Use of Indirect Calorimetry to Detect Overfeeding in Critically Ill Children: Finding the Appropriate Definition.

OBJECTIVES: Overfeeding during critical illness is associated with adverse effects such as metabolic disturbances and increased risk of infection. Because of the lack of sound studies with clinical endpoints, overfeeding is arbitrarily defined as the ratio caloric intake/measured resting energy expenditure (mREE) or alternatively as a comparison of measured respiratory quotient (RQ) to the predicted RQ based on the macronutrient intake (RQmacr). We aimed to compare definitions of overfeeding in critically ill mechanically ventilated children based on mREE, RQ, and caloric intake to find an appropriate definition. METHODS: Indirect calorimetry measurements were performed in 78 mechanically ventilated children, median age 6.3 months. Enteral and/or parenteral nutrition was provided according to the local guidelines. Definitions used to indicate overfeeding were the ratio caloric intake/mREE of >110% and >120% and by the measured RQ > RQmacr + 0.05. RESULTS: The proportion of patients identified as overfed varied widely depending on the definition used, ranging from 22% (RQ > RQmacr + 0.05), to 40% and 50% (caloric intake/mREE of >120% and >110%, respectively). Linear regression analysis showed that all patients would be identified as overfed with the definition RQ > RQmacr + 0.05 when the ratio caloric intake/mREE exceeded 165%. Caloric intake was higher in children with a standard deviation-score weight for age <-2. CONCLUSIONS: The proportion of mechanically ventilated patients identified as overfed ranged widely depending on the definition applied. These currently used definitions fail to take into account several relevant factors affecting metabolism during critical illness and are therefore not generally applicable to the pediatric intensive care unit population.

Prospective evaluation and follow-up of nutritional status of children hospitalized in secondary-care level hospitals: a multicentre study.

Although disease-associated undernutrition is still an important problem in hospitalized children that is often underrecognized, follow-up studies evaluating post-discharge nutritional status of children with undernutrition are lacking. The aim of this multicentre prospective observational cohort study was to assess the rate of acute undernutrition (AU) and/or having a high nutritional risk (HR) in children on admission to seven secondary-care level Dutch hospitals and to evaluate the nutritional course of AU/HR group during admission and post-discharge. STRONGkids was used to indicate HR, and AU was based on anthropometric data (z-score < -2 for weight-for-age (WFA; <1 year) or weight-for-height (WFH; ≥1 year)). In total, 1985 patients were screened for AU/HR over a 12-month period. On admission, AU was present in 9.9% of screened children and 6.2% were classified as HR; 266 (13.4%) children comprised the AU/HR group (median age 2.4 years, median length of stay 3 days). In this group, further nutritional assessment by a dietitian during hospitalization occurred in 44% of children, whereas 38% received nutritional support. At follow-up 4-8 weeks post-discharge, 101 out of orginal 266 children in the AU/HR group (38%) had available paired anthropometric measurements to re-assess nutrition status. Significant improvement of WFA/WFH compared to admission (-2.48 vs. -1.51 SD; p < 0.001) and significant decline in AU rate from admission to outpatient follow-up (69.3% vs. 35.6%; p < 0.001) were shown. In conclusion, post-discharge nutritional status of children with undernutrition and/or high nutritional risk on admission to secondary-care level pediatric wards showed significant improvement, but about one-third remained undernourished. Findings warrant the need for a tailored post-discharge nutritional follow-up.

Pathophysiological aspects of hyperglycemia in children with meningococcal sepsis and septic shock: a prospective, observational cohort study.

INTRODUCTION: The objective of this study was to investigate the occurrence of hyperglycemia and insulin response in critically ill children with meningococcal disease in the intensive care unit of an academic children's hospital. METHODS: Seventy-eight children with meningococcal disease were included. The group was classified into shock non-survivors, shock survivors and sepsis survivors. There were no sepsis-only non-survivors. The course of laboratory parameters during 48 hours was assessed. Insulin sensitivity and ß-cell function on admission were investigated by relating blood glucose level to insulin level and C-peptide level and by homeostasis model assessment (HOMA) [ß-cell function (HOMA-%B) and insulin sensitivity (HOMA-%S)]. RESULTS: On admission, hyperglycemia (glucose >8.3 mmol/l) was present in 33% of the children. Shock and sepsis survivors had higher blood glucose levels compared with shock non-survivors. Blood glucose level on admission correlated positively with plasma insulin, C-peptide, cortisol, age and glucose intake. Multiple regression analysis revealed that both age and plasma insulin on admission were significantly related to blood glucose. On admission, 62% of the hyperglycemic children had overt insulin resistance (glucose >8.3 mmol/l and HOMA-%S <50%); 17% had ß-cell dysfunction (glucose >8.3 mmol/l and HOMA-%B <50%) and 21% had both insulin resistance and ß-cell dysfunction. Hyperglycemia was present in 11% and 8% of the children at 24 and 48 hours after admission, respectively. CONCLUSIONS: Children with meningococcal disease often show hyperglycemia on admission. Both insulin resistance and ß-cell dysfunction play a role in the occurrence of hyperglycemia. Normalization of blood glucose levels occurs within 48 hours, typically with normal glucose intake and without insulin treatment.

Disturbance of glucose homeostasis after pediatric cardiac surgery.

This study aimed to evaluate the time course of perioperative blood glucose levels of children undergoing cardiac surgery for congenital heart disease in relation to endogenous stress hormones, inflammatory mediators, and exogenous factors such as caloric intake and glucocorticoid use. The study prospectively included 49 children undergoing cardiac surgery. Blood glucose levels, hormonal alterations, and inflammatory responses were investigated before and at the end of surgery, then 12 and 24 h afterward. In general, blood glucose levels were highest at the end of surgery. Hyperglycemia, defined as a glucose level higher than 8.3 mmol/l (>150 mg/dl) was present in 52% of the children at the end of surgery. Spontaneous normalization of blood glucose occurred in 94% of the children within 24 h. During surgery, glucocorticoids were administered to 65% of the children, and this was the main factor associated with hyperglycemia at the end of surgery (determined by univariate analysis of variance). Hyperglycemia disappeared spontaneously without insulin therapy after 12-24 h for the majority of the children. Postoperative morbidity was low in the study group, so the presumed positive effects of glucocorticoids seemed to outweigh the adverse effects of iatrogenic hyperglycemia.

Management of hyperglycemia in the pediatric intensive care unit; implementation of a glucose control protocol.

OBJECTIVE: To evaluate a stepwise nurse-driven glucose control protocol for the treatment of hyperglycemia in critically ill pediatric patients. SETTING: Academic pediatric intensive care unit. DESIGN: Prospective observational study. PATIENTS: A total of 50 consecutively admitted critically ill children with hyperglycemia >8 mmol/L (>145 mg/dL) were included and treated according to the glucose control protocol. MEASUREMENTS AND MAIN RESULTS: Demographic data and clinical parameters were collected and different steps in the protocol were evaluated. Data were expressed as medians with interquartile ranges. Fifty children (28 boys), aged 3.5 yrs (range, 1.2 -9.3 yrs) were treated in 18 mos. Forty-two children had multiple organ failure. Eight children died. Insulin treatment was initiated 4 hrs after the first episode of hyperglycemia was documented (median blood glucose, 11.4 mmol/L, [207 mg/dL] [9.7-14.5 mmol/L, 176-264 mg/dL]). Blood glucose was <8 mmol/L (<145 mg/dL) within 12 hrs of initiating insulin therapy in 47 (94%) of 50 children (median, 5 hrs). Duration of treatment was 34 hrs (17-72 hrs) and the maximum insulin dose ranged between 20 and 200 mIU/kg/hr (median, 70 mIU/kg/hr). Episodes of severe hypoglycemia <2.2 mmol/L (<47 mg/dL) did not occur. CONCLUSION: The use of a stepwise nurse-driven glucose control protocol resulted in normoglycemia within 12 hrs for 94% of the children involved. Episodes of severe hypoglycemia did not occur. We conclude that the glucose control protocol is effective in treating hyperglycemia in critically ill children. Further studies are necessary to assess safety before the protocol could also be implemented in other pediatric intensive care units.

Baseline insulin/glucose ratio as a marker for the clinical course of hyperglycemic critically ill children treated with insulin.

OBJECTIVE: The objective of this study was to investigate the relations of baseline insulin/glucose ratio to the clinical course of critically ill children. Such information will provide insight into the pathophysiologic mechanisms leading to hyperglycemia and will optimize preventive and therapeutic measures for hyperglycemia in critically ill children. METHODS: Sixty-four consecutively admitted critically ill children with hyperglycemia, defined as a blood glucose level higher than 8 mmol/L (>145 mg/dL) and treated with insulin according to a glucose-control protocol, were included. Demographic data and clinical and laboratory parameters were collected. Insulin sensitivity was investigated by calculating the ratio of insulin to the blood glucose level just before the start of insulin administration. Results are expressed as median (range). RESULTS: Sixty-four children (24 girls) 7.0 y of age (0.3-16.9 y) with various diagnoses were included. A hyperinsulinemic response, indicated by an increased insulin/glucose ratio (>18 pmol/mmol), was seen in 55% of children. The durations of insulin therapy, mechanical ventilation, and pediatric intensive care unit length of stay in children with a hyperinsulinemic response were longer than in children with a hypoinsulinemic response. CONCLUSION: Hyper- and hypoinsulinemic responses play a role in the occurrence of hyperglycemia in critically ill children. Each is associated with a particular clinical course after the initiation of insulin therapy. It would be worthwhile to further investigate if the insulinemic response to hyperglycemia, determined by the insulin/glucose ratio in combination with the type of organ dysfunction, could be used in clinical practice to determine the need for insulin therapy.