New approach for estimating risk of miscarriage after chorionic villus sampling.

OBJECTIVE: To estimate the risk of miscarriage associated with chorionic villus sampling (CVS). METHODS: This was a retrospective cohort study of women attending for routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation at one of eight fetal-medicine units in Spain, Belgium and Bulgaria, between July 2007 and June 2018. Two populations were included: (1) all singleton pregnancies undergoing first-trimester assessment at Hospital Clínico Universitario Virgen de la Arrixaca in Murcia, Spain, that did not have CVS (non-CVS group); and (2) all singleton pregnancies that underwent CVS following first-trimester assessment at one of the eight participating centers (CVS group). We excluded pregnancies diagnosed with genetic anomalies or major fetal defects before or after birth, those that resulted in termination and those that underwent amniocentesis later in pregnancy. We used propensity score (PS) matching analysis to estimate the association between CVS and miscarriage. We compared the risk of miscarriage of the CVS and non-CVS groups after PS matching (1:1 ratio). This procedure creates two comparable groups balancing the maternal and pregnancy characteristics that are associated with CVS, in a similar way to that in which randomization operates in a randomized clinical trial. RESULTS: The study population consisted of 22 250 pregnancies in the non-CVS group and 3613 in the CVS group. The incidence of miscarriage in the CVS group (2.1%; 77/3613) was significantly higher than that in the non-CVS group (0.9% (207/22 250); P < 0.0001). The PS algorithm matched 2122 CVS with 2122 non-CVS cases, of which 40 (1.9%) and 55 (2.6%) pregnancies in the CVS and non-CVS groups, respectively, resulted in a miscarriage (odds ratio (OR), 0.72 (95% CI, 0.48-1.10); P = 0.146). We found a significant interaction between the risk of miscarriage following CVS and the risk of aneuploidy, suggesting that the effect of CVS on the risk of miscarriage differs depending on background characteristics. Specifically, when the risk of aneuploidy is low, the risk of miscarriage after CVS increases (OR, 2.87 (95% CI, 1.13-7.30)) and when the aneuploidy risk is high, the risk of miscarriage after CVS is paradoxically reduced (OR, 0.47 (95% CI, 0.28-0.76)), presumably owing to prenatal diagnosis and termination of pregnancies with major aneuploidies that would otherwise have resulted in spontaneous miscarriage. For example, in a patient in whom the risk of aneuploidy is 1 in 1000 (0.1%), the risk of miscarriage after CVS will increase to 0.3% (0.2 percentage points higher). CONCLUSIONS: The risk of miscarriage in women undergoing CVS is about 1% higher than that in women who do not have CVS, although this excess risk is not solely attributed to the invasive procedure but, to some extent, to the demographic and pregnancy characteristics of the patients. After accounting for these risk factors and confining the analysis to low-risk pregnancies, CVS seems to increase the risk of miscarriage by about three times above the patient's background risk. Although this is a substantial increase in relative terms, in pregnancies without risk factors for miscarriage, the risk of miscarriage after CVS remains low and similar to, or slightly higher than, that in the general population. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Nuevo enfoque para estimar el riesgo de aborto después de una biopsia de vellosidades coriónicas OBJETIVO: Estimar el riesgo de aborto asociado con la biopsia de vellosidades coriónicas (BVC). MÉTODOS: Se trata de un estudio retrospectivo de cohorte de mujeres que acudieron a un examen ecográfico de rutina entre las 11+0 y las 13+6 semanas de gestación a una de entre un total de ocho centros de medicina fetal en España, Bélgica y Bulgaria, entre julio de 2007 y junio de 2018. En el estudio se incluyeron dos poblaciones: 1) todos los embarazos con feto único sometidos a evaluación del primer trimestre en el Hospital Clínico Universitario Virgen de la Arrixaca de Murcia (España), a las que no se les hizo una BVC (grupo no BVC); y 2) todos los embarazos con feto único sometidos a BVC tras la evaluación del primer trimestre en uno de los ocho centros participantes (grupo BVC). Se excluyeron los embarazos diagnosticados con anomalías genéticas o defectos fetales importantes antes o después del nacimiento, los que resultaron en una interrupción y los que más tarde se sometieron a amniocentesis durante el embarazo. Para estimar la relación entre la BVC y el aborto espontáneo se utilizó el pareamiento por puntaje de propensión (PPP). Se comparó el riesgo de aborto de los grupos BVC y no BVC después del pareamiento PPP (razón 1:1). Este procedimiento creó dos grupos comparables en los que las características de la madre y el embarazo que se asocian con la BVC estaban equilibradas, de manera similar a cómo funciona la aleatorización en un ensayo clínico aleatorizado. RESULTADOS: La población de estudio consistió en 22.250 embarazos en el grupo no BVC y 3.613 en el grupo BVC. La incidencia de abortos en el grupo BVC (2,1%; 77/3.613) fue significativamente mayor que en el grupo no BVC (0,9% (207/22.250); P<0,0001). El algoritmo del PPP emparejó 2.122 BVC con 2.122 casos no BVC, de los cuales 40 (1,9%) y 55 (2,6%) embarazos en los grupos BVC y no BVC, respectivamente, resultaron en un aborto espontáneo (razón de momios (RM), 0,72 (IC 95%, 0,48-1,10); P=0,146). Se encontró una interacción significativa entre el riesgo de aborto espontáneo después de una BVC y el riesgo de aneuploidía, lo que sugiere que el efecto de la BVC en el riesgo de aborto espontáneo difiere según las características del contexto. Concretamente, cuando el riesgo de aneuploidía es bajo, el riesgo de aborto después de una BVC aumenta (RM, 2,87 (IC 95%, 1,13-7,30)) y cuando el riesgo de aneuploidía es alto, paradójicamente el riesgo de aborto después de una BVC se reduce (RM, 0,47 (IC 95%, 0,28-0,76)), presumiblemente debido al diagnóstico prenatal y a la interrupción de embarazos con aneuploidías importantes que, de otro modo, hubieran provocado un aborto espontáneo. Por ejemplo, en una paciente para quien el riesgo de aneuploidía es de 1 entre 1000 (0,1%), el riesgo de aborto después de la BVC aumenta al 0,3% (0,2 puntos porcentuales más alto). CONCLUSIONES: El riesgo de aborto espontáneo en las mujeres que se someten a una BVC es aproximadamente un 1% mayor que el de las mujeres a las que no se les hace, aunque este exceso de riesgo no se atribuye únicamente al procedimiento agresivo sino, en cierta medida, a las características demográficas y del embarazo de cada paciente. Después de tener en cuenta estos factores de riesgo y limitar el análisis a los embarazos de bajo riesgo, la BVC parece triplicar aproximadamente el riesgo de aborto en comparación con el riesgo de fondo de la paciente. Aunque se trata de un aumento sustancial en términos relativos, en los embarazos sin factores de riesgo de aborto, después de una BVC el riesgo de aborto sigue siendo bajo y similar, o ligeramente superior, al de la población en general. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Review of electrical impedance tomography in the pediatric patient.

Electrical impedance tomography (EIT) is a new method of monitoring non-invasive mechanical ventilation, at the bedside and useful in critically ill patients. It allows lung monitoring of ventilation and perfusion, obtaining images that provide information on lung function. It is based on the physical principle of impedanciometry or the body's ability to conduct an electrical current. Various studies have shown its usefulness both in adults and in pediatrics in respiratory distress syndrome, pneumonia and atelectasis in addition to pulmonary thromboembolism and pulmonary hypertension by also providing information on pulmonary perfusion, and may be very useful in perioperative medicine; especially in pediatrics avoiding repetitive imaging tests with ionizing radiation.

Gene expression analysis of Chironomus riparius in response to acute exposure to tire rubber microparticles and leachates.

Tire rubber microparticles (TRPs) entering aquatic ecosystems through stormwater runoffs is a significant challenge. TRPs are formed by the abrasion of tires with the road surface and include chemical additives that are an additional cause for concern. Currently, information on the molecular effects of TRPs, or especially its additives, in freshwater organisms is scarce. To address this problem, an array covering different cellular processes has been designed for the freshwater midge Chironomus riparius. Fourth-instar larvae were exposed to two concentrations of TRPs (1 mg L-1, 10 mg L-1) and tire rubber leachates (TRLs) (0,0125 %, 5 %) to evaluate the transcriptional activity by Real-Time PCR. To assess acute toxicity, larvae were exposed for 24 h and genes related to the endocrine system, stress response, DNA repair mechanisms, immune system, oxidative stress, and detoxification mechanisms were evaluated. The activity of the enzymes: glutathione S-transferase (GST) and catalase was also examined. The main pathway affected was the stress response showing overexpression of HSPs (HSC70.3, HSC70.4, HSC70.5, HSP60). Moreover, there was a reduction of the GSTd3 and catalase disrupting the antioxidant system. The upregulation of InR indicates a potential disturbance in the insulin pathway and ABCB6 activation only in TRPs exposure suggests its potential implication in their transport. However, most of these alterations are caused by TRLs, showing higher toxicity than TRPs. The results obtained in this work provide the first approach at the molecular and cellular levels to elucidate the impact of TRLs in freshwater organisms. To perform a realistic evaluation of the TR effects, additional research is required to assess the TR's long-term effects at the molecular level.

Postmarketing study for assessment of tolerability of a grass allergen immunotherapy tablet (GRAZAX) in patients with rhinitis or rhinoconjunctivitis.

BACKGROUND AND OBJECTIVE: Many patients with grass pollen allergy in Spain have concomitant sensitization to other allergens such as profilin. Since this type of sensitization is more common in Mediterranean countries than in countries where most patients were enrolled in clinical trials on GRAZAX (Phleum pratense 75,000 SQ-T/2, 800 BAU, ALK), the aim of this study was to analyze tolerability to GRAZAX under clinical practice conditions in patients with grass pollen allergy. METHODS: A total of 155 patients were enrolled consecutively in a prospective, open-label, observational study. Adverse reactions were recorded during the first month of treatment at 3 different timepoints: after the first dose, when patients were kept under observation for 30 minutes, and on days 15 and 30 after starting treatment RESULTS: With the first dose, 117 adverse reactions were recorded in 63 patients (40.7%). The commonest reactions (>10% patients) were oral pruritus (25.2%) and throat irritation (24.5%). Ear pruritus was recorded in 7.7%. All reactions but 1 occurred within 30 minutes of administration and all were mild-to-moderate. At the end of treatment, the percentage of patients with adverse reactions had decreased significantly (21.3%). Most adverse reactions (95.2%) were mild-to-moderate and only 3 (1.4%) were severe. No serious adverse reactions were recorded. CONCLUSION: GRAZAX seems to be well tolerated, and most reactions were mild-to-moderate. Many of these reactions occur with the first dose. Therefore, according to the Summary of Product Characteristics, the first dose has to be administered under medical supervision.

Perioperative management of patients with arrhythmogenic syndromes refractory to medical treatment: A clinical case report. / Valoración y tratamiento perioperatorio de los pacientes con síndromes arritmogénicos refractarios a tratamiento médico: a propósito de un caso clínico.

Family heart diseases related to sudden death are a group of cardiovascular diseases (cardiomyopathies, channelopathies, aortic diseases...) that require familiarity of the anesthesiologist with the perioperative treatment of complex hemodynamic disorders, as well as their surgical treatment1. We present the case of a 12-year-old man diagnosed with non-obstructive hypertrophic cardiomyopathy, after cardiorespiratory arrest, who underwent video-guided thoracoscopy-guided left sympathectomy for frequent syncope, despite pharmacological treatment and implantation of an implantable automatic defibrillator. Whenever arrhythmic syncope occurs in the setting of familial heart disease, left heart denervation should be considered as the next step in the treatment plan2.

Perioperative management of patients with arrhythmogenic syndromes refractory to medical treatment: A clinical case report.

Family heart diseases related to sudden death are a group of cardiovascular diseases (cardiomyopathies, channelopathies, aortic diseases …) that require familiarity of the anesthesiologist with the perioperative treatment of complex hemodynamic disorders, as well as their surgical treatment.1 We present the case of a 12-year-old man diagnosed with non-obstructive hypertrophic cardiomyopathy (MHNO), after cardiorespiratory arrest (PCR), who underwent video-guided thoracoscopy-guided left sympathectomy (VATS) for frequent syncope, despite pharmacological treatment and implantation of an implantable automatic defibrillator (ICD). Whenever arrhythmic syncope occurs in the setting of familial heart disease, left heart denervation should be considered as the next step in the treatment plan.2.

Original and minimally invasive approach to a left-lung refractory atelectasis after reparation of an aortic recoarctation in a lactant: Selective endobronchial CPAP.

Atelectasis is one of the most common respiratory complications in pediatric patients after open-heart surgery, and may lead to weaning failure and increased morbidity. We report the use of an original, minimally invasive approach to refractory left lung atelectasis after repair of an aortic coarctation in a 2 month-old infant, in which a CPAP system connected to a flexible endobronchial tube resolved the atelectasis.

[Inhaled anesthesia through a device for noninvasive continuous positive airway pressure ventilation for upper digestive endoscopy in pediatric patients]. / Anestesia inhalatoria mediante un dispositivo de ventilación no invasiva tipo "CPAP sin respirador" para endoscopia digestiva alta en pacientes pediátricos.

OBJECTIVE: The demand for sedation for pediatric diagnostic procedures performed outside operating rooms has increased considerably, but the ideal method to choose has been the subject of debate. The aim of this study was to assess the efficacy of using a device for continuous positive airway pressure, connected to a Mapleson D circuit and a nasopharyngeal tube as the interface, in order to ventilate and administer sevoflurane for upper digestive tract endoscopy in children. MATERIAL AND METHODS: Prospective cohort study of children undergoing upper digestive tract endoscopy. We recorded epidemiologic variables, heart rate, mean arterial pressure, arterial oxygen saturation and procedure-related adverse events before, during and 10 minutes after the procedure. Time spent in the recovery room was also recorded. The endoscopist asked the patients about their level of satisfaction and whether they had noticed any irritating smell or gas smell. RESULTS: Data was collected on 29 patients (17 boys, 12 girls) with a mean (SD) age of 4.2 (3.9) years. The mean duration of endoscopy was 15 (7) minutes. Arterial oxygen saturation below 92% during the procedure did not occur and the endoscopic exploration was completed satisfactorily with this technique in 28 patients (96%). All were discharged from the recovery room within 30 minutes. The endoscopist reported that the technique was considered satisfactory in all cases, although 2 children noted an anesthetic "gas" smell. CONCLUSIONS: A modified Mapleson D circuit and nasopharyngeal tube can be used effectively as an interface for noninvasive ventilation and administration of sevoflurane during upper digestive endoscopy in pediatric patients.

[Griscelli-Prunieras syndrome: report of two cases]. / Síndrome de Griscelli-Prunieras: a propósito de dos casos.

Griscelli-Prunieras syndrome (GS) is a rare autosomal recessive disorder characterized by partial albinism. His pathogenic mechanism is associated with defects in the packaging of melanin and other cellular proteins. GS is classified into 3 types based on the genetic and molecular features. Mutations in the genes which cause GS are known. We report two first cases described in Spain who presented a silver-gray sheen of the hair and a severe immune disorder. They were studied for mutations principally related to this syndrome. Two patients showed the Rab27a mutation (frequently associated with GS2). The natural disorder evolution differs considerably among the various forms, so a genetic study is essential in GS to achieve the most accurate prognosis and treatment possible.

[Usefulness of acid-base and electrolyte balance in acute gastroenteritis]. / Utilidad del equilibrio ácido-base y del ionograma en el tratamiento de la gastroenteritis aguda.

INTRODUCTION: Blood analysis blood is frequently requested for evaluating patients with acute gastroenteritis who come to our emergency department, but there are few studies that determine its real usefulness in the management of these patients. OBJECTIVES: a) To determine the reasons why paediatricians request laboratory tests in patients with acute gastroenteritis; b) to establish the type and frequency of laboratory abnormalities found in these patients; c) to evaluate the ability of paediatricians to predict laboratory abnormalities in children with acute gastroenteritis from the history and physical examination; d) to assess the frequency with which these laboratory findings change the initial management of the patient, and e) to determine whether there is an association between clinical and analytical results, and length of hospital stay. PATIENTS AND METHODS: Over a period of 4 months, children between 3 months and 18 years with symptomatic acute gastroenteritis seen in the emergency department and had laboratory tests requested by the paediatrician were included. RESULTS: Of the 4,172 children seen with acute gastroenteritis, 163 patients who had laboratory tests done were included in the study. The most common reason for requests was clinical suspicion of dehydration in 67.5 %. Abnormal results were seen in 77.9 % of cases, mainly metabolic acidosis (72.4 %). The sensitivity analysis to predict an analytical abnormality was 64.6 % with a specificity of 61.1 %. Electrolyte disorders caused a change in the initial management in 12.3 % of patients, with 85.3 % of patients requiring hospital admission; bicarbonate, sodium, creatinine and urea values correlated with a hospital stay of more or less 24 hours. CONCLUSIONS: History and physical examination have limitations in predicting the presence of clinically significant electrolyte abnormalities in patients without clinical signs of dehydration or mild dehydration. Some laboratory tests correlate well with the length of patient stay in hospital.

[Anesthetic induction with nitrous-oxide-free sevoflurane in pediatric patients]. / Inducción anestésica con sevoflurano libre de óxido nitroso en pediatría.

OBJECTIVE: To evaluate the pediatric use of inhaled nitrous oxide (N2O)-free induction with sevoflurane for the purpose of protecting staff from exposure to workplace air pollution. PATIENTS AND METHODS: Prospective, randomized trial in ASA class 1-2 children in whom a tidal breathing technique was used for anesthetic induction in a variety of surgical procedures. Patients were allocated to 2 groups. The sevo-N2O group inhaled 8% sevoflurane in a 60/40% mixture of oxygen and N2O. The sevo-air group received 8% sevoflurane in a mixture of oxygen and air (inspired oxygen fraction, 40%). We recorded mean arterial pressure (MAP), heart rate, oxygen saturation by pulse oximetry (SpO2), limb response to venous puncture, alveolar concentration of sevoflurane, and incidence of adverse events. RESULTS: Twenty-two patients were assigned to each group. The vein was catheterized in all patients without a pain reflex in the limb, and there were no statistically significant differences in MAP, heart rate, SpO2, or incidence of adverse events. Mean (SD) alveolar concentration of sevoflurane, however, differed between the 2 groups: 53% (0.51%) in the sevo-N2O group and 4.91% (0.41%) in the sevo-air group (P = .028). CONCLUSIONS: N2O-free anesthetic induction by tidal breathing of 8% sevoflurane provides similar anesthetic conditions (efficacy, safety, and rapid onset) without a higher incidence of adverse events. The use of N2O can therefore be avoided.

[Electrophysiological effects of sevoflurane in comparison with propofol in children with Wolff-Parkinson-White syndrome]. / Efectos electrofisiológicos del sevoflurano versus propofol en niños con síndrome de Wolff-Parkinson-White.

OBJECTIVE: To evaluate the electrophysiological effects of sevoflurane in children with Wolff-Parkinson-White (WPW) syndrome undergoing radiofrequency ablation. METHODS: We performed a prospective study of 15 patients with WPW syndrome who were scheduled for an electrophysiological study (EPS) and radiofrequency ablation. Anesthesia was induced with fentanyl (2 microg/kg), propofol (3 mg/kg), and vecuronium (0.1 mg/kg), and initially maintained using propofol (100 microg/kg), with bolus administration of fentanyl and vecuronium as required. Four intracardiac catheters were introduced for the EPSpropofol, which included measurements of sinus-node function, sinoatrial-node conduction, refractory periods (atrial, AV-node, accessory pathway anterograde and retrograde, and ventricular), and the characteristics of induced orthodromic tachycardia. The propofol was then replaced with sevoflurane (1 MAC adjusted for age) and the measurements were repeated (EPSsevoflurane). The EPSpropofol and EPSsevoflurane data were compared using the Wilcoxon signed-rank test. RESULTS: The mean (SD) age was 9.3 (6) years. After administration of sevoflurane, the duration of the antegrade effective refractory period of the accessory pathway increased (EPSpropofol, 283 (22) ms; EPSsevoflurane, 298 (25) ms; P = .004), as did the duration of the minimum pacing cycle with 1:1 atrioventricular conduction (EPSpropofol, 244 (41) ms; EPSsevoflurane, 273 (28) ms; P = .028). No significant changes were observed in the other parameters. Ablation of the accessory pathway was achieved in all patients. CONCLUSIONS: Sevoflurane partially modified the properties of the accessory pathway but did not prevent ablation.

[Evaluation of a continuous positive airway pressure system without a ventilator to treat acute respiratory failure in children]. / Evaluación de un dispositivo de CPAP sin respirador en la insuficiencia respiratoria aguda en pediatría.

OBJECTIVE: Noninvasive continuous positive airway pressure (CPAP) is widely used in pediatric patients with acute respiratory failure. However, the lack of specific interfaces and appropriate ventilators and poor tolerance of the technique by these patients can lead to failure of the application. The aim of this study was to analyze the efficacy of a CPAP system using a modified Mapleson breathing circuit during acute respiratory failure in pediatric patients. MATERIAL AND METHODS: We performed a prospective observational study in children with acute respiratory failure in whom noninvasive ventilation was indicated. CPAP was applied through a Mapleson D circuit fitted with a manometer and a nasopharyngeal tube as the interface. Heart rate, respiratory rate, inspired oxygen fraction (FiO2), PaO2, PaCO2, and pulse oximetry were measured before treatment and after 2 hours of treatment. RESULTS: Sixteen patients with a mean age of 3.8 years were studied for a period of 18 months. We observed a mean (SD) change in PaCO2 from 66.8 (18.08) mm Hg to 46.48 (5.9) mm Hg after CPAP (P=.16) and a mean change in the PaO2/FiO2 ratio from 201 (111) to 262 (115) after CPAP (P=.30). The mean heart rate fell from 156 (22) beats/min to 127 (18) beats/min (P=.05) and the mean respiratory rate from 53 (15) breaths/min to 33 (13) breaths/min (P<.05). No severe complications were recorded and tolerance was satisfactory. The technique was considered a success in 12 patients (75%). CONCLUSIONS: CPAP without a ventilator, through a Mapleson D circuit, can be used with a high success rate to provide noninvasive ventilation for pediatric patients with acute respiratory failure.

The importance of bilateral monitoring of cerebral oxygenation (NIRS): Clinical case of asymmetry during cardiopulmonary bypass secondary to previous cerebral infarction. / Importancia de la monitorización bilateral de la oxigenación cerebral: caso clínico de asimetría durante el bypass cardiopulmonar secundaria a infarto cerebral previo.

Cerebral oximetry based on near infrared spectroscopy (NIRS) technology is used to determine cerebral tissue oxygenation. We hereby present the clinical case of a 12-month old child with right hemiparesis secondary to prior left middle cerebral artery stroke 8 months ago. The child underwent surgical enlargement of the right ventricular outflow tract (RVOT) with cardiopulmonary bypass. During cardiopulmonary bypass, asymmetric NIRS results were detected between both hemispheres. The utilization of multimodal neuromonitoring (NIRS-BIS) allowed acting on both perfusion pressure and anesthetic depth to balance out the supply and demand of cerebral oxygen consumption. No new neurological sequelae were observed postoperatively. We consider bilateral NIRS monitoring necessary in order to detect asymmetries between cerebral hemispheres. Although asymmetries were not present at baseline, they can arise intraoperatively and its monitoring thus allows the detection and treatment of cerebral ischemia-hypoxia in the healthy hemisphere, which if undetected and untreated would lead to additional neurological damage.

Cerebral oximetry monitoring in the management of severe hypoxaemia associated with transposition of the great arteries with balloon atrial septostomy. / Monitorización de la oximetría cerebral en el manejo de la hipoxemia severa asociada a la transposición de grandes arterias mediante atrioseptostomía con balón.

Transposition of the great arteries (D-TGA) is one of the most common congenital heart diseases requiring neonatal surgical intervention. In the desperately ill neonate with TGA and the resultant hypoxaemia, acidemia, and congestive heart failure, improvement is often obtained with balloon atrial septostomy (BAS). Current methods employed to evaluate oxygen delivery and tissue consumption are frequently nonspecific. Near infrared spectroscopy (NIRS) allows a continuous non-invasive measurement of tissue oxygenation which reflects perfusion status in real time. Because little is known about the direct effect of BAS on the neonatal brain and on cerebral oxygenation, we measured the effectiveness of BAS in two patients with D-TGA using NIRS before and after BAS. We concluded BAS improves cerebral oxygen saturation in neonates with D-TGA.

Cardiac arrest related to anaesthesia in Williams-Beuren syndrome. / Parada cardíaca relacionada con la anestesia en el síndrome Williams-Beuren.

Williams-Beuren syndrome is the clinical manifestation of a congenital genetic disorder in the elastin gene, among others. There is a history of cardiac arrest refractory to resuscitation manoeuvres in anaesthesia. The incidence of myocardial ischaemia is high during anaesthetic induction, but there are patients who do not have this condition yet also have had very serious cardiac events, and issues that are still to be resolved. Case descriptions will enable the common pathophysiological factors to be defined, and decrease morbidity and mortality. We report the case of a 3-year-old boy with cardiac arrest at induction, rescued with circulatory assistance with extracorporeal membrane oxygenation and hypothermia induced for cerebral protection.

[Effect of tranexamic acid on postoperative bleeding in pediatric heart surgery]. / Efecto del ácido tranexáimico en el sangrado postoperatorio de cirugía cardiaca en pediatría.

OBJECTIVE: To assess the effects of a single dose of tranexamic acid on bleeding and requirement for blood product transfusion in children undergoing cardiac surgery with cardiopulmonary bypass. PATIENTS AND METHODS: A prospective study of closed cohorts undergoing pediatric heart surgery was carried out. The children weighed between 4 and 10 kg. Reoperated and cyanotic patients were included in the sample. The treatment group received 50 mg x kg(-1) of tranexamic acid before surgery. Analyzed data collected during the first 24 hours after surgery were biochemical parameters, bleeding, use of blood products, and D-dimer levels. RESULTS: Fifty-three patients, 25 in the treatment group, were enrolled. Patients on treatment had 24.8% less bleeding in the first 24 hours after surgery (P = .02). The transfusion of blood products was 20% less in the treatment group, although the difference was not significant except in the subgroup of patients who were reoperated. In that group the amount of blood products transfused was 72% less than in the control group (P = .05). D-dimer levels were also lower in the treatment group (P = .003). No adverse effects attributable to the treatment were observed. CONCLUSIONS: A single preoperative dose of tranexamic acid to inhibit fibrinolysis reduces bleeding 24.8% in pediatric patients undergoing heart surgery with cardiopulmonary bypass. The effect is greater in reoperated patients, leading to a reduction in their requirement for transfusion. The use of this therapy in these patients is therefore highly justified.