Risk factors and early outcomes associated with prolonged pleural effusion/chylothorax after paediatric cardiac surgery

Abstract

Objectives: Prolonged pleural effusion/chylothorax (PPE/C) is a less investigated complication following paediatric cardiac surgery, and its true incidence, risk factors and impact on postoperative outcomes are not well described. We aim to address these gaps in knowledge using data from a prospective, multicentre study.

Methods: Data on 9 post-operative morbidities (unplanned reinterventions, extracorporeal life support, necrotising enterocolitis, PPE/C, renal replacement therapy, major adverse events, acute neurological events, feeding issues and postsurgical infection) were prospectively collected at 5 UK centres between 2015 and 2017, following paediatric cardiac surgery. Incidence of PPE/C, associations with procedure types, and risk factors were described. Mortality (30-day and 6-month) and hospital length of stay (HLoS) were compared between those with isolated PPE/C, single non-PPE/C morbidity, no morbidity, multimorbidity PPE/C and non-PPE/C multimorbidity.

Results: A total of 3090 procedures (2861 patients) were included (median age, 228 days). There were 202 PPE/C (incidence of 6.5%), occurring at a median of 6 days postoperatively (interquartile range: 3-10). PPE/C was associated with excess early mortality only when complicating scenarios where at least 2 other post-operative morbidities occurred. On average PPE/C is associated with 8 more HLoS days, but the relative impact is greatest when comparing isolated PPE/C with no morbidity (P < 0.001), whereas in multimorbidity scenarios, PPE/C does not significantly contribute to an increase of HLoS.

Conclusions: Addition of PPE/C increases mortality but not HLoS in multimorbidity and HLoS only in single morbidity scenarios. This reinforces the important role of prevention, early detection and management of PPE/C in complex situations.

Keywords: Chylothorax; Congenital heart disease; Morbidity; Paediatric cardiac surgery; Pleural effusion; Prospective study.

Graphical abstract

Figure 1:

Impact of prolonged pleural effusion/chylothorax (PPE/C) on early outcomes after congenital heart disease surgery, by association with other post-operative morbidities. (A) 30-day mortality, (B) 6-month mortality and (C) hospital length of stay (HLoS). ECLS, extracorporeal circulatory life support. For panels (A) and (B), P values are from time-varying multiple-records survival analysis. For panel (C), P values are from linear mixed models for the whole cohort (same P values for analysis restricted to discharged alive).