Randomised trial of erythromycin on the development of chronic lung disease in preterm infants. Endotracheal intubation and its relationship to bacterial colonization and systemic infection of newborn infants.
To determine if erythromycin given from birth reduces the inflammatory response and the incidence and severity of chronic lung disease.
                Seventy five infants less than 30 weeks of gestation and ventilated from birth for lung disease were randomly assigned to receive erythromycin intravenously for 7 days or to no treatment. Ureaplasma urealyticum was detected in tracheal secretions by culture and polymerase chain reaction. Differential cell counts were obtained from bronchoalveolar lavage fluid collected daily for 5 days and concentrations of the cytokines interleukins IL-1 beta and IL-8, and tumour necrosis factor alpha (TNF-alpha) were measured. Chronic lung disease (CLD) was defined as oxygen dependency at 36 weeks of gestation.
                Nine infants (13%) were positive for U urealyticum. The inflammatory cytokines in the lungs increased over the first 5 days of life in all babies, but no association was found between their concentrations and the development of CLD. Those treated with erythromycin showed no significant differences from the non-treated group in the differential cell counts or concentrations of the cytokines. The two groups had a similar incidence of CLD. Babies infected with U urealyticum did not have a more pronounced cytokine response than those without infection. Chorioamnionitis was associated with significantly higher concentrations of IL-1 beta and IL-8 on admission: these babies had less severe acute lung disease and developed significantly less CLD.
                U urealyticum in the trachea was not associated with an increased inflammatory response in preterm infants. Erythromycin did not reduce the incidence or severity of CLD. The role of antibiotics in preventing respiratory tract bacterial colonization and systemic infection after orotracheal intubation was prospectively studied in 54 newborn infants. Respiratory tract colonization was assessed from nasopharyngeal and tracheal aspirate cultures obtained at intubation and daily thereafter, while systemic infection was monitored by blood, cerebrospinal fluid, and suprapubic urine cultures performed initially and every three days thereafter while intubated. Colonization and systemic cultures were also obtained at extubation or death. The study group, provided with antibiotics at intubation, and the control group were similar in birthweight and gestational age, as well as race, sex, hospital or origin, and indication for intubation. Colonization at intubation was five times more common in infants intubated 12 or more hours after birth than in infants intubated earlier. Subsequent colonization was twice as frequent in infants intubated longer than 72 hours as well as in those requiring two or more reintubations. Systemic infection occurred only in those infants who were initially or subsequently colonized and was three times more frequent in the control group than in the study group.
There is insufficient evidence from randomised trials to support or refute the use of prophylactic antibiotics when starting mechanical ventilation in newborn infants, or to support or refute continuing antibiotics once initial cultures have ruled out infection in mechanically ventilated newborn infants.