The benefit of active management in true knot of the umbilical cord: a retrospective study.

PURPOSE: To compare perinatal outcomes between active and routine management in true knot of the umbilical cord (TKUC). METHODS: A retrospective study of singletons born beyond 22 6/7 weeks with TKUC. Active management included weekly fetal heart rate monitoring(FHRM) ≥ 30 weeks and labor induction at 36-37 weeks. Outcomes in active and routine management were compared, including composite asphyxia-related adverse outcome, fetal death, labor induction, Cesarean section (CS) or Instrumental delivery due to non-reassuring fetal heart rate (NRFHR), Apgar5 score < 7, cord Ph < 7, neonatal intensive care unit (NICU) admission and more. RESULTS: The Active (n = 59) and Routine (n = 1091) Management groups demonstrated similar rates of composite asphyxia-related adverse outcome (16.9% vs 16.8%, p = 0.97). Active Management resulted in higher rates of labor induction < 37 weeks (22% vs 1.7%, p < 0.001), CS (37.3% vs 19.2%, p = 0.003) and NICU admissions (13.6% vs 3%, p < 0.001). Fetal death occurred exclusively in the Routine Management group (1.8% vs 0%, p = 0.6). CONCLUSION: Compared with routine management, weekly FHRM and labor induction between 36 and 37 weeks in TKUC do not appear to reduce neonatal asphyxia. In its current form, active management is associated with higher rates of CS, induced prematurity and NICU admissions. Labor induction before 37 weeks should be avoided.

Double and Single True Knot of an Umbilical Cord: A Case Report.

The primary function of the umbilical cord is to transport blood to and from the fetus. It carries deoxygenated blood away from the fetus by two umbilical arteries, and oxygenated blood from the placenta toward the fetus by an umbilical vein. In some cases, the umbilical cord can form a true knot increasing the risk of asphyxia and fetal demise. The umbilical cord may also form a false knot, which is only a kink and will not increase fetal risk of abnormalities. A 40-year-old woman, gravida six, parity three (G6P3), presented to the hospital in active labor after 39.1 weeks of gestation. Six hours after admission a healthy male fetus was delivered with one nuchal cord. The placenta was delivered approximately 3 minutes later. Upon inspection, the presence of a double and a single true knot of the umbilical cord was noted. This case describes a fetus with a double and single true knot of the umbilical cord that was not apparent by ultrasonography.

True Knot of the Umbilical Cord and Associated Adverse Perinatal Outcomes: A Case Series.

An actual knot that forms during pregnancy is known as a true knot of the umbilical cord (TKUC) which is seen in 0.3% to 1.2% of pregnancies. TKUC is noteworthy because it can lead to a variety of adverse perinatal outcomes, including infants with low Apgar scores, small for gestational age (SGA) fetuses, fetal hypoxia, and also in some cases fetal death. Here, we present instances of TKUC of three patients and the various associated perinatal outcomes.

Nudo verdadero como causa de taquicardia fetal persistente Reporte de un caso / True Knot as a Cause of Persistent Fetal Tachycardia. Case Report

Resumen Las anomalías del cordón umbilical están asociadas a efectos adversos durante el embarazo. El nudo verdadero del cordón umbilical está presente en el 0.3-2.1% de los embarazos y se ha asociado a muerte fetal. Dentro de los factores de riesgo se incluye, la edad materna, índice de masa corporal (IMC) elevado, multiparidad, trastornos hipertensivos, tabaquismo, polihidramnios, diabetes gestacional, sexo masculino del feto y otras malformaciones. El diagnóstico prenatal del nudo verdadero es raro y un desafío. La mayoría se diagnostica durante el nacimiento y sólo el 0.08% de los nudos verdaderos son diagnosticados de manera prenatal. El registro cardiotocográfico puede registrar trazos no tranquilizadores que reflejan que hay un estrés hipóxico o mecánico que interrumpe la oxigenación fetal. El objetivo de este reporte es mostrar un caso de nudo verdadero del cordón umbilical que presentó taquicardia fetal persistente durante el trabajo de parto con terminación del embarazo vía vaginal.

Abstract Umbilical cord abnormalities are associated with adverse effects during pregnancy. The true umbilical cord knot is present in 0.3-2.1% of pregnancies and has been associated with fetal death. Risk factors include maternal age, high BMI, multiparity, hypertensive disorders, smoking, polyhydramnios, gestational diabetes, male sex of the fetus, and other malformations. Prenatal diagnosis of the true knot is rare and challenging. Most are diagnosed at birth and only 0.08% of true knots are diagnosed prenatally. Non-reassuring cardiotocography traces may be present, reflecting hypoxic or mechanical stress disrupting fetal oxygenation. The aim of this case report is to present a case of true umbilical cord knot presenting with persistent fetal tachycardia during labor, resolved by vaginal delivery.

Adverse Perinatal Outcomes of True Knot of the Umbilical Cord: A Case Series and Review of Literature.

A true knot of the umbilical cord (TKUC) is an actual knot formed in pregnancy. It is seen in approximately 0.3%-1.2% of all pregnancies. True knots are of significance as they can cause a wide spectrum of adverse perinatal outcomes like small for gestational age (SGA) fetus, low appearance, pulse, grimace, activity, and respiration (Apgar) score at birth, fetal hypoxia, and even fetal demise. Here, we report a case series of three patients with TKUC and the varied adverse perinatal outcomes associated with them. A low-risk primigravida at term gestation had a suspicious non-stress test (NST). Repeat NST after maternal resuscitation became pathological. Emergency cesarean delivery was performed in view of pathological NST persisting despite intrauterine resuscitation. A healthy male baby weighing 2920 g was delivered, and the umbilical cord had a true knot. A multigravida at 33 + 3 weeks of gestation was referred with fetal growth restriction (FGR). Color Doppler examination showed absent end-diastolic flow (AEDF) in the umbilical artery (UA). Cesarean delivery was performed in view of FGR stage two with AEDF in the UA at 34 weeks of gestation as per the Barcelona criteria. A male baby weighing 1505 g was delivered. The umbilical cord had a true tight knot. The baby had an Apgar score of 7 at one minute after birth but was shifted to the neonatal intensive care unit (NICU) in view of low birth weight and prematurity. The baby slowly gained weight and was discharged from NICU after 15 days in stable condition. A multigravida at 32 weeks of gestation was referred with intrauterine fetal demise. Ultrasonography confirmed the presence of a single intrauterine dead fetus corresponding to 30 + 4 weeks of gestation with an estimated fetal weight (EFW) of 1633 g, amniotic fluid index (AFI) equal to nine, and presence of Spalding's sign. Induction of labor was done, and she expelled a dead macerated male fetus weighing 1825 g. The infantogram was normal. A true umbilical cord knot was found. The umbilical cord is the source of fetal blood supply; therefore, any cord abnormality can have a significant impact on the fetal outcome. There are various factors that can predispose to TKUC, such as polyhydramnios, increased cord length, monoamniotic twins, male baby, grand multiparity, small fetus, and amniocentesis. TKUC can lead to various adverse outcomes in pregnancy and labor like SGA fetus, low Apgar score at birth, fetal hypoxia, and fetal demise. TKUC increases the risk of fetal demise by as much as four times. With the development of advanced techniques such as three-dimensional/four-dimensional color Doppler ultrasounds, TKUC can be diagnosed antenatally in the form of a four-leaf-clover, a "hanging-noose sign," or by an unusual multicolor pattern in the cord. The prenatal detection rate of TKUC is only 12%. It mostly remains undetected unless visualized incidentally. Although TKUC is not rare and can have serious outcomes, the importance of its antenatal diagnosis has not been determined. It should be suspected in patients with risk factors, and emphasis should be placed on its antenatal diagnosis on ultrasonography to avoid obstetric disasters in otherwise low-risk females. Though there is no specific management of these cases, a good clinical outcome can be achieved if TKUC is diagnosed antenatally and monitored closely until fetal maturity is attained.

Nudo verdadero de cordón umbilical, hallazgo incidental al nacimiento. Reporte de 4 casos en un hospital de tercer nivel / True Umbilical Cord Knot, an Incidental Finding at Birth. Report of 4 Cases in a Third Level Hospital

Resumen El nudo verdadero de cordón umbilical es una patología con una incidencia relativamente baja. Se asocia a riesgo de pérdida del bienestar fetal y muerte perinatal. Existen factores de riesgo tanto maternos como fetales, con diferentes resultados perinatales asociados. El diagnóstico prenatal es un reto para el obstetra y la mayoría de casos son hallazgos al nacimiento, sin embargo, hoy en día se dispone de métodos ecográficos para su búsqueda intencionada, principalmente en pacientes con factores de riesgo. De igual forma debe sospecharse ante la presencia de un registro cardiotocográfico no tranquilizante, sobre todo cuando no existe respuesta a las maniobras habituales de reanimación intrauterina, como la posición en decúbito lateral izquierdo, oxígeno suplementario e hidratación materna. El objetivo del presente reporte es describir 4 casos de nudo verdadero en embarazos a término en un hospital de tercer nivel, en donde se estimó una incidencia del 0.03%, con una edad gestacional promedio de 39.3 semanas y una media de edad materna de 32.2 años. Los principales hallazgos intraparto fueron alteraciones en el registro cardiotocográfico, tales como desaceleraciones variables y tardías. La resolución del embarazo fue por vía vaginal en 2 de las pacientes, mientras que las otras 2 se resolvieron mediante cesárea. Se registró un caso de muerte perinatal.

Abstract The true umbilical cord knot is a pathology with an incidence relatively low. It is associated with the risk of loss of fetal well-being and stillbirth. There are both maternal and fetal risk factors, with different associated perinatal outcomes. Prenatal diagnosis of a true knot is a diagnostic challenge for the obstetrician, however, nowadays it is possible by ultrasound for incidental finding or by intentional search, mainly in patients with risk factors. In the same way it should be suspected in the presence of a non-reassuring cardiotocography, especially when there is no response to the usual intrauterine resuscitation maneuvers, such as left lateral decubitus position, supplemental oxygen and maternal hydration. The purpose of this report is to describe 4 cases of true knot in term pregnancies, in a third level hospital, where an incidence of 0.03% was estimated,, with a mean gestational age of 39.3 weeks and a mean maternal age of 32.2 years. The main intrapartum findings were alterations in the cardiotocography, such as variable and late decelerations. The route of pregnancy resolution was equitable among the patients, 2 were resolved by vaginal delivery and the other 2 by cesarean section. Pregnancy was resolved by vaginal delivery in 2 of the patients, while the other 2 were resolved by cesarean section. One case of stillbirth was registered

Umbilical Cord Knots: Is the Number Related to Fetal Risk?

True knots of the umbilical cord (UC) are a rare occurrence and are reported in 0.4-1.2% of deliveries. The compression of true knot of the UC can cause obstruction of the fetal circulation, leading to intra-uterine growth retardation or fetal death. Predisposing factors for the genesis of the true UC knot are numerous and include all the conditions, which lead to a relatively large uterine volume. This situation may predispose to free and excessive fetal movements. Although not all true knots lead to perinatal complications, they have been associated with adverse pregnancy outcomes, including fetal distress, fetal hypoxia, intra-uterine growth restriction (IUGR), long-term neurological damage, caesarean delivery and stillbirth. We present a rare case of operative delivery with vacuum in a multiparous woman at term of pregnancy with a double true knot of the UC. As in most cases, the diagnosis was made after delivery, as there were no fetal symptoms during pregnancy. Some authors assume that 3D power sonography may be useful in the diagnosis of true UC knots. However, 3D power Doppler cannot be considered as a definitive method. There are no specific prenatal indications to induce the physician to look for ultrasound signs suggestive of umbilical true knot. Some studies argue that cases of fetal death and fetal risk are directly related to the number of knots. We also support this thesis, even if further observational and retrospective studies are needed to demonstrate it.

The perils of true knot of the umbilical cord: antepartum, intrapartum and postpartum complications and clinical implications.

BACKGROUND: True knot of the umbilical cord (TKUC) is found in 0.3-2.1% of pregnancies and is associated with an increased risk of adverse perinatal outcomes. METHODS: A retrospective cohort study including all singleton pregnancies delivered from 2011 to 2019 was performed. Diagnosis of TKUC was made postnatally, immediately after delivery of the baby. Comparison was made between pregnancies with and without TKUC regarding maternal, fetal and neonatal adverse outcome. RESULTS: Overall, 867/85,541 (1%) pregnancies were diagnosed with TKUC. Maternal age, BMI, gravidity and parity were significantly higher in pregnancies with TKUC as well as higher rate of induction of labor, meconium-stained amniotic fluid, and delivery prior to 37 weeks. The rate of cesarean deliveries due to non-reassuring-fetal monitor was significantly higher in pregnancies with TKUC. Overall, there were 2.5% IUFD in pregnancies with TKUC vs. 1% in pregnancies without TKUC (p < 0.001). Importantly, the rate of IUFD prior to 37 weeks of gestation was not significantly higher in the group with TKUC, however, the rate of IUFD after 37 weeks of gestation was 10 folds higher in fetuses with TKUC, 0.9% vs. 0.08% (p < 0.001). Significantly, more neonates with TKUC needed phototherapy or suffered from hypoglycemia. There were no differences in the 5 min Apgar scores, admission to the NICU and number of days of hospitalization. CONCLUSION: Pregnancies complicated with TKUC are associated with a tenfold higher risk of IUFD beyond 37 weeks of gestation. To the results of this study suggest that it would be prudent to induce labor around 37 weeks of gestation in pregnancies with prenatal diagnosis of TKUC. It may be warranted to use continuous fetal monitoring during labor and delivery in those cases were antenatal diagnosis of TKUC is made.

Small bowel obstruction caused by a true ileo-ileal knot: a rare case successfully treated by prior ligation of mesenteric vessels.

BACKGROUND: Intestinal knot formation, in which two segments of the intestine become knotted together, can result in intestinal obstruction. An ileo-ileal knot refers to knot formation between two ileal segments and is a very rare benign disease. We report a case of strangulated bowel obstruction caused by true ileo-ileal knot formation. CASE PRESENTATION: An 89-year-old woman was referred to our hospital with the diagnosis of intestinal obstruction. Contrast-enhanced computed tomography revealed the small bowel forming a closed loop, with poor contrast effect. Based on the findings, the patient was diagnosed as having strangulated bowel obstruction, and emergency surgery was performed. At laparotomy, two segments of the ileum were found to be tied together forming a knot, and both segments were necrotic. Although it was necessary to release the strangulated small bowel, we did not immediately release the knot, but first proceeded with ligation of the mesenteric vessels to the strangulated small bowel to prevent dissemination of toxic substances from the necrotic bowel into the systemic circulation. The surgery was completed with resection of the necrotic ileum and anastomosis of the small intestine. The postoperative course was uneventful, and the patient was discharged home. CONCLUSION: We encountered a case of strangulated bowel obstruction caused by true ileo-ileal knot formation. Resection of the necrotic small intestine without releasing the knot could be performed safely, and might be considered as an option of surgical procedure.

Current Perspectives of Prenatal Sonographic Diagnosis and Clinical Management Challenges of Complex Umbilical Cord Entanglement.

Diagnosis of potential umbilical cord compromise, namely, true knots of the umbilical cord and nuchal cords has been enabled with increasing accuracy with current enhanced prenatal sonography. Often an incidental finding at delivery, the incidence of true knots of the umbilical cord has been estimated at between 0.04% and 3% of deliveries. This condition has been reported to account for a 4 to 10-fold increase of stillbirth and perinatal morbidity of 11% of cases. Nuchal cords, commonly observed at the delivery of uncompromised, non-hypoxic non-acidotic newborns occur more frequently with single nuchal cords noted in between 20% and 35% of all deliveries at term. Multiple nuchal cords are considerably less frequent, with decreasing frequencies inverse to the number of nuchal cord loops. While clearly single (and likely double) nuchal cords are almost uniformly associated with favorable neonatal outcomes, emerging data suggest that cases of ≥3 loops of nuchal cords are more likely to be associated with an increased risk of adverse perinatal outcome (either stillbirth or compromised neonatal condition at delivery). We define cases of a true knot of the umbilical cord, cases of ≥3 loops of nuchal cords, any combination of a true knot and nuchal cord, or any umbilical cord entanglement (nuchal or true knot) in the presence of a single umbilical artery, in singleton gestations as complex umbilical cord entanglement. Two concurrent developments, the increase in accuracy of prenatal sonographic diagnosis of complex umbilical cord entanglement and recent data confirming fatal compromise of the umbilical circulation in approximately 20% of cases of stillbirth, suggest that establishing governing body guidelines for reporting of potential umbilical cord compromise, and recommendation of consideration for early-term delivery of select cases, may be warranted. This commentary will address current perspectives of prenatal diagnosis and clinical management challenges of complex umbilical cord entanglement.

Sono-embryological assessments of a true knot that developed into a hypercoiled cord and circumvallate placenta.

Longitudinal investigations using ultrasound during pregnancy can be used to clarify the mechanisms and pathophysiology of abnormal fetal and placental development. In this report, we presented a case of a true knot that appeared to develop into a hypercoiled cord and circumvallate placenta, which we found through longitudinal ultrasound investigations during pregnancy. In the present case, ultrasonography proved that the true knot had existed at least 16 weeks of gestation. The true knot was presumed to develop into a hypercoiled cord based on the hypothesis of differential umbilical vascular growth rates.

Current Perspectives of Prenatal Sonographic Diagnosis and Clinical Management Challenges of True Knot of the Umbilical Cord.

Umbilical cord accidents preceding labor are rare. Single and multiple nuchal cords, and true knot(s) of the umbilical cord, are often incidental findings noted at delivery of non-hypoxic non-acidotic newborns without any evidence of subsequent adverse neonatal outcome. In contrast to single nuchal cords, true knots of the umbilical cord, which occur in between 0.04% and 3% of all deliveries, have been associated with a reported 4 to 10 fold increased risk of stillbirth. First reported with real-time ultrasound, current widespread application of color Doppler, power Doppler and three-dimension sonography, has enabled increasingly more accurate prenatal sonographic diagnoses of true knot(s) of the umbilical cord. Reflecting the inability to visualize the entire umbilical cord at prenatal ultrasound assessment, despite detailed second and third-trimester scanning, many occurrences of incidental true knot of the umbilical cord remain undetected and are noted only at delivery. Although prenatal sonographic diagnostic accuracy is increasing, false positive sonographic diagnosis of true knot of the umbilical cord cannot be ruled out with certainty, and must continue to be considered clinically. Notwithstanding the inability to diagnose all true knots, currently there is a clear absence of clinical management guidelines by governing bodies regarding patients in whom prenatal sonographic diagnosis of true knot(s) of the umbilical cord is / are suspected. As a result, in many prenatal ultrasound units, suspected sonographic findings suggestive of or consistent with true knot of the umbilical cord are often disregarded, not documented, and patients are not uniformly informed of this potentially life-threatening condition, which carries an associated considerable risk of stillbirth. This commentary will address current perspectives of prenatal sonographic diagnostic and management challenges associated with true knot(s) of the umbilical cord in singleton pregnancies.

The Significance of True Knot of the Umbilical Cord in Long-Term Offspring Neurological Health.

We aimed to study both the short- and long-term neurological implications in offspring born with confirmed knotting of the umbilical cord-"true knot of cord". In this population based cohort study, a comparison of perinatal outcome and long-term neurological hospitalizations was performed on the basis of presence or absence of true knot of cord. A Kaplan-Meier survival curve was constructed to compare the cumulative incidence of neurological hospitalizations between the study groups. Multivariable regression models were used to assess the independent association between true knot of cord, perinatal mortality and long term neurological related hospitalizations, while controlling for potential confounders. The study included 243,639 newborns, of them 1.1% (n = 2606) were diagnosed with true knot of the umbilical cord. Higher rates of intrauterine fetal demise (IUFD) were noted in the exposed group, a finding which remained significant in the multivariable generalized estimation equation, while controlling for confounders. The cumulative incidences of neurological hospitalizations over time were comparable between the groups. The Cox regression confirmed a lack of association between true knot of cord and total long term neurological related hospitalizations. While presence of true knot of the umbilical cord is associated with higher IUFD rates, in our population, however, its presence does not appear to impact the long term neurological health of exposed offspring.

True knot of umbilical cord: Case report and review of literat.

True knot of umbilical cord (TKUC) is a rare abnormality. When it becomes tight, it may lead to the obstruction of the foetal circulation and intrauterine death (IUD). We present two cases of TKUC managed at The Aga Khan University Hospital with two extreme outcomes. A 22 years old primigravida was diagnosed with unexplained intrauterine foetal demise at 28th week gestation. She delivered vaginally after induction and tight TKUC was identified as a cause of IUD. The second patient delivered an alive healthy male baby vaginally who was found to have a lose TKUC.

True umbilical cord knot leading to fetal demise.

The incidence of true knot of the umbilical cord is not only very low but it is often undiagnosed antenatally when present despite the availability of prenatal ultrasonography. When the true knot remains tight, it may impede the circulation of the fetus and may result to fetal death in utero especially in labor. We report a very uncommon case of true knot of the umbilical cord that ultimately led to a fetal demise. A 39-year-old booked G7 P5(+1) with four living children, who booked for antenatal care at a gestational age (GA) of 17 weeks. The fundal height was compatible with the GA throughout pregnancy. An ultrasound done at a GA of 36 weeks showed normal findings. She had onset of labor at a GA of 40 weeks and 5 days following cervical ripening with two courses of 50 µg misoprostol inserted at the posterior fornix 6 h apart. The fetal heart tones were monitored using Doppler sonicaid. They remained normal throughout labor that lasted 13 h. She subsequently had spontaneous vertex delivery with poor Apgar score. The baby died immediately after birth. The umbilical cord was more than double the normal length and a true knot of the umbilical cord was diagnosed after delivery of the baby. We have reported a case of true umbilical cord knot in Nnewi, South-East Nigeria. Although this entity can be diagnosed antenatally, current experience is limited to incidental observation and consequent fetal demise.

Experiencia comunicacional en el diagnóstico y manejo antenatal de nudo del cordón umbilical / Prenatal diagnosis and management of true knot of umbilical cord

Se comunica caso clínico de una madre que consulta en semana 31 de gestación por ausencia de movimientos fetales, y cuyo ultrasonido (US) con escala de grises, Doppler color y tridimensional (3D), demostró imágenes altamente sugerentes de nudo verdadero de cordón umbilical. Se efectuó vigilancia con prueba de movimientos fetales diaria, monitoreo electrónico, hemodinamia fetal y umbilical con doppler, alternados cada tres días, durante siete semanas, demostrando bienestar fetal. Se efectuó operación cesárea cumplida la semana 37 por antecedente de cicatriz uterina previa. El hallazgo intraoperatorio fue una aglutinación de asas del cordón y recién nacido sano. Se discute el diagnóstico falso positivo de nudo por US, el manejo antenatal orientado a la pesquisa oportuna de una eventual oclusión vascular y la experiencia comunicacio-nal con la paciente, que permitió esperar la madurez fetal sin incidentes y con aceptabilidad de la madre, pese al riesgo implícito del diagnóstico presuntivo. Conclusión: En el manejo de alto riesgo se requiere experiencia, apoyo tecnológico y técnicas de comunicación adecuadas con las pacientes, para que una alianza empática permita alcanzar la mayor edad gestacional y la comprensión de un falso positivo.

We report a case of a pregnant woman who presented with absence of fetal movement at the 31st gestational week. The ultrasound (US) images (gray scale, color Dopplerand 3 dimensional) clearly suggested a true knot of the umbilical cord. A close surveillance regime with daily fetal movement test, fetal electronic monitoring and umbilical hemodynamics with Doppler, alternated every three days, was kept for seven weeks, showing fetal wellbeing. At week 37, a cesarean section was performed because of a previous uterine scar. The intraoperative finding confirmed agglutinated and twisted loops, but not a knot of the umbilical cord. The antenatal management is discussed with a close fetal monitoring to detect eventual vascular occlusion in a tight knot and the communication experience with the mother in order to understand and accept a false positive US diagnosis. Conclusion: During a maternal and fetal high risk management is important the professional experience and technological support. On the other hand, the best medical patient communication through an empathetic alliance is required in order to reach a psychological support, longer gestational age and better understanding a false positive test.