iPAPP: study protocol for a multicentre randomised controlled trial comparing safety and efficacy of intravenous paracetamol and indomethacin for the treatment of patent ductus arteriosus in preterm infants.

INTRODUCTION: Patent ductus arteriosus (PDA) causes severe morbidity in premature infants. Although the use of indomethacin is the standard therapy for PDA, it is sometimes not applicable because of its adverse effects, such as renal and platelet dysfunctions. Paracetamol has emerged as an alternative to indomethacin owing to its excellent safety profile in infants. Of the recently reported case series and clinical trials on the use of paracetamol for PDA, there are few reports in Japan on paracetamol use in preterm infants. Furthermore, indications for the use of paracetamol for PDA have not been approved for use in PDA. While the safety of intravenous paracetamol therapy in case series of preterm infants treated for haemodynamically significant PDA (hsPDA) has been reported, studies which were conducted to compare paracetamol to indomethacin are limited. We, therefore, intend to investigate the hypothesis that intravenous administration of paracetamol has superior safety over indomethacin. METHODS AND ANALYSIS: Multicentre open-label randomised controlled trial for intravenous administration of paracetamol for PDA in preterm infants. The inclusion criteria are (1) hsPDA, (2) gestational age from 24 to 34 weeks and birth weight (BW) from 500 to 2000 g, (3) enrolment between 24 hours and 7 days from birth and (4) obtaining parental consent. The primary outcome is renal dysfunction within 48 hours from the last dose of the study drug. Enrolled patients fulfilling all the inclusion criteria are randomly allocated to either intravenous paracetamol or intravenous indomethacin. This trial requires 110 patients. ETHICS AND DISSEMINATION: The clinical trial would follow Japan's Clinical Trials Act. The trial protocol was approved by the Clinical Research Review Board of Saitama Medical University (approval number: 222001). A written informed consent would be obtained from one of the parents. The results are expected to be published in a scientific journal. TRIAL REGISTRATION NUMBER: jRCTs031220386. PROTOCOL VERSION: 31 March 2022, version 1.0.

Therapeutic response of iNO in preterm infants with hypoxemic respiratory failure.

BACKGROUND: Inhaled nitric oxide (iNO) has been used as a rescue treatment for preterm infants with hypoxemic respiratory failure (HRF). However, its effectiveness remains debatable. Thus, in this study, we aimed to examine the impact of iNO therapy on HRF in extremely preterm infants. METHODS: A retrospective observational study was performed. Extremely preterm infants admitted to our neonatal intensive care unit who received iNO therapy later in their postnatal life were included. The oxygen saturation index (OSI) was used as an index of the severity of respiratory failure. RESULTS: In total, 30 extremely preterm infants were included in this study. Oxygenation was enhanced after the administration of iNO in infants with HRF. The OSI decreased by more than 20% in 12 patients (40%, positive responder) and did not decrease in 17 patients (57%, negative responder) within the first 6 h of treatment. The iNO initiation day was the significant independent factor associated with a positive response to iNO therapy in extremely preterm infants with HRF. CONCLUSIONS: iNO therapy was effective in enhancing oxygenation in extremely preterm infants with HRF. Earlier use of iNO was the significant factor associated with a positive therapeutic response to iNO, implying that iNO may be more effective in pulmonary vessels which are less damaged by shorter-term mechanical ventilation.