Evaluation of adrenal function in critically ill children

Cortisol response in children with cancer and fever during chemotherapy: A prospective, observational study using random serum cortisol levels

BACKGROUND

Glucocorticoids are crucial components of the treatment of leukemia and lymphoma. High doses can lead to suppression of the hypothalamic-pituitary-adrenal (HPA) axis and be causative for an impaired stress response during infection. This study aims to evaluate the cortisol response in pediatric oncologic patients during febrile episodes.

METHODS

Totally, 75 children and adolescents (5 months-18 years) with fever during chemotherapy were consecutively enrolled in this study. In total, 47 patients received glucocorticoids as part of their treatment. Random serum cortisol and adrenocorticotropic hormone (ACTH) were analyzed in every patient. A low cortisol response (LCR) was defined as a cortisol level < 14.6 μg/dL.

RESULTS

In total, 52 (69%) patients had a cortisol level < 14.6 μg/dL during fever. There was no significant difference between patients who received glucocorticoids and those who did not. Significantly lower cortisol levels were measured ≤7 days after last glucocorticoid intake compared to later time points. Nearly all patients treated with dexamethasone or prophylactic posaconazole demonstrated a LCR under stress (fever).

CONCLUSION

The incidence of an impaired HPA axis in pediatric cancer patients might be underestimated since 69% of the children in our study had a LCR during fever. Intake of dexamethasone, posaconazole and a time period of ≤7 days from the last glucocorticoid intake were additional risk factors for an LCR. However, we could not confirm that patients with a LCR fared worse than patients with a high cortisol response (HCR). Therefore, a different cortisol threshold may be necessary for defining an impaired HPA axis in febrile oncologic patients without concomitant symptoms of AI.

Relation between Baseline Total Serum Cortisol Level and Outcome in Pediatric Intensive Care Unit

Elevated cortisol level is an component of the stress response. However, some patients have low cortisol levels; a condition termed: critical illness-related corticosteroid insufficiency (CIRCI). Basal cortisol levels during PICU admission may be related to outcome. This prospective cohort study aimed to assess basal total serum cortisol levels and their relation to outcome in PICU. The study included 81 children over 6 months. Total serum cortisol was assessed using an early morning sample. The severity of illness was assessed using the PRISM-III score. Outcome measures included mechanical ventilation duration, use of inotropic support, length of stay, mortality. Comparison between patients' subgroups according to total serum cortisol levels revealed significantly higher PRISM-III score in patients with total serum cortisol levels. In addition, those patients had a significantly higher mortality rate when compared with patients with low and normal total serum cortisol levels. Multivariate logistic regression analysis recognized high total serum cortisol level and PRISM-III score as significant predictors of mortality. We concluded that PRISM-III score and elevated total serum cortisol levels are significant predictors of mortality in the PICU. Although CIRCI is prevalent in this population, it wasn't associated with an increased mortality rate.

EVALUATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS IN A PAEDIATRIC INTENSIVE CARE UNIT

Background

Relative adrenal insufficiency (RAI) is the inadequate production of cortisol due to dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis during a severe illness. We evaluated the HPA axis and RAI in a tertiary pediatric intensive care unit (PICU).

Methods

A total of 100 PICU patients were included in this prospective cohort study. Basal serum levels of adrenocorticotropic hormone (ACTH), cortisol values were compared with those in the control group. A low-dose ACTH stimulation test was performed in patients with basal cortisol levels below 18 µg/dL.

Results

The basal cortisol levels of the PICU patients were significantly higher than those of the control group (P < 0.05). All tested patients (n= 24) had delta cortisol levels > 9 µg/dL and a peak cortisol response > 18 µg/dL. Basal cortisol levels were positively correlated with Pediatric Risk of Mortality (PRISM) III scores (P < 0.05; r = 0.363). The basal or stimulated cortisol levels of the patients who received glucocorticoid treatment were higher than the cut-off levels.

Conclusions

High basal or stimulated cortisol levels are indicative of disease severity in the acute phase of stress. Patients with very high cortisol levels should be particularly carefully monitored because of the high mortality risk.

Salivary biomarkers may measure stress responses in critically ill children

OBJECTIVE

Measurement of salivary biomarkers can provide important information regarding hypothalamic-pituitary-adrenal axis activity both under normal conditions as well as in response to psychological or physical stress. Our aim was to correlate salivary stress markers, such as cortisol, α-amylase and immunoglobulin A, with the Pediatric Risk Index Score of Mortality, underlying disease (pathologic, trauma and postoperative), need for mechanical ventilation/sedation and time lag between onset of illness and admission in children admitted in the pediatric intensive care unit.

METHODS

We enrolled 79 pediatric intensive care unit patients (2-14 years) over a 2-year period, which satisfy the including criteria, but finally salivary biomarkers were evaluated in 65 patients. Saliva samples were collected within 24 h of admission at 8 a.m., 2 p.m. and 8 p.m. to examine potential disruption of circadian rhythm.

RESULTS

Overall, the salivary biomarkers were increased; specifically, median values were (a) cortisol at 8 a.m.: 50.04 nmol/L, 2 p.m.: 30.69 nmol/L and 8 p.m.: 247.12 nmol/L; (b) α-amylase: at 8 a.m.: 22.567 U/L; 2 p.m.: 22.702 U/L and 8 p.m.: 21.484 U/L and (c) IgA at 8 a.m.: 95.10 mg/dL, 2 p.m.: 88.55 mg/dL and 8 p.m.: 80.80 mg/dL. Significantly higher levels were demonstrated in children younger than 6 years and those with Pediatric Risk Index Score of Mortality ⩾8 upon admission. Disturbances in circadian rhythm were observed. Cortisol circadian rhythm disturbance was observed only in children with Pediatric Risk Index Score of Mortality score ⩾8 upon admission while maintaining normal α-amylase circadian rhythm, which was associated with less than 3 days hospitalization in pediatric intensive care unit. No daily variance in IgA was observed.

CONCLUSION

Salivary biomarkers may serve, in critically ill children, as a sensitive, non-invasive method, important for the early recognition of those at high risk and guiding intervention, before clinical deterioration, promoting the quality of health care in pediatric population.

Elevated Baseline Cortisol Levels Are Predictive of Bad Outcomes in Critically Ill Children

OBJECTIVE

The definition of an adequate adrenal response in critically ill children continues to be controversial. We aimed to evaluate the cortisol levels at baseline and after adrenocorticotropin (ACTH) stimulation and determine their association to clinical outcome of critically ill children.

METHODS

All children who underwent an ACTH test in the pediatric intensive care unit (PICU) in a tertiary medical center between 2006 and 2013 were included in the study. Data on age, sex, diagnosis, vasoactive-inotropic score, length of pediatric intensive care unit stay, and mortality were obtained. Laboratory variables included hematologic and chemistry data, arterial lactate, and total plasma cortisol levels at baseline and after ACTH stimulation.

RESULTS

Ninety-nine patients (61 males; median [range] age, 2 [0-204] months) were enrolled. The mortality rate of children with a baseline cortisol level of 600 nmol/L or greater was 36% (12/33 patients) versus 18% (12/66 patients) for children with a baseline cortisol level of less than 600 nmol/L (odds ratio, 2.6 [95% confidence interval, 1-6.6]; P = 0.05). There was a positive correlation between baseline cortisol and lactate levels (r = 0.40, P < 0.0001), vasoactive-inotropic scores (r = 0.24, P = 0.02), and mortality (P = 0.05). There was no correlation between peak cortisol measured at the ACTH test or the delta increment of cortisol from baseline and mortality.

CONCLUSIONS

A high baseline cortisol level in critically ill children was associated with more severe illness, higher lactate level, and a higher mortality rate. Routine baseline cortisol assessment is recommended to identify patients at high mortality risk.

Diagnosis and management of pediatric adrenal insufficiency

BACKGROUND

Adrenal insufficiency (AI) is a wellknown cause of potentially life-threatening disorders. Defects at each level of the hypothalamic-pituitary-adrenal axis can impair adrenal function, leading to varying degrees of glucocorticoid (GC) deficiency. Iatrogenic AI induced by exogenous GCs is the most common cause of AI. The criteria for the diagnosis and management of iatrogenic AI, neonatal AI, and critical illness-related corticosteroid insufficiency (CIRCI) are not clear.

DATA SOURCES

We reviewed the recent original publications and classical data from the literature, as well as the clinical, diagnostic and management strategies of pediatric AI.

RESULTS

Practical points in the diagnosis and management of AI with an emphasis on iatrogenic AI, neonatal AI, and CIRCI are provided. Given the lack of sensitive and practical biochemical tests for diagnosis of subtle AI, GC treatment has to be tailored to highly suggestive clinical symptoms and signs. Treatment of adrenal crisis is well standardized and patients almost invariably respond well to therapy. It is mainly the delay in treatment that is responsible for mortality in adrenal crisis.

CONCLUSIONS

Education of patients and health care professionals is mandatory for timely interventions for patients with adrenal crisis.

Comparison of Adrenal Suppression between Etomidate and Dexmedetomidine in Children with Congenital Heart Disease

Background

The aim of this study was to compare plasma cortisol concentration during anesthesia of children with congenital heart disease who received dexmedetomidine (DEX) with those who received etomidate (ETO).

Material/Methods

We recruited 99 ASA physical status II–III pediatric patients scheduled for congenital heart disease (CHD) corrective surgery and divided into them into 3 groups. Group DEX received an infusion of DEX intravenously with a bolus dose of 0.5 μg·kg⁻¹ within 10 min during anesthesia induction, followed by a maintenance dose of DEX 0.5 μg·kg⁻¹·h⁻¹. Group ETO received ETO intravenously with a bolus dose of 0.3 mg·kg⁻¹ without a maintenance dose. Group CON received routine anesthetics as controls. The preset timepoints were: before anesthesia induction (T0), at the end of induction (T1), 30 min after anesthesia induction (T2), at the time of aortic and inferior vena catheterization (T3), and at 180 min (T4) and 24 h (T5) after anesthesia induction.

Results

The cortisol concentration decreased gradually after anesthesia induction in all groups, and returned to baseline values after 24 h. The cortisol concentration was significantly lower in Group ETO children than in Group DEX or group CON at T4.

Conclusions

The plasma concentrations of cortisol decreased in CHD children after the operation, but returned to baseline after 24 h of anesthesia induction. The adrenal cortex function inhibition induced by ETO in CHD children is longer and more serious than that induced by DEX (if any) during the preoperative period.