A medical instrument and method is provided for defoaming or preventing formation of foam in blood during extracorporeal blood circulation. The method comprises durably coating hydrophobic blood-contact surfaces with a nontoxic, biocompatible surface-active defoaming agent.

Um instrumento e um método médicos são fornecidos para o defoaming ou formação impedir da espuma no sangue durante a circulação extracorporal do sangue. O método compreende duràvelmente revestir hydrophobic sangue-contata superfícies com um agente surface-active nontoxic, biocompatible do defoaming.