Corticosteroids in Pediatric Heart Surgery: Myth or Reality

Abstract

Background: Corticosteroids have been administered prophylactically for more than 60 years in pediatric heart surgery, however, their use remains a matter of debate. There are three main indications for corticosteroid use in pediatric heart surgery with the use of cardiopulmonary bypass (CPB): (1) to blunt the systemic inflammatory response (SIRS) induced by the extracorporeal circuit; (2) to provide perioperative supplementation for presumed relative adrenal insufficiency; (3) for the presumed neuroprotective effect during deep hypothermic circulatory arrest operations. This review discusses the current evidence behind the use of corticosteroids in these three overlapping areas.Materials and Methods: We conducted a structured research of the literature using PubMed and MEDLINE databases to November 2017 and additional articles were identified by cross-referencing.Results: The evidence suggests that there is no correlation between the effect of corticosteroids on inflammation and their effect on clinical outcome. Due to the limitations of the available evidence, it remains unclear if corticosteroids have an impact on early post-operative outcomes or if there are any long-term effects. There is a limited understanding of the hypothalamic-pituitary-adrenal axis function during cardiac surgery in children. The neuroprotective effect of corticosteroids during deep hypothermic circulatory arrest surgery is controversial.Conclusions: The utility of steroid administration for pediatric heart surgery with the use of CPB remains a matter of debate. The effect on early and late outcomes requires clarification with a large multicenter randomized trial. More research into the understanding of the adrenal response to surgery in children and the effect of corticosteroids on brain injury is warranted.

The Peacock study: feasibility of the dynamic characterisation of the paediatric hypothalamic-pituitary-adrenal function during and after cardiac surgery

“…Surgery with use of cardiopulmonary bypass (CPB) is a potent activator of the systemic inflammatory response and hence of the HPA axis. It is believed that this activation is augmented in the paediatric population [8]. Glucocorticoids have been used in paediatric heart surgery for more than 50 years, but there is still an ongoing debate around their utility [9].…”

“…Indeed, an accurate assessment of the HPA axis requires frequent cortisol testing [11]. Most of the studies to date have measured cortisol at a few time points over long periods [8]. Another common limitation of these studies is that they attempted to assess HPA axis function after potent corticosteroids have been given preoperatively.…”

“…We will be assessing the tolerability and safety of the device in children as part of the main study. In a recent literature review, we found that highest number of cortisol measurements achieved by all the studies published to date was 10-time points over 48 h and in almost all the studies glucocorticoids were administered on anaesthetic induction that certainly prevented a meaningful assessment [8]. The Peacock study aims to tackle these previous limitations by avoiding pre-operative steroids and frequently measuring cortisol/ cortisone at the tissue level.…”

Systemic Inflammatory Response to Cardiopulmonary Bypass in Pediatric Patients and Related Strategies for Prevention

“…In general though, several broad pathophysiologic categories can be defined as follows ( Fig. 1): [1] complement activation; [2] initiation of coagulation, fibrinolytic, and kallikrein cascades; [3] neutrophil activation with degranulation and proteolytic enzyme release; [4] oxygen-derived free radical production; [5] endotoxin and cytokine release; and [6] nitric oxide (NO), endothelin-1 (ET-1), and platelet-activating factor (PAF) production by "primed" endothelial cells. The sequential activations of these cascades coupled with extensive interactions result in a sustained and amplified systemic inflammatory response syndrome (SIRS) [15][16][17][18][19][20].…”

“…Cardiopulmonary bypass (CPB) in pediatric patients is associated with generalized activation of both innate and acquired immunity, and this phenomenon is exaggerated at the extremes of age [1,2]. The systemic inflammatory response to CPB occurs in response to multiple nonphysiologic stimuli, including exposure of blood elements to foreign surfaces, nonpulsatile perfusion, periods of relative hypoperfusion, alterations in temperature (especially hypothermia), and ischemia-reperfusion injury [3,4].…”