HYDROPS FETALIS MEDICAL CARE
Category: Child Health
Abstract : hydrops fetalis medical care : The single most important factor to ensure proper treatment of the fetus with hydrops is a precise and detailed diagnosis. Until the underlying pathophysiology is clearly understood and the extent of the abnormalities leading the development of hydrops is defined completely, any attempt at treatment is futile and potentially harmful. • Once the under
hydrops fetalis medical care : The single most important factor to ensure proper treatment of the fetus with hydrops is a precise and detailed diagnosis. Until the underlying pathophysiology is clearly understood and the extent of the abnormalities leading the development of hydrops is defined completely, any attempt at treatment is futile and potentially harmful.
• Once the underlying problems are understood completely, address the question of whether the abnormalities present are compatible with life, whether fetal survival would be at the cost of an unacceptably poor quality of life, and what the consequences may be for future generations. Currently, parental involvement and guidance are fundamental requirements and require full knowledge by the parents of all possible potential consequences.
• If the decision is made to continue the pregnancy, the next steps are to decide whether to intervene with invasive fetal treatment(s) and to determine at what point preterm delivery represents less risk for the fetus than continued gestation. Because major uncertainties about these questions inevitably exist, regardless of the underlying cause(s), full parental involvement is essential.
• Decisions about fetal treatment are inevitably uncertain because the necessary evidence is not available. While many anecdotal approaches are found in the literature, no properly designed clinical trials are available for the clinician concerned with evidence-based management.
o Many treatment schemes exist; however, all are based on the biases and experiences of the individual author(s). In such circumstances, treatment decisions are difficult, particularly for the prudent clinician who requires evidence to balance risks against benefits of a specific treatment.
o To further complicate the issue, spontaneous remission of the hydropic process has been reported in hundreds of cases. Underlying causes in these cases include cardiac arrhythmias, twin-to-twin transfusion syndrome, pulmonary sequestration, cystic adenomatoid malformation of the lung, lysosomal storage diseases, cystic hygroma with or without Noonan syndrome, both Parvovirus and CMV infections, placental chorangioma, and idiopathic ascites or pleural effusions. Both clinician(s) and parent(s) completely must understand that decisions at this point basically are uncertain and arbitrary.
• Unproven high-risk treatments are easier to accept when they consist of procedures targeted to correct the underlying pathophysiology leading to fetal hydrops. Thus, the most widely accepted management schemes include fetal transfusion to correct anemia (regardless of cause), drug treatments for cardiac arrhythmias, correction or reduction of space-occupying lesions that impede cardiac venous or lymphatic return, and procedures designed to stop fetal loss of blood, regardless of cause.
• Treatment reported for fetal arrhythmias has included doing nothing, administering drugs, and immediate delivery.
o If fetal maturity permits, the most simple and direct approach is obviously delivery of the affected fetus and direct neonatal treatment of the arrhythmia.
o When fetal immaturity prevents this approach, use of drugs has generally been accepted as appropriate. However, whether this is justified is not supported by any evidence from controlled clinical trials, and the frequency with which spontaneous cessation of the arrhythmia and remission of the hydrops has been reported should promote more skepticism and caution about fetal drug treatment than generally has been standard.
o Drugs have been administered to the mother (oral, intramuscular, intravenous), to the fetus (intraperitoneal, intramuscular, intravenous via cordocentesis), and to both, attempting to correct fetal arrhythmias.
o Even fetal pacing has been reported. As perhaps expected, the failures are infrequently reported while the successes serve as topics for case or case-series reports (ie, reporting bias). Such treatment is not without risk, partly consequent to the drugs used and not uncommonly related to the mode of administration.
o Drugs used have included digitalis, furosemide, flecainide, verapamil, amiodarone, propanolol, procainamide, quinidine, adenosine, sotalol, terbutaline, corticosteroids, and immunoglobulins; a variety of combinations of these drugs have also been used. While adenosine appears to be particularly effective with supraventricular arrhythmias, and corticosteroid therapy seems effective for complete fetal heart block associated with maternal collagen diseases, choice of drug remains empiric and arbitrary, until such time as definitive evidence from clinical trials becomes available.
o The prudent physician may choose the approach that offers the least risk to fetus and mother until more definitive data are available.
• The success of intrauterine intraperitoneal fetal transfusion with packed RBCs in the treatment of the severely anemic fetus of the isoimmunized pregnancy has been a modern success story for perinatal medicine. Unfortunately, historic controls form the basis for this conclusion, and definitive evidence from clinical trials will probably never be available.
o Use of this procedure to correct fetal anemia from a variety of other causes (eg, hemorrhage into a twin, from highly vascularized tumor masses, consequent to marrow aplasia with severe fetal infection, hemoglobinopathy) has been reported with many favorable outcomes. Again, whether this is real or a consequence of reporting bias is uncertain.
o Nevertheless, fetal transfusion using the intraperitoneal route has apparently become accepted as the standard of care for the fetus with severe anemia.
• However, more recently a more direct approach has been used with increasing frequency.
o Reported routes of fetal administration of blood products have included percutaneous umbilical vein, intrahepatic umbilical vein, umbilical artery, and a variety of combined approaches. Even intracardiac transfusions have been reported. Success has been claimed with fetal partial packed-cell exchange transfusion, maternal plasmapheresis, maternal promethazine or corticosteroid treatment, fetal intravenous Ig-G, fetal platelet transfusion, and fetal administration of human granulocyte-stimulating factor, again using a variety of routes.
o Use of more direct invasive methods may appear to increase fetal risk. This may not appear justified in view of the very low risks demonstrated to accompany the intraperitoneal route. The prudent clinician may be justified in taking a very cautious approach to these newer therapeutic techniques until such time as definitive evidence is available that the benefit-to-risk ratio of them is better.
• Severe hemorrhage from friable, highly vascular tumor masses and acute, massive hemorrhage from one twin to another often result in quick fetal death. While those who survive may appear to benefit from fetal transfusion, as described above, continued hemorrhage may make such efforts futile. Thus, a more aggressive approach in such conditions may be justified.
o For example, surprising success has been reported with tumor debulking surgery for the fetus with sacrococcygeal tumor and with surgical removal of actively bleeding, highly vascularized fetal intraabdominal, thoracic, or placental masses.
o Photocoagulation and radiofrequency thermal ablation techniques also demonstrate much promise in this regard. The information is preliminary; most of it comes from animal studies, and no extensive clinical trial experience in the human fetus is currently available. Nevertheless, life-threatening disease may justify life-threatening treatment in some cases, and use of such technology in situations of active fetal hemorrhage may hold considerable promise. Use of these techniques to correct massive arteriovenous shunting causing fetal hydrops also demonstrates real promise of effectiveness.
• The twin-to-twin transfusion syndrome presents a somewhat more puzzling problem. The temptation to transfuse the anemic fetus is apparent in the literature; however, no evidence of overall benefit from this approach exists.
o As noted earlier, if 1 twin has developed hydrops in this situation, it is most often the recipient twin, not the donor. Thus, volume reduction in the recipient or combined transfusion/reduction procedures to the twins appears to be more logical but has seldom been used.
o Feticide of the affected twin has often been reported; however, subsequent development of hydrops in the previously normal twin is surprisingly commonly reported. Thus, the management of the twin-to-twin transfusion syndrome is currently an unresolved problem.
• Space-occupying masses, which impair venous or lymphatic return, are among the more important causes of fetal hydrops. Management varies depending on the type of lesion and from center to center. However, the fundamental basis for most treatments has been reduction or removal of the mass when immediate delivery is not practical.
o Pleural effusions have been managed with single or serial fetal thoracenteses, pleurothoraco-amniotic shunts, and direct fetal surgical maneuvers to correct the underlying cause(s).
o Pericardial effusions have been managed similarly with single or serial pericardiocenteses or continuous drainage maneuvers.
o Ascites has also been treated with single or multiple taps, peritoneo-amniotic shunts, and intraperitoneal albumin. Successes and failures have been reported with all methods; no evidence exists that 1 approach is any better than another because proper comparative trial data do not exist in the literature.
o Fetal surgery with definitive correction of the underlying anomaly has been reported with increasing frequency. Improved fetal survival with cystic adenomatoid malformation and with bronchopulmonary sequestration has been observed in several large series in which these direct corrective measures have been employed. While this success has been measured against outcomes using historic controls, such measures make physiologic sense and, thus, demonstrate considerable promise.
• Resuscitation and delivery room management of hydrops fetalis pose a unique set of problems for the neonatologist.
o Once hydrops has been diagnosed antenatally, make every effort to establish the cause; this is helpful in treating the infant at birth.
o In addition to appropriate equipment and supplies, a skilled team of experienced health care professionals (neonatologists, nurses, respiratory therapists, radiograph technician, ultrasound technician) should be present in the delivery room.
o Perform or repeat antenatal ultrasound examination to assess the presence and extent of pleural effusion, pericardial effusion, or ascites prior to delivery because the fluid may require aspiration in the delivery room to establish adequate ventilation and circulation.
o Fetal blood assessment by percutaneous umbilical sampling, although risky, may be helpful in selected cases for early management. o After establishing the infant's airway and ventilation, place umbilical arterial and venous catheters to monitor arterial pressure, blood gases, and venous pressure.
o Packed erythrocytes or whole blood crossmatched with the mother's blood should be available for partial exchange transfusion to correct severe anemia, even when due to nonimmune causes.
o Anticipate and promptly correct metabolic derangements such as acidosis and hypoglycemia.
o Surfactant deficiency and hypoplastic lungs may be associated with hydrops and are managed accordingly.
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