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A Review of Fetal Thoracoamniotic and Vesicoamniotic Shunt Procedures
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A Review of Fetal Thoracoamniotic & Vesicoamniotic Shunt Procedures Casey L. Gregory, Jane Wright, Jessica Schwarz, and Laura Rakowski
Correspondence Casey L. Gregory BS, RDMS, Center for Fetal Diagnosis and Treatment, The Children’s Hospital of Philadelphia, 34th Street & Civic Center Boulevard, Philadelphia, PA 19104. [email protected]
ABSTRACT Fetal anomalies such as lower urinary tract obstructions and fluid-filled space-occupying lesions in the fetal chest can result in severe morbidity or mortality if left untreated. In-utero fetal shunt placement offers the potential to improve outcomes in infants with these conditions. The role of the nurse is paramount in the clinical and psychosocial management of the mother and family.
JOGNN, 00, 1-8; 2012. DOI: 10.1111/j.1552-6909.2012.01354.x Accepted November 2011
Keywords vesicoamniotic/thoracoamniotic vesicocentesis obstructive uropathy or lower urinary tract obstructions (LUTO) amnioinfusion macrocystic congenital adenomatoid malformation CCAM hydrops preeclampsia or maternal mirror syndrome
Casey L. Gregory, BS, RDMS, is a registered diagnostic medical sonographer at the Center for Fetal Diagnosis and Treatment, The Children’s Hospital of Philadelphia, Philadelphia, PA. Jane Wright RN, RDMS, is a perinatal nurse sonographer at the Center for Fetal Diagnosis and Treatment, Children’s Hospital of Philadelphia, Philadelphia, PA. Jessica Schwarz, CNM, MSN, works in the Special Delivery Unit, Center for Fetal Diagnosis and Treatment, Children’s Hospital of Philadelphia, Philadelphia, PA.
he advent of improved diagnostic imaging techniques such as fetal ultrasound, fetal echocardiography, fetal Doppler assessment, and fetal ultrafast magnetic resonance imaging (MRI) has resulted in earlier and more accurate prenatal diagnoses of fetal anomalies. These improvements and the increased availability of real-time ultrasound technology have contributed to the development of a growing number of fetal therapies, including several forms of ultrasound-guided percutaneous fetal therapy. The placement of a fetoamniotic shunt to decompress fluid-filled space-occupying lesions in the fetal chest or to temporize an obstructive uropathy represents examples of such therapy. It is important for nurses who care for patients undergoing this type of fetal therapy to be knowledgeable about the relevant diagnoses, the treatment options available, the risks and benefits of the procedure, and the ongoing care of the mother and fetus or neonate.
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The authors report no conflict of interest or relevant financial relationships.
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Obstructive Uropathy Genitourinary tract obstructions are among the most common congenital anomalies occurring in
1% of pregnancies. Fortunately, only about 1 in 500 pregnancies has significant urologic malformations (Biard et al., 2005). Fetal obstructive uropathies have a variety of etiologies and manifestations. Typically, these lower urinary tract obstructions (LUTO) involve the male fetus with an obstruction at the level of the proximal urethra. Vesicoamniotic shunting provides a temporary therapy to the fetus by allowing for a diversion of the fetal urine into the amniotic fluid space, thereby relieving the urine backup that causes kidney damage and preventing severe oligohydramnios and its sequelae pulmonary hypoplasia.
Pathophysiology Varieties of structural abnormalities including urethral atresia, posterior urethral valves that form excess flaps of tissue in the uretha, or “prune belly” syndrome cause LUTO. Prune belly syndrome, also known as TRIAD syndrome or EagleBarrett syndrome, is a group of defects including deficiency of abdominal muscle, undescended testes, and an abnormal, expanded bladder. Other anomalies that have been associated with
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A Review of Fetal Thoracoamniotic & Vesicoamniotic Shunt Procedures
LUTO include anterior urethral valves, meatal stenosis, and narrow hypoplastic mid-urethra. Cloacal developmental abnormalities, occurring primarily in female fetuses, are often associated with syndromic conditions that have not shown benefit from fetal therapy. Chromosomal aneuploidy such as Trisomy 21 and Trisomy 18 and a number of other genetic abnormalities have also been associated with LUTO.
Ultrasound examination of the fetal bladder is performed prior to and immediately following drainage by fine needle vesicocentesis. Vesicocentesis is an ultrasound guided, transabdominal procedure to aspirate urine from the fetal bladder. Careful visualization with ultrasound minimizes trauma to the fetus and helps to avoid the placenta, umbilical cord, and umbilical arteries that run parallel to the fetal bladder.
Complete obstruction of the urethra in early gestation often leads to hydronephrosis, massive bladder distention, and severe renal fibrocystic dysplasia. The lack of communication between the fetal bladder and the amniotic space results in oligo- or anhydramnios, leading to pulmonary hypoplasia and secondary deformations of the face and extremities (Wu & Johnson, 2009). The most critical component in neonatal survival is pulmonary development. Urethral obstruction in combination with early midgestation oligohydramnios carries a poor prognosis with reported mortality rates as high as 95% (Wilson & Johnson, 2003).
A comprehensive fetal ultrasound examination rules out the presence of other congenital anomalies and syndromic conditions. Neural tube defects and cardiac anomalies occur at a higher frequency with LUTO. Detailed evaluation can be extremely limited when oligohydramnios (absent or low amniotic fluid) is present. Amnioinfusion (injection of sterile saline into the amniotic cavity) may allow for better visualization of the fetus to help rule out associated anomalies (Wu & Johnson, 2009).
Prenatal Evaluation
Laura Rakowski, RN, is a registered nurse, Clinical Level 3 in the Newborn/Infant Intensive Care Unit, Children’s Hospital of Philadelphia, Philadelphia, PA.
Three techniques can be used for antenatal evaluation for LUTO: high-resolution sonographic survey to rule out additional congenital anomalies that might contribute to poor long-term survival, fetal karyotyping, and renal function analysis. In addition to identifying any concomitant anomalies, the sonographic survey evaluates the fetal kidneys, comparing size and echotexture. Long axis measurements help to determine the degree of urinary obstruction and hydronephrosis, whereas renal brightness (echogenicity) or visualization of small cystic areas suggests a degree of renal dysplasia. Long axis measurements that are small for gestational age in association with brighter appearing outer capsule (renal cortex) are associated with poor underlying function. The presence of cortical cysts (black hole ultrasonic appearance) is associated with irreversible, advanced renal damage. Intervention is not beneficial and contraindicated in the presence of cortical cysts. The visualization of fetal ureters determines the obstructive level. The presence of massive hydronephrosis without hydroureter (fluid-filled ureter) or an enlarged bladder indicates that the obstruction is at the level of the ureteropelvic junction (UPJ). A fetus with a complete or high grade UPJ does not have an enlarged bladder, therefore, vesicoamniotic shunting is contraindicated.
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The fetal karyotype is another essential component of the prenatal evaluation. In-utero shunt therapy does not improve prognosis for female fetuses that have cloacal malformations or chromosomal abnormalities. Early-onset severe oligohydramnios is a common feature in most cases of obstructive uropathy. For these fetuses, amniocentesis is not feasible, and a transabdominal chorionic villus sampling is the approach of choice. The final step in the prenatal assessment of fetal obstructive uropathies is renal function evaluation. Fetal vesicocentesis to evaluate renal function analysis is necessary, and sequential analysis of the fetal urine provides information regarding the degree of renal impairment and the likelihood of improvement with intervention. After vesicocentesis, fetal urine specimens are analyzed for total protein, sodium, chloride, calcium, osmolality, and β2-microglobulin levels (see Table 1).
Fetal Thoracoamniotic Shunt Space-occupying lesions such as congenital cystic adenomatoid malformations (CCAMS) and large pleural effusions, regardless of the etiology, can result in severe morbidity and mortality related to polyhydramnios, pulmonary hypoplasia, and hydrops. Episodic or one-time in-utero fineneedle aspiration of these fluid-filled lesions may benefit a select number of patients. However, longterm drainage with the insertion of a thoracoamniotic shunt is an alternate approach in the treatment of large effusions and macrocystic CCAMs
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Gregory, C. L., Wright, J., Schwarz, J., and Rakowski, L.
Table 1: Prognostic Urine Values for Selection of Fetuses for Prenatal Interventiona Good Prognosis
Poor Prognosis
Sodium
<90 mmol/L
>100 mmon/L
Chloride
<80 mmol/L
>90 mmon/L
Osmolality
<180 mOsm/L
>200 mOsm/L
Calcium
<7 mg/dl
>8 mg/dl
Total protein
<20 mg/dl
>40 mg/dl
β2 −Microglobulin
<6 mg/L
>10 mg/L
a Based on the last urine specimen obtained by serial bladder drainage (x3 or x4) at 24–48 h intervals between 18 and 22 weeks of gestation (Wilson & Johnson, 2003).
that rapidly recur after drainage. Chronic drainage can resolve polyhydramnios, reduce the risk of preterm labor, reverse fetal hydrops, and allow for normal lung growth.
Fetal Hydrothorax and Congenital Cystic Adenomatoid Malformation (CCAM) Pathophysiology. Fetal hydrothorax, that is, severe pleural effusions, may present as an isolated finding or as a component in generalized fluid
retention (hydrops). Structural malformations of the lymphatic system can cause isolated or primary fetal hydrothorax. Primary hydrothorax is rare with the incidence reported to be approximately 1 in 12,000 (Wilson et al., 2004). Secondary fetal hydrothorax, which is associated with immune or nonimmune hydrops, may be due to a wide variety of maternal and fetal disorders including infection, cardiac defects, anemia, malformations of the placenta and umbilical cord, and aneuploidy (abnormal number of chromosomes) (Keswani, Wilson, & Johnson, 2006). Congenital cystic adenomatoid malformation is a benign cystic lung mass that is usually restricted to one lobe of the lung (Adzick & Kitano, 2003) but can occur bilaterally in approximately 2% of cases (see Figure 1). The precise incidence is unknown because more than two thirds of neonates with CCAMs have no symptoms at birth. Sonographic imaging in utero has increased detection rates, but clinically significant CCAMs remain rare. The overgrowth of the terminal respiratory bronchioles that form the cysts of varying sizes from less than 1mm to greater then 10cm can be ultrasonically visualized (Adzick & Kitano). Congenital cystic adenomatoid malformation is classified by appearance on ultrasound as either microcystic
Figure 1. Sonographic image of a macrocystic congenital cystic adenomatoid malformations (CCAM) (right arrow) prior to thoracoamniotic shunt procedure.
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Fluid-filled lung lesions and large pleural effusions threaten the developing fetus by acting as space-occupying masses in the fetal thorax that impair pulmonary development.
or macrocystic (Callen, 2007). Only fetuses with macrocystic CCAMs are candidates for treatment by thoracoamniotic shunting of their large, fluidfilled, cystic component. Fluid-filled, cystic lung lesions or large pleural effusions pose a threat to the developing fetus by acting as space-occupying masses in the fetal chest. This mass causes intrathoracic compression of fetal lung tissue that depending on the size of the lesion and the gestational age at which this occurs (18–24 weeks gestation) may result in impaired pulmonary development. Later in gestation, large fluid collections may result in compression of the fetal esophagus that decrease or inhibit fetal swallowing of amniotic fluid resulting in polyhydramnios. Polyhydramnios has an associated risk of preterm labor. In addition, increased intrathoracic pressure may impair venous return of intrathoracic blood and cause mediastinal shift of the heart and great vessels. This mediastinal shift may further compromise the fetal hemodynamic state leading to the development of nonimmune hydrops. If left untreated, large fluid-filled compartments can lead to significant morbidity and mortality in the fetus and mother. The development of fetal hydrops and associated placentomegaly can lead to maternal mirror syndrome, a potentially lifethreatening illness in which the maternal condition begins to mirror the fetal illness. The mother develops progressive symptoms of preeclampsia including proteinuria, hypertension, peripheral edema, and risk for life-threatening pulmonary and cerebral edema (Bianchi, Crombleholme, D’Alton, & Malone, 2010). Delivery is the only treatment option for maternal mirror syndrome. Prenatal Evaluation. The antenatal evaluation of the patient with a fetal pleural effusion or CCAM includes a comprehensive fetal ultrasound to identify any concomitant abnormalities and to characterize the nature and size of the lesion as well as its effect on the fetus. On ultrasound, a pleural effusion (which may be unilateral or bilateral) will appear as a black collection of fluid within the thorax surrounding normal lung tissue (shades of gray) that usually conforms to the normal chest contour. Depending on the severity of the effusion,
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other findings on ultrasound include compression of normal lung tissue, cardiac shift and compression, and flattening or eversion of the diaphragm and evidence of hydrops (Callen, 2007). A macrocystic CCAM appears on ultrasound as an echogenic (bright) mass containing a large dominant cyst or multiple macrocysts. The volume of the CCAM is measured and compared to the fetal head circumference. This ratio is known as the CCAM volume ratio (CVR). A CVR of >1.6 indicates a fetus at increased risk for the development of fetal hydrops. The need for shunting is determined not by CVR alone but by the degree of fetal and maternal compromise. Initial treatment for pleural effusion and CCAM involves fine-needle drainage of the fluid component of the mass. A very low risk of aneuploidy in isolated CCAMs has been reported (Staebler et al., 2005), but the risk is 5.8% with primary pleural effusions (Achiron, Weissman, Lipitz, Mashiach, & Goldman, 1995).Therefore, amniocentesis for karyotype is strongly recommended for all patients prior to shunt placement. Effusion fluid should be evaluated for cell count and infectious studies, if not already reported. Primary hydrothorax is confirmed by a microscopic exam of aspirated fluid from the effusion that will show a predomination (> 95%) of lymphocytes and monocytes. The success of a thoracoamniotic shunt as a treatment option depends on the diagnosis and the severity of the fetal condition based on signs of nonimmune hydrops including skin edema, scalp edema, and ascites. Worsening hydrops or rapid reaccumulation of pleural fluid or cystic component of the CCAM after drainage are indications for shunting (see Figure 2).
Shunt Procedure As for any surgical procedure, a standard presurgery history and physical and informed consent should occur prior to fetoamniotic shunt placement. Preprocedure instructions include nothing by mouth for eight hours prior to the expected time of the procedure. Assessment of fetal well-being and uterine activity with an electronic fetal monitor prior to procedure is needed. Peripheral intravenous access is established, and a complete blood count and blood type with antibody screen are assayed preprocedure. Indomethacin (50mg) is given orally one hour prior to procedure for peri-operative tocolysis.
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Thoracoamniotic and vesicoamniotic shunt procedures should be performed in a setting that allows for airway management and continuous maternal assessment. Anesthesia staff must remain present throughout the procedure. Sedation agents utilized may include morphine sulfate, valium, midazolam, propofol, and remifentanil. These agents cause fetal quiescence as well as maternal sedation. The patient should be positioned on a procedure table in lateral tilt to optimize placental perfusion. Following standard operative prep and draping, the placental location and fetal position are identified with sterile intraoperative ultrasound. Under local anesthesia, the maternal abdomen is incised, and continuous ultrasound provides guidance for the insertion of the shunt trocar through the maternal abdomen, uterine wall, amniotic sac, and into the fluid-filled space (bladder, effusion, or cystic mass) where the shunt is deployed (see Figure 3). Throughout the procedure, continuous ultrasound guidance is essential. Steri-strips along with a Tegaderm or a Band-Aid are used to close the abdominal incision. For 4 hours postprocedure, uterine activity is continually assessed. In addition, continuous fetal heart rate monitoring is necessary if the fetal age is greater than 24 weeks gestation. Maternal vital
Vesicoamniotic shunting provides temporary therapy by allowing for a diversion of the fetal urine into the amniotic fluid but does not repair the underlying uropathy.
signs are monitored per institutional postanesthesia care guidelines. Discharge occurs when the woman has recovered from sedation, is able to tolerate oral fluids, and voids spontaneously. The nurse should instruct the woman to restrict activity until her follow-up assessment and provide a prescription for 10 days of prophylactic oral antibiotic therapy. The woman usually returns for follow-up evaluation and repeat ultrasound in 2 to 3 days and again at one-week postoperative to assess shunt placement, function and drainage, and amniotic fluid volume. Followup ultrasound assessments also screen for evidence of fetal membrane separation and confirm fetal well-being status. Ultrasound visualization for evidence of resolving hydrops and continued decompression of the fluid-filled component is important. On ultrasound, thoraco- and vesicoamniotic shunts are easily visualized and appear as two parallel echogenic white lines. Correct placement is documented by visualizing the shunt as it
Figure 2. Sonographic image of a thoracoamniotic shunt (arrows). The shunt extends from the fetal chest through the fetal wall into the amniotic space.
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Figure 3. The fetal shunt (top) is hollow, coiled (pigtail) and provides one-way fluid drainage to the amniotic space. Trocar used for insertion into the fetus (below).
traverses the fetal chest or abdominal wall into the amniotic sac to the decompressed cystic cavity or urinary bladder. The frequency of subsequent ultrasound assessment is determined based on maternal and fetal condition.
Complications Dislodgment of the shunt from the bladder or thoracic wall is the most common complication of fetoamniotic placement (Keswani et al., 2006). Particulate matter within the cystic space or thrombus formation from bleeding into the fluid filled space can result in obstruction of the shunt. Reinsertion of the shunt may be required if dislodgement or obstruction, reaccumulation of the cystic or pleural fluid, or excessive fetal urine within the bladder occur. Additional complications resulting from shunt insertion may include preterm labor, preterm delivery, premature rupture of membranes, chorioamnionitis, chorioamniotic membrane separation, or bleeding. The pregnancy loss rate following of shunt placement is approximately 5% (Fleischer, Toy, Lee, Manning, & Romero, 2011).
Birth Planning and Care of the Neonate Birth of an infant who has a fetoamniotic shunt should occur at a tertiary care center. The presence of a fetoamniotic shunt is not a contraindication to vaginal birth, and careful prenatal evaluation of the maternal/fetal dyad will dictate the
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safest method. In all cases, standard resuscitative equipment should be available at the time of birth, and the team should follow the current neonatal resuscitation procedural guidelines. Women with pregnancies that have undergone in-utero fetal shunting typically give birth at 34 to 35 weeks gestation. Therefore, depending on gestational age at delivery, the neonatal team may need to anticipate some degree of respiratory distress at birth and should have surfactant available. Care of Neonate Requiring a Chest Shunt. If the thoracoamniotic shunt was successful in draining the lesion, the likelihood of neonatal respiratory distress at birth is unusual. Barring any maternal contraindications, a vaginal birth may be appropriate. Birth by ex-utero intrapartum therapy (EXIT) may be necessary in select fetal lung lesion cases based on the degree of mediastinal shift caused by the lesion and the expectation for respiratory compromise at the time of birth. The EXIT procedure is a highly specialized cesarean performed by a multidisciplinary team. During a cesarean birth, an EXIT procedure is performed on the neonate where the umbilical cord is not severed and newborn remains attached to the placenta to provide continuous nutrient exchanges allowing for immediate neonatal surgery. The neonate receives oxygen via the placenta until the chest mass is removed and/or an airway with adequate ventilation is established
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(Howell, Burns, Lenghetti, Kerr, & Harkins, 2002). During thoracoamniotic shunt cases, the resuscitation team should be prepared to place chest tubes for pneumothorax or effusion drainage. When the infant is born, the fetal chest shunt is immediately clamped, carefully removed, and a sterile occlusive dressing is applied at the site to minimize the chance of pneumothorax prior to the infant’s first breath. As shunt displacement is common, providers should anticipate the possibility that the infant may be born without the shunt in place. In such cases, the shunt site is immediately covered with a sterile occlusive dressing. A chest X-ray is obtained as soon as possible to determine the need for a chest tube if oxygenation of the newborn is poor. Newborns are then transported to the neonatal intensive care unit for ongoing monitoring of respiratory status. If the infant is mechanically ventilated, ongoing evaluation of ventilator settings, blood gases and chest X-rays will be required. A pediatric surgeon should be available if emergent resection of the CCAM is necessary.
Care of Infant Requiring Bladder Shunt. Prevention of pulmonary hypoplasia and renal dysplasia are the goals of prenatal treatment of lower urinary tract obstructions. Limited information is available about long-term outcomes of bladder shunting inutero. Prior to birth, the need for ventilation and surfactant therapy should be anticipated due to the history of oligohydramnios or preterm birth. If the bladder shunt is inserted at birth, it should be left in place until a pediatric urologist can evaluate the infant. Depending on the neonate’s disease process, the bladder shunt may continue to facilitate drainage until a Foley catheter or vesicostomy is inserted. Febrile urinary tract infections, reflux, and residual bladder dysfunction may exacerbate preexisting prenatal renal injury (Biard et al., 2005). To evaluate renal injury, long-term renal function measurements and urologic studies such as a voiding cystourethrogram will be necessary to tailor therapy for each individual infant. The total length of neonatal hospitalization is highly variable and is dependent upon a number of factors including the underlying abnormality, the success of the prenatal intervention in treating the abnormality, and the gestational age at delivery. Factors that lengthen the hospital stay may include prematurity, need for ventilatory support, infection, the need for surgical intervention, and delayed feeding.
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Delivery of an infant who has a fetoamniotic shunt should occur in a tertiary care center.
The Nurse’s Role The prenatal diagnosis of a fetal anomaly is associated with increased stress for pregnant women and their families. Pregnancies diagnosed with pleural effusion or CCAM, further complicated by nonimmune hydrops, are at significantly higher risk for fetal and neonatal morbidity and mortality. Perinatal nurses require education about these diagnoses and how best to provide ongoing psychological and emotional support to these special families. The diagnosis of a fetal anomaly destroys the dream of the perfect infant, and women and their families should be supported while they adapt to the reality of the new child. Emotional stress interferes with a woman’s understanding of all the information she receives during the initial counseling. The nurse should be prepared to review information about the diagnosis, prognosis, treatment options, and planned management multiple times with the woman and her family to ensure understanding of the issues involved. Counseling pregnant women undergoing thoraco/vesicoamniotic shunt placement about the fetal and maternal risks and complications of the procedure and obtaining informed consent is important. Research has shown that parents may misunderstand terminology used in antenatal counseling about fetal anomalies, may perceive the counseling they receive as biased, and may receive conflicting or erroneous information from numerous health care providers (Chitty, Barnes, & Berry, 1996). Nurses need to assess the woman’s level of understanding, and as needed solicit further physician involvement in the provision of appropriate information. Some families may also need additional help from a social worker to address and help with financial needs such as housing while they are undergoing procedures or receiving prenatal care. The referring maternal fetal medicine physician may continue surveillance on discharged women. Ongoing communication between providers is important to coordinate care and optimize outcomes. Following the shunt intervention, the woman and family require continuing education related to activity restriction, antibiotic use, signs and symptoms of preterm labor, rupture of membranes and
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other potential complications, and follow-up appointments.
prenatal vesicoamniotic shunting for lower urinary tract obstruction. Obstetrics and Gynecology, 106 (3), 503–508. Callen, P. W. (2007). Ultrasound evaluation of the fetal thorax. In P.W. Callen (ed.). Ultrasonography in obstetrics and gynecology (5th ed., pp. 340, 343). Philadelphia, PA: W.B. Saunders.
Summary
Chitty, L., Barnes, C., & Berry, C. (1996). Continuing with pregnancy
The role of fetal therapy is to optimize outcomes for the fetus with a lower urinary tract obstruction, congenital pleural effusion, or macrocystic CCAM with the utilization of a fetoamniotic shunt. Prenatal screening as well as appropriate counseling that emphasizes the risks and long-term outcomes of successful and unsuccessful shunts procedures is essential. The perinatal nurse is optimally positioned to assess the family’s understanding of their neonate’s diagnosis and the treatment options available. Perinatal nurses play a crucial role in supporting the woman and her family throughout this experience.
after a diagnosis of lethal abnormality: experience of five couples and recommendations for management. British Medical Journal, 313 (7055), 478–480. Fleischer, A., Toy, E., Lee, W., Manning, F., & Romero, R. (eds.) (2011). Maternal fetal surgery and percutaneous ultrasound guided fetal therapy techniques. In Sonography in obstetrics and gynecology: Principles and practice (pp. 803–808). New York, NY: McGraw-Hill Prof Med/Tech. Howell, L. J., Burns, K. M., Lenghetti, E., Kerr, J. C., & Harkins, L. S. (2002). Management of fetal airway obstruction: an innovative strategy. MCN, The American Journal of Maternal Child Nursing, 27 (4), 238–244. Keswani, S. G., Wilson, R. D., & Johnson, M. P. (2006). Percutaneous intrauterine fetal shunting. In J. Apuzzio, A. Vintzileos, and L. Ifty (eds.). Operative Obstetrics ( 3rd ed., pp. 109–120). London, UK: Taylor & Francis Books. Staebler, M., Donner, C., Van Regemorter, N., Duprez, L., De Maertelaer, V., Devreker, F., & Avni, F. (2005). Should determination
REFERENCES
of the karyotype be systematic for all malformations detected
Achiron, R., Weissman, A., Lipitz, S., Mashiach, S., & Goldman,
by obstetrical ultrasound? Prenatal Diagnosis, 25 (7), 567–573.
B. (1995). Fetal pleural effusion: the risk of fetal trisomy. Gynecologic and Obstetric Investigation, 39 (3), 153–156.
holme, T, . . . Adzick, N. (2004). Thoracoamniotic shunts: fetal
doi:10.1159/000292399. Adzick, N., & Kitano, Y. (2003). Fetal surgery for lung lesions, congen-
treatment of pleural effusions and congenital cystic adenoma-
ital diaphragmatic hernia, and sacrococcygeal teratoma. Sem-
toid malformations. Fetal Diagnosis and Therapy, 19, 416–417.
inars in Pediatric Surgery, 12 (3), 154–167. doi:10.1016/s1055-
doi:10.1159/000078994. Wilson, R., & Johnson, M. (2003). Prenatal ultrasound guided percu-
8586(03)00030-1. Bianchi, D. W., Cromblehome, T. M., D’Alton, M. E., & Malone, F. D. (2010). Cystic adenomatoid malformation. In Fetology
(pp.
236–271).
New
York,
NY:
McGraw-Hill.
doi:10.1097/01.AOG.0000171117.38929.eb. Biard, J., Johnson, M., Carr, M., Wilson, R., Hedrick, H., Pavlock, C., & Adzick, N. (2005). Long-term outcomes in children treated by
8
doi:10.1002/pd.1187. Wilson, R., Baxter, J., Johnson, M., King, M., Kasperski, S., Cromble-
JOGNN, 00, 1-8; 2012. DOI: 10.1111/j.1552-6909.2012.01354.x
taneous shunts for obstructive uropathy and thoracic disease. Seminars in Pediatric Surgery, 12 (3), 182–189. Wu, S., & Johnson, M. (2009). Fetal lower urinary tract obstruction. trieved
Clinics
from
in
Perinatology,
36 (2),
377–390.
Re-
http://www.ncbi.nlm.nih.gov/pubmed/19559326
doi:10.1016/jclp.2009.03.010.
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A Review of Fetal Thoracoamniotic & Vesicoamniotic Shunt Procedures Casey L. Gregory, Jane Wright, Jessica Schwarz, and Laura Rakowski
Correspondence Casey L. Gregory BS, RDMS, Center for Fetal Diagnosis and Treatment, The Children’s Hospital of Philadelphia, 34th Street & Civic Center Boulevard, Philadelphia, PA 19104. [email protected]
ABSTRACT Fetal anomalies such as lower urinary tract obstructions and fluid-filled space-occupying lesions in the fetal chest can result in severe morbidity or mortality if left untreated. In-utero fetal shunt placement offers the potential to improve outcomes in infants with these conditions. The role of the nurse is paramount in the clinical and psychosocial management of the mother and family.
JOGNN, 00, 1-8; 2012. DOI: 10.1111/j.1552-6909.2012.01354.x Accepted November 2011
Keywords vesicoamniotic/thoracoamniotic vesicocentesis obstructive uropathy or lower urinary tract obstructions (LUTO) amnioinfusion macrocystic congenital adenomatoid malformation CCAM hydrops preeclampsia or maternal mirror syndrome
Casey L. Gregory, BS, RDMS, is a registered diagnostic medical sonographer at the Center for Fetal Diagnosis and Treatment, The Children’s Hospital of Philadelphia, Philadelphia, PA. Jane Wright RN, RDMS, is a perinatal nurse sonographer at the Center for Fetal Diagnosis and Treatment, Children’s Hospital of Philadelphia, Philadelphia, PA. Jessica Schwarz, CNM, MSN, works in the Special Delivery Unit, Center for Fetal Diagnosis and Treatment, Children’s Hospital of Philadelphia, Philadelphia, PA.
he advent of improved diagnostic imaging techniques such as fetal ultrasound, fetal echocardiography, fetal Doppler assessment, and fetal ultrafast magnetic resonance imaging (MRI) has resulted in earlier and more accurate prenatal diagnoses of fetal anomalies. These improvements and the increased availability of real-time ultrasound technology have contributed to the development of a growing number of fetal therapies, including several forms of ultrasound-guided percutaneous fetal therapy. The placement of a fetoamniotic shunt to decompress fluid-filled space-occupying lesions in the fetal chest or to temporize an obstructive uropathy represents examples of such therapy. It is important for nurses who care for patients undergoing this type of fetal therapy to be knowledgeable about the relevant diagnoses, the treatment options available, the risks and benefits of the procedure, and the ongoing care of the mother and fetus or neonate.
T
(Continued)
The authors report no conflict of interest or relevant financial relationships.
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Obstructive Uropathy Genitourinary tract obstructions are among the most common congenital anomalies occurring in
1% of pregnancies. Fortunately, only about 1 in 500 pregnancies has significant urologic malformations (Biard et al., 2005). Fetal obstructive uropathies have a variety of etiologies and manifestations. Typically, these lower urinary tract obstructions (LUTO) involve the male fetus with an obstruction at the level of the proximal urethra. Vesicoamniotic shunting provides a temporary therapy to the fetus by allowing for a diversion of the fetal urine into the amniotic fluid space, thereby relieving the urine backup that causes kidney damage and preventing severe oligohydramnios and its sequelae pulmonary hypoplasia.
Pathophysiology Varieties of structural abnormalities including urethral atresia, posterior urethral valves that form excess flaps of tissue in the uretha, or “prune belly” syndrome cause LUTO. Prune belly syndrome, also known as TRIAD syndrome or EagleBarrett syndrome, is a group of defects including deficiency of abdominal muscle, undescended testes, and an abnormal, expanded bladder. Other anomalies that have been associated with
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A Review of Fetal Thoracoamniotic & Vesicoamniotic Shunt Procedures
LUTO include anterior urethral valves, meatal stenosis, and narrow hypoplastic mid-urethra. Cloacal developmental abnormalities, occurring primarily in female fetuses, are often associated with syndromic conditions that have not shown benefit from fetal therapy. Chromosomal aneuploidy such as Trisomy 21 and Trisomy 18 and a number of other genetic abnormalities have also been associated with LUTO.
Ultrasound examination of the fetal bladder is performed prior to and immediately following drainage by fine needle vesicocentesis. Vesicocentesis is an ultrasound guided, transabdominal procedure to aspirate urine from the fetal bladder. Careful visualization with ultrasound minimizes trauma to the fetus and helps to avoid the placenta, umbilical cord, and umbilical arteries that run parallel to the fetal bladder.
Complete obstruction of the urethra in early gestation often leads to hydronephrosis, massive bladder distention, and severe renal fibrocystic dysplasia. The lack of communication between the fetal bladder and the amniotic space results in oligo- or anhydramnios, leading to pulmonary hypoplasia and secondary deformations of the face and extremities (Wu & Johnson, 2009). The most critical component in neonatal survival is pulmonary development. Urethral obstruction in combination with early midgestation oligohydramnios carries a poor prognosis with reported mortality rates as high as 95% (Wilson & Johnson, 2003).
A comprehensive fetal ultrasound examination rules out the presence of other congenital anomalies and syndromic conditions. Neural tube defects and cardiac anomalies occur at a higher frequency with LUTO. Detailed evaluation can be extremely limited when oligohydramnios (absent or low amniotic fluid) is present. Amnioinfusion (injection of sterile saline into the amniotic cavity) may allow for better visualization of the fetus to help rule out associated anomalies (Wu & Johnson, 2009).
Prenatal Evaluation
Laura Rakowski, RN, is a registered nurse, Clinical Level 3 in the Newborn/Infant Intensive Care Unit, Children’s Hospital of Philadelphia, Philadelphia, PA.
Three techniques can be used for antenatal evaluation for LUTO: high-resolution sonographic survey to rule out additional congenital anomalies that might contribute to poor long-term survival, fetal karyotyping, and renal function analysis. In addition to identifying any concomitant anomalies, the sonographic survey evaluates the fetal kidneys, comparing size and echotexture. Long axis measurements help to determine the degree of urinary obstruction and hydronephrosis, whereas renal brightness (echogenicity) or visualization of small cystic areas suggests a degree of renal dysplasia. Long axis measurements that are small for gestational age in association with brighter appearing outer capsule (renal cortex) are associated with poor underlying function. The presence of cortical cysts (black hole ultrasonic appearance) is associated with irreversible, advanced renal damage. Intervention is not beneficial and contraindicated in the presence of cortical cysts. The visualization of fetal ureters determines the obstructive level. The presence of massive hydronephrosis without hydroureter (fluid-filled ureter) or an enlarged bladder indicates that the obstruction is at the level of the ureteropelvic junction (UPJ). A fetus with a complete or high grade UPJ does not have an enlarged bladder, therefore, vesicoamniotic shunting is contraindicated.
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The fetal karyotype is another essential component of the prenatal evaluation. In-utero shunt therapy does not improve prognosis for female fetuses that have cloacal malformations or chromosomal abnormalities. Early-onset severe oligohydramnios is a common feature in most cases of obstructive uropathy. For these fetuses, amniocentesis is not feasible, and a transabdominal chorionic villus sampling is the approach of choice. The final step in the prenatal assessment of fetal obstructive uropathies is renal function evaluation. Fetal vesicocentesis to evaluate renal function analysis is necessary, and sequential analysis of the fetal urine provides information regarding the degree of renal impairment and the likelihood of improvement with intervention. After vesicocentesis, fetal urine specimens are analyzed for total protein, sodium, chloride, calcium, osmolality, and β2-microglobulin levels (see Table 1).
Fetal Thoracoamniotic Shunt Space-occupying lesions such as congenital cystic adenomatoid malformations (CCAMS) and large pleural effusions, regardless of the etiology, can result in severe morbidity and mortality related to polyhydramnios, pulmonary hypoplasia, and hydrops. Episodic or one-time in-utero fineneedle aspiration of these fluid-filled lesions may benefit a select number of patients. However, longterm drainage with the insertion of a thoracoamniotic shunt is an alternate approach in the treatment of large effusions and macrocystic CCAMs
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Gregory, C. L., Wright, J., Schwarz, J., and Rakowski, L.
Table 1: Prognostic Urine Values for Selection of Fetuses for Prenatal Interventiona Good Prognosis
Poor Prognosis
Sodium
<90 mmol/L
>100 mmon/L
Chloride
<80 mmol/L
>90 mmon/L
Osmolality
<180 mOsm/L
>200 mOsm/L
Calcium
<7 mg/dl
>8 mg/dl
Total protein
<20 mg/dl
>40 mg/dl
β2 −Microglobulin
<6 mg/L
>10 mg/L
a Based on the last urine specimen obtained by serial bladder drainage (x3 or x4) at 24–48 h intervals between 18 and 22 weeks of gestation (Wilson & Johnson, 2003).
that rapidly recur after drainage. Chronic drainage can resolve polyhydramnios, reduce the risk of preterm labor, reverse fetal hydrops, and allow for normal lung growth.
Fetal Hydrothorax and Congenital Cystic Adenomatoid Malformation (CCAM) Pathophysiology. Fetal hydrothorax, that is, severe pleural effusions, may present as an isolated finding or as a component in generalized fluid
retention (hydrops). Structural malformations of the lymphatic system can cause isolated or primary fetal hydrothorax. Primary hydrothorax is rare with the incidence reported to be approximately 1 in 12,000 (Wilson et al., 2004). Secondary fetal hydrothorax, which is associated with immune or nonimmune hydrops, may be due to a wide variety of maternal and fetal disorders including infection, cardiac defects, anemia, malformations of the placenta and umbilical cord, and aneuploidy (abnormal number of chromosomes) (Keswani, Wilson, & Johnson, 2006). Congenital cystic adenomatoid malformation is a benign cystic lung mass that is usually restricted to one lobe of the lung (Adzick & Kitano, 2003) but can occur bilaterally in approximately 2% of cases (see Figure 1). The precise incidence is unknown because more than two thirds of neonates with CCAMs have no symptoms at birth. Sonographic imaging in utero has increased detection rates, but clinically significant CCAMs remain rare. The overgrowth of the terminal respiratory bronchioles that form the cysts of varying sizes from less than 1mm to greater then 10cm can be ultrasonically visualized (Adzick & Kitano). Congenital cystic adenomatoid malformation is classified by appearance on ultrasound as either microcystic
Figure 1. Sonographic image of a macrocystic congenital cystic adenomatoid malformations (CCAM) (right arrow) prior to thoracoamniotic shunt procedure.
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A Review of Fetal Thoracoamniotic & Vesicoamniotic Shunt Procedures
Fluid-filled lung lesions and large pleural effusions threaten the developing fetus by acting as space-occupying masses in the fetal thorax that impair pulmonary development.
or macrocystic (Callen, 2007). Only fetuses with macrocystic CCAMs are candidates for treatment by thoracoamniotic shunting of their large, fluidfilled, cystic component. Fluid-filled, cystic lung lesions or large pleural effusions pose a threat to the developing fetus by acting as space-occupying masses in the fetal chest. This mass causes intrathoracic compression of fetal lung tissue that depending on the size of the lesion and the gestational age at which this occurs (18–24 weeks gestation) may result in impaired pulmonary development. Later in gestation, large fluid collections may result in compression of the fetal esophagus that decrease or inhibit fetal swallowing of amniotic fluid resulting in polyhydramnios. Polyhydramnios has an associated risk of preterm labor. In addition, increased intrathoracic pressure may impair venous return of intrathoracic blood and cause mediastinal shift of the heart and great vessels. This mediastinal shift may further compromise the fetal hemodynamic state leading to the development of nonimmune hydrops. If left untreated, large fluid-filled compartments can lead to significant morbidity and mortality in the fetus and mother. The development of fetal hydrops and associated placentomegaly can lead to maternal mirror syndrome, a potentially lifethreatening illness in which the maternal condition begins to mirror the fetal illness. The mother develops progressive symptoms of preeclampsia including proteinuria, hypertension, peripheral edema, and risk for life-threatening pulmonary and cerebral edema (Bianchi, Crombleholme, D’Alton, & Malone, 2010). Delivery is the only treatment option for maternal mirror syndrome. Prenatal Evaluation. The antenatal evaluation of the patient with a fetal pleural effusion or CCAM includes a comprehensive fetal ultrasound to identify any concomitant abnormalities and to characterize the nature and size of the lesion as well as its effect on the fetus. On ultrasound, a pleural effusion (which may be unilateral or bilateral) will appear as a black collection of fluid within the thorax surrounding normal lung tissue (shades of gray) that usually conforms to the normal chest contour. Depending on the severity of the effusion,
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other findings on ultrasound include compression of normal lung tissue, cardiac shift and compression, and flattening or eversion of the diaphragm and evidence of hydrops (Callen, 2007). A macrocystic CCAM appears on ultrasound as an echogenic (bright) mass containing a large dominant cyst or multiple macrocysts. The volume of the CCAM is measured and compared to the fetal head circumference. This ratio is known as the CCAM volume ratio (CVR). A CVR of >1.6 indicates a fetus at increased risk for the development of fetal hydrops. The need for shunting is determined not by CVR alone but by the degree of fetal and maternal compromise. Initial treatment for pleural effusion and CCAM involves fine-needle drainage of the fluid component of the mass. A very low risk of aneuploidy in isolated CCAMs has been reported (Staebler et al., 2005), but the risk is 5.8% with primary pleural effusions (Achiron, Weissman, Lipitz, Mashiach, & Goldman, 1995).Therefore, amniocentesis for karyotype is strongly recommended for all patients prior to shunt placement. Effusion fluid should be evaluated for cell count and infectious studies, if not already reported. Primary hydrothorax is confirmed by a microscopic exam of aspirated fluid from the effusion that will show a predomination (> 95%) of lymphocytes and monocytes. The success of a thoracoamniotic shunt as a treatment option depends on the diagnosis and the severity of the fetal condition based on signs of nonimmune hydrops including skin edema, scalp edema, and ascites. Worsening hydrops or rapid reaccumulation of pleural fluid or cystic component of the CCAM after drainage are indications for shunting (see Figure 2).
Shunt Procedure As for any surgical procedure, a standard presurgery history and physical and informed consent should occur prior to fetoamniotic shunt placement. Preprocedure instructions include nothing by mouth for eight hours prior to the expected time of the procedure. Assessment of fetal well-being and uterine activity with an electronic fetal monitor prior to procedure is needed. Peripheral intravenous access is established, and a complete blood count and blood type with antibody screen are assayed preprocedure. Indomethacin (50mg) is given orally one hour prior to procedure for peri-operative tocolysis.
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Thoracoamniotic and vesicoamniotic shunt procedures should be performed in a setting that allows for airway management and continuous maternal assessment. Anesthesia staff must remain present throughout the procedure. Sedation agents utilized may include morphine sulfate, valium, midazolam, propofol, and remifentanil. These agents cause fetal quiescence as well as maternal sedation. The patient should be positioned on a procedure table in lateral tilt to optimize placental perfusion. Following standard operative prep and draping, the placental location and fetal position are identified with sterile intraoperative ultrasound. Under local anesthesia, the maternal abdomen is incised, and continuous ultrasound provides guidance for the insertion of the shunt trocar through the maternal abdomen, uterine wall, amniotic sac, and into the fluid-filled space (bladder, effusion, or cystic mass) where the shunt is deployed (see Figure 3). Throughout the procedure, continuous ultrasound guidance is essential. Steri-strips along with a Tegaderm or a Band-Aid are used to close the abdominal incision. For 4 hours postprocedure, uterine activity is continually assessed. In addition, continuous fetal heart rate monitoring is necessary if the fetal age is greater than 24 weeks gestation. Maternal vital
Vesicoamniotic shunting provides temporary therapy by allowing for a diversion of the fetal urine into the amniotic fluid but does not repair the underlying uropathy.
signs are monitored per institutional postanesthesia care guidelines. Discharge occurs when the woman has recovered from sedation, is able to tolerate oral fluids, and voids spontaneously. The nurse should instruct the woman to restrict activity until her follow-up assessment and provide a prescription for 10 days of prophylactic oral antibiotic therapy. The woman usually returns for follow-up evaluation and repeat ultrasound in 2 to 3 days and again at one-week postoperative to assess shunt placement, function and drainage, and amniotic fluid volume. Followup ultrasound assessments also screen for evidence of fetal membrane separation and confirm fetal well-being status. Ultrasound visualization for evidence of resolving hydrops and continued decompression of the fluid-filled component is important. On ultrasound, thoraco- and vesicoamniotic shunts are easily visualized and appear as two parallel echogenic white lines. Correct placement is documented by visualizing the shunt as it
Figure 2. Sonographic image of a thoracoamniotic shunt (arrows). The shunt extends from the fetal chest through the fetal wall into the amniotic space.
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Figure 3. The fetal shunt (top) is hollow, coiled (pigtail) and provides one-way fluid drainage to the amniotic space. Trocar used for insertion into the fetus (below).
traverses the fetal chest or abdominal wall into the amniotic sac to the decompressed cystic cavity or urinary bladder. The frequency of subsequent ultrasound assessment is determined based on maternal and fetal condition.
Complications Dislodgment of the shunt from the bladder or thoracic wall is the most common complication of fetoamniotic placement (Keswani et al., 2006). Particulate matter within the cystic space or thrombus formation from bleeding into the fluid filled space can result in obstruction of the shunt. Reinsertion of the shunt may be required if dislodgement or obstruction, reaccumulation of the cystic or pleural fluid, or excessive fetal urine within the bladder occur. Additional complications resulting from shunt insertion may include preterm labor, preterm delivery, premature rupture of membranes, chorioamnionitis, chorioamniotic membrane separation, or bleeding. The pregnancy loss rate following of shunt placement is approximately 5% (Fleischer, Toy, Lee, Manning, & Romero, 2011).
Birth Planning and Care of the Neonate Birth of an infant who has a fetoamniotic shunt should occur at a tertiary care center. The presence of a fetoamniotic shunt is not a contraindication to vaginal birth, and careful prenatal evaluation of the maternal/fetal dyad will dictate the
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safest method. In all cases, standard resuscitative equipment should be available at the time of birth, and the team should follow the current neonatal resuscitation procedural guidelines. Women with pregnancies that have undergone in-utero fetal shunting typically give birth at 34 to 35 weeks gestation. Therefore, depending on gestational age at delivery, the neonatal team may need to anticipate some degree of respiratory distress at birth and should have surfactant available. Care of Neonate Requiring a Chest Shunt. If the thoracoamniotic shunt was successful in draining the lesion, the likelihood of neonatal respiratory distress at birth is unusual. Barring any maternal contraindications, a vaginal birth may be appropriate. Birth by ex-utero intrapartum therapy (EXIT) may be necessary in select fetal lung lesion cases based on the degree of mediastinal shift caused by the lesion and the expectation for respiratory compromise at the time of birth. The EXIT procedure is a highly specialized cesarean performed by a multidisciplinary team. During a cesarean birth, an EXIT procedure is performed on the neonate where the umbilical cord is not severed and newborn remains attached to the placenta to provide continuous nutrient exchanges allowing for immediate neonatal surgery. The neonate receives oxygen via the placenta until the chest mass is removed and/or an airway with adequate ventilation is established
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(Howell, Burns, Lenghetti, Kerr, & Harkins, 2002). During thoracoamniotic shunt cases, the resuscitation team should be prepared to place chest tubes for pneumothorax or effusion drainage. When the infant is born, the fetal chest shunt is immediately clamped, carefully removed, and a sterile occlusive dressing is applied at the site to minimize the chance of pneumothorax prior to the infant’s first breath. As shunt displacement is common, providers should anticipate the possibility that the infant may be born without the shunt in place. In such cases, the shunt site is immediately covered with a sterile occlusive dressing. A chest X-ray is obtained as soon as possible to determine the need for a chest tube if oxygenation of the newborn is poor. Newborns are then transported to the neonatal intensive care unit for ongoing monitoring of respiratory status. If the infant is mechanically ventilated, ongoing evaluation of ventilator settings, blood gases and chest X-rays will be required. A pediatric surgeon should be available if emergent resection of the CCAM is necessary.
Care of Infant Requiring Bladder Shunt. Prevention of pulmonary hypoplasia and renal dysplasia are the goals of prenatal treatment of lower urinary tract obstructions. Limited information is available about long-term outcomes of bladder shunting inutero. Prior to birth, the need for ventilation and surfactant therapy should be anticipated due to the history of oligohydramnios or preterm birth. If the bladder shunt is inserted at birth, it should be left in place until a pediatric urologist can evaluate the infant. Depending on the neonate’s disease process, the bladder shunt may continue to facilitate drainage until a Foley catheter or vesicostomy is inserted. Febrile urinary tract infections, reflux, and residual bladder dysfunction may exacerbate preexisting prenatal renal injury (Biard et al., 2005). To evaluate renal injury, long-term renal function measurements and urologic studies such as a voiding cystourethrogram will be necessary to tailor therapy for each individual infant. The total length of neonatal hospitalization is highly variable and is dependent upon a number of factors including the underlying abnormality, the success of the prenatal intervention in treating the abnormality, and the gestational age at delivery. Factors that lengthen the hospital stay may include prematurity, need for ventilatory support, infection, the need for surgical intervention, and delayed feeding.
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Delivery of an infant who has a fetoamniotic shunt should occur in a tertiary care center.
The Nurse’s Role The prenatal diagnosis of a fetal anomaly is associated with increased stress for pregnant women and their families. Pregnancies diagnosed with pleural effusion or CCAM, further complicated by nonimmune hydrops, are at significantly higher risk for fetal and neonatal morbidity and mortality. Perinatal nurses require education about these diagnoses and how best to provide ongoing psychological and emotional support to these special families. The diagnosis of a fetal anomaly destroys the dream of the perfect infant, and women and their families should be supported while they adapt to the reality of the new child. Emotional stress interferes with a woman’s understanding of all the information she receives during the initial counseling. The nurse should be prepared to review information about the diagnosis, prognosis, treatment options, and planned management multiple times with the woman and her family to ensure understanding of the issues involved. Counseling pregnant women undergoing thoraco/vesicoamniotic shunt placement about the fetal and maternal risks and complications of the procedure and obtaining informed consent is important. Research has shown that parents may misunderstand terminology used in antenatal counseling about fetal anomalies, may perceive the counseling they receive as biased, and may receive conflicting or erroneous information from numerous health care providers (Chitty, Barnes, & Berry, 1996). Nurses need to assess the woman’s level of understanding, and as needed solicit further physician involvement in the provision of appropriate information. Some families may also need additional help from a social worker to address and help with financial needs such as housing while they are undergoing procedures or receiving prenatal care. The referring maternal fetal medicine physician may continue surveillance on discharged women. Ongoing communication between providers is important to coordinate care and optimize outcomes. Following the shunt intervention, the woman and family require continuing education related to activity restriction, antibiotic use, signs and symptoms of preterm labor, rupture of membranes and
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other potential complications, and follow-up appointments.
prenatal vesicoamniotic shunting for lower urinary tract obstruction. Obstetrics and Gynecology, 106 (3), 503–508. Callen, P. W. (2007). Ultrasound evaluation of the fetal thorax. In P.W. Callen (ed.). Ultrasonography in obstetrics and gynecology (5th ed., pp. 340, 343). Philadelphia, PA: W.B. Saunders.
Summary
Chitty, L., Barnes, C., & Berry, C. (1996). Continuing with pregnancy
The role of fetal therapy is to optimize outcomes for the fetus with a lower urinary tract obstruction, congenital pleural effusion, or macrocystic CCAM with the utilization of a fetoamniotic shunt. Prenatal screening as well as appropriate counseling that emphasizes the risks and long-term outcomes of successful and unsuccessful shunts procedures is essential. The perinatal nurse is optimally positioned to assess the family’s understanding of their neonate’s diagnosis and the treatment options available. Perinatal nurses play a crucial role in supporting the woman and her family throughout this experience.
after a diagnosis of lethal abnormality: experience of five couples and recommendations for management. British Medical Journal, 313 (7055), 478–480. Fleischer, A., Toy, E., Lee, W., Manning, F., & Romero, R. (eds.) (2011). Maternal fetal surgery and percutaneous ultrasound guided fetal therapy techniques. In Sonography in obstetrics and gynecology: Principles and practice (pp. 803–808). New York, NY: McGraw-Hill Prof Med/Tech. Howell, L. J., Burns, K. M., Lenghetti, E., Kerr, J. C., & Harkins, L. S. (2002). Management of fetal airway obstruction: an innovative strategy. MCN, The American Journal of Maternal Child Nursing, 27 (4), 238–244. Keswani, S. G., Wilson, R. D., & Johnson, M. P. (2006). Percutaneous intrauterine fetal shunting. In J. Apuzzio, A. Vintzileos, and L. Ifty (eds.). Operative Obstetrics ( 3rd ed., pp. 109–120). London, UK: Taylor & Francis Books. Staebler, M., Donner, C., Van Regemorter, N., Duprez, L., De Maertelaer, V., Devreker, F., & Avni, F. (2005). Should determination
REFERENCES
of the karyotype be systematic for all malformations detected
Achiron, R., Weissman, A., Lipitz, S., Mashiach, S., & Goldman,
by obstetrical ultrasound? Prenatal Diagnosis, 25 (7), 567–573.
B. (1995). Fetal pleural effusion: the risk of fetal trisomy. Gynecologic and Obstetric Investigation, 39 (3), 153–156.
holme, T, . . . Adzick, N. (2004). Thoracoamniotic shunts: fetal
doi:10.1159/000292399. Adzick, N., & Kitano, Y. (2003). Fetal surgery for lung lesions, congen-
treatment of pleural effusions and congenital cystic adenoma-
ital diaphragmatic hernia, and sacrococcygeal teratoma. Sem-
toid malformations. Fetal Diagnosis and Therapy, 19, 416–417.
inars in Pediatric Surgery, 12 (3), 154–167. doi:10.1016/s1055-
doi:10.1159/000078994. Wilson, R., & Johnson, M. (2003). Prenatal ultrasound guided percu-
8586(03)00030-1. Bianchi, D. W., Cromblehome, T. M., D’Alton, M. E., & Malone, F. D. (2010). Cystic adenomatoid malformation. In Fetology
(pp.
236–271).
New
York,
NY:
McGraw-Hill.
doi:10.1097/01.AOG.0000171117.38929.eb. Biard, J., Johnson, M., Carr, M., Wilson, R., Hedrick, H., Pavlock, C., & Adzick, N. (2005). Long-term outcomes in children treated by
8
doi:10.1002/pd.1187. Wilson, R., Baxter, J., Johnson, M., King, M., Kasperski, S., Cromble-
JOGNN, 00, 1-8; 2012. DOI: 10.1111/j.1552-6909.2012.01354.x
taneous shunts for obstructive uropathy and thoracic disease. Seminars in Pediatric Surgery, 12 (3), 182–189. Wu, S., & Johnson, M. (2009). Fetal lower urinary tract obstruction. trieved
Clinics
from
in
Perinatology,
36 (2),
377–390.
Re-
http://www.ncbi.nlm.nih.gov/pubmed/19559326
doi:10.1016/jclp.2009.03.010.
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