You are here: MEDICA Portal. MEDICA Magazine. Topic of the Month. Volume archives. Our Topics in 2010. September 2010: Medicine in the womb. Blood.
“We treat the Twin-to-Twin Transfusion Syndrome most frequently“
Thanks to fetal surgery, some children
can be treated at an early stage in the
womb.; © Hemera
MEDICA.de talked to Professor Thomas Kohl, Chief of Staff at the German Center for Fetal Surgery and Minimally Invasive Therapy (DZFT) at the University Hospital in Gießen about the possibilities for fetal surgery and what the special challenges of his job are.
MEDICA.de: Professor Kohl, you perform surgery on the smallest of people, that is unborn babies. Starting at which pregnancy week can surgeries be performed nowadays?
Thomas Kohl: Surgery on unborn babies can already be done starting at the 13th or 14th week of gestation. A baby has completed the embryonic phase and is now called a fetus with a weight of about 50 grams. So it could be extremely small babies, which can be treated in case of an emergency.
MEDICA.de: Which interventions do you perform frequently?
Kohl: Most interventions we perform are based on the so-called twin-to-twin transfusion syndrome. Admittedly you don’t perform the surgery on the actual twins, but rather you seal the pathogenic blood vessels on the placenta of the mother. This is an intervention which is often already performed starting at the 16th/17th week of gestation, but sometimes also up to ten weeks later. In addition we treat children with severe types of diaphragmatic hernia. This disease causes the lungs to not be able to develop sufficiently, because almost all abdominal organs go up into the chest cavity near the lungs.
MEDICA.de: Can you always determine whether a consecutive complication results from the surgery itself or due to other factors?
Kohl: No, of course we cannot always determine that, though often we can identify it. If we treat the twin-to-twin transfusion syndrome for example, the disease typically involves a significant increase in the amount of amniotic fluid. This increase is the result of a circulatory disturbance in one twin i.e., expectant mothers may carry up to ten liters of amniotic fluid in their belly. This leads to an excessive distension of the amniotic sac, a reduction of the cervix to the point of triggering premature labor: a very serious risk factor. Unfortunately, through this we also lose some of the children. That is to say, even if we are technically successful in lasing: If before the intervention there already has been any premature labor, bleeding, signs of infection or even a premature rupture of the amniotic sac, you can predict with one hundred percent certainty that the child will be born too early. However, despite these unfavorable conditions a considerable amount of children can be saved.
Unborn babies with diaphragmatic hernia share a similar problem. If we get to choose the time of treatment, it is in the 34th to 35th week of gestation – we get great treatment results during that time. Yet also with this disease, many expectant mothers have an increased amount of amniotic fluid, because the children are not able to properly absorb the amniotic fluid. The reason for this is that during the course of the belly organs moving up into the chest cavity, the esophagus gets bent. But the amount of amniotic fluid is also regulated by the unborn baby absorbing it, and through this absorption by the stomach and gut the fluid in return gets back again into the maternal circulation. If this mechanism is interrupted, a highly increased amount of amniotic fluid can also lead to problems with this disease – problems, which are brought along to the treatment.
MEDICA.de: Do the mothers need to stay a long time at the hospital after the surgery?
Kohl: Only rarely anymore. Usually most expectant mothers can leave the hospital again after the surgery within three days. Even after closing a fetal spina bifida, nowadays the mother-to-be returns home after one week. Not until weeks later will she get admitted again to deliver the baby.
Most women learn about their unborn baby’s disease during a prenatal ultrasound screening:
N.B. (age 31): “During the detailed fetal ultrasound in week 21 of my pregnancy, it was detected that my baby had an open spine, called Spina bifida. I had surgery in week 25 of my pregnancy – of course you are very worried even after the surgery and wondering how life with a handicapped child will be. But the surgery has calmed me down quite a bit.“ (Bild: panthermedia.net/Severin Schweiger)