Nasal colonization among premature infants treated with nasal continuous positive airway pressure.

We examined the relationship between the use of nasal continuous positive airway pressure (CPAP) and nasal colonization among low-birth-weight (LBW) infants. We prospectively cultured the nares of LBW infants on admission and weekly until hospital discharge. The modality of respiratory support during each culture was recorded. Bivariate and multivariate analyses were conducted to test the relationship between CPAP and nasal colonization. Analyses were repeated after stratifying infants into three birth-weight categories: 1500 to 2499 g, 1000 to 1499 g, and < 1000 g. In total, 766 nasal cultures were obtained from 167 infants. Nasal colonization with gram-negative bacilli was increased with the use of CPAP in all birth-weight categories ( P < 0.05) and with vaginal delivery in infants weighing < 1000 g and 1500 to 2499 g ( P = 0.04 and P = 0.02, respectively). Nasal colonization with any potential pathogen increased with the use of CPAP in all birth-weight categories ( P < 0.001), with the presence of chorioamnionitis in infants < 1000 g ( P = 0.055) and at younger gestational age in infants 1000 to 1499 g ( P = 0.0026). Caucasian infants 1500 to 2499 g had less colonization than infants of other races ( P = 0.01). Nasal CPAP is associated with increased colonization with gram-negative bacilli.