Extracorporeal perfusion of xenospleen was used in the management of 11 critically ill children with acute multisegmental pneumonia. The first 24 h were characterized by progressive mounting in blood O2 saturation, optimization of hemodynamics and immune status, decrease of toxemia. On days 4-7 after perfusion stabilization of clinical, laboratory and functional indexes was observed. Radiological findings of pulmonary infiltration disappeared 10-14 days after sorption and all the patients were transferred to a somatic unit.