How is Anesthesia Used During Fetal Surgery?
Fetal surgery (surgery performed on a pregnant mother to treat her baby before it is born) can occur either during the middle of pregnancy or at the end of the pregnancy.
In all cases, anesthesiologists are involved to provide for the comfort and safety of pregnant mothers and their babies.
Fetal Surgery at ‘Midgestation’
Fetal surgery is scheduled in the middle of pregnancy, or "midgestation," for these conditions:
- Uneven blood flow to twin babies (twin-twin transfusion syndrome / TTTS)
- One healthy twin and one very sick twin (for example, twin reverse arterial perfusion syndrome / TRAP sequence)
- Abdominal organs like bowel and liver are in the baby's chest (severe congenital diaphragmatic hernia / CDH)
- Spina bifida / myelomeningocele
- Heart failure from a tumor with extra blood vessels (sacrococcygeal teratoma / SCT)
Minimally Invasive Fetal Surgery
Many fetal surgeries performed during the middle of pregnancy can be done with a "minimally invasive" technique. Small cameras are placed through a few small incisions in the mother's abdomen, where the fetal surgeon can reach and operate on the baby, the umbilical cord or the placenta.
Since the small cameras used during fetal surgery are called "scopes," the procedure is often referred to as "fetoscopy". During fetoscopy, the mother is usually kept comfortable with local anesthetics (similar to Novocain) or with epidural medicines (that make her numb from the waist down).
Additional medicine can be given to the mother through an IV (intravenous) catheter to help her relax and to facilitate the surgery.
Open Fetal Surgery
Some of the fetal surgery performed during the middle of pregnancy cannot be done using scopes; therefore, these fetal surgeries require an incision through the mother's abdomen and uterus so the baby can be reached for the operation.
Because an incision in the uterus is required, the mother is given anesthetic gases to prevent contractions. Therefore, both mother and baby are given general anesthesia for these "open" fetal surgeries.
When the mother is under general anesthesia, she is unconscious, and cannot feel pain or other sensations. She has a breathing tube (ETT) placed and her breathing is controlled by a ventilator.
Fetal Surgery at the End of Pregnancy
Ex-utero intrapartum therapy (EXIT) is a specialized fetal surgery performed at the end of pregnancy to enable safe delivery of the baby. Cases where this type of fetal surgery may be performed include:
- Large head or neck tumors in the baby which require a specialized breathing tube before delivery
- Severe heart or lung problems requiring immediate support with a specialized heart-lung machine (extra corporeal membrane oxygenation / ECMO)
EXIT surgery for delivery of the baby also requires an incision through the mother's abdomen, so both mother and baby are given general anesthesia for these fetal surgeries as well. General anesthesia prevents pain and all other sensations during the surgery.
What to Expect as a Patient
Before Fetal Surgery
Before surgery, you will meet your anesthesiologist. You will be asked questions about your medical history, allergies, current medications, previous anesthetic experiences and current health status. The anesthesiologist will examine your airway, heart, lungs and back. He or she will ask questions about your baby's gestational age, any tests and procedures done during pregnancy, and any known abnormalities that the baby may have.
After your anesthesiologist reviews your entire medical history as well as laboratory tests, he or she will discuss with you the risks and benefits of the type of anesthesia that is recommended for your surgery. Usually, the minimally invasive surgery (with the small incisions) has epidural anesthesia, and the fetal surgeries that require a larger incision for the mother (either in the middle of pregnancy or at the end) have general anesthesia.
The Day of Your Fetal Surgery
On the day of surgery, you will come to the Cincinnati Fetal Care Center at Cincinnati Children's for check-in. Before going to the operating room, you will change into a hospital gown and have an intravenous (IV) catheter placed. You will then be taken to the preop holding area where you will meet your anesthesia team. You may receive some medicine through the IV to help you relax just before leaving for the operating room.
After arriving in the operating room, you will sit up on the bed to have your epidural placed (if one is going to be used for your surgery). Once the epidural is in place, you will lie down and routine equipment will check on your heart's electrical activity, your blood pressure, and the oxygen levels in your blood.
If you are having fetoscopy, you may receive additional medicine to help you relax, and you may even take a nap during the surgery.
If you are having open fetal surgery (either in the middle of pregnancy or at delivery), you will then be given medicine to induce general anesthesia.
Once you are asleep, a breathing tube will be placed in your windpipe, a catheter will be placed in your bladder to measure your urine, and a special blood pressure monitor (an arterial line) may be placed in an artery (usually in the wrist). This equipment allows us to monitor your oxygen and carbon dioxide levels, fluid or hydration status, and blood pressure, at all times in order to keep you and your baby as safe as possible during surgery.
After Fetal Surgery
After surgery, you will awaken in the operating room. If a breathing tube was used, it will be removed before you are fully awake. The arterial catheter and epidural catheter may be removed in the operating room as well.
As you wake up more fully, you will be moved to a recovery area where specialized nurses will be with you until you are completely awake. Your family will be able to visit with you when you wake up, and your surgeon will talk with you about how the procedure went.
If you had an EXIT procedure, your new baby will most likely be transported directly to the Newborn Intensive Care Unit (NICU). A breathing tube will be used for a period of time after delivery to assist your baby's breathing, and medicines will be given through an intravenous catheter as needed. This care will be coordinated by neonatologists, who are pediatricians specialized in the care of newborns in an intensive care unit.
