Fluid Overload in Pediatric Univentricular Patients Undergoing Fontan Completion

Background: Fluid overload (FO) is known to occur frequently after pediatric cardiac surgery and is associated with morbidity and mortality. Fontan patients are at risk to develop FO due to their critical fluid balance. Furthermore, they need an adequate preload in order to maintain adequate cardiac output. This study aimed to identify FO in patients undergoing Fontan completion and the impact of FO on pediatric intensive care unit (PICU) length of stay (LOS) and cardiac events, defined as death, cardiac re-surgery or PICU re-hospitalization during follow-up. Methods: In this retrospective single center study, the presence of FO was assessed in 43 consecutive children undergoing Fontan completion. Results: Patients with more than 5% maximum FO had an extended PICU LOS (3.9 [2.9–6.9] vs. 1.9 [1.0–2.6] days; p < 0.001) and an increased length of mechanical ventilation (21 [9–121] vs. 6 [5–10] h; p = 0.001). Regression analysis demonstrated that an increase of 1% maximum FO was associated with a prolonged PICU LOS of 13% (95% CI 1.042–1.227; p = 0.004). Furthermore, patients with FO were at higher risk to develop cardiac events. Conclusions: FO is associated with short-term and long-term complications. Further studies are needed to determine the impact of FO on the outcome in this specific population.