve, after which the grafted bone will have time to fuse, providing Angelica and Angelina with normal bones and stable chests. Reconstructing the girls’ chest walls also had the potential to create respiratory problems. But fortunately, none of these concerns were realized.
Whereas new technology contributes to a positive outcome from conjoined surgery, much of it, according to Dr. Hartman, depends on the anatomy and physiology of the patients, including whether they are physically separable and have an adequate complement of organs and limbs.
Planning and preparation
Perhaps surprisingly, Dr. Hartman said performing this operation wasn’t so different from performing other procedures, but the preparation and planning were especially challenging. He elaborated, saying, “The surgery itself at each of its steps is a fairly standard surgical procedure; it’s the fact that you have two patients and all the personnel and equipment to deal with that makes it complicated.”
When it comes to performing surgery on conjoined twins, Dr. Hartman says it requires a different mindset. “Working as a team is a long process, but I’ve gotten a good idea of how to get the team organized, and I feel good about that process now,” he said.
Preparing the team for this type of surgery takes at least a few months, but Dr. Hartman feels comfortable that he has learned how to get ready effectively, especially over the course of the last three sets of conjoined twins.
The team Dr. Hartman put together for the operation on Angelica and Angelina consisted of many of the same individuals who helped him successfully separate the conjoined twins from Costa Rica in 2007, which was the first time such a procedure had occurred at the Lucile Packard Children’s Hospital, and the last time Dr. Hartman performed surgery on conjoined twins. “We had multiple people at each step of the way, so we had a contingency plan if anything happened to any of the individuals on the team. A back-up person was always identified and available, so we had a lot of skill and depth on the team,” said Dr. Hartman.
“What we’ve been doing in the last three sets is to assemble a team from all the clinical specialties: anesthesia, pediatric surgery, plastic surgery, operating room (OR) staff, biomedical engineering, nursing staff, and clinical care units, so we have representatives from each area. Additionally, especially when we work with kids, we have the child-life specialists, and physical and occupational therapists,” explained Dr. Hartman. The operation last November required an extensive team of specialists, including 10 physicians, two anesthesia teams (each composed of six members), eight surgeons, and multiple scrub technicians and circulating nurses.
During the planning process, one representative from each of these disciplines participated in regular meetings, usually early in the morning every other week for a few months; as the operating date drew closer, they met every week.
“Even though we only had one person [from each specialty] at each of the planning meetings, that person would go back to their area and discuss the relevant issues, so the nurses and scrub techs from the ORs would talk with the rest of the members of the team and do their planning. So, the team itself was actually much bigger than the planning team,” Dr. Hartman explained.
“The expertise is what the subspecialists bring from their own specialties. The things we do during the case are not necessarily unique to conjoined twins surgery, although there are unique differences. But most of the techniques and procedures that the specialists bring are tools they use in other types of cases, so it’s not potently new each time,” said Dr. Hartman.
In addition to the complex nature of separating conjoined twins, this operation frequently raises ethical concerns. For example, the twins from Costa Rica suffered from congenital heart disease. Dr. Hartman said that at the time of that surgery the intensive care unit (ICU) space was limited, and the severity of the heart disease could have led to a difficult surgical procedure. The physicians involved in the case worried what would happen if each twin needed intensive care and there was only one spot available in ICU.
“The concern in the 2007 case revolved around the allocation of valuable resources, not the value of doing the procedure or the feasibility of doing it. We had no ethical concerns with this current set. We thought we could separate them and they would have a normal complement of organs and a normal outcome,” Dr. Hartman said.
In the several cases in which Dr. Hartman has been involved, ethical concerns were not raised because the risks associated with not operating far outweighed the risks of keeping the twins conjoined.
“The sets I’ve seen have had significant muscular-skeletal changes even in the first few months of life, which would only get worse as they aged,” said Dr. Hartman.
Dr. Hartman’s last three operations on conjoined twins were all heavily publicized beforehand, adding to the pressures associated with tackling a complex case. Dr. Hartman’s technique for coping with the stress is the same no matter what kind of surgery he’s performing.
“I’m not on call the night before or the night of surgery. Our family tries to do the regular routine the night before; we don’t do anything special. Personally, I try to have a good night’s sleep and not vary my routine too much. I don’t consciously handle the stress any differently with the extra publicity, but try to keep my routine as normal as possible.”
On the day of the surgery, access was limited to the OR. Security at the entrance ensured anyone entering the OR was wearing a badge identifying individuals with clinical responsibilities in the case. However, because there was an educational component to the procedure, Dr. Hartman said, “We are a teaching institution, so we did have fellows [involved] in the case, but there were a lot more people interested, so we had a video feed to a couple of rooms that were secured from the media. The video feed enabled people from the hospital and medical school to wander in and out of those rooms as their schedule allowed to see relevant parts of the case.”
Angelina and Angelica have now been out of surgery for several months. Their wounds are all healed, and the girls are home and eating normally. Within two months of the operation, they relearned how to walk.
“Beforehand, they were walking sideways and they were balancing each other. After the surgery, they had no counterbalance in front of them and they had to learn how to walk forward. Now, they are running up and down the halls when they come to clinic. They quickly learned how to walk on their own. The advantage of being young is that they are very flexible and malleable and adapt quite well,” explained Dr. Hartman.
The girls still have abnormal configurations of the chest, but Dr. Hartman is hoping that will improve with time. The chests are protruding out more than normal because they were growing out toward one another when the girls were attached.
“That’s the main thing we are monitoring at this point because their physical abilities seem to be developing quite rapidly. We are thinking that we might need to do some external bracing, and if that doesn’t work, then there’s some potential for further surgery, but hopefully not,” added Dr. Hartman.
To help the girls cope psychologically with the separation, Dr. Hartman has involved Packard’s child-life specialists and psychiatrists.
“In the last two sets of conjoined twin surgery, there were some significant but temporary changes. In both cases, before separation, one of the twins was more dominant than the other. And postoperatively the dominant twin has been unhappy. In fact, one of them wouldn’t even look at me for the first few days because we think she lost her little punching bag. The more submissive twin of the last two sets has been quite happy postoperatively. And, now the mother reports they are back to their more usual personalities,” said Dr. Hartman.
It appears that Angelica and Angelina are not the last set of conjoined twins that Dr. Hartman will get to watch develop as individuals. “Just recently, I was contacted by parents in Laos who gave birth to a set of conjoined twins. Their case looks very similar to the case we just did,” said Dr. Hartman.
With at least one other conjoined twin surgery looming in the near future, it appears that Dr. Hartman will have many more opportunities to achieve his goal of helping children lead better lives. “After months of intense planning and collaboration with almost every department in the hospital, it is rewarding to return two individuals home to happy, healthy lives. We’re tired, and very gratified.”
*Daily Mail (U.K.) Conjoined twins separated after nine hours of surgery in California hospital. Available at: http://www.dailymail.co.uk/news/article-2055828/Conjoined-twins-separated-hours-surgery-California-hospital.html. Accessed April 17, 2012.
†Donald B. Surgeons separate California conjoined twins. Associated Press. Available at: http://www.msnbc.msn.com/id/45126668/ns/health-childrens_health/t/surgeons-separate-california-conjoined-twins/. Accessed April 17, 2012.