PULMONARY INFLAMMATORY CELLS IN VENTILATED PRETERM INFANTS - EFFECT OF SURFACTANT TREATMENT

The aim of this study was to determine the effect of surfactant treatm ent on the number and distribution of inflammatory cells in bronchoalv eolar lavage fluid (BALF) from mechanically ventilated preterm infants over the first week of life in relation to the subsequent development of chronic lung disease (CLD). The study included 25 babies who recei ved surfactant on clinical grounds and 29 babies of similar severity w ho did not. BALF was collected on days 1, 3, 5, and 7 after birth. Cel l counts were performed and differentials were calculated on 300 cells . CLD was equally common in both treatment groups. Of the 54 infants, 29 (53%) who developed CLD had a higher incidence of patent ductus art eriosus and air leak and needed a higher concentration of inspired oxy gen on the fifth and seventh days of life. Babies who developed CLD ha d more polymorphonuclear leucocytes and fewer macrophages on days 5 an d 7 than those who recovered. Surfactant treatment was associated with a higher total white cell count on day 3. Between days 3 and 7, macro phage numbers were higher in surfactant treated babies, whatever the p ulmonary outcome. This data suggests that CLD was associated with pers istence of high numbers of polymorphonuclear leucocytes in BALF at the end of the first week. Surfactant treatment caused a persistent incre ase in macrophage numbers. The association between persistent neutroph ilia and CLD was unaffected by surfactant treatment.