Background Paracetamol (both IV and PO) has been shown to be effective at closing haemo-dynamically significant Patent Ductus Arteriosus (PDA) in preterm infants. Currently, Ibuprofen is the only licensed medical treatment for PDA in neonates but Paracetamol has been suggested as a second line agent where Ibuprofen therapy has failed or is contraindicated. The aim of this project was to review the use of Paracetamol for the medical management of PDA in a tertiary neonatal unit in London. Patients received IV paracetamol in accordance with the West of Scotland guideline.

Objectives

1. To determine the number of infants treated with intravenous paracetamol for closure of PDA over a 2 year period and determine indication for paracetamol treatment rather than Ibuprofen

2. To determine if any infants suffered adverse effects or needed dose adjustment due to high paracetamol levels. Levels were measured before the 3rd dose of treatment

3. To determine the number of infants with successful closure of PDA following treatment with intravenous paracetamol

Methods A retrospective analysis was carried out using the online national neonatal database (BADGER). Infants were selected using the following search criteria

• Born between 1/3/2018 and 31/3/2020 and admitted to NICU

• Diagnosis of PDA confirmed on echo

• Treatment with at least one course of Paracetamol for medical management of PDA

Results 23 babies met the inclusion criteria. Male to female ratio was 11:12, gestational age range was 23+1 – 29+2 weeks (median 24+6) and birth weight 430 g – 1514 g (median 728 g). The main reason for medical treatment was ventilator dependence (22/23).

14/23 (61%) were treated with Paracetamol first line, due to contraindications to Ibuprofen

9/23 (39%) received Paracetamol as a second line treatment, following failed treatment with Ibuprofen

No adverse effects were reported, and no babies required dose adjustment due to high Paracetamol levels, all levels were below the toxic threshold (25 mg/L)

Successful closure of PDA was seen in 18/23 (83%) patients after the following treatment regimens with Paracetamol:

Of the remaining 5 patients, outcomes were as follows:

Conclusions Paracetamol appears to be a safe and effective medical treatment for haemo-dynamically significant PDA in preterm neonates who either have contra-indications to Ibuprofen or where Ibuprofen therapy has failed. The risk of toxicity was low (0% in this study) and the closure rate of PDA following treatment was high (83%). Further studies are needed to determine clinical effectiveness in larger sample sizes and to agree a consensus on how many courses of medical management are appropriate before referring for surgical ligation.