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.

Anestesia cardiovascular en cirugía no cardiaca / Cardiovascular anesthesia in noncardiac surgery

Clinical evaluation remains one of the main issues while considering anesthetic and surgical risk. Different scores for cardiac evaluation in non-cardiac surgery are traditionally based on the exclusion of active cardiac conditions, the risk of surgery, the functional capacity of the patient and the presence of specific cardiac risk factors. In recent decades, new guidelines incorporate an association between cardiac biomarkers and adverse cardiac events. For the management of coronary patients receiving double antiplatelet therapy, derived for non-cardiac surgery, the risk of stent thrombosis, the consequences of delaying the surgical procedure and the risk of bleeding must be considered. At this moment, there is no evidence regarding which is the best anesthetic management that decreased peri-operative cardiovascular complications in this group of patients. This article refers to the differences in preoperative assessment for non-cardiac surgery incorporated in the guidelines of the American College of Cardiology, the American Heart Association, the European Society of Cardiology and the Canadian Cardiovascular Society. Consideration are also given to the management of coronary patients on double antiplatelet therapy and its main complications as well as intraoperative management maneuvers that may decrease cardiovascular complications.

La valoración clínica sigue siendo uno de los pilares fundamentales en la evaluación del riesgo anestésico-quirúrgico. Los scores de riesgo para la evaluación cardiovascular y cirugía no cardíaca se basan tradicionalmente en la exclusión de condiciones cardíacas activas, la determinación del riesgo de cirugía, la capacidad funcional del paciente y la presencia de factores de riesgo cardíaco. En las últimas décadas, nuevas guías incorporan una asociación entre los biomarcadores cardiacos y los eventos cardiacos adversos. Para el manejo de pacientes coronarios en tratamiento antiagregante doble, derivados a cirugía no cardiaca, hay que considerar el riesgo de trombosis del stent, las consecuencias de retrasar el procedimiento quirúrgico y el aumento del riesgo de hemorragia. Hasta la fecha no existe evidencia acerca de cuál es el mejor manejo anestésico que disminuya las complicaciones cardiovasculares perioperatorias en este grupo de pacientes. Este artículo, hace referencia a las diferencias de la valoración preoperatoria para cirugía no cardiaca incorporados en las guías del American College of Cardiology, la American Heart Association, la European Society of Cardiology y la Canadian Cardiovascular Society. Algunas consideraciones acerca del manejo de pacientes coronarios, terapia antiplaquetaria dual y eventuales complicaciones. Se incluyen algunas estrategias farmacológicas, así como consideraciones específicas para el perioperatorio, con el fin de reducir morbilidad de origen cardiovascular.

Implante percutáneo de válvula aórtica con apoyo de circulación extracorpórea en paciente con insuficiencia aórtica severa / Trans catheter aortic valve implantation with extra corporeal circulation support in a patient with severe aortic insufficiency

An 84-year man with prior coronary artery bypass surgery and endovascular repair of an abdominal aortic aneurysm developed congestive heart failu-re. He had calcific aortic valve disease with severe regurgitation. A #29 Edwards-Sapien aortic valve via trans-apical approach was implanted with the patient connected to extra corporeal circulation. The patient recovered successfully and remained in functional class II 8 months after hospital dis-charge.

Tratamiento endovascular exitoso de aneurisma de aorta torácica secundario a infección de catéter de arteria umbilical en un recién nacido pretérmino / Successful endovascular treatment of thoracic aortic aneurysm secondary to infection of the umbilical artery catheter in preterm infants

Los aneurismas aórticos en la población pediátrica son poco frecuentes. El uso de catéteres de arteria umbilical en neonatos se ha asociado a infección y en algunas oportunidades a formación de aneurismas aórticos. La reparación quirúrgica de estos aneurismas es una forma de terapia; sin embargo, la intervención percutánea con stents pudiese proveer una vía alternativa de tratamiento con menores complicaciones. El objetivo de este reporte es dar a conocer el alcance terapéutico de un procedimiento híbrido, en el que el desarrollo de la técnica quirúrgica y percutánea en conjunto ofrece otra alternativa terapéutica menos invasiva que la cirugía vascular abierta, para la reparación de aneurismas aórticos o de sus ramas principales. Caso clínico: Recién nacido de pretérmino, 30 semanas, peso 1.335 g. Se instaló catéter en arteria umbilicar que se retiró a los 14 días por infección. Evolucionó con sepsis a Staphylococcus aureus. Ecocardiograma y angiotac confirman AAT, se manejó mediante procedimiento híbrido, cirugía e instalación endovascular de 2 stents recubiertos (Atrium V12 XR Medical Corp, Hudson, NH). Los controles clínicos post procedimiento como la ecotomografía abdominal confirmaron el éxito del tratamiento. Conclusión: El procedimiento endovascular de reparación de aneurisma de la aorta en recién nacidos prematuros puede ser considerado en el momento de decir la terapéutica de esta enfermedad y podría evitar los riesgos asociados a cirugía abierta. Sin embargo, obliga a un seguimiento y control durante el crecimiento del paciente por la eventual necesidad de redilatar los stents implantados. Se desconoce cómo será la evolución de los procedimientos endovasculares neonatales en el futuro.

Aortic aneurysms (AA) in the paediatric population are uncommon. The use of umbilical catheters in neonates has been associated with infections and, on some occasions, the formation of aortic aneurysms. The surgical repair of these aneurysms is one type of treatment; however, percutaneous intervention with stents could provide an alternative treatment route, with fewer complications. The aim of this report is to present the therapeutic scope of a hybrid procedure, in which the combined surgical and percutaneous technique offers a less invasive alternative to open surgery for the repair of aortic aneurysms or their main branches. Clinical case: The case concerns a pre-term newborn of 30 weeks weighing 1,335 g. An umbilical catheter was introduced, which was withdrawn at 14 days due to an infection. It developed as Staphylococcus aureus with sepsis. The echocardiogram and Angio-CT confirmed AA, which were managed using a hybrid procedure of surgery and the endovascular implantation of 2 coated stents (Atrium V12 XR Medical Corp, Hudson, NH). The post-procedure clinical follow-ups, including abdominal echo-tomography, confirmed the success of the treatment. Conclusion: The endovascular aortic aneurysm repair procedure in premature newborns may be considered when deciding treatment of this disease, and could avoid the risks associated with open surgery. However, follow-up and monitoring is required while the patient grows up, due to the possibility that the implanted stents require re-dilating. The outcomes of neonatal endovascular procedures in the future are unknown.

Analgesia, sedación y anestesia para cateterismo diagnóstico y/o terapéutico en pacientes pediátricos con cardiopatías congénitas en el Hospital Clínico de la Pontificia Universidad Católica de Chile: algunas recomendaciones / Analgesia, sedation and anesthesia in diagnostic or therapeutic catheterization in pediatric patients with congenital heart disease

Las presentes recomendaciones han sido elaboradas en base a nuestra experiencia, con el propósito de entregar algunas pautas sobre analgesia, sedación y anestesia para cateterismos diagnósticos y/o terapéuticos en pacientes pediátricos con cardiopatías congénitas, de acuerdo a la clasificación de riesgo de los mismos. El propósito de ésta es contribuir a disminuir la incidencia de eventos adversos asociados a morbilidad y mortalidad.

Recommendations based con clinical experience with analgesia, sedation and anesthesia in diagnostic or therapeutic cardiac catheterization in pediatric patients with congenital heart disease are outlined. These recommendations, based on clinical experience at a single institution (Catholic University Hospital in Santiago, Chile) are intended to help reduce de incidence of adverse effects, morbidity and mortality in this patient population.

Resultados inmediatos y alejados del switch arterial en pacientes condextrotransposición de grandes arterias: experiencia de 20 años / Early and late results of the switch operation for d-transposition of the great vessels. clinical experience in 108 patients operated on between 1992 and 2012

Objetivos: Comunicar los resultados de la operación de switch arterial en pacientes portadores de dextro Transposición de Grandes Arterias (D-TGA) y evaluar su evolución en el tiempo. Pacientes y Método: Estudio retrospectivo de pacientes sometidos a switch arterial entre mayo de 1992 y noviembre de 2012. Se comparó período 1 (1992 a 2002) con período 2 (2003 a 2012). Se definió D-TGA simple aquella sin lesiones asociadas y D-TGA compleja aquella con asociación de comunicación interventricular o coartación aórtica. Resultados: Un total de 108 pacientes componen la serie, 44 en el período 1 y 64 en el período 2, sin diferencias demográficas y anatómicas entre ambos períodos. Setenta tenían D-TGA simple y 38 D-TGA compleja. La mortalidad operatoria en el período 1 fue 33% versus 8,4 por ciento en el período 2 (p< 0.025); hubo tendencia a mayor mortalidad en pacientes con anatomía coronaria compleja. Se observó una disminución del riesgo relativo de mortalidad de 68,7 por ciento en el período 2. El 28,7 por ciento presentaron complicaciones postoperatorias, sin diferencias entre ambos períodos. Un paciente falleció en forma alejada. La mediana de seguimiento fue de 60 meses y la supervivencia de 84,25 por ciento a 10 y 20 años. Se realizaron 16 re intervenciones, principalmente plastías percutáneas de ramas pulmonares. La mayoría de los pacientes se mantenían asintomáticos. La mortalidad operatoria de los últimos 5 años fue 2,6 por ciento. Conclusiones: La mortalidad operatoria ha disminuido significativamente a lo largo de 20 años; persiste un mayor riesgo en ciertos patrones de anatomía coronaria. La supervivencia alejada y libre de reintervenciones es muy favorable.

Aim: to report the results of the arterial Switch operation in patients with D-transposition of the great vessels (D-TGA) and to evaluate their late course. Patients and Methods: A retrospective review of the clinical data on patients consecutively operated on for D-TGA using the switch procedure. Results obtained in patients operated on between 1992 and 2002 (Period 1) were compared to those obtained in patients undergoing their operation between 2013 and 2012. Patients with D-TGA and no complications were compared to those who had interventricular septal defect or aortic coarctation associated their TGA. Results: 44 patients belonged in Period 1 and 64 in Period 2 (total 108). Demographic and anatomical characteristics were similar in both periods. Simple D-TGA was present in 70 patients and complex D-TGA in 38. Operative mortality was higher in Period 1 compared to Period 2 (33 per cent vs. 8.4 percent, p<0.025). A higher, albeit not statiscally significant mortality was observed in patients with complex as opposed to simple D-TGA. A 68.7 per cent relative reduction mortality risk was observed in Period 2. Complications developed in 28.7 per cent of patients, with no difference between periods. Only 1 patient died during late follow up. Median follow up was 60 months and survival rate was 84.3 percent at 10 y 20 years. Sixteen patients required re-intervention, mainly to perform percutaneous plastic procedures on pulmonary artery branches. Most patients had an asymptomatic course during follow up. Surgical mortality for the last 5 years was 2.6 percent. Conclusion: surgical mortality for the arterial switch operation in patients with D-TGA has significantly decreased along a 20 year period. An increased surgical risk persists for patients with certain forms of coronary artery anomalies. Late survival free of re-intervention was the rule in these patients.

Cirugía cardiaca con circulación extracorpórea: síndrome vasoplégico y vasopresina / Vasoplegic syndrome and its treatment with vasopressin during cardiac surgery with cardiopulmonary bypass

Cardiac surgery with cardiopulmonary bypass is associated with systemic inflammatory response. In some cases this clinical condition is characterized by severe hypotension due to low systemic vascular resistance during and after cardiopulmonary bypass. Afew ofthese cases do not respond to volume or catecholamines. This condition is known as vasoplegic syndrome. Its etiology is notfully understood today and carries associated morbidity and mortality In this syndrome, vasopressin levéis are reduced, as in septic and hypovolemic shock. Supplementary vasopressin improves blood pressure and might be considered as an alternative treatment. Severa! reports have shown benefits when used alone or in combination with catecholamines. However, further studies are necessary to find the most appropriate use ofthe drug for vasoplegic syndrome.

Reparación endovascular de aneurisma aórtico abdominal: estudio piloto de endoprótesis Ovation™: resultados comparativos / Endovascular repair of abdominal aortic aneurysm: comparative results of a pilot study using the Ovation™ prosthesis

Introducción: Las endoprótesis actuales para tratar aneurismas aórticos (AAA) requieren introductores de alto diámetro (18-25F) y se sustentan excluyendo el aneurisma, mediante la fuerza radial de stents metálicos. Objetivo: prótesis Ovation™ (TriVascular, EEUU) con aquellas disponibles en el mercado. Material y Método: Entre Noviembre 2009 y Agosto 2010 tratamos 47 AAA. En 10 pacientes usamos Ovation™ (Grupo 1). Grupo Control (2): diez pacientes tratados contemporáneamente con endoprótesis comerciales. Ovation™ es tri-modular, de PTFE y nitinol con un stent barbado para fijación supra-renal. Sella bajo las arterias renales mediante 2 anillos llenados con un polímero durante el implante. Usa introductor 13-15F. Usa-Philips-Allura (Best, Holanda). Comparamos: duración del procedimiento, hospitalización y complicaciones. Utilizamos test de Fisher exacto y t de student no pareado. Resultados: Éxito técnico 100 por ciento. Sin diferencia entre grupos (edad, sexo, tamaño AAA, riesgo ASA, laboratorio preoperatorio). Tiempo operatorio (hrs): 2,12 +/- 0,7 vs. 2,0 +/- 0,6 (NS). Estadía postoperatoria (hrs): 44,5 +/- 10,7 vs 49,5 +/- 32,0 (NS). El cuello del AAA y la permanencia en UTI fueron más cortos en grupo 1 (p= 0,035 y 0,0451). Seguimiento (4,5-12 meses) sin eventos adversos, endofugas tipo I ni III, ni re-intervenciones. Conclusiones: Los resultados con Ovation™ a corto plazo son comparables con los de otras endoprótesis, cumpliendo con estándares de eficacia y seguridad. Ovation ™ navega por vasos pequeños, permite un despliegue preciso y sellado efectivo en cuellos > 7 mm, ampliando el tratamiento endovascular del AAA.

Background. Current endografts used in treatment of abdominal aortic aneurysm (AAA), use large (18-25F) delivery systems. Graft fixation and aneurysm sealing is obtained by a proximal stent, requiring an aortic neck >15 mm. Objective. To compare the efficacy and safety of Ovation™ endograft (TriVascular, USA) with standard endografts. Methods. Between November 2009 and August 2010 we treated 47 AAA. In 10 patients we used Ovation™ (Group 1). Ten patients treated during the same period with commercially available endografts were used as controls (Group (2). The Ovation™ endo-prosthesis is tri-modular, made of PTFE andnitinol with low profile (13-15F) and has a barbed suprarenal stent for fixation. Sealing is obtained independently through 2 inflatable rings filled with a biocompatible polymer during the procedure. Implantation followed the standard procedure through femoral exposure, using the Philips Allura imaging equipment (Best, Netherlands). Procedure duration, length of stay (LOS) and complications were compared between groups. Fisher exact test and unpaired Student’s t test were used for comparisons. Results. Results. Technical success was 100 percent. We observed no difference between groups (age, sex, AAA size, ASA risk, preoperative lab work). Procedure time (hrs) was 2,12 +/- 0,7 vs. 2,0 +/- 0,6 (NS), LOS (hrs) was 44,5 +/- 10,7 vs. 49,5 +/- 32,0 (NS) in Groups 1 and 2, respectively. Aneurysm neck length and ICU stay were shorter in Group 1 (p= 0,035 and 0,0451 respectively). During a 12 month follow up no adverse events, type I or III endoleak, or secondary interventions have occurred. Conclusion. Results with Ovation™ are comparable to other endografts currently available, achieving the same standards of efficacy and safety. Its highly flexible delivery system allows navigation through small vessels, easy deployment and effective sealing of AAA with necks > 7 mm, broadening the span of patients suitable for endovascular treatment.

Función renal en cirugía cardíaca con circulación extracorpórea: Pacientes valvulares y coronarios / Renal function during cardiac surgery with extracorporeal circulation

Background: Patients with valvular heart disease are at high risk of acute renal failure after surgery with extracorporeal circulation. Aim: To describe changes in renal function parameters during surgery with extracorporeal circulation in patients with valvular heart disease and compare them with those found in patients undergoing elective coronary surgery Material and Methods: Two groups of patients were studied. Group 1 was composed by twelve patients undergoing elective coronary surgery and group 2 was composed by eleven patients undergoing surgery for heart valve replacement. Glomerular filtration rate and effective renal plasma now were estimated from inulin and the 131 I-hippuran clearance respectively, at five different times, during surgery and the postoperative period. Sodium filtration fraction and fractional excretion were calculated. Alpha and pi-glutathione s-transferase in urine were measured as markers of tubular damage in the pre and postoperative periods. Results: Effective renal plasma flow was reduced in both groups before induction of anesthesia, did not change during surgery and decreased significantly in patients with valvular disease in the postoperative period. Glomerular filtration rates were normal during all the study period. There was a non significant reduction of filtration fraction during extracorporeal circulation. Alpha and pi glutathione s-transferases were normal and did not change. Fractional excretion of sodium increased significantly postoperatively Conclusions: In patients with valvular disease undergoing surgery with extracorporeal circulation, renal function does not deteriorate. No significant difference was found when compared with patients undergoing coronary surgery. No evidence of functional and cellular renal disfunction or damage was found in both study groups.

Práctica transfusional en pacientes adultos sometidos a cirugía cardíaca con circulación extracorpórea: experiencia de la Pontificia Universidad Católica de Chile / Prediction of blood transfusion need in patients undergoing open heart surgery: the experience of Catholic University Hospital, Chile

Antecedentes: La cirugía cardíaca se asocia a un alto consumo de sangre homóloga. Si conocemos los factores quepredicen una mayor necesidad de transfusión, podremos implementar mejores estrategias de ahorro sanguíneo. Objetivo: Describir la práctica transfusional en pacientes adultos sometidos a cirugía con circulación extracorpórea (CEC) en la Pontificia Universidad Católica de Chile. Materiales y métodos: Se recolectaron en forma retrospectiva los datos de 194 pacientes adultos sometidos a cirugía cardíaca con CEC, entre octubre de 2003 y marzo de 2004. Se realizó una descripción de la práctica transfusional y un análisis de riesgo uni y multivariado. Resultados: El 61,8 por ciento de los pacientes se transfundieron durante la hospitalización. La transfusión intraoperatoria se relacionó con sangrado y la transfusión postoperatoria con la corrección de un hematocrito bajo. Los factores predictores de transfusión fueron cirugía de urgencia, tiempo prolongado de CEC, edad avanzada y un menor hematocrito al momento de ingresar a la unidad de cuidado postoperatorio. El hematocrito bajo al inicio de la cirugía, una menor temperatura durante CEC y un mayor sangrado en el postoperatorio predijeron el uso de más de dos unidades de glóbulos rojos (GR).Los pacientes que recibieron más de 2 unidades de GR presentaron en forma significativa mayor incidencia de neumonía, insuficiencia respiratoria y sepsis. Conclusiones: La transfusión sanguínea en cirugía cardíaca se relaciona directamente con la complejidad de los pacientes y los procedimientos. Las técnicas de ahorro de sangre deben dirigirse hacia la disminución del sangrado, la hemodilución y a estrictos criterios de transfusión intra y postoperatorios.

Background: Cardiac surgery is associated with frequent use of homologous blood. The knowledge of factors that influence the need for transfusion might help us implement strategies to avoid unnecessary blood administration. Objective: To describe the current transfusion practices in adults undergoing open cardiac surgery with extra corporeal circulation (ECC) at the Pontificia Universidad Católica of Chile Hospital. To identify factors that predict the use of transfusion. Methods: Data from 194 adult patients submitted to cardiac surgery with ECC between October 2003 and March 2004 were obtained retrospectively. Transfusional practices were identified. Uni and multivariate risk analysis was used to predict the need for transfusion.Results: 61,8 percent of patients were transfused during their hospital stay. Intraoperative transfusion was related to bleeding while post operative transfusion was performed to correct a low hematocrit value. Factors predicting transfusion were: emergency surgery, prolonged EEC time, older age and lower hematocrit value when entering the ICU. Preoperative hematocrit, lower temperature during ECC and post operative bleeding predicted the use of more than 2 red blood cell (RBC) packs. Patients receiving more than 2 RBC packs had a significantly higher incidence of pneumonia, sepsis and respiratory failure. Conclusion: Blood transfusion during cardiac surgery is directly related to complexity of procedures and severeness of patient illness. Blood saving techniques must be directed to reducing the amount of bleeding, allowing hemodilution and defining strict criteria for intra and post operative transfusions.