Perioperative management of blood glucose during open heart surgery in infants and children

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

This literature review examines the current evidence regarding the potential usefulness of tight glycemic control in pediatric surgical patients. In adults, fluctuations in glucose levels and/or prolonged hyperglycemia have been shown to be associated with poor outcomes with respect to morbidity and mortality. This review begins by summarizing the findings of key papers in adult patients and continues by investigating whether or not similar results have been seen in pediatric patients by performing a comprehensive literature review using Medline (OVID). A database search using the OVID interface and including the search terms (exp glucose) AND (exp surgery) AND (exp Paediatric/pediatric) AND (exp Hypoglycaemia/hypoglycemia) AND (exp Hyperglycaemia/hyperglycemia) yielded a total of 150+ papers, of which 24 fulfilled our criteria. We isolated papers utilizing pediatric patients who were hospitalized due to illness and/or surgery. Our review highlights several difficulties encountered in addressing this potentially useful clinical intervention. An absence of scientifically robust and randomized trials and the existence of several small-powered trials yielding conflicting results mean we cannot recommend tight glycemic control in these patients. Differences in study design and disagreements concerning the crucial stage of surgery where hyperglycemia becomes important are compounded by an over-reliance on the discretion of clinicians in the absence of well described treatment protocols. Closer inspection of key papers in adult patients identified fundamental discrepancies between exact definitions of both hyperglycemia and hypoglycemia. This lack of consensus, along with a fear of inducing iatrogenic hypoglycemia in pediatric patients, has resulted in professional bodies advising against this form of intervention. In conclusion, we cannot recommend use of tight glycemic control in pediatric surgical patients due to unclear glucose definitions, unclear thresholds for treatment, and the unknown long-term effects of iatrogenic hypoglycemia on the developing body and brain.

Neurological injury and anesthetic neurotoxicity following neonatal cardiac surgery: does the head rule the heart or the heart rule the head?

The improvements in care of children with heart disease have resulted in a major decrease in mortality and increased attention to adverse events and quality of survival. There is important neurological morbidity in children with congenital heart disease. Some problems such as stroke or seizure may be immediately apparent, but others, such as learning disability and motor delay emerge over time. The etiology is multifactorial and includes genetic, procedural and social causes. Only some factors are modifiable. Over the last decade, evidence has been presented that anesthetic drugs may be a potential cause of CNS morbidity. Neonates and infants may be particularly vulnerable to this. The purpose of this article is to describe the multiple known causes of neurodevelopmental impairment in children with heart disease, including anesthetic agents, and to explore the relationship between congenital heart disease and its treatment in this regard.