Ibuprofen treatment after the first days of life in preterm neonates with patent ductus arteriosus

Aim: Patent ductus arteriosus (PDA) is treated with ibuprofen and it is known that the clearance of ibuprofen increases with postnatal age. We aimed to study whether postnatal age-adjusted ibuprofen dosages improve the effectiveness of treatment compared to standard ibuprofen dosages after the first days of life. Methods: A historical cohort of 207 preterm neonates treated with standard ibuprofen dosages (Group A; 2011–2015) was compared to a prospective cohort of 66 preterm neonates treated with postnatal age-adjusted ibuprofen dosages (Group B; 2015–2016). Results: Both groups had comparable background characteristics. Treatment was started after median 6 (25–75th percentile: 4–11) and 5 (25–75th percentile: 4–11) days and effectiveness was 33.2 and 44.7% (p =.17) in groups A and B, respectively. No hemodynamically significant PDA was found in 23/49 (46.9%) of the patients born before 28 weeks after adjusted ibuprofen dosages compared to 48/162 (29.6%) after standard ibuprofen dosages (p =.04). There were significantly more reversible side effects with the postnatal age-adjusted ibuprofen dosages (p =.04). Conclusions: There seems to be a trend to higher effectiveness with the adjusted ibuprofen dosages in preterm neonates before 28 weeks, but it is associated with more reversible side effects

Limited effects of intravenous paracetamol on patent ductus arteriosus in very low birth weight infants with contraindications for ibuprofen or after ibuprofen failure

Finding the optimal pharmacological treatment of a patent ductus arteriosus (PDA) in preterm neonates remains challenging. There is a growing interest in paracetamol as a new drug for PDA closure. In this prospective observational cohort study, we evaluated the effectiveness of intravenous paracetamol in closing a PDA in very low birth weight infants with a hemodynamically significant PDA who either did not respond to ibuprofen or had a contraindication for ibuprofen. They received high-dose paracetamol therapy (15 mg/kg/6 h intravenous) for 3–7 days. Cardiac ultrasounds were performed before and 3 and 7 days after treatment. Thirty-three patients were included with a median gestational age of 251/7 weeks (IQR 1.66), a median birth weight of 750 g (IQR 327), and a median postnatal age of 14 days (IQR 12). Paracetamol was ineffective in 27/33 patients (82 %). Even more, after previous exposure to ibuprofen, this was even 100 %. Conclusion: In this study, paracetamol after ibuprofen treatment failure was not effective for PDA closure in VLBW infants. From the findings of this study, paracetamol treatment for PDA closure cannot be recommended for infants with a postnatal age >2 weeks. Earlier treatment with paracetamol for PDA might be more effective.What is known:• The ductus arteriosus fails to close after birth in 30 to 60 % of prematurely born neonates and is a significant cause of morbidity and mortality in these infants.• Paracetamol gained importance as an alternative drug in PDA closure.What is new:• Paracetamol for PDA closure after ibuprofen treatment failure was not effective in VLBW infants.• Effect of paracetamol on PDA closure was observed when given as primary treatment

Enantiomer specific pharmacokinetics of ibuprofen in preterm neonates with patent ductus arteriosus

Aims: Racemic ibuprofen is widely used for the treatment of preterm neonates with patent ductus arteriosus. Currently used bodyweight-based dosing guidelines are based on total ibuprofen, while only the S-enantiomer of ibuprofen is pharmacologically active. We aimed to optimize ibuprofen dosing for preterm neonates of different ages based on an enantiomer-specific population pharmacokinetic model. Methods: We prospectively collected 210 plasma samples of 67 preterm neonates treated with ibuprofen for patent ductus arteriosus (median gestational age [GA] 26 [range 24–30] weeks, median body weight 0.83 [0.45–1.59] kg, median postnatal age [PNA] 3 [1–12] days), and developed a population pharmacokinetic model for S- and R-ibuprofen. Results: We found that S-ibuprofen clearance (CLS, 3.98 mL/h [relative standard error {RSE} 8%]) increases with PNA and GA, with exponents of 2.25 (RSE 6%) and 5.81 (RSE 15%), respectively. Additionally, a 3.11-fold higher CLS was estimated for preterm neonates born small for GA (RSE 34%). Clearance of R-ibuprofen was found to be high compared to CLS (18 mL/h [RSE 24%]), resulting in a low contribution of R-ibuprofen to total ibuprofen exposure. Current body weight was identified as covariate on both volume of distribution of S-ibuprofen and R-ibuprofen. Conclusion: S-ibuprofen clearance shows important maturation, especially with PNA, resulting in an up to 3-fold increase in CLS during a 3-day treatment regimen. This rapid increase in clearance needs to be incorporated in dosing guidelines by adjusting the dose for every day after birth to achieve equal ibuprofen exposure