Prognostic indicators after cardiac surgery in children and their relationship with the oxidative stress response

Abstract

ObjectivesTo analyse the trend in lipid peroxidation and antioxidant response as key markers of oxidative stress after paediatric cardiovascular surgery, and compare them with other internationally accepted clinical prognostic indicators. Patients and methodsA prospective study was conducted on 30 children aged one month to 14 years, weight>5kg, undergoing cardiopulmonary bypass surgery. Blood samples were taken just before the intervention, immediately after surgery, and after 18–20h. Cell membrane lipid peroxidation was analysed by quantifying malondialdehyde, as well as measuring total glutathione (oxidised and reduced), as representatives of antioxidant response. An analysis was also performed on clinical variables for establishing a score for the systemic inflammatory response syndrome associated with cardiopulmonary bypass. ResultsThe study included 30 children with a mean age of 4.1 years old (interquartile range [IQR]: 2.7; 8.0). Of these, 62.1% were girls. The standard deviation of the median weight was −0.39 (IQR: −0.76; 0.24), the median height was −0.22 (IQR: −0.74; 0.27), and the median BMI was −0.43 (IQR: −1; 0.45). The final surgery times were divided into 2 parts: total time of extracorporeal circulation, with a mean of 79min (IQR: 52.5; 125.5), and the clamping time, a measurement included in the previous figure with a mean value of 38.5min (IQR: 22; 59). Malondialdehyde increased and glutathione decreased in postoperative time, with clear, statistically significant direct correlation between time of extracorporeal circulation and percentage decrease in total glutathione between preoperative and immediate postoperative time, and a decline between the preoperative and late postoperative. There was a statistical correlation between total glutathione levels at 18–20h postoperatively and the duration of mechanical ventilation and inflammatory systemic response syndrome. ConclusionsSurgery with extracorporeal circulation performed in children activates inflammatory mediators, being maximum after aortic clamping, and improving after the first 24h. The level of oxidative stress activation depends on surgical times. The development of systemic inflammatory response syndrome is associated with longer duration of mechanical ventilation, longer stay in intensive care, higher scores in the Aristotle model and longer surgical times. Those who do not meet criteria for inflammatory response have higher levels of glutathione in first 24h.