Patent ductus arteriosus is associated with reduced life expectancy. Furthermore, mortality remains high despite advances in the common comorbidities management including bronchopulmonary dysplasia, necrotising enterocolitis, pulmonary hypertension and intraventricular haemorrhage.Reference Noori, McCoy and Friedlich ¹ It is widely accepted that the aforementioned are related to a “diastolic steal” due to the ductʼs left-to-right shunt.

In healthy babies, almost 100% of patent ductus arteriosus close spontaneously by day 4; however, just 20% do so in low birth weight or premature babies, in whom closure is expected within 2 years.Reference Reller, Rice and McDonald ² The question of whether to intervene is controversial, as highlighted by the British Paediatric Surveillance Unit’s ongoing survey into preterm surgical ligation incidence (http://www.rcpch.ac.uk/bpsu). Successful active management stops the aforementioned “diastolic steal”; however disappointingly the outcomes, alongside treatment side effects support conservative approach.

Ligation utilises thoracotomy and external clips for duct occlusion. Complications include infection, scoliosis, pneumothorax, and respiratory compromise. Furthermore, unilateral vocal cord paralysis and post-operative falls in cardiac output can prolong admission.

Ibuprofen and indomethacin are common medical ligation alternatives. Indomethacin reduces cerebral oxygenation, risks renal impairment, and in combination with steroids threatens necrotising enterocolitis. Ibuprofen has equal efficacy to indomethacin, but with less renal compromise.

The management of a preterm patent duct is confounded by an ambiguous evidence base. Moreover, relevant National Institute for Clinical Excellence guidelines are 8 years old and reference infant endovascular interventions only. ³ Key advances have occurred since, including the widespread use of pharmacological agents. Furthermore, current data focus solely on neonatologists, disregarding the role of the paediatric cardiologists, despite management commonly involving both sub-specialities.

It is unknown whether neonatology practice varies from that of cardiologists, how either speciality interprets the evidence-base, or the relative importance of factors that determine management decisions. This study aims to:

• ∙ Identify differences between neonatologist and cardiologist practice.

• ∙ Identify management decision thresholds.

• ∙ Evaluate evidence base and guideline interpretations.

Results

In all, 22 cardiologists (11 consultants, 11 registrars) and 27 neonatologists (17 consultants, 10 registrars) completed questionnaires (49/56; response rate 87%).

Within three of four scenarios, there was an agreement of management between neonatologists and cardiologists. More notably, one scenario involving a 24-week gestation 4-week old on continuous positive pressure ventilation with two previous unsuccessful trials of indomethacin for duct closure resulted in no action being taken by 86.4% (19/27) of neonatologists and 45.5% (10/22) of cardiologists, although 33% of cardiologists suggested ligation against 0% of neonatologists (p<0.05). The remaining physicians chose “other”, including referral to the other speciality.

Participants rated on a scale of 1–5, 1 being “not important” and 5 “very important”, the relevance of duct size, haemodynamic effect and clinical significance when considering ligation (Table 1).

Table 1

The relevance of factors considered for surgical ligation of a patent ductus arteriosus.

Median values are presented alongside the respective range of the responses

^* Statistically significant (p<0.05) difference in medians on Mann–Whitney U-test

Clinical significance was the most relevant factor, followed by haemodynamic significance and then ductal size. However, neonatologists weighted greater importance to haemodynamics than cardiologists (p<0.05).

Participants approximated change in relative risk of common comorbidities after active ductal closure, excluding prophylaxis. There was no significant difference between specialities. In both surgical and medical management, clinicians most commonly selected “no change” in risk, except in medical management and intraventricular haemorrhage, where 48.4% selected <50% decrease in risk.

Lastly, using a scale of 1–5, 1 being “0% confident” and 5 being “100% confident”, participants rated confidence in the current evidence base for clinical guidance with a median score of 3 (range: 1–4). In all, 62% of the participants reported their institution had medical preterm management guidelines, whereas 20% had surgical guidelines. In all, 81% agreed that neonatal patent ductus arteriosus management needs improved national/international guidelines, 16% were unsure, and 3% disagreed.