Acceso venoso difícil en pediatría / Difficult venous access in pediatrics

BACKGROUND: Cannulation of a peripheral venous access is a routine procedure in pediatric patients admitted to the hospital. 50% of the time cannulation on the first attempt is not feasible, so it is necessary to repeat the puncture, resulting in a complex and frustrating procedure. Half of the children admitted to the hospital have a difficult venous access (DIVA). OBJECTIVE: To carry out a review, which provides information about DIVA in pediatrics, how to evaluate and proceed in these patients. DESIGN: DIVA Score considers vein palpability, vein visibility, age and history of prematurity. The score ranges from 0 to 10 points. Values greater than 4 are associated with difficult venous access. There are associated risk factors: obesity, musculoskeletal malformations, chemotherapy treatment, diabetes mellitus, patients on dialysis, limb edema, moderate to severe dehydration, history of difficult venous access, anxiety of the patient and/or parents report that the child is less likely to cooperate. When making the decision to establish a venous access, it should be evaluated whether it is an emergency or not, the characteristics of the medications and infusions, the time of therapy and the anatomical sites for puncture. Ultrasound and transillumination techniques decrease the time to obtain a venous access and increase the success rate on the first attempt. CONCLUSION: The decision to obtain a venous access must take into account the criteria and risk factors for DIVA. The most recognized scale is the DIVA Score.

INTRODUCCIÓN: La canulación de un acceso venoso periférico es un procedimiento rutinario en los pacientes pediátricos que ingresan al hospital. 50% de las veces la canulación al primer intento es frustra, por lo que es necesario repetir la punción resultando el procedimiento complejo y frustrante. La mitad de los niños que ingresa al hospital presentan un acceso venoso difícil (DIVA, sigla derivada de "difficult intravenous access"). OBJETIVO: Realizar una revisión, que entrega información acerca de DIVA en pediatría, cómo evaluar y proceder en estos pacientes. DESARROLLO: DIVA Score considera palpabilidad y visibilidad venosa, edad y antecedente de prematurez. El puntaje va desde 0 a 10 puntos. Valores mayores a 4 se asocian a acceso venoso difícil. Existen factores de riesgo asociados: obesidad, malformaciones osteomusculares, tratamiento con quimioterapia, diabetes mellitus, pacientes en diálisis, edema de extremidades, deshidratación moderada a severa, historia de acceso venoso difícil, ansiedad del paciente y/o padres que refieren que el niño es poco probable que coopere. Al tomar la decisión de establecer un acceso venoso se debe evaluar si es urgencia o no, las características de los medicamentos e infusiones, tiempo de terapia y los sitios anatómicos para punción. La ultrasonografía y las técnicas de transiluminación disminuyen el tiempo de obtención del acceso venoso e incrementan la tasa de éxito en el primer intento. CONCLUSIÓN: En la decisión de obtener un acceso venoso se deben tener en cuenta los criterios y factores de riesgo de acceso venoso difícil. La escala más reconocida es el DIVA Score.

Aortic stenosis and acquired von Willebrand disease: lack of association.

OBJECTIVES: The association between aortic stenosis (AS) and acquired von Willebrand disease type 2A has been described. It may be present in up to 90% of patients with AS. Shear stress has been proposed as the underlying mechanism; however, the physiopathology of this condition is not completely understood. No specific treatment has been studied in this specific population besides aortic valve replacement (AVR). As a coadjuvant therapy, some cardiac surgery centers use desmopressin routinely. The authors report the first stage of an ongoing study designed to compare the effects of desmopressin versus placebo in patients with severe AS scheduled for AVR. Because of the different incidences of the acquired von Willebrand type 2A reported in the literature, the first stage was conducted to describe the incidence of this clinical association in the present population, allowing the sample size for the second stage of the study to be obtained. DESIGN: A prospective cohort study. SETTING: A single academic medical center. PARTICIPANTS: Thirteen patients with severe AS scheduled for AVR. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Patients with severe AS scheduled for AVR were studied preoperatively with a von Willebrand laboratory panel. Results were negative for acquired von Willebrand disease type 2A in all patients. The second stage of the trial was stopped. CONCLUSION: Contrary to previous reports, no correlation was found between AS and acquired von Willebrand disease type 2A. Further studies are needed to ascertain whether this lack of association is caused by a specific characteristic of the present population, the small sample size, or other factors.