[Serum digoxin in children treated with beta methyl digoxin]. / Concentraciones séricas de digoxina en niños tratados con beta metil digoxina.

Concentrations of serum digoxin were measured by the polarized immunofluorescence Abbot TDx11 method in 59 samples from 53 children under treatment with mean beta methyl digoxin doses of 8.9 +/- 2.0 micrograms.kg.day. The therapeutic range for serum digoxin concentration was estimated to be 0.9 to 2.25 ng/ml. Simultaneous Na, K and creatine serum concentrations were measured. In 36 samples mean serum digoxin level was 1.52 +/- 0.45 ng/ml -within therapeutic range- and in only one of these cases clinical evidence of toxicity was apparent. In 15 samples digoxin level was above the therapeutic range and 11 patients of this group (73%) showed clinical signs of toxicity, consisting in arrythmias (six cases: supraventricular in 5 patients, ventricular in one child) and gastrointestinal symptoms (eight patients). Six patients with digoxin levels over therapeutic range and signs of digitalis toxicity had coincidental acute renal failure, which in 4 cases was subclinical--in 2 of these late it was pre-renal- and, in spite of this, all were inadvertently given the usual dosage of beta methyl digoxin. Almost invariably there was clinical evidence of toxicity when digoxin serum levels were above 2.4 ng/ml, so established maximal therapeutic level at 2.25 ng/ml seems adequate. Signs of digitalis toxicity must be looked on systematically in children treated with such drugs. In the critically ill or in children with acute renal failure it is necessary to monitor serum digoxin concentration. Among the clinical signs of toxicity, gastrointestinal symptoms are more frequent in children. An oral dose from 7 to 10 micrograms.kg.day of beta methyl digoxin in recommended.

Resultados de la reparación quirúrgica del canal auriculo-ventricular completo / Repair of atrioventricular canal malformation

En Mayo de 1981 a Junio de 1989, se han reparado con circulación extracorpórea, 48 pacientes portadores de canal auriculo-ventricular completo sin otras lesiones mayores asociadas. La mortalidad hospitalaria es de un 8,3% y la global de un 20,8%. No se han presentado casos de bloqueo AV permanente y sólo en 1 caso se realizó reoperación para recambio valvular. En los últimos tres años (24 pacientes) se ha operado más precozmente (promedio de edad de 16,6 meses baja a 9,5 meses), lo que junto a una mejor comprensión de la patología y a avances en las técnicas quirúrgicas y en el cuidado postoperatorio, han permitido alcanzar una mortalidad hospitalaria de un 4,2%