Patient Education and Consent
Given that the progression of cervical masses varies, counseling parents is challenging. Masses identified early in gestation associated with hydrops carry a high risk of fetal demise, and patient counseling is of paramount importance. Patients who have masses that progress rapidly, constricting the trachea and esophagus, and who survive to a viable gestation should be offered an ex-utero intrapartum treatment (EXIT)-to-delivery procedure. Counseling should also include discussion of the fetal risk associated with EXIT-to-delivery, which may include cardiorespiratory failure, asphyxia, prematurity, mass rupture, and pneumothorax.
From a maternal standpoint, depending on placental location, a classic hysterotomy may be required, prohibiting the possibilities of future vaginal deliveries. Additionally, the risk of uterine dehiscence and rupture in subsequent pregnancies is not trivial; such events have been reported to occur after 14% of EXIT procedures. [14] Therefore, all mothers should be counseled with regard to the associated risks.
Preprocedural Planning
The EXIT procedure requires careful planning with a multidisciplinary team that typically includes two pediatric/fetal surgeons, one obstetrician, one neonatologist, one ultrasonographer, one otolaryngologist, and one nurse scrub. In view of the risk that the fetus will require a tracheostomy during an EXIT procedure, the multidisciplinary team needs to be prepared to perform additional high-risk procedures if necessary to establish an airway. To ensure maternal safety during the procedure, adequate attention to uterine relaxation is paramount. Additionally, the multidisciplinary team should be prepared for the need for additional surgical procedures (eg, mass removal).
Equipment
A direct laryngoscope, rigid and flexible bronchoscopes, and a tracheostomy kit should be immediately available. Case reports have demonstrated the use of a video laryngoscope to assist with visualizing the vocal cords and prevent the need for tracheostomy when oral intubation cannot be performed with direct laryngoscopy. [15, 16]
A uterine stapler with absorbable staples (US Surgical Corporation, Norwalk, CT) is used to minimize blood loss during the hysterotomy.
Patient Preparation
Anesthesia
Inhaled anesthetics, particularly isoflurane, [17, 18] are necessary for uterine relaxation and uteroplacental gas exchange, which have been demonstrated to be normal up to 54 minutes on uteroplacental support during EXIT delivery. [19]
Alpha-adrenergic agonists are frequently required to maintain maternal blood pressure, given that high levels of isoflurane, which are needed for uterine relaxation, often result in hypotension.
In addition, nitroglycerin can assist with uterine relaxation. Activation of guanylyl cyclase leads to increased levels of cyclic guanosine monophosphate (cGMP) and decreased levels of intracellular calcium, resulting in uterine relaxation. [20] Typically, a fetal cocktail consisting of a paralytic and a narcotic is injected into the fetus intramuscularly.
Positioning
The patient is typically placed in the supine position on the operating room table. Occasionally, the patient may be placed in a lithotomy position to increase the space available to operating room staff.
Monitoring & Follow-up
After birth, follow-up computed tomography (CT) or magnetic resonance imaging (MRI) should be performed to confirm the diagnosis. Surgical management can be elective once an airway is established.
Postnatal management depends on the type, size, and location of the lesion. Cervical teratomas are frequently resected in the neonatal period to minimize the risk of malignant transformation. Because these lesions may involve the thyroid gland, care should be taken during the dissection, and consultation with an endocrinologist for hypothyroidism may be required postoperatively. Vascular malformations are frequently managed medically, whereas lymphatic malformations benefit from sclerotherapy, surgical resection, or both.
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Cervical Teratoma in an infant delivered via EXIT procedure
