Toma de decisión compartida en la asesoría preprueba de la ecografía de las 11 a las 13 semanas de gestación: revisión bibliográfica / Shared decision making in pretest counseling at the 11 to 13 weeks ultrasound scan: bibliographic review

Resumen ANTECEDENTES: En el diagnóstico prenatal confluye un grupo de tecnologías enfocadas a la detección de defectos o anomalías congénitas de origen genético y multifactorial. Con independencia del tipo de prueba de que se trate, cualquier tecnología de diagnóstico prenatal debe ir acompañada de asesorías pre y posprueba. La sustentación ética de estas asesorías es de primordial interés para la Medicina prenatal y ha sido tarea de diversas organizaciones. METODOLOGÍA: Estudio retrospectivo, de búsqueda en las bases de datos PubMed, Web of Science y Google Scholar, con los términos MeSH: "Pregnancy", "Prenatal Diagnosis", "Genetic Conuseling", "Relational Autonomy" y "Decision Making". RESULTADOS: Se encontraron 909 referencias de las que se eliminaron las de más de 20 años de publicación, las que no contaban con textos completos y las duplicadas por la búsqueda en distintas bases de datos. Al final se analizaron 25 artículos en texto completo que sirvieron de base para la revisión bibliográfica. CONCLUSIONES: En la actualidad, el ultrasonido es la principal puerta de entrada al mundo del diagnóstico prenatal. Aludir a la indicación y uso éticos de cualquier tecnología de diagnóstico prenatal previene daño al embarazo en su conjunto y desincentiva la necesidad de una normatividad jurídica detallada que, por el momento, no existe en muchos países, incluido el nuestro. Hoy en día se dispone de lineamientos éticos claros para la asesoría de la ecografía como técnica de diagnóstico prenatal.

Abstract BACKGROUND: Prenatal diagnosis brings together a group of technologies that focus on the detection of congenital defects or anomalies of genetic and multifactorial origin. Irrespective of the type of test, any prenatal diagnostic technology must be accompanied by pre- and post-test counselling. The ethical underpinning of such counselling is of paramount interest to prenatal medicine and has been the task of several organisations. METHODOLOGY: Retrospective study, searching PubMed, Web of Science and Google Scholar databases using the MeSH terms: "pregnancy", "prenatal diagnosis", "genetic counselling", "relational autonomy" and "decision making". RESULTS: We found 909 references from which we eliminated those older than 20 years of publication, those without full text and those duplicated by searching in different databases. In the end, 25 full-text articles were analysed and served as the basis for the literature review. CONCLUSIONS: Ultrasound is currently the main gateway to the world of prenatal diagnosis. The ethical indication and use of any prenatal diagnostic technology prevents harm to the pregnancy as a whole and avoids the need for detailed legal regulation, which currently does not exist in many countries, including our own. Clear ethical guidelines are now available for advice on ultrasound as a prenatal diagnostic technique.

Duplicación de imagen ultrasonográfica de feto único intrauterino que emula un gemelo inexistente: reporte de un caso / Ultrasonographic image duplication of an intrauterine unique fetus mimicking non-existing twin: case report

Resumen ANTECEDENTES: En Obstetricia, las imágenes en espejo son artefactos ecográficos infrecuentes que, potencialmente, pueden confundirse con embarazos heterotópicos y propiciar errores diagnósticos e intervenciones iatrógenas. Estas imágenes ficticias se generan por la existencia de una superficie reflectora como, por ejemplo, el intestino distendido o la vejiga repleta. CASO CLÍNICO: Paciente de 39 años, con embarazo por fertilización in vitro, que asiste a evaluación ecográfica del primer trimestre. En la ecografía de rutina a las 11 semanas se observó una imagen en espejo y en la resonancia magnética: útero gestante con una estructura retrouterina hipoecoica, sin feto en el interior. La imagen ecográfica en espejo volvió a reproducirse en el tercer trimestre. El embarazo llegó a término y finalizó por vía abdominal, sin que pudieran demostrarse las estructuras que se advirtieron en la resonancia magnética. CONCLUSIONES: Las imágenes en espejo se han reportado en ultrasonidos de diversas localizaciones pero pocos en la Obstetricia. Todo hizo suponer que la superficie reflectora fue la estructura hipoecoica retrouterina observada, transitoriamente, en la resonancia magnética.

Abstract BACKGROUND: In obstetrics, ultrasonic artifactual mirror images are infrequent, but potentially dangerous since they can be mistakenly interpreted as heterotopic pregnancies, precluding diagnostic errors and iatrogenic interventions. These images require a reflection surface such as dilated bowl or plenty bladder to be generated. OBJECTIVE: We report a first trimester scan ghost twin, diagnosed since first trimester of pregnancy. CLINICAL CASE: 39-year-old patient, with pregnancy due to in vitro fertilization, who attends ultrasound evaluation of the first trimester. Routine ultrasound at 11 weeks showed a mirror image and magnetic resonance imaging: a pregnant uterus with a hypoechoic retrouterine structure, with no fetus inside. The ultrasound mirror image reproduced again in the third trimester. The pregnancy came to an end and ended by abdominal route, without being able to demonstrate the structures that were noticed on the MRI. CONCLUSION: Very few reports of obstetric ultrasound mirror images have been reported. We hypothesize that the transient retrouterine hypoecogenic structure observed by MRI was the reflective surface that create the ghost twin image.

[Intrahepatic cholestasis of pregnancy: review]. / Colestasis intrahepática del embarazo: una revisión.

The etiology of intrahepatic cholestasis of pregnancy includes genetic and environmental factors. Bile acids elevation in maternal and fetal blood is the main fact of its physiopathology, causing maternal itching and high perinatal morbidity and mortality. High levels of maternal blood bile acids are diagnostic. Best treatment is ursodeoxycolic acid and clearly it produces amelioration of bile acid levels and itching, but it is uncertain if it reduces perinatal morbidity and mortality. As far as fetal death is one of sudden onset, probably due to acute hypoxia, tests to evaluate and predict fetal condition are useless. Pregnancy interruption at 36-37 gestation weeks is the best strategy for lowering fetal death incidence. The purpose of this work is to achieve an actualized literature review on this disease.

[Evidence based medicine: diagnosis from a clinical epidemiology point of view. Basic concepts]. / Medicina basada en evidencias: el diagnóstico desde la perspectiva de la epidemiología clínica. Conceptos básicos.

Epidemiology and statistics play an important role in clinical practice. Evidence based medicine is a systematic approach of basic concepts in this areas. It offers a useful framework to enhance the physician ability in clinical research selection and in the same way improves communication between researchers and clinicians. In order to improve patient care in obstetrics and gynecology, this review focuses in general aspects of diagnosis from clinical epidemiology point of view.

[Physical principles, methodology, consistency, and safety in Doppler assessment of the fetal-placental circulation]. / Principios físicos, metodología, consistencia y seguridad del ultrasonido Doppler en la evaluación fetoplacentaria.

Introduction of Doppler ultrasound in obstetrical practice has changed both management and understanding of several diseases that put at risk women and them fetuses. To establish necessary basics and correctly apply this technique, this review will focus in physical principles, acquisition methods, consistency, and safety issues of Doppler ultrasound, in order to improve precision, accuracy and interpretation of this methodology.

[Normal reference values of the pulsatility index and peak systolic velocity in the fetal middle cerebral artery during normal pregnancy]. / Valores de referencia del índice de pulsatilidad y de la velocidad máxima en la arteria cerebral media fetal durante el embarazo normal.

OBJECTIVE: To establish the normal reference values of the fetal middle cerebral artery (MCA) pulsatility index (PI) and MCA peak systolic velocity (PSV) during normal pregnancy. PARTICIPANTS AND METHODS: A total of 727 normally grown fetuses were evaluated with pulsed Doppler ultrasound between 20 and 40 weeks of gestation. The MCA was located in a transverse view of the fetal head 1 cm after its origin from the Willis vascular circle. The insonation angle was always kept as close as possible to 0. The PI and PSV were measured in 5 consecutive and uniform cardiac cycles and the mean considered as the representative for each case. Normal reference values for each gestational week were constructed. Reproducibility and agreement were analyzed for the MCA PI estimation. RESULTS: There was a significant correlation between MCA PSV and gestational age (GA) (PSV = -13.81+1.96 X GA, r2 = 0.59, p=0.001). The correlation between MCA PI and GA showed an initial increment until week 30 with a further reduction towards the end of the pregnancy (MCA PI = 2.44 + -0.02 X EG, r2 = 0.09). Reproducibility analysis of the MCA PI estimation showed an intra-class and inter-class correlation coefficients of 0.89 (95%CI 0.65-0.97) and 0.87 (95% CI 0.63-0.93), respectively. Agreement evaluation showed a mean difference between observers of 0.03 (standard deviation 0.19), with 95% limits of agreement of -0.41 a 0.35. CONCLUSION: The normal reference values obtained in this study confirm the diagnostic and prognostic capacity of the fetal MCA PI and the MCA PSV evaluation in high risk pregnancies.

[Normal reference values of the pulsatility index from the uterine and umbilical arteries during pregnancy]. / Valores de referencia del índice de pulsatilidad de las arterias uterina y umbilical durante el embarazo.

OBJECTIVE: To establish the normal reference values of the pulsatility index in the uterine (UtA PI) and umbilical (UmA PI) arteries during pregnancy. PATIENTS AND METHODS: A total of 2081 normal pregnancies with normal growth fetuses were evaluated with pulsed Doppler ultrasound (US) between 20 and 40 weeks of gestation (WG). Both, UtA and UmA, were located with color Doppler US and PI measured in 5 consecutive and uniform cardiac cycles. In the uterine arteries, mean PI from the left and right arteries (Mean UtAPI) was calculated and the prevalence of unilateral or bilateral "notch" documented. Normal reference values for each gestational week were constructed, and reproducibility analyzed. RESULTS: There was a negative correlation between the gestational age and PI values from both arteries (Mean UtAPI = 1.57 + -0.02 X WG, r2= 0.07; PI UmA = 1.56 + -0.02 X WG, r2= 0.15). The prevalence of unilateral and bilateral "notch" in the uterine arteries was (median) 5% (range 3-10%), and 17% (range 4-23%), respectively. Reproducibility analysis for calculation of the Mean UtAPI showed an intraclass and interclass correlation coefficients of 0.87 (95% confidence intervals [CI] 0.74 - 0.93) and 0.78 (95% CI 0.59-0.88), respectively, and for UmAPI, 0.97 (95% CI 0.93-0.98) and 0.94 (95% Cl 0.88-0.97), respectively. Agreement analysis between observers for the calculation of the Mean UtAPI showed a mean difference of 0.01 (SD, 0.13) (95% limits of agreement [95% LA] -0.27-0.28) and for the UmAPI mean difference of 0.04 (SD 0.16) (95% LA, -0.29 - 0.36). CONCLUSION: The reference values here obtained of the mean UtA PI and UmAPI can be applied in the clinical surveillance of normal and complicated pregnancies.

[Differences and similarities of preeclampsia and gestational hypertension]. / Diferencias y similitudes de la preeclampsia y la hipertensión gestacional.

Current criteria regarding hypertension in pregnancy consider two distinct types: gestational hypertension (pure type) and preeclampsia-eclampsia syndrome, the latter with albuminuria as a mandatory clinical fact. However, reports of lasts years show that a 15 to 46% of cases classified as pure type gestational hypertension evolve to a preeclamptic state, underlying the possibility that both clinical conditions represent diferent stages of the same disease. On the other hand, albuminuria may not be present in severe cases of pregnancy-related hypertensive disorders such as HELLP syndrome or eclampsia. It follows that if albuminuria is not necessary to establish the most severe forms of the disease, must the non-albuminuric hypertensive-type still be considered as a diferent diagnosis? This report reviews the medical literature on the subject, stressing similarities and diferences of both conditions in order to reflect about the need to change the classification concepts pregnancy-related hypertensive entities.

Colestasis intrahepática del embarazo, un riesgo fetal impredecible: presentación de un caso y revisión de la literatura / Intrahepatic Cholestasis of pregnancy, an umpredictable fetal risk: a case report and liteature review

Se presenta un caso de colestasis intrahepática del embarazo (CIE) que tuvo muerte fetal unas horas después de un registro cardiotocográfico normal. Es una mujer de 35 años con el antecedente de dos embarazos que cursaron con dicha enfermedad y tuvieron un buen desenlace. En el último embarazo tuvo nuevamente un cuadro clínico y bioquímico característicos de CIE. La evolución cardiotocográfica y ecográfica del embarazo fueron normales, salvo por tratarse de un feto pequeño para la edad de crecimiento armónico. A las 35 4/7 semanas inició actividad uterina prodrómica y una prueba de registro basal fue reactiva. Ocho horas después la paciente regresó para revalorar su hospitalización y se demostró la existencia de un óbito fetal. El estudio genético del producto y la valoración histológica de la placenta, fueron normales. La colestasis materna revirtió unas semanas después del parto.