Nephrotoxic medication exposure in very low birth weight infants

Objective: To quantify exposure to potentially nephrotoxic medications among very low birth weight (VLBW) infants and determine the relationship of nephrotoxic medication exposure to acute kidney injury (AKI) in this vulnerable population. Methods: We reviewed 107 VLBW infants who survived to discharge from April 2011 to March 2012 and measured exposure to the following nephrotoxic medications: acyclovir, amikacin, amphotericin B, gentamicin, ibuprofen, indomethacin, iohexol, tobramycin and vancomycin. Acute kidney injury was determined by the KDIGO guidelines. Results: Exposure to >= 1 nephrotoxic medication occurred in 87% of infants. The most common exposures were gentamicin (86%), indomethacin (43%) and vancomycin (25%). There was an inverse linear relationship between birth weight and nephrotoxic medications received per day (R-2 = 0.169, p<0.001). Infants with AKI received more nephrotoxic medications per day than those who did not (0.24 versus 0.15; p = 0.003). Conclusions: VLBW infants are frequently exposed to nephrotoxic medications, receiving approximately two weeks of nephrotoxic medications before discharge or 1 for every 6 d of hospitalization. The greatest exposure occurred among the smallest, most immature infants and those who experienced AKI.