Asunto(s)

RESUMEN

This chapter describes several circumstances in which the interpretation of the intrapartum fetal heart rate pattern falls outside the usual frame of reference. This includes a more extensive discussion of causes of tachycardia and bradycardia. Ways in which a fetal dysrhythmia may manifest itself in the context of heart rate monitoring are described. Finally, the chapter reviews technological innovations designed to clarify the fetal status when compromise is suspected from the fetal heart rate pattern.

Asunto(s)

RESUMEN

Preeclampsia is one of the most serious pregnancy - specific medical conditions of increasing incidence. It remains a major cause of maternal and fetal morbidity and mortality. Although maternal mortality is especially high in developing countries, preeclampsia and its complications are one of the top four causes of maternal deaths even in developed societies. Unfortunately, yet the only effective and definitive treatment of preeclampsia is delivery of the baby and placenta, and its time depends on the disease severity and gestational age. In this review, we report principles of management of preeclampsia in the light of current international recommendations. Suggested failure of the placental development and significant role of angiogenic factors and their receptors in etiology of preeclampsia give the possibility for their future use in diagnosis and risk assessment of the disease and open new chapter of possible solutions also in the field of treatment of this serious pregnancy complication. Introduction of an advanced form of therapy that could safely prolong the duration of pregnancy would be invaluable in the area of preeclampsia management and lowering perinatal complications, especially in women with early-onset severe preeclampsia.

Asunto(s)

RESUMEN

OBJECTIVE: Electronic fetal monitoring (EFM) correlates poorly with neonatal outcome. We present a new metric: the "Fetal Reserve Index" (FRI), formally incorporating EFM with maternal, obstetrical, fetal risk factors, and excessive uterine activity for assessment of risk for cerebral palsy (CP). METHODS: We performed a retrospective, case-control series of 50 term CP cases with apparent intrapartum neurological injury and 200 controls. All were deemed neurologically normal on admission. We compared the FRI against ACOG Category (I-III) system and long-term outcome parameters against ACOG monograph (NEACP) requirements for labor-induced fetal neurological injury. RESULTS: Abnormal FRI's identified 100% of CP cases and did so hours before injury. ACOG Category III identified only 44% and much later. Retrospective ACOG monograph criteria were found in at most 30% of intrapartum-acquired CP patients; only 27% had umbilical or neonatal pH <7.0. CONCLUSIONS: In this initial, retrospective trial, an abnormal FRI identified all cases of labor-related neurological injury more reliably and earlier than Category III, which may allow fetal therapy by intrauterine resuscitation. The combination of traditional EFM with maternal, obstetrical, and fetal risk factors creating the FRI performed much better as a screening test than EFM alone. Our quantified screening system needs further evaluation in prospective trials.

Asunto(s)

RESUMEN

Electronic fetal monitoring (EFM) has aided intrapartum fetal surveillance for more than four decades. In spite of numerous trials comparing EFM with standard fetal heart rate (FHR) auscultation, it remains unclear that this modality has led to improved perinatal outcomes, especially lower rates of perinatal morbidity and mortality. A variety of ancillary methods have been developed to improve the accuracy of EFM for predicting fetal compromise. At present, a limited number of studies have shown that the addition of fetal electrocardiogram (ECG) analysis to visual interpretation of FHR patterns resulted in better fetal outcomes. However, the shortcomings of visual interpretation of FHR patterns persist. Although automated systems for FHR analysis have been developed, they have not been widely used or proven to enhance the value of intrapartum fetal surveillance. This article discusses future directions for novel intrapartum fetal surveillance systems that leverage the long experience gained from EFM to enhance the level of risk assessment and prognosis.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

OBJECTIVE: To examine trends in electronic fetal monitoring (EFM) use and quantify the extent to which such trends are associated with changes in rates of primary cesarean delivery and neonatal morbidity and mortality. METHODS: We carried out a retrospective study of more than 55 million nonanomalous singleton live births (24-44 weeks of gestation) delivered in the United States between 1990 and 2004. Changes in the risks of neonatal mortality, cesarean delivery, and operative vaginal delivery for fetal distress, 5-minute Apgar score lower than 4, and neonatal seizures (at 34 weeks of gestation or after) were examined in relation to changes in EFM use. RESULTS: Electronic fetal monitoring use increased from 73.4% in 1990 to 85.7% in 2004, a relative increase of 17% (95% confidence interval 16-18%). This increase was associated with an additional 5% and 2% decline in early and late neonatal deaths, respectively, at 24-33 weeks of gestation as well as a 4-7% additional decline in the 5-minute Apgar score lower than 4 at 24-33, 34-36, and 37-44 weeks of gestation. Increasing EFM use was associated with a 2-4% incremental increased rate of both cesarean delivery and operative vaginal delivery for fetal distress at 24-33, 34-36, and 37-44 weeks of gestation. Increasing EFM was not associated with any temporal changes in the rate of neonatal seizures. CONCLUSIONS: The temporal increase in EFM use in the United States appears to be modestly associated with the recent declines in neonatal mortality, especially at preterm gestations. LEVEL OF EVIDENCE: II.

Asunto(s)

RESUMEN

La vasa previa es una situación que se produce cuando vasos fetales intramembranosos aberrantes, procedentes de la placenta o del cordón umbilical, atraviesan el orificio cervical interno y se sitúan por delante de la presentación fetal. Su incidencia es de 1/2.000-1/3.000 embarazos, y la mortalidad perinatal asociada es del 52-66%, aproximadamente. La reducción de esta elevada mortalidad se basa en su diagnóstico prenatal. Exponemos a continuación el caso clínico de una gestante, con controles obstétricos correctos, que acude a urgencias a las 34,5 semanas por rotura prematura de membranas, objetivándose un líquido amniótico hemático y bradicardia fetal severa, por lo que se realiza una cesárea urgente, naciendo una niña con anemia severa, que ingresa en la unidad de neonatología, presentando buena evolución posterior. Presentamos también una revisión de la literatura de los años 1980 al 2008, a través de Medline, usando las palabras «vasa previa» (AU)

Vasa previa is a condition in which the intramembranous fetal blood vessels within the placenta or umbilical cord cross the internal os and become trapped between the fetus and the opening of the birth canal. The incidence of this entity varies from 1/2000 to 1/3000 pregnancies and the associated perinatal mortality rate has been reported to be as high as 52-66%. Reduction of this high perinatal mortality depends on prenatal diagnosis. We report the case of a pregnant woman with no abnormalities in antenatal visits who presented to the emergency service at 34.5 weeks of pregnancy due to premature rupture of membranes, at which time blood-stained amniotic fluid and severe fetal bradycardia were noted. An emergency cesarean section was performed. A female neonate was delivered with severe anemia. The neonate was admitted into the neonatology unit and subsequent outcome was favorable. We also provide a review of the literature published between 1980 and 2008 using Medline, with the key words "vasa previa" (AU)

Asunto(s)

RESUMEN

Electronic fetal monitoring (EFM) using cardiotocography is a common tool used during labor and delivery for assessment of fetal well-being. It has largely replaced the use of intermittent auscultation and fetal scalp pH sampling. However, data suggesting improved clinical outcomes with the use of EFM are sparse. In this review, the history of EFM is revisited from its inception in the 1960s to current practice, interpretations, and future research goals.

Asunto(s)

RESUMEN

We performed a follow-up national survey concerning intrapartum fetal surveillance in Sweden to investigate if routines had changed since a previous survey in 1999, due to new data that have emerged since and technical developments. All labor wards throughout Sweden, with sizes varying from around 350 to more than 9,000 deliveries per year, have at present a rather uniform policy for intrapartum fetal surveillance with electronic fetal monitoring (EFM). They all use admission tests, fetal scalp blood sampling and have written guidelines for EFM. However, only 72% have written guidelines for fetal blood sampling. In 89% of the units lactate is analyzed in the fetal blood sampling. In half of the units the STAN-monitor is used.

Asunto(s)

RESUMEN

The technology of intrapartum surveillance made rapid strides from the 1960s through the 1980s but then stagnated as increasing resort to caesarean section was made rather than improving measures of fetal condition and labour progress. However, despite caesarean section rates commonly over 30%, medicolegally expensive mistakes continue to be made because it is difficult to teach clinicians to make reliable use of existing technology. It may be that as with aircraft navigation, the safest solution is to replace human judgement with the obstetric equivalent of automatic pilots.

Asunto(s)

RESUMEN

For three decades, cardiotocography has been the basic technique for fetal surveillance during labor, but its impact on fetal well-being remains controversial. The benefits and disadvantages of fetal monitoring with cardiotocography during labor are reviewed. Special reference is made to the possible effect on the rate of neonatal seizures in newborns and their long-term outcome.

Asunto(s)

RESUMEN

Se buscó valorar la utilidad de la pulsioximetría fetal intraparto para diferenciar los patrones de frecuencia cardíaca fetal definidos según una clasificación funcional. Se incluyeron 534 gestantes, monitorizadas durante el período de dilatación con registro cardiotocográfico y pulsioximetría fetal. Los registros de frecuencia cardíaca fueron clasificados de acuerdo con un modelo basado en la respuesta clínica. Las cifras de FSpO2 en los fetos con trazados normales de frecuencia cardíaca son mayores que en los restantes 4 grupos (p < 0,05). El conjunto con registros compatibles con acidosis muestra valores 0 menores que los grupos con patrones normales, de estrés y atípico s (p < 0,05). No se evidencian diferencias significativas en el resto de los grupos. En cuanto al grado de oxigenación fetal, la clasificación funcional sólo muestra utilidad en situaciones en que los trazados de frecuencia cardíaca resultan claramente definidos, resultando escasamente útil cuando los trazados no corresponden a patrones normales o a aquellos claramente patológicos (AU)

Foetal pulse oximetry can distinguish between normal patterns of cardiotocographic findings and patterns compatible with foetal acidosis, but are not useful in identifying patterns that indicate atypical changes or stress. Objective: To evaluate the usefulness of intrapartum foetal pulse oximetry in distinguishing between foetal heart rate patterns defined according to functional criteria. Subjects and methods: A total of 534 pregnant women were monitored with cardiotocography and foetal pulse oximetry during dilation. Heart rate tracings were classified according to a model based on clinical response. Results: FSpO2 values in foetuses with normal heart rate tracings were higher than in the other 4 groups (p<0.05). Tracings compatible with acidosis were associated with lower oxygen levels than normal tracings, atypical tracings and tracings indicative of stress (p<0.05). There were no significant differences between the other groups. Conclusions: Use of foetal oxygenation findings to reach a prognosis regarding functional classification was useful only when interpretation of the heart rate tracings was straightforward, and was of limited use when the tracings did not clearly reflect either a normal or clearly pathological status (AU)

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Auscultation or recording of foetal heart tones is possible throughout pregnancy. In the first trimester, the presence of heart activity proves a vital pregnancy and reduces the probability of spontaneous abortion. From the end of the second and during the whole of the third trimester foetal heart activity can be used to asses the foetal condition. The introduction of cardiotocography failed to reduce serious perinatal morbidity or mortality as compared with intermittent auscultation, but did increase the number of obstetrical interventions.

Asunto(s)

RESUMEN

Modern intensive monitoring of the fetus during labor affords the opportunity for the greatest possible safety to the infant, whilst at the same time dispensing with unnecessary operations to terminate labor which can be dangerous for the mother and her child. Developments over the past 28 years, since cardiotocography has been in clinical use, have unfortunately also been accompanied by confusion and mistakes. We think that there are two main reasons for this: I. Many who use cardiotocography have not assessed its efficiency correctly. Heart rate pattern with all their variations have too often been regarded as the only diagnostic criteria for the determination of fetal hypoxia. However this procedure only allows a rough selection of actually endangered fetuses. In more than 50% of the cases with a suspicious or pathologic cardiotocogram there is no concrete clinical evidence of manifest danger of hypoxia. II. Investigations concerning the practical importance of monitoring the fetus during labor were often not based on actual clinical indications. Attempts were made to prove that continuous electronic monitoring of the fetal heart rate could be replaced by simple traditional auscultation. Furthermore due to failure to appreciate the real efficiency of cardiotocography, this truly excellent method was in fact blamed for the faults arising from wrong interpretation, instead of underlining the lack of logic of the investigators concerned. After all, several prospective studies, that have examined the efficiency of various monitoring strategies, demonstrate the shortcomings of these techniques in the clinical setting and have shown them to have no relevance in every practice. Presently the most suitable way to monitor the fetus during labor is to combine cardiotocography with a biochemical method. At the moment fetal blood analysis is the most suitable test to be performed in cases where the cardiotocogram is not normal. Then the role of fetal blood analysis is to find out whether in fact a danger of hypoxia is threatened or not. Today the most urgent task when monitoring the fetus during labor is not so much to reduce the number of cases of cerebral palsy since these are seldom caused by intrapartum asphyxia. The major objective is now recognised to be to prevent early morbidity of the fetus, newborn, and the consequences that flow from this. The excellent results of combined intensive monitoring of the fetus during labor are particularly well illustrated by the intrapartum mortality in our hospital during different periods when monitoring practice has been progressively and methodically improved by stages. During the period when monitoring consisted of simple auscultation used on its own, the intrapartum mortality was 0.56%. After the introduction of fetal blood analysis--at that time cardiotocography did not yet exist--the mortality sank to 0.32%. During the first ten years of cardiotocography combined with fetal blood analysis the mortality reduced further to 0.17%, and during the following 13 years it reached to a minimal level of 0.4%. Finally, in this review, other aspects are commented on such as oximetry. Oximetry, presently used as pulse oximetry, as an additional biochemical method will possibly be incorporated as the third method of monitoring the fetus during labor. Oximetry could also be used as an automatic alarm system in the labor ward when fetal O2 levels drop below a particular limit to draw the attention of the staff to the case concerned. Up to now this has not been convincingly achieved with the use of cardiotocography.

Asunto(s)

Asunto(s)

RESUMEN

En 1989 en el Hospital Civil de Guadalajara realizamos un estudio con 100 pacientes con embarazo a término, inicio de trabajo de parto y feto vivo. A todas las mujeres se les realizó interrogatorios sobre la intensidad subjetiva de los movimientos fetales, se les practicó aqmnioscopia y registro carditocográfico comparandose los resultados obtenidos con el Apgar de los recién nacidos al minuto y 5 minutos. Los movimientos fetales fueron normales en 91 por ciento de los cuales 95.7 por ciento tuvieron Apgar * al minuto y 98.9 por ciento Apgar * 8 a los 5 minutos; líquido amiótico claro en 75 por ciento de los cuales 94.6 por ciento tuvieron Apgar * 7 al minuto y 100 por ciento Apgar * 8 a los 5 minutos y 94 por ciento con cardiotocografía normal de los cuales 95.7 por ciento tuvieron Apgar * 7 al minuto y 100 por ciento Apgar * 8 a los 5 minutos. En la predicción de fetos con sufrimiento fetal el manejo método fue la cardiotocografía y el menos útil fue la presencia de líquido amniótico meconial. Se concluye que la predicción del bienestar fetal es similar con la evaluación de la intensidad de los movimientos fetales que con la amnioscopia y cardiotocografía y que es un método que debería utilizarse en todos los servicios de atención obstétrica.

Asunto(s)