Patient Education and Consent

After evaluation at a fetal treatment center, families should undergo extensive multidisciplinary counseling. Specialists should include fetal/pediatric surgeons, obstetricians, perinatologists, and anesthesiologists, as well as a social worker and nurse coordinator to discuss the risks and benefits of fetal intervention. Potential risks of fetal intervention include the following^[20]:

Preterm labor
Uterine disruption
Rupture of membranes
Chorioamnionitis
Side effects of tocolytics (used to prevent preterm labor)
Maternal pulmonary edema
Fetal demise

Additional risks of fetal surgery include bleeding, need for blood transfusion, and wound infection.

Preprocedural Planning

An experienced operative team is essential and usually includes the following^[20]:

Two pediatric surgeons
Perinatologist
Ultrasonographer/echocardiographer
Experienced operating room personnel
Pediatric/obstetric anesthesiologist

The team should also have blood products prepared for potential intraoperative transfusion. Patients needing fetal intervention usually have highly vascular solid tumors, which were shown to have increased transfusion requirements in a retrospective study that evaluated 112 cases of operative management of sacrococcygeal teratoma (SCT), including six in-utero repairs.^[52]

Open fetal surgery and ex-utero intrapartum treatment procedure

The following are used for maternal perioperative monitoring in open fetal surgery and the ex-utero intrapartum treatment (EXIT) procedure:

Blood pressure cuff
Large-bore intravenous (IV) catheters
Bladder catheter
Electrocardiographic (ECG) leads
Sequential compression devices
Pulse oximeter

Also necessary for open fetal procedures are the following:

Intraoperative ultrasound device
Uterine stapler
Large ring retractor
Sterile neonatal pulse oximeter and IV catheter for the fetus
Fluid warmer
Sterile neonatal laryngoscope and endotracheal tube (for the EXIT procedure)

Minimally invasive techniques

Equipment for minimally invasive techniques includes the following:

Intraoperative ultrasound device
LeVeen radiofrequency probe (8 prong) for radiofrequency ablation (RFA)
Fetoscope (1.9 mm, 60°) for laser ablation
Neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser fiber (0.4 mm) for laser ablation

Patient Preparation

Patients are usually admitted to the obstetric ward the evening before fetal surgery. Preoperatively, indomethacin, magnesium sulfate, or both are given to prevent uterine contraction during the procedure, and antibiotics are given prophylactically to prevent infection.

Anesthesia

Anesthesia for open fetal surgery includes maternal epidural and general anesthesia. This provides anesthesia to both the mother and the fetus and ensures uterine relaxation during the procedure.^{[20, 53]} Volatile anesthetics can cross the placenta and decrease fetal cardiac function; maternal anesthesia with IV nitroglycerin and/or epidural anesthesia can limit the amount of volatile anesthetic required.^[54] Epidural anesthesia also decreases uterine contractions during the postoperative recovery period.

Anesthesia options for minimally invasive techniques can range from spinal anesthesia with local anesthetic to general anesthesia, depending on the patient and the circumstances for fetal intervention. During the procedure, intramuscular injection of pain medication and a paralytic agent can be administered to the mother under ultrasonographic (US) guidance.^[55]

In a systematic review of anesthetic techniques for fetal operative procedures, 168 studies up to December 2021 demonstrated no difference in perioperative outcomes between maternal-only anesthesia (MA) and maternal-and-fetal anesthesia (MFA)^[56]; however, evaluation of open fetal surgery cases (including open fetal SCT resection) identified increased rates of premature rupture of membranes (PROM) and fetal death in cases using MFA. The agents most commonly used for fetal anesthesia are fentanyl, atropine, and curare paralytic agents (vecuronium or pancuronium).^[56]

Positioning

The mother is placed in a supine position on the operating room table, with the right side elevated to decrease the pressure of the uterus on the inferior vena cava (IVC).^[20]

Monitoring & Follow-up

Depending on the postoperative course, patients can be discharged within a week after fetal surgery, though they will need to stay at a facility near the fetal treatment center. Activity is gradually modified if there is minimal uterine irritability. US is performed twice a week to assess fetal development and resolution of hydrops. Because of the location of the hysterotomy, the mother will require cesarean delivery for all future deliveries.

Technique

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Media Gallery

Gravid uterus is exposed through Pfannenstiel incision. Media file courtesy of Dr Douglas Miniati and Dr Payam Saadai, Division of Pediatric Surgery, University of California, San Francisco, School of Medicine.
Intraoperative ultrasonography is used to mark extent of placenta and position of fetus prior to hysterotomy. Media file courtesy of Dr Douglas Miniati and Dr Payam Saadai, Division of Pediatric Surgery, University of California, San Francisco, School of Medicine.
Specially designed uterine stapler provides hemostasis and prevents separation of membranes during hysterotomy. Media file courtesy of Dr Douglas Miniati and Dr Payam Saadai, Division of Pediatric Surgery, University of California, San Francisco, School of Medicine.
Pulse oximeter is placed on foot of fetus to ensure fetal well-being. Media file courtesy of Dr Douglas Miniati and Dr Payam Saadai, Division of Pediatric Surgery, University of California, San Francisco, School of Medicine.
Intravenous access is established in saphenous vein of fetus before debulking of sacrococcygeal teratoma. Media file courtesy of Dr Douglas Miniati and Dr Payam Saadai, Division of Pediatric Surgery, University of California, San Francisco, School of Medicine.
Sacrococcygeal teratoma is exteriorized and is intimately involved with anus. Red rubber catheter can be inserted into anus to help identify rectum and prevent or identify iatrogenic injury. Media file courtesy of Dr Douglas Miniati and Dr Payam Saadai, Division of Pediatric Surgery, University of California, San Francisco, School of Medicine.