CON ESTETOSCOPIO

El grupo de Alabama comparte su experiencia en estos tres casos de pacientes lactantes con cardiopatía congénita (conexión venosa pulmonar anómala supracardíaca en e postoperatorio inmediato, Coartación aórtica con edema agudo pulmonar y hemorragia pulmonar como cuadro de inicio y tetralogía de fallot post corrección con parche trans anular en el postoperatorio inmediato) en quienes se presenta síndrome de dificultad respiratoria agudo con daño pulmonar agudo, atribuible al uso de circulación extracorpórea y a la hemorragia pulmonar, y que con el uso de surfactane exógeno a dosis de 3 cc/kg por vía endotraqueal, se logra mejoría en índices respiratorios y de gasto cardíaco, se evita el uso de ECMO y se logra la extubación electiva en días subsecuentes.

Los autores contrastan su reporte con dos experiencias previas publicadas en casos similares donde no se registra mejoría y lo explican por el tipo diferente de surfactante exógeno empleado. Publicado en Congenital Heart Disease del 2010, y proveniente de un grupo prestigiado, hace énfasis en la necesidad de estudios prospectivos para confirmar su utilidad, tanto de manera preventiva a la circulación extracorpórea como en los casos con dificultad respiratoria establecida donde la disfunción del surfactante es parte de la fisiopatología de esta entidad de ,morbi mortalidad importante.

Buscando más información, encontré este ensayo clínico controlado del cual reproduzco lo publicado en el BMJ evidence Update:

Willson DF, Thomas NJ, Markovitz BP, et al. Effect of exogenous surfactant (calfactant) in pediatric acute lung injury: a randomized controlled trial. JAMA. 2005 Jan 26;293(4):470-6. (Original) PMID: 15671432

CONTEXT: Despite evidence that patients with acute lung injury (ALI) have pulmonary surfactant dysfunction, trials of several surfactant preparations to treat adults with ALI have not been successful. Preliminary studies in children with ALI have shown that instillation of a natural lung surfactant (calfactant) containing high levels of surfactant-specific protein B may be beneficial.
OBJECTIVE: To determine if endotracheal instillation of calfactant in infants, children, and adolescents with ALI would shorten the course of respiratory failure.
DESIGN, SETTING AND PATIENTS: A multicenter, randomized, blinded trial of calfactant compared with placebo in 153 infants, children, and adolescents with respiratory failure from ALI conducted from July 2000 to July 2003. Twenty-one tertiary care pediatric intensive care units participated. Entry criteria included age 1 week to 21 years, enrollment within 48 hours of endotracheal intubation, radiological evidence of bilateral lung disease, and an oxygenation index higher than 7. Premature infants and children with preexisting lung, cardiac, or central nervous system disease were excluded.
INTERVENTIONS: Treatment with intratracheal instillation of 2 doses of 80 mL/m2 calfactant or an equal volume of air placebo administered 12 hours apart.
MAIN OUTCOME MEASURES: Ventilator-free days and mortality; secondary outcome measures were hospital course, adverse events, and failure of conventional mechanical ventilation.
RESULTS: The calfactant group experienced an acute mean (SD) decrease in oxygenation index from 20 (12.9) to 13.9 (9.6) after 12 hours compared with the placebo group`s decrease from 20.5 (14.7) to 15.1 (9.0) (P = .01). Mortality was significantly greater in the placebo group compared with the calfactant group (27/75 vs 15/77; odds ratio, 2.32; 95% confidence interval, 1.15-4.85), although ventilator-free days were not different. More patients in the placebo group did not respond to conventional mechanical ventilation. There were no differences in long-term complications.
CONCLUSIONS: Calfactant acutely improved oxygenation and significantly decreased mortality in infants, children, and adolescents with ALI although no significant decrease in the course of respiratory failure measured by duration of ventilator therapy, intensive care unit, or hospital stay was observed.

José Antonio Quibreera Matienzo

Cardiología Pediátrica