Abstract The objective of this study was to evaluate the agronomic performance of 11 grass accessions associated with the legume Lotus uliginosus Schkuhr, at two cutting ages, in the high Andean tropic of Colombia. The trial was conducted at the Marengo Animal Husbandry Center, of the National University of Colombia, in the Mosquera municipality, Cundinamarca, Colombia. Eleven grass accessions associated with the legume and a pure control (Cenchrus clandestinus Hochst. ex Chiov), were evaluated, using a randomized block design with split-strip arrangement and three repetitions. The biomass production was measured when cutting at 45 and 70 days in the rainy and dry seasons. In general, L. uliginosus as well as the associated grasses showed good growth in the establishment stage. The total aerial biomass production was higher in the rainy season and with the 70-day frequency, especially in the associations with Festuca rubra, Festuca arundinacea, Bromus catharticus, Anthoxantum odoratum and Holcus lanatus. The grasses F. rubra, F. arundinacea, B. catharticus and C. clandestinus (naturalized) stood out for their high aerial biomass production, with a higher production than that of the pure control. It is concluded that the associations with the best performance were F. arundinacea and C. clandestinus, the naturalized as well as the introduced one, which stood out for their higher resistance to pests and diseases during the establishment stage, showing the potential of this type of system in the high Colombian Andean tropic.

Resumen El objetivo del presente estudio fue evaluar el comportamiento agronómico de 11 accesiones de gramíneas asociadas con la leguminosa Lotus uliginosus Schkuhr, a dos edades de corte, en el trópico alto andino de Colombia. El ensayo se realizó en el Centro Agropecuario Marengo, de la Universidad Nacional de Colombia, en el municipio de Mosquera, Cundinamarca, Colombia. Se evaluaron 11 accesiones de gramíneas asociadas con la leguminosa y un control puro (Cenchrus clandestinus Hochst. ex Chiov), empleando un diseño de bloques al azar con arreglo de franjas divididas con 3 repeticiones. Se midió la producción de biomasa al realizar cortes a los 45 y 70 días en el período lluvioso y poco lluvioso. En general, tanto L. uliginosus como las gramíneas asociadas presentaron buen desarrollo en la fase de establecimiento. La producción de biomasa aérea total fue mayor en el período lluvioso y con la frecuencia de 70 días, destacándose las asociaciones con Festuca rubra, Festuca arundinacea, Bromus catharticus, Anthoxantum odoratum y Holcus lanatus. Sobresalieron por su alta producción de biomasa aérea las gramíneas F. rubra, F. arundinacea, B. catharticus y C. clandestinus (naturalizado), con una producción superior a la del control puro. Se concluye que las asociaciones que tuvieron mejor comportamiento fueron F. arundinacea y C. clandestinus, tanto el naturalizado como el introducido, las cuales se destacaron por su mayor resistencia a plagas y enfermedades durante la fase de establecimiento, lo que mostró el potencial de este tipo de sistema en el trópico alto andino colombiano.

El experimento se desarrolló en un oxisol del Piedemonte Llanero colombiano. Durante el primer año de establecimiento y con un diseño experimental de bloques completos al azar en arreglo de parcelas subdivididas, se evaluaron los pastos B. decumbens cv. Amargo y B. brizantha cv. Toledo, bajo tres frecuencias de defoliación (14, 28 y 42 días) y dos intensidades de defoliación (alta y baja). El área foliar y la biomasa disponible total no presentaron diferencias significativas en los dos pastos, obteniéndose a un promedio de 2,5 y 2.036 kg MSxha-1 respectivamente. La biomasa residual total fue superior en el pasto Toledo porque con 3.284 kg MSxha-1, superó ampliamente al pasto Amargo cuya acumulación de biomasa residual fue de 1.944 kg MSxha-1. La intensidad de defoliación baja, favoreció la producción de forraje disponible y residual de los pastos evaluados. Se presentó una disponibilidad de 2.056 kg MSxha-1 en la intensidad baja y 1.760 kg MSx ha-1 en la intensidad alta. El forraje residual compuesto en su mayoría por tallos fue de 2.860 kg MS x ha-1 en la intensidad baja y de 2.216 kg MSxha-1 en la intensidad alta. Cuando la defoliación se realizó a los 14 días, los pastos presentaron buen contenido de proteína (12,9%) pero la disponibilidad de biomasa fue baja ( 714 kg MSxha-1), en tanto, a los 42 días se alcanzó a 2.760 kg MSxha-1 con una proteína de 9,8%. Los nutrientes de reserva en los dos pastos en su mayoría estuvieron conformados por azucares solubles, los cuales se acumularon en más cantidad en los tallos y el contenido más elevado se encontró a los 28 días de rebrote.

In an oxisol of colombian plain piedmont was made the experiment. During the first year of establishment and with an experimental design of complete blocks at random in split-plot arrangement, the grasses B. decumbens cv. Amargo and B. brizantha cv. Toledo were evaluated under three defoliation frequencies (14, 28 and 42 days) and two defoliation intensities. The leaf area and total available biomass didn't present significant differences in the two grasses, being obtained to an average of 2,5 and 2.036 kg MSxha-1 respectively. Total residual biomass was greater in Toledo grass because with 3.284 kg MSx ha-1, it overcame the pasto Amargo whose accumulation of residual biomass was of 1.944 kg MSxha-1. The intensity of low defoliation favored the production of available and residual forage of evaluated grasses. An available forage of 2.056 kg MSxha-1 was presented in the low intensity and 1.760 kg MSxha- 1 in the high intensity. The compound residual forage in its majority for stems was of 2.860 kg MSxha- 1 in the low intensity and of 2.216 kg MSxha- 1 in the high intensity. When defoliation was carried out to the 14 days, grasses presented good protein content (12,9%) but the availability of biomass was low ( 714 kg MSxha-1), whereas, to 42 days it reaches to 2.760 kg MSxha-1 with a protein of 9,8%. The reserve nutrients in the two grasses were conformed by soluble sugars in their majority, which were accumulated in more quantity in stems and the highest content was found to 28 days of regrow.

OBJETIVO: Comparar pacientes submetidos à ultrafiltração convencional (UFC), sem e com modificação técnica que permite aproveitamento do sangue residual do circuito de tubos e do oxigenador. MÉTODO: No período de março de 2002 a janeiro de 2005, 301 pacientes submetidos à correção de cardiopatias congênitas com circulação extracorpórea (CEC) foram analisados, retrospectivamente, e divididos em dois grupos: A - constituído de 130 pacientes submetidos à UFC clássica e grupo B - constituído de 171 pacientes submetidos à UFC com modificação técnica para aproveitamento do sangue residual. Foram comparadas variáveis demográficas, diagnóstico, tratamento cirúrgico, dados do período intra-operatório e pós- operatório, necessidade e volume de transfusões, exames laboratoriais e permanência hospitalar. RESULTADOS: Não houve diferença no valor inicial de hematócrito antes da CEC (p = 0,06), mas no grupo B, os valores após a ultrafiltração foram maiores (p < 0,0001). O grupo B foi mais transfundido nas primeiras 48 horas do pós-operatório (p < 0,0001). Não houve diferença no tempo de ventilação mecânica (p = 0,34), mas o tempo de uso de drogas vasoativas (p < 0,0001), tempo de uso de antibióticos (p = 0,0006), tempo de internação na unidade de terapia intensiva (p < 0,0001) e o tempo total de internação no pós-operatório (p < 0,0001) foram maiores no grupo B. CONCLUSÕES: A UFC com a modificação técnica não apresentou resultados superiores aos da UFC clássica, pois, apesar de elevar o hematócrito após a circulação extracorpórea, proporcionou maior sangramento no pós-operatório com maior necessidade de transfusão de hemoderivados e prolongamento do tempo de permanência hospitalar.

OBJECTIVE: To compare patients submitted to the conventional ultrafiltration (CUF) with and without a technical modification that allows use of residual blood from the circuit tubes and oxygenator. METHOD: From March 2002 to January 2005, 301 patients undergoing to congenital heart defects surgery with cardiopulmonary bypass (CPB) were retrospectively analyzed and divided in two groups: Group A - 130 submitted to CUF and Group B, 171 patients submitted to CUF with a technical modification that uses residual blood. Demographic data, diagnosis, surgical treatment, intra-operative and postoperative data, the need and amount of blood transfusions, laboratorial results and length of hospital stay were compared between the groups. RESULTS: There was no differences in the initial hematocrit before CPB (p = 0.06), but in the Group B, the values after ultrafiltration were higher (p <0.0001). Group B patients received more transfusions in the first 48 hours of the postoperative period (p <0.0001). There was no signicant difference in the time of mechanical ventilation (p = 0.34), but the inotropic support (p <0.0001), antibiotic therapy (p = 0.0006), length of stay in the intensive care unit (p <0.0001) and length of hospital stay (p <0.0001) were greater for Group B. CONCLUSIONS: CUF with the technical modification was not better than conventional CUF, because in spite of elevating the hematocrit after the CBP, it caused greater postoperative bleeding with a greater need of blood transfusions and longer hospitalar stays.

OBJETIVO: Comparar os pacientes onde a operação foi realizada com circulação extracorpórea (CEC) àqueles sem CEC, analisando suas características e verificando se houve ou não superioridade de alguma das técnicas empregadas. MÉTODO: Entre janeiro de 2002 e janeiro de 2004, 16 pacientes foram submetidos à operação de Glenn bidirecional (GB), todos com defeitos cardíacos complexos. Quatorze eram do sexo feminino, com idade mediana de 19 meses. Os pacientes foram divididos em dois grupos: A (GB com CEC) e B (GB sem CEC), sendo sete do grupo A e nove do grupo B. Foram analisadas comparativamente as variáveis: sexo, idade, pressão arterial pulmonar média (PAPM), operação realizada, tempo de CEC, pinçamento da aorta, derivação venoatrial, operações prévias, internação na unidade de terapia intensiva (UTI), hospitalização e complicações imediatas. RESULTADOS: A mediana da PAPM foi 13 mmHg. No grupo A, o tempo foi de CEC 91 ± 47 minutos (57-195 minutos) e o de isquemia miocárdica 25 ± 33 minutos (0-80 minutos). Destes, quatro necessitaram de procedimento intracardíaco ou ampliação de ramos pulmonares e três, auxílio da CEC como suporte ventilatório. No grupo B o tempo de desvio venoatrial foi de 21 ± 10 minutos (0-39 minutos). O tempo para extubação 9 ± 13 horas, mediana 3 horas (1-43 horas). A permanência UTI foi de 8 ± 12 dias, mediana 5 dias (1-50 dias). O período médio de internação hospitalar foi de 12 ± 12 dias, mediana 7 dias (0-50 dias). Cinco pacientes haviam sido submetidos à operação prévia. Dois (12,5%) faleceram, sendo um em cada grupo. Não houve complicações neurológicas, derrame pleural ou pericárdico. Todas as variáveis estudadas entre os grupos não apresentaram diferença estatística significativa. CONCLUSÃO: Apesar da amostra relativamente pequena, o presente estudo sugere que a operação de GB pode ser realizada com ou sem CEC com resultados semelhantes no que se refere à morbidade e mortalidade. Assim sendo, a operação sem CEC pode ser empregada com segurança quando os achados anatômicos forem apropriados e não houver hipóxia grave.

OBJECTIVE: To compare patients who underwent the Bidirectional Glenn Operation with and without cardiopulmonary bypass (CPB), analyzing the characteristics and confirming if there is superiority of either of the employed techniques. METHOD: Between January 2002 and January 2004, 16 patients with complex heart defects were submitted to this operative technique. The mean age of the patients was 19 months and 14 were female. The patients were divided into two groups: Group A with seven patients (using CPB) and group B with 9 patients (without the use of CPB). Gender, age, mean pulmonary artery pressure (MPAP), CPB time, aortic clamping time, venoatrial shunt, previous operations, time in intensive care unit (ICU), total hospitalization time and immediate complications were all compared between the two groups. RESULTS: The median MPAP was 13 mmHg. In group A the CPB time was 91 ± 47 minutes (57-195 minutes), myocardial ischemia was 25 ± 33 minutes (0-80 minutes). Of these four patients required intracardiac procedures or enlargement of the pulmonary branches and in three, CPB assistance as ventilatory support was needed. In group B the venoatrial shunt was 21 ± 10 minutes (0-39 minutes). The time to extubation was 9 ± 13 hours with a median of 3 hours (1-43 hours). The ICU stay was 8 ± 12 days with a median of 5 days (1-50 days). Hospitalization was 12 ± 12 days with a median of 7 days (0-50 days). Five patients had been submitted to surgeries previously. Two, one patient from each group, died (12.5%). No neurological complications, pleural or pericardial effusions were observed. No significant differences were evidenced between the two groups in respect to all the variables studied. CONCLUSION: In spite of the relatively small cohort, this study suggests that the bidirectional Glenn operation can be performed with or without CPB giving similar results in respect to morbidity and mortality. Thus, the operation without CPB can be safely employed when the anatomic findings are appropriate and there is no severe hypoxia.