[Experience with the Norwood operation for hypoplastic left heart syndrome]. / Resultados de la intervención de Norwood para el síndrome del corazón izquierdo hipoplásico.

INTRODUCTION AND OBJECTIVES: To describe our experience and to identify risk factors for in-hospital mortality. METHODS: Between October 1991 and June 2005, 42 children underwent the Norwood procedure. In the first 30 patients, pulmonary circulation was established using a modified Blalock-Taussig shunt (Group 1), while a right ventricle to pulmonary artery conduit was used in the remaining 12 (Group 2). Preoperative anatomic features and procedural factors were analyzed with respect to their impact on mortality. Postoperatively, data were collected on arterial blood pressure, arterial and venous oxygen saturation, arterial pH, venous pCO2, the PaO2/FiO2 ratio, tissue oxygen extraction, and dead space fraction. The association between each individual variable and mortality was investigated. RESULTS: Thirty patients (71.4%) had both aortic and mitral atresia, eight (19%) had either aortic or mitral atresia, and four (9.5%) had no valvular atresia. There was no statistically significant difference in postoperative mortality between the groups 1 and 2 (12/22 [54.5%] vs 7/12 [58.3%]; P=.56). The only significant risk factor for in-hospital mortality was a longer cardiopulmonary bypass time (P=.01) and, for intraoperative mortality, primary rather than delayed sternal closure (P=.004). Venous pCO2, the mean dead space fraction, and tissue oxygen extraction all tended to be higher among infants who died, but the difference was not statistically significant. CONCLUSIONS: Use of a right ventricle to pulmonary artery conduit did not improve postoperative survival. Both a long cardiopulmonary bypass time and primary sternal closure were associated with increased mortality.

Resultados de la intervención de Norwood para el síndrome del corazón izquierdo hipoplásico / Experience with the norwood operation for hypoplastic left heart syndrome

Introducción y objetivos. Describir nuestra experiencia e identificar factores de riesgo de mortalidad hospitalaria. Métodos. Entre octubre de 1991 y junio de 2005 intervinimos a 42 niños con la técnica de Norwood. Los 30 primeros recibieron una fístula de Blalock-Taussig (grupo 1) y los 12 restantes, un conducto entre el ventrículo derecho y la arteria pulmonar (grupo 2). Se analizaron los factores anatómicos y de la técnica con respecto a la mortalidad. Se recogieron variables del postoperatorio, incluidas la presión arterial, la saturación arterial y venosa de oxígeno, el pH arterial, la pCO2 venosa, la relación PaO2/FiO2, la extracción tisular de oxígeno y el espacio muerto, para estudiar su asociación con la mortalidad. Resultados. En total, 30 (71,4%) pacientes tenían atresia aórtica y mitral; 8 (19%) tenían atresia aórtica o mitral y 4 (9,5%) no tenían atresia. No hubo diferencias significativas en la mortalidad postoperatoria entre los grupos 1 y 2 (12/22 [54,5%] frente a 7/12 [58,3%]; p = 0,56). El único factor de riesgo de mortalidad hospitalaria fue un tiempo de circulación extracorpórea prolongado (p = 0,01), y el de mortalidad intraoperatoria, el cierre primario del esternón (p = 0,004). La pCO2 venosa, el espacio muerto pulmonar y la extracción tisular de oxígeno fueron superiores en los niños fallecidos, pero las diferencias no fueron significativas. Conclusiones. El uso de un conducto entre el ventrículo derecho y la arteria pulmonar no mejoró la supervivencia postoperatoria. Un tiempo de circulación extracorpórea prolongado y el cierre primario del esternón se asociaron con un aumento de la mortalidad (AU)

Introduction and objectives. To describe our experience and to identify risk factors for in-hospital mortality. Methods. Between October 1991 and June 2005, 42 children underwent the Norwood procedure. In the first 30 patients, pulmonary circulation was established using a modified Blalock-Taussig shunt (Group 1), while a right ventricle to pulmonary artery conduit was used in the remaining 12 (Group 2). Preoperative anatomic features and procedural factors were analyzed with respect to their impact on mortality. Postoperatively, data were collected on arterial blood pressure, arterial and venous oxygen saturation, arterial pH, venous pCO2, the PaO2/FiO2 ratio, tissue oxygen extraction, and dead space fraction. The association between each individual variable and mortality was investigated. Results. Thirty patients (71.4%) had both aortic and mitral atresia, eight (19%) had either aortic or mitral atresia, and four (9.5%) had no valvular atresia. There was no statistically significant difference in postoperative mortality between the groups 1 and 2 (12/22 [54.5%] vs 7/12 [58.3%]; P=.56). The only significant risk factor for in-hospital mortality was a longer cardiopulmonary bypass time (P=.01) and, for intraoperative mortality, primary rather than delayed sternal closure (P=.004). Venous pCO2, the mean dead space fraction, and tissue oxygen extraction all tended to be higher among infants who died, but the difference was not statistically significant. Conclusions. Use of a right ventricle to pulmonary artery conduit did not improve postoperative survival. Both a long cardiopulmonary bypass time and primary sternal closure were associated with increased mortality (AU)

[Risk factors associated with arterial switch operation for transposition of the great arteries]. / Factores de riesgo de la corrección anatómica para la transposición de grandes arterias.

INTRODUCTION AND OBJECTIVES: The present study was undertaken to determine the risk factors for early mortality following an arterial switch operation. PATIENTS AND METHOD: From January 1994 through October 2003, 78 pediatric patients underwent surgical repair. Simple transposition was present in 48 patients (61.5%), 29 (37.2%) had an associated ventricular septal defect, and one had a Taussig-Bing anomaly. The risk factors analyzed were: the patient's age and weight at the time of the intervention, repair of a coexisting ventricular septal defect, coronary artery anatomical pattern, duration of cardiopulmonary bypass, duration of aortic cross-clamping, and duration of circulatory arrest. All factors were evaluated for strength of association with the duration of mechanical ventilation, the length of intensive care unit stay, and mortality. RESULTS: Overall, the early mortality rate was 9% (7/78). Some 14 patients (17.9%) underwent simultaneous repair of a ventricular septal defect. Patients with an intramural coronary artery (n=3, 3.8%) or a single coronary ostium (n=5, 6.4%) were the only ones who had a significant (P<.05) mortality risk, at 50% (4/8). Circulatory arrest was implemented in 53 (68%) patients. There were significant correlations between the duration of circulatory arrest and the ventilator support time (r=0.3, P<.05) and the duration of stay in the intensive care unit (r=0.3, P<.05). CONCLUSIONS: The risk of early death was increased when more complex coronary artery anatomical variants were present. As the period of circulatory arrest lengthened, the mechanical ventilation time and duration of intensive care unit stay increased.

Factores de riesgo de la corrección anatómica para la transposición de grandes arterias / Risk factors associated with arterial switch operation for transposition of the great arteries

Introducción y objetivos. Este estudio se realizó para determinar los factores de riesgo que pueden influir en la mortalidad precoz después de la corrección anatómica. Pacientes y método. Entre enero de 1994 y octubre de 2003 intervenimos a 78 pacientes; 48 (61,5%) eran transposiciones simples, 29 (37,2%) presentaban asociada una comunicación interventricular y 1 tenía una anomalía de Taussing-Bing. Se analizaron la edad y el peso en el momento de la intervención, el cierre o no de la comunicación interventricular, la anatomía coronaria y los tiempos de circulación extracorpórea, la anoxia miocárdica y la parada circulatoria. Evaluamos la relación entre estas variables con los tiempos de ventilación mecánica, la estancia en la unidad de cuidados intensivos pediátricos y la mortalidad. Resultados. De los 78 niños fallecieron 7 (9%). En 14 (17,9%) se cerró, además, una comunicación interventricular. Los que presentaron una arteria coronaria intramural (n = 3, 3,8%) o tenían un orificio coronario único (n = 5, 6,4%) fueron los que tuvieron una mayor mortalidad (4/8, 50%) (p < 0,05). En 53 niños (68%) se realizó parada circulatoria; el tiempo de parada se correlacionó de forma directa tanto con las horas de ventilación mecánica (r = 0,3; p < 0,05) como con los días de estancia (r = 0,3; p < 0,05). Conclusiones. Las variantes más complejas en la anatomía coronaria se asociaron con un mayor riesgo de muerte precoz. La duración de la parada circulatoria influyó en los tiempos de ventilación mecánica y en la estancia en cuidados intensivos

Introduction and objectives. The present study was undertaken to determine the risk factors for early mortality following an arterial switch operation. Patients and method. From January 1994 through October 2003, 78 pediatric patients underwent surgical repair. Simple transposition was present in 48 patients (61.5%), 29 (37.2%) had an associated ventricular septal defect, and one had a Taussig-Bing anomaly. The risk factors analyzed were: the patient's age and weight at the time of the intervention, repair of a coexisting ventricular septal defect, coronary artery anatomical pattern, duration of cardiopulmonary bypass, duration of aortic cross-clamping, and duration of circulatory arrest. All factors were evaluated for strength of association with the duration of mechanical ventilation, the length of intensive care unit stay, and mortality. Results. Overall, the early mortality rate was 9% (7/78). Some 14 patients (17.9%) underwent simultaneous repair of a ventricular septal defect. Patients with an intramural coronary artery (n=3, 3.8%) or a single coronary ostium (n=5, 6.4%) were the only ones who had a significant (P<.05) mortality risk, at 50% (4/8). Circulatory arrest was implemented in 53 (68%) patients. There were significant correlations between the duration of circulatory arrest and the ventilator support time (r=0.3, P<.05) and the duration of stay in the intensive care unit (r=0.3, P<.05). Conclusions. The risk of early death was increased when more complex coronary artery anatomical variants were present. As the period of circulatory arrest lengthened, the mechanical ventilation time and duration of intensive care unit stay increased