Glicemia perioperatória e complicações pós-operatórias em cirurgia cardíaca pediátrica

Abstract

Background: Anesthesia for pediatric cardiac surgery is systematically performed in severely ill patients under abnormal physiological conditions. In the intraoperative period, there are significant variations in blood volume, body temperature, plasma composition, and tissue blood flow, in addition to activation of inflammation, with important consequences. Serial measurements of blood glucose levels can indicate states of exacerbation of the neuroendocrine-metabolic response to trauma, serving as prognostic markers of morbidity in that population.

Does tight glycemic control improve outcomes in pediatric patients undergoing surgery and/or those with critical illness?

“…Children have a higher recommended optimal blood glucose level of 110–126 mg/dL, which is higher than in adults,30 and levels >140 mg/dL can be classed as hyperglycemia 22. The perioperative period is an extremely unusual period of time for the body characterized by extremes in blood volume, body temperature, plasma composition, and tissue blood flow, as reported by Alves et al9 Further, Filho et al stress the importance of selecting an appropriate target group because the consequences of any fluctuations in blood glucose depend on the intervention performed and preoperative morbidity 10…”

“…High glucose levels affect a number of other aspects of physiology, some of which are hypothesized to play a role in postoperative outcomes, including oxidative injury, a proinflammatory response, clotting abnormalities, vascular reactivity, and decreased immune system effectiveness 7. It is thought that hyperglycemia compromises all major components of the innate immune system, including phagocytosis and opsonization,9 causing glycosylation and inactivation of circulating immunoglobulins that contributes to an increased risk of infection and is an important cause of postoperative mortality in vulnerable individuals 2. Importantly, coagulopathies and hyperglycemia tend to occur simultaneously and correlate with the magnitude of trauma and wound size 9,10…”

“…Alves et al9 found a statistically significant difference between mean blood glucose in the first 24 hours and postoperative complications, compared with Polito et al25 who found that outcomes were insignificant until 72 hours after surgery 25. One study investigated the incidence of mediastinitis following median sternotomy; a procedure that has a mortality rate of 6%–23% 26.…”

“…These patients may have a prolonged hospital stay and may require extended antibiotic therapy, but Ghafoori et al showed that persistent postoperative hyperglycemia was more predictive of adverse outcomes than the initial postoperative blood glucose value 26. A key finding of Alves et al was the importance of exogenous corticosteroid administration and the use of extracorporeal circulation as two specific risk factors for development of secondary complications 9. Postoperative hyperglycemia is all-encompassing according to Ulate et al, and the intensity, duration and variability are all associated with poor outcomes in critically ill children 8.…”

“…A meta-analysis carried out by Ng et al found that tight blood glucose control caused hypoglycemia in one of four RCTs studied, but due to discrepancies in the definition of hypoglycemia and a lack of data concerning other secondary cardiovascular outcomes, they stress the need for further study 38. A major factor in the generation of intraoperative hyperglycemia is glucocorticoid administration 9,37…”