Tamara van Donge

Ibuprofen-related maturational adverse events in ELBW neonates 157 8 Table 2: Serum creatinine concentrations (mg/dL) for different gestational ages, exposed to ibuprofen treatment or without ibuprofen treatment. Separated for three treatment periods, starting at day 1, day 15 and day 29 of postnatal life and lasted for three days. Creatinine concentration (mg/dL) Period 1 (days 1 - 3) Period 2 (days 15 - 17) Period 3 (days 29-31) Before After Before After Before After Gestational age 24 weeks Ibuprofen 0.383 0.906 0.500 0.472 0.375 0.371 No ibuprofen 0.383 0.876 0.500 0.462 0.375 0.365 Gestational age 27 weeks Ibuprofen 0.462 0.857 0.439 0.419 0.345 0.344 No ibuprofen 0.462 0.830 0.439 0.411 0.345 0.339 Gestational age 29 weeks Ibuprofen 0.518 0.832 0.408 0.391 0.334 0.333 No ibuprofen 0.518 0.807 0.408 0.384 0.334 0.328 Gestational age 32 weeks Ibuprofen 0.607 0.795 0.374 0.360 0.321 0.322 No ibuprofen 0.607 0.772 0.374 0.355 0.321 0.318 Figure 2 illustrates the increasing clearance capacities during the postnatal period for ELBW neonates, depending on gestational age. Creatinine clearance is reduced when the neonate is exposed to ibuprofen, but this decrease is proportionally much more relevant in the first week of postnatal life. The reduction in creatinine clearance is assumed to be absolute (-0.0094 mL/min), indicating no difference between GA and postnatal age. Of note, the reduction of creatinine clearance due to ibuprofen treatment is therefore proportionally higher in the early days after birth (-5%) as compared to e.g. week 5 after birth (approximately -2%).