Adrenal insufficiency in critical illness

Critical Illness-Related Corticosteroid Insufficiency (CIRCI) After Pediatric Cardiac Surgery

Although current studies do not support the routine use of corticosteroids after cardiopulmonary bypass in pediatric patients, there is incomplete understanding of the potential hemodynamic contribution of postoperative critical illness-related corticosteroid insufficiency in the intensive care unit. By reviewing the available studies and underlying pathophysiology of these phenomena in critically ill neonates, we can identify a subset of patients that may benefit from optimal diagnosis and treatment of receiving postoperative steroids. A suggested algorithm used at our institution is provided as a guideline for treatment of this high-risk population.

Hypothalamic-Pituitary Axis Function and Adrenal Insufficiency in COVID-19 Patients

The outbreak of COVID-19 has affected more than half a billion people worldwide and caused more than 6 million deaths since 2019. The responsible virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), primarily affects the lungs, but it has multisystemic effects. It is well known that dysfunction of multiple endocrine organs may occur during or after COVID-19. Impairment of the hypothalamic-pituitary-adrenal (HPA) axis is of utmost importance as it may lead to death if went undiagnosed. SARS-CoV-2 may cause both primary and secondary adrenal insufficiencies (AIs). The clinical manifestations of AI are generally non-specific and might be attributed to the complications caused by the infection itself. The underlying pathogenetic mechanisms were explained by the immunogenic, vascular effects of the infection or the direct effects of the virus. The diagnosis of AI in critically ill patients with COVID-19 is not straightforward. There is lack of consensus on the cut-off values of basal serum cortisol levels and stimulation tests during the disease. Here we review the literature with a special regard on the evaluation of the HPA axis in patients with COVID-19. We conclude that the possibility of AI should always be kept in mind when dealing with patients with COVID-19, and repeated basal cortisol measurements and the ACTH stimulation test results could guide the clinician during the diagnostic process.

New insight of adrenal responses in premature neonates versus full term neonates in critical care setting.. [DOI: 10.1101/2020.07.15.20154849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background

Adequate adrenocortical function is essential for survival of critically ill neonates. Although most of them display elevated plasma cortisol concentrations, which reflects activation of the hypothalamic pituitary adrenal axis (HPA), yet; adrenocortical insufficiency is seen in septic shock. Objectives: Evaluate the HPA response in critically ill neonates with shock.

Methods

this prospective observational Participant: a total of 60 neonates divided into 3 groups;(A) 30 critical ill neonates with septic shock on inotropic support, (B)15 patients with sepsis with no inotropic support and(C) control group(n=15). Intervention: a single diurnal ACTH reading and two readings for serum cortisol level (diurnal and nocturnal).

Results

Gram negative organism was more prevalent among the patients; 53%, 63% in groups A and B respectively. Group A showed Significant statistical hypotension before vasopressor drug administration (p<0.001) as compared to both groups. Group A showed Significant statistical improvement of blood pressure after vasopressor drug administration (p<0.001) as compared to both groups B, C. Serum cortisol was significantly higher in group A(57.21±24.31) and B (48.01±18.27), while it was lower in group C(19.57±16.05). A highly statistically significant rise of serum cortisol level(p=0.000) and ACTH(p=0.000) in group A when was compared to the other two groups.

Conclusion

This study introduced a new pattern of serum cortisol response in neonates ranging from very high cortisol level to a near normal values; highlighting a state of glucocorticoid resistance in neonates and relative adrenal insufficiency.

Cosyntropin testing does not predict response to glucocorticoids in community-acquired pneumonia in a randomized controlled trial

OBJECTIVE

Glucocorticoids have been shown to improve outcome in community-acquired pneumonia (CAP). However, glucocorticoids have potential side-effects, and treatment response may vary. It is thus crucial to select patients with high likelihood to respond favourably. In critical illness, cosyntropin testing is recommended to identify patients in need for glucocorticoids. We investigated whether cosyntropin testing predicts treatment response to glucocorticoids in CAP.

DESIGN

Predefined secondary analysis of a randomized controlled trial.

PATIENTS

Hospitalized patients with CAP.

MEASUREMENTS

We performed 1 µg cosyntropin tests in a randomized trial comparing prednisone 50 mg for 7 days to placebo. We investigated whether subgroups based on baseline and stimulated cortisol levels responded differently to glucocorticoids with regard to time to clinical stability (TTCS) and other outcomes by inclusion of interaction terms into statistical models.

RESULTS

A total of 326 patients in the prednisone and 309 patients in the placebo group were evaluated. Neither basal cortisol nor a Δcortisol <250 nmol/L after stimulation nor the combination of basal cortisol and Δcortisol predicted treatment response as measured by TTCS (all P for interaction >0.05). Similarly, we found no effect modification with respect to mortality, rehospitalization, antibiotic treatment duration or CAP-related complications (all P for interaction >0.05). However, glucocorticoids had a stronger effect on shortening length of hospital stay in patients with a baseline cortisol of ≥938 nmol/L (P for interaction = 0.015).

CONCLUSIONS

Neither baseline nor stimulated cortisol after low-dose cosyntropin testing at a dose of 1 µg predicted glucocorticoid responsiveness in mild to moderate CAP. A treatment decision for or against adjunct glucocorticoids in CAP should not be made depending on cortisol values or cosyntropin testing results.

Clinical picture and the treatment of TBI-induced hypopituitarism

Traumatic brain injury (TBI) is an important public health problem with an increasing incidence in the last years. Relatively few cases are fatal; most individuals will survive and, in the long-term, the sequalae of TBI will include neuroendocrine dysfunctions with a much higher frequency than previously suspected. Patients who develop hypopituitarism after TBI present manifestations due to the number of deficient hormones, severity of hormonal deficiency, and the duration of hypopituitarism without diagnosis and treatment. The clinical spectrum of hypopituitarism is very large and many signs and symptoms of TBI survivors such as fatigue, concentration difficulties, depressive symptoms are nonspecific and overlap with symptoms of post-traumatic stress disorder and variably severe hypopituitarism related to brain damage remaining undiagnosed. This can explain why the diagnosis of hypopituitarism is often missed or delayed after this condition with potentially serious and hazardous consequences for the affected patients. Moreover, clinical experience cumulatively suggests that TBI-associated hypopituitarism is associated with poor recovery and worse outcome, since post-traumatic hypopituitarism is independently associated with cognitive impairment, poor quality of life, abnormal body composition, and adverse metabolic profile. In the present review, the current data related to clinical consequences of pituitary dysfunction after TBI in adult patients and therapeutic approaches are reported.

The role of autoimmunity in pituitary dysfunction due to traumatic brain injury

PURPOSE

Traumatic brain injury (TBI) is one of the most common causes of mortality and long-term disability and it is associated with an increased prevalence of neuroendocrine dysfunctions. Post-traumatic hypopituitarism (PTHP) results in major physical, psychological and social consequences leading to impaired quality of life. PTHP can occur at any time after traumatic event, evolving through various ways and degrees of deficit, requiring appropriate screening for early detection and treatment. Although the PTHP pathophysiology remains to be elucitated, on the basis of proposed hypotheses it seems to be the result of combined pathological processes, with a possible role played by hypothalamic-pituitary autoimmunity (HPA). This review is aimed at focusing on this possible role in the development of PTHP and its potential clinical consequences, on the basis of the data so far appeared in the literature and of some results of personal studies on this issue.

METHODS

Scrutinizing the data so far appeared in literature on this topic, we have found only few studies evaluating the autoimmune pattern in affected patients, searching in particular for antipituitary and antihypothalamus autoantibodies (APA and AHA, respectively) by simple indirect immunofluorescence.

RESULTS

The presence of APA and/or AHA at high titers was associated with an increased risk of onset/persistence of PTHP.

CONCLUSIONS

HPA seems to contribute to TBI-induced pituitary damage and related PTHP. However, further prospective studies in a larger cohort of patients are needed to define etiopathogenic and diagnostic role of APA/AHA in development of post-traumatic hypothalamic/pituitary dysfunctions after a TBI.

Prophylactic postnatal corticosteroids: Early hydrocortisone

Inflammation is a key contributor to the pathogenesis of bronchopulmonary dysplasia (BPD) in preterm infants, and cortisol plays a central role in controlling inflammation. Insufficient cortisol limits the ability of the sick newborn to handle stress and inhibit pulmonary inflammation. Evidence of lower cortisol and lower response to adrenocorticotropic hormone in infants subsequently developing BPD led to studies of early low-dose hydrocortisone to prevent BPD. Based on four randomised clinical trials enrolling almost 1000 extremely preterm infants, prophylaxis of early adrenal insufficiency with low-dose hydrocortisone significantly decreased BPD and mortality, as well as medical treatment for a patent ductus arteriosus. An increase in late-onset sepsis reported in the most immature infants had no adverse effect on mortality or neurodevelopmental outcomes. There was no increase in gastrointestinal perforation in the absence of indomethacin. The demonstrated beneficial effects of early low-dose hydrocortisone make a strong case for its use in extremely preterm infants at high risk for BPD.

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.

Etomidate as an Induction Agent in Sepsis

Sepsis is a life-threatening response to infection often times requiring endotracheal intubation in critically ill patients. Etomidate is routinely used as an intravenous induction agent to provide sedation and amnesia before placing an endotracheal tube. Although etomidate has many favorable qualities, there is a major concern regarding the predictable adrenal insufficiency that follows its use. Controversy continues to this day as to whether etomidate should be avoided in the setting of sepsis or septic shock.

Neonatal adrenal findings: significance and diagnostic approach. Description of two cases

Abnormal adrenal findings such as hemorrhage or calcifications in the neonate can stem from a variety of etiologies. Clinical presentation can vary significantly based on the degree of hemorrhage or the associated condition. Thorough work‐up is important to rule out critical underlying conditions as well as adrenal insufficiency.

Acute-Onset Panhypopituitarism Nearly Missed by Initial Cosyntropin Testing

Introduction

Diagnosis of adrenal crisis and panhypopituitarism in patients with septic shock is difficult but crucial for outcome.

Case

A 66-year-old woman with metastasized breast cancer presented to the ED with respiratory insufficiency and septic shock after a 2-day history of the flu. After transfer to the ICU, corticosteroids were started in addition to antibiotics, as the patient was vasopressor-nonresponsive. Diabetes insipidus was diagnosed due to polyuria and treated with 4 mg desmopressin. Thereafter, norepinephrine could be tapered rapidly. On day 2, basal cortisol was 136 nmol/L with an increase to 579 nmol/L in low-dose cosyntropin testing. Polyuria had not developed again. Therefore, corticosteroids were stopped. On day 3, the patient developed again nausea, vomiting, and polyuria. Adrenal crisis and diabetes insipidus were postulated. Corticosteroids and desmopressin were restarted. Further testing confirmed panhypopituitarism. MRI showed a new sellar metastasis. After 2 weeks, stimulated cortisol in cosyntropin testing reached only 219 nmol/l, confirming adrenal insufficiency.

Discussion

The time course showed that the adrenal glands took 2 weeks to atrophy after loss of pituitary ACTH secretion. Therefore, a misleading result of the cosyntropin test in the initial phase with low basal cortisol and allegedly normal response to exogenous ACTH may be seen. Cosyntropin testing in the critically ill should be interpreted with caution and in the corresponding clinical setting.

Enhanced cosyntropin stimulation test performance enabled by electronic medical record

PURPOSE

To improve performance of the cosyntropin stimulation test (CST) used for diagnosis of adrenal-cortisol insufficiency by implementing an electronic medical record (EMR) system protocol.

METHODS

We implemented a SmartForm protocol of the validated CST in our EMR system (CS-Link™, EPIC) system and compared medical staff test performance before and after protocol implementation.

RESULTS

Correct performance of the CST improved significantly after EMR implementation. The number of correctly performed CSTs increased from 16.1 % before to 53.5 % after implementation (p < 0.0001) while those performed incorrectly and were uninterpretable decreased from 36.2 to 7.1 % (p < 0.0001). This performance improvement result in a calculated cost savings of $50,414 for every 100 tests performed.

CONCLUSIONS

The EMR system is useful for guiding medical staff to accurately perform the CST, reduce the number of wasted tests, and maximize staff time and resources.

Evaluation of peripheral blood CD34+ cell count in the acute phase of traumatic brain injury and chest trauma

AIM

To determine the impact of traumatic brain injury (TBI) and chest trauma (CT) on the number of peripheral blood (PB) stem cells in affected patients in comparison to normal controls. Additionally, the aim was to determine the relationship between CD34+ cell counts and TBI-induced hypothalamus-pituitary-adrenal axis dysfunction in the acute phase of trauma.

PATIENTS AND METHOD

Thirty patients with TBI, 12 patients with CT and 53 healthy subjects were included in the study.

RESULTS

CD34+ cell counts within the first 24-48 hours of TBI were found to be lower than those obtained on the 7(th) day of TBI and those in the healthy controls. CD34+ cell counts obtained on the 2(nd) day of CT were lower than those in the healthy group, but did not differ from those measured on the 7(th) day of CT. There was no correlation between CD34+ cell counts and serum total cortisol (STC) levels on the 2(nd) and 7(th) days in the TBI or CT groups.

CONCLUSION

An increase in CD34+ cell counts as observed on the 7(th) day in both TBI and CT groups suggested that CD34 changes were not specific to TBI. Moreover, this study showed for the first time that CD34 response was not affected by changes in cortisol levels induced by TBI and severity of TBI.

GH and Pituitary Hormone Alterations After Traumatic Brain Injury

Traumatic brain injury (TBI) is a crucially important public health problem around the world, which gives rise to increased mortality and is the leading cause of physical and psychological disability in young adults, in particular. Pituitary dysfunction due to TBI was first described 95 years ago. However, until recently, only a few papers have been published in the literature and for this reason, TBI-induced hypopituitarism has been neglected for a long time. Recent studies have revealed that TBI is one of the leading causes of hypopituitarism. TBI which causes hypopituitarism may be characterized by a single head injury such as from a traffic accident or by chronic repetitive head trauma as seen in combative sports including boxing, kickboxing, and football. Vascular damage, hypoxic insult, direct trauma, genetic predisposition, autoimmunity, and neuroinflammatory changes may have a role in the development of hypopituitarism after TBI. Because of the exceptional structure of the hypothalamo-pituitary vasculature and the special anatomic location of anterior pituitary cells, GH is the most commonly lost hormone after TBI, and the frequency of isolated GHD is considerably high. TBI-induced pituitary dysfunction remains undiagnosed and therefore untreated in most patients because of the nonspecific and subtle clinical manifestations of hypopituitarism. Treatment of TBI-induced hypopituitarism depends on the deficient anterior pituitary hormones. GH replacement therapy has some beneficial effects on metabolic parameters and neurocognitive dysfunction. Patients with TBI without neuroendocrine changes and those with TBI-induced hypopituitarism share the same clinical manifestations, such as attention deficits, impulsion impairment, depression, sleep abnormalities, and cognitive disorders. For this reason, TBI-induced hypopituitarism may be neglected in TBI victims and it would be expected that underlying hypopituitarism would aggravate the clinical picture of TBI itself. Therefore, the diagnosis and treatment of unrecognized hypopituitarism due to TBI are very important not only to decrease morbidity and mortality due to hypopituitarism but also to alleviate the chronic sequelae caused by TBI.

Pituitary and/or hypothalamic dysfunction following moderate to severe traumatic brain injury: Current perspectives

There is an increasing deliberation regarding hypopituitarism following traumatic brain injury (TBI) and recent data have suggested that pituitary dysfunction is very common among survivors of patients having moderate-severe TBI which may evolve or resolve over time. Due to high prevalence of pituitary dysfunction after moderate-severe TBI and its association with increased morbidity and poor recovery and the fact that it can be easily treated with hormone replacement, it has been suggested that early detection and treatment is necessary to prevent long-term neurological consequences. The cause of pituitary dysfunction after TBI is still not well understood, but evidence suggests few possible primary and secondary causes. Results of recent studies focusing on the incidence of hypopituitarism in the acute and chronic phases after TBI are varied in terms of severity and time of occurrence. Although the literature available does not show consistent values and there is difference in study parameters and diagnostic tests used, it is clear that pituitary dysfunction is very common after moderate to severe TBI and patients should be carefully monitored. The exact timing of development cannot be predicted but has suggested regular assessment of pituitary function up to 1 year after TBI. In this narrative review, we aim to explore the current evidence available regarding the incidence of pituitary dysfunction in acute and chronic phase post-TBI and recommendations for screening and follow-up in these patients. We will also focus light over areas in this field worthy of further investigation.

Pituitary dysfunction after traumatic brain injury: a clinical and pathophysiological approach

Traumatic brain injury (TBI) is a growing public health problem worldwide and is a leading cause of death and disability. The causes of TBI include motor vehicle accidents, which are the most common cause, falls, acts of violence, sports-related head traumas, and war accidents including blast-related brain injuries. Recently, pituitary dysfunction has also been described in boxers and kickboxers. Neuroendocrine dysfunction due to TBI was described for the first time in 1918. Only case reports and small case series were reported until 2000, but since then pituitary function in TBI victims has been investigated in more detail. The frequency of hypopituitarism after TBI varies widely among different studies (15-50% of the patients with TBI in most studies). The estimates of persistent hypopituitarism decrease to 12% if repeated testing is applied. GH is the most common hormone lost after TBI, followed by ACTH, gonadotropins (FSH and LH), and TSH. The underlying mechanisms responsible for pituitary dysfunction after TBI are not entirely clear; however, recent studies have shown that genetic predisposition and autoimmunity may have a role. Hypopituitarism after TBI may have a negative impact on the pace or degree of functional recovery and cognition. What is not clear is whether treatment of hypopituitarism has a beneficial effect on specific function. In this review, the current data related to anterior pituitary dysfunction after TBI in adult patients are updated, and guidelines for the diagnosis, follow-up strategies, and therapeutic approaches are reported.

Pituitary dysfunction following traumatic brain injury: clinical perspectives

Traumatic brain injury (TBI) is a well recognized public health problem worldwide. TBI has previously been considered as a rare cause of hypopituitarism, but an increased prevalence of neuroendocrine dysfunction in patients with TBI has been reported during the last 15 years in most of the retrospective and prospective studies. Based on data in the current literature, approximately 15%-20% of TBI patients develop chronic hypopituitarism, which clearly suggests that TBI-induced hypopituitarism is frequent in contrast with previous assumptions. This review summarizes the current data on TBI-induced hypopituitarism and briefly discusses some clinical perspectives on post-traumatic anterior pituitary hormone deficiency.

Longitudinal assessment of adrenal function in the early and prolonged phases of critical illness in septic patients: relations to cytokine levels and outcome

CONTEXT

Adrenal dysfunction remains a controversial issue in critical care. The long-stay intensive care unit (ICU) population may be at increased risk of adrenal insufficiency.

OBJECTIVE

We aimed to determine whether adrenal dysfunction develops during the course of sepsis.

DESIGN

This is a prospective observational longitudinal study.

SETTING

The study was conducted in the ICU of a secondary/tertiary care hospital.

PATIENTS

We studied 51 consecutive mechanically ventilated patients with sepsis.

INTERVENTION

We measured cortisol, ACTH, cortisol-binding globulin, cytokines, and cortisol 30 minutes after 1 μg ACTH(1-24), upon sepsis diagnosis and every 3 to 4 days, until Day 30 or until recovery or death.

MAIN OUTCOME MEASURES

We looked for changes in baseline and stimulated cortisol levels and its relationship to ACTH levels, sepsis severity or survival.

RESULTS

Baseline and stimulated cortisol levels did not vary significantly. Septic patients with shock had higher baseline (20 ± 6 vs 17 ± 5 μg/dL, P = .03) and stimulated cortisol levels (26 ± 5 vs 23 ± 6 μg/dL, P = .04), compared with those without shock. On Day 1, ACTH levels could not predict cortisol levels (R(2) = 0.06, P = .08). ACTH levels increased significantly after Day 10 and, at this time point, they related to cortisol levels (R(2) = 0.35, P < .001). Development of septic shock, or resolution from it, was not associated with changes in baseline, stimulated cortisol levels, or the cortisol increment. There was much inpatient variability in the diagnosis of adrenal dysfunction at different time points.

CONCLUSIONS

Total cortisol levels relate both to the severity and outcome of sepsis and remain fairly unchanged during the course of illness. Initially, cortisol levels are largely ACTH independent, whereas ACTH increases and correlates with cortisol levels later on. Adrenal dysfunction does not seem to be a major problem during the prolonged phase of sepsis. Although not significant, the variation in cortisol levels may be such that classification of patients varies, questioning the utility of arbitrary cut-offs to define adrenal dysfunction in septic patients.

Clinical factors associated with biochemical adrenal-cortisol insufficiency in hospitalized patients

BACKGROUND

Diagnosis of adrenal-cortisol insufficiency is often misleading in hospitalized patients, as clinical and biochemical features overlap with comorbidities. We analyzed clinical determinants associated with a biochemical diagnosis of adrenal-cortisol insufficiency in non-intensive care unit (ICU) hospitalized patients.

METHODS

In a retrospective cohort study we reviewed 4668 inpatients with random morning cortisol levels ≤15 μg/dL hospitalized in our center between 2003 and 2010. Using serum cortisol threshold level of 18 μg/dL 30 or 60 minutes after Cortrosyn (250 μg; Amphastar Pharmaceuticals, Inc., Rancho Cucamonga, Calif) injection to define biochemical adrenal-cortisol status, we characterized and compared insufficient (n = 108, serum cortisol ≤18 μg/dL) and sufficient (n = 394; serum cortisol >18 μg/dL) non-ICU hospitalized patients.

RESULTS

Commonly reported clinical and routine biochemical adrenal-cortisol insufficiency features were similar between insufficient and sufficient inpatients. Biochemical adrenal-cortisol insufficiency was associated with increased frequency of liver disease, specifically hepatitis C (P = .01) and prior orthotopic liver transplantation (P <.001), human immunodeficiency virus (HIV; P = .005), and reported pre-existing male hypogonadism (P <.001), as compared with the biochemical adrenal-cortisol sufficiency group. Forty percent of insufficient inpatients were not treated with glucocorticoids after diagnosis. Multivariable logistic analysis demonstrated that inpatients with higher cortisol levels (P = .0001) and higher diastolic blood pressure (P = .05), and females (P = .009) were more likely not to be treated, while those with previous short-term glucocorticoid treatment (P = .002), other coexisting endocrine diseases (P = .005), or who received an in-hospital endocrinology consultation (P <.0001), were more likely to be replaced with glucocorticoids.

CONCLUSIONS

Commonly reported adrenal-cortisol insufficiency features do not reliably identify hospitalized patients biochemically confirmed to have this disorder. Comorbidities including hepatitis C, prior orthotopic liver transplantation, HIV, and reported pre-existing male hypogonadism may help identify hospitalized non-ICU patients for more rigorous adrenal insufficiency assessment.

Brain death in ICU patients: Clinical significance of endocrine changes

Numerous studies have been carried out among patients admitted in intensive care unit (ICU) having primary endocrine pathology, endocrine manifestations of systemic diseases or post-endocrine tissue surgery. However, minimal literary evidence is available highlighting the endocrine changes occurring during brain death in critically ill patients. A precise and timely diagnosis of brain death is required to convey the relatives about the prognosis and also to possibly plan for organ retrieval for transplantation purposes. The diagnosis of this condition as of today remains largely a clinical one. Brain death is associated with a multitude of endocrinological alterations which are yet to be completely unraveled and understood. Evaluating these endocrinological modifications lends us an added vista to add to the existing clinical parameters which might help us to confirm the diagnosis of brain death with a higher degree of precision. Moreover, since the efficacy of hormone replacement therapy to benefit in organ retrieval remains yet unproven, newer diagnostic modalities and research studies are definitely called for to strategize the optimal dosage and duration of such therapies.

Reduced glucocorticoid receptor protein expression in children with critical illness

BACKGROUND/AIMS

The diagnostic criteria for critical illness-related corticoid insufficiency (CIRCI) are not well established, particularly for children. In addition to alterations in adrenal function, cellular resistance to glucocorticoid action could contribute to CIRCI due to alterations in the functioning of the intracellular receptor protein for corticosteroids, the glucocorticoid receptor (GR).

METHODS

We have therefore undertaken a pilot, prospective study to assess whether cellular GR activity can be measured in peripheral blood mononuclear cells (PBMCs) from critically ill children.

RESULTS

Total and cytoplasmic, but not nuclear GR levels were significantly lower in PBMCs from critically ill children (i.e. sepsis/septic shock and traumatic brain injury) compared to healthy controls . While total cortisol concentrations did not differ between test groups, salivary and serum-free cortisol concentrations were significantly greater in both groups of children with critical illness. Cortisol-binding globulin levels were significantly lower in patients with sepsis/septic shock.

CONCLUSIONS

The lower total and cytoplasmic receptor levels in critically ill children suggest that the GR-mediated response to exogenous glucocorticoid therapy may be limited. However, the nuclear transport of GR in critically ill patients suggests that residual receptors in these patients retain functionality and may be accessible to therapeutic treatments that maximize their activity.

Is prolonged low-dose glucocorticoid treatment beneficial in community-acquired pneumonia?

Community-acquired pneumonia (CAP) has a significant impact on public health in terms of short-term and long-term morbidity and mortality. Irrespective of microbiological etiology, the host's inability to fully downregulate systemic inflammation is the dominant pathogenetic process contributing to acute and long-term morbidity and mortality in CAP. Glucocorticoids are the natural regulators of inflammation, and their production increases during infection. There is consistent evidence that downregulation of systemic inflammation with prolonged low-dose glucocorticoid treatment in patients with severe sepsis and acute respiratory distress syndrome improves cardiovascular and pulmonary organ physiology. A recent meta-analysis of pooled controlled small trials (n = 970) of patients admitted with CAP found improved short-term mortality in the subgroup with severe CAP and/or receiving >5 days of glucocorticoid treatment. We have expanded on this meta-analysis by including patients with CAP recruited in trials investigating prolonged low-dose glucocorticoid treatment in septic shock and/or early acute respiratory distress syndrome (n = 1,206). Our findings confirm a survival advantage for severe CAP (RR 0.66, 95% confidence interval 0.51-0.84; p = .001). A large randomized trial is in progress to confirm the aggregate findings of these small trials and to evaluate the long-term effect of this low-cost treatment.

[Addison's disease]

The clinical signs and symptoms of primary adrenal insufficiency are unspecific often causing a delayed diagnosis or even misdiagnosis. In the diagnostic work-up the short synacthen test is regarded as the gold standard. Hydrocortisone and fludrocortisone are the preferred therapy for Addison's disease. The management and surveillance of therapy requires experience and several aspects need to be followed to prevent side effects which might occur due to overtreatment or undertreatment. Very important aspects in therapy are the repeated teaching of the patient and relatives, the issuing of an emergency steroid card and the prescription of a glucocorticoid emergency set. Acute adrenal failure (adrenal crisis), which might be the first manifestation of adrenal insufficiency, is a life-threatening situation requiring immediate glucocorticoid administration and fluid substitution. The most common causes for an adrenal crisis are gastrointestinal infections and fever and discontinuation of glucocorticoid therapy. This article gives an up-to-date overview of diagnostic and therapeutic aspects of Addison's disease.

Anesthesia advanced circulatory life support

PURPOSE

The constellation of advanced cardiac life support (ACLS) events, such as gas embolism, local anesthetic overdose, and spinal bradycardia, in the perioperative setting differs from events in the pre-hospital arena. As a result, modification of traditional ACLS protocols allows for more specific etiology-based resuscitation.

PRINCIPAL FINDINGS

Perioperative arrests are both uncommon and heterogeneous and have not been described or studied to the same extent as cardiac arrest in the community. These crises are usually witnessed, frequently anticipated, and involve a rescuer physician with knowledge of the patient's comorbidities and coexisting anesthetic or surgically related pathophysiology. When the health care provider identifies the probable cause of arrest, the practitioner has the ability to initiate medical management rapidly.

CONCLUSIONS

Recommendations for management must be predicated on expert opinion and physiological understanding rather than on the standards currently being used in the generation of ACLS protocols in the community. Adapting ACLS algorithms and considering the differential diagnoses of these perioperative events may prevent cardiac arrest.

Evidence-based neonatal pharmacotherapy: postnatal corticosteroids

Corticosteroids are used in the neonatal intensive care unit primarily to treat two conditions: bronchopulmonary dysplasia (BPD) and hypotension (cardiovascular insufficiency). Historically, high-dose dexamethasone was used for BPD, but its use was later associated with adverse neurodevelopmental outcomes and decreased substantially. Data from randomized controlled trials regarding efficacy and safety of lower-dose dexamethasone therapy are insufficient to recommend its use. Hydrocortisone may be an alternative to dexamethasone, but again data are insufficient to support use. Hydrocortisone therapy is increasingly used to treat hypotension in critically ill newborns; however, the outcomes of this therapy must be evaluated in randomized trials.

Glucocorticoids in the treatment of acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is characterized by local inflammation and an intense systemic inflammatory reaction. Glucocorticoid administration has been suggested due to their anti-inflammatory properties. However, results from the initial studies of glucocorticoids in ARDS, which evaluated high-dose and short-term treatments, were negative. More recent studies have evaluated the effect of lower doses of glucocorticoids administered over longer periods, but the results thus far have been inconclusive.

Glucocorticoid treatment in acute lung injury and acute respiratory distress syndrome

Experimental and clinical evidence show a strong association between dysregulated systemic inflammation and progression of acute respiratory distress syndrome (ARDS). This article reviews eight controlled studies evaluating corticosteroid treatment initiated before day 14 of ARDS. Available data provide a consistent strong level of evidence for improving outcomes. Treatment was also associated with a markedly reduced risk of death. This low-cost highly effective therapy is well-known, and has a low-risk profile when secondary prevention measures are implemented. The authors recommend prolonged methylprednisolone at 1 mg/kg/d initially in early ARDS, increasing to 2 mg/kg/d after 7 to 9 days of no improvement.

Pathophysiology of acute respiratory distress syndrome. Glucocorticoid receptor-mediated regulation of inflammation and response to prolonged glucocorticoid treatment

Based on molecular mechanisms and physiologic data, a strong association has been established between dysregulated systemic inflammation and progression of ARDS. In ARDS patients, glucocorticoid receptor-mediated down-regulation of systemic inflammation is essential to restore homeostasis, decrease morbidity and improve survival and can be significantly enhanced with prolonged low-to-moderate dose glucocorticoid treatment. A large body of evidence supports a strong association between prolonged glucocorticoid treatment-induced down-regulation of the inflammatory response and improvement in pulmonary and extrapulmonary physiology. The balance of the available data from controlled trials provides consistent strong level of evidence (grade 1B) for improving patient-centered outcomes. The sizable increase in mechanical ventilation-free days (weighted mean difference, 6.58 days; 95% CI, 2.93 -10.23; P<0.001) and ICU-free days (weighted mean difference, 7.02 days; 95% CI, 3.20-10.85; P<0.001) by day 28 is superior to any investigated intervention in ARDS. The largest meta-analysis on the subject concluded that treatment was associated with a significant risk reduction (RR=0.62, 95% CI: 0.43-0.91; P=0.01) in mortality and that the in-hospital number needed to treat to save one life was 4 (95% CI 2.4-10). The balance of the available data, however, originates from small controlled trials with a moderate degree of heterogeneity and provides weak evidence (grade 2B) for a survival benefit. Treatment decisions involve a tradeoff between benefits and risks, as well as costs. This low cost highly effective therapy is familiar to every physician and has a low risk profile when secondary prevention measures are implemented.

Overview of the endocrine response to critical illness: how to measure it and when to treat

The assessment and manipulation of the endocrine system in patients with critical illness is one of the most complex and controversial areas in endocrinology. Severe acute illness causes dramatic changes in most endocrine systems. This can lead to considerable difficulty in recognising pre-existing endocrine disorders in severely ill patients. Critical care itself might also induce types of endocrine dysfunction not seen outside the critical care unit. It is important to clarify whether or not such endocrine dysfunction occurs. Where it does occur it is also important to determine whether endocrine intervention is useful in improving outcome. There is also the issue of whether endocrine manipulation in critically ill patients without endocrine dysfunction could benefit from endocrine intervention, e.g. to improve haemodynamics or reverse a catabolic state. This review will discuss some of these contentious issues. It will highlight how endocrine assessment of a patient with critical illness differs from that in other types of patient. It will emphasise the added need to place the biochemical assessment and its interpretation in the context of the patients underlying condition.

Endocrine changes in brain death and transplantation

Following brain death (BD) many hormonal changes occur. These include an increase and then a fall in the levels of circulating catecholamines, reduced levels of anti-diuretic hormone and cortisol as well as alterations in the hypothalamic-pituitary thyroid axis consistent with the non-thyroidal illness syndrome. In an era when the numbers of potential recipients listed for transplantation are greater than the number of donors, with an increasing donor age, a detailed knowledge of the endocrine changes and pathophysiological consequences of these is essential to optimise the management of the brain-stem dead organ donor. There still remains significant debate as to whether hormone replacement therapy to correct the observed changes is beneficial.

A Comparative Effectiveness Analysis of Alternative Strategies to Assess Hypothalamic-Pituitary-Adrenal Axis Function After Microsurgical Resection of Pituitary Tumors

BACKGROUND:

Observational methods can be used in conjunction with the comparative effectiveness research (CER) paradigm to inform decisions between alternative patient management strategies in real-world clinical settings.

OBJECTIVE:

To present a brief review of current observational research regarding 3 strategies for predicting normal hypothalamic-pituitary-adrenal (HPA) axis function after surgical resection of pituitary tumors and to apply the CER model to compare these management alternatives.

METHODS:

We designed and conducted 2 prospective observational studies involving 183 patients undergoing microsurgical resection for pituitary tumors. These investigations yielded a comprehensive database comprising longitudinal data from multiple clinical domains. We investigated 3 potential strategies to predict normal postoperative HPA axis function in this cohort, including preoperative adrenocorticotrophic hormone stimulation testing and measurement of serum cortisol levels immediately after surgery or on the first postoperative day. We performed a focused comparative effectiveness review to help inform the decision between the 3 potential clinical management strategies.

RESULTS:

This investigation illustrates the use of observational research methods in conjunction with CER methodology as one means of informing clinical management decisions. Of the 3 strategies for assessing postoperative HPA axis function studied, preoperative and immediate postoperative adrenocorticotrophic hormone stimulation testing had the highest sensitivity, accuracy, and positive predictive value for normal HPA axis function postoperatively. The preoperative strategy was also the most cost-effective approach (12% reduction vs benchmark).

CONCLUSION:

The decision to use any of the 3 strategies outlined requires attention to a specific patient's clinical situation, but this decision may be aided by the results of this CER analysis.

Assessment of the hypothalamic-pituitary-adrenal axis in critical illness

Cortisol is the main corticosteroid secreted from the human adrenal cortex, and it has a crucial role for survival in stressful conditions. An adequate increase in levels of cortisol helps patients to cope with the severity of the disease in the acute phase of critical illness. Either higher or lower than expected cortisol levels were found to be related to increased mortality. Prolonged activation of the hypothalamic-pituitary-adrenal (HPA) axis can result in hypercortisolemia or hypocortisolemia; both can be detrimental to recovery from critical illness. Primary and secondary adrenal insufficiency, relative adrenal insufficiency, tissue resistance to glucocorticoids, adrenocorticotrophic hormone deficiency and immune-mediated inhibition of the HPA axis can be the cause of the impairment of the secretion or action of cortisol in critically ill patients. Recently, some authors offered the term 'critical illness-related corticosteroid insufficiency' to better point out the relative adrenal insufficiency that is seen during critical illness. Patients with critical illness-related corticosteroid insufficiency not only have insufficient circulating cortisol but also have impaired cellular utilization of cortisol. In this article, how adrenal dysfunction presents in critical illness and how appropriate diagnosis and management can be achieved in the critical care setting will be discussed.

Adrenal function in newborns undergoing surgery

OBJECTIVE

To measure cortisol, adrenocorticotropic hormone (ACTH)-stimulated cortisol and ACTH values in the newborn intensive care unit-admitted newborn infants within 48 h before surgery and to describe the relationship of these values to measures of clinical illness before and after surgery.

STUDY DESIGN

In this prospective observational study, we measured baseline and ACTH-stimulated cortisol concentrations within 48 h before surgery in newborn infants <44 weeks postmenstrual age and examined the relationship of these values to measures of illness severity both before and after surgery, including the score for neonatal acute physiology (SNAP) and use of vasopressors. ACTH concentrations were measured in a subset of the infants.

RESULT

Twenty-five infants were enrolled and had median (25th to 75th percentile) baseline and ACTH-stimulated cortisol values of 7.1 (3.5 to 11.1) and 40.4 mcg per 100 ml (22.6 to 50.6). Preterm infants had significantly lower ACTH-stimulated cortisol values (median 21.6 vs 44.7 mcg per 100 ml). There was no correlation between any of these values and either the presurgical or postsurgical measures of illness severity, nor the increase in SNAP after surgery. Infants receiving vasopressors perioperatively had lower median ACTH-stimulated cortisol values (22.6 vs 44.7 mcg per 100 ml).

CONCLUSION

Presurgical cortisol values do not predict clinical response to surgical stress as measured by severity of illness scores but lower values were associated with vasopressor therapy. Further investigation would be required to determine how cortisol values are related to outcome and whether perioperative glucocorticoid supplementation would be beneficial in this population.

Immediate postoperative cortisol levels accurately predict postoperative hypothalamic-pituitary-adrenal axis function after transsphenoidal surgery for pituitary tumors

Accurate assessment of the hypothalamic-pituitary-adrenal (HPA) axis is critical for the appropriate management of patients with pituitary adenoma after transsphenoidal surgery. We examine the role of immediate postoperative cortisol levels to assess hypothalamic-pituitary-adrenal axis (HPA) axis function post-operatively. We performed preoperative cortrosyn stimulation test (CST) and measured immediate postoperative serum cortisol levels in 100 patients undergoing 104 transsphenoidal surgeries. These results were compared to those of the CST at 4-6 weeks postoperatively, which served as a measure of HPA axis function. The ability of immediate postoperative, day of surgery (DOS) cortisol levels to predict normal HPA axis function was determined using standard predictive analytic methods and confusion matrix calculations. We found that postoperative, DOS cortisol level > or =15 microg/dL is a sensitive and accurate predictors of normal postoperative HPA axis function, with a sensitivity of 98%, an accuracy of 97%, and a positive predictive value of 99%. Our data suggest that an immediate, postoperative, DOS cortisol level > or =15 microg/dL predicts distant, normal, post-operative HPA axis function following transsphenoidal surgery.

Outcomes of etomidate in severe sepsis and septic shock

BACKGROUND

The use of single-dose etomidate to facilitate intubation in critically ill patients has recently been debated given its suppression of steroidogenesis with possible resultant adverse outcomes. Our objective was to assess the effects of single-dose etomidate used during rapid-sequence intubation (RSI) on various measures of outcome, such as mortality, vasopressor use, corticosteroid use, ICU length of stay (ICU-LOS), and number of ventilator days.

METHODS

A retrospective 18-month cohort study was performed in a multidisciplinary ICU of an academic tertiary care institution. Consecutive patients with severe sepsis or septic shock who were intubated and mechanically ventilated were identified and grouped as having received single-dose etomidate during intubation or not. Hospital mortality, ICU length of stay, number of ventilator days, corticosteroid use, vasopressor use, and demographic and clinical variables were recorded.

RESULTS

Two hundred twenty-four patients were identified; 113 had received etomidate. The mean Acute Physiology and Chronic Health Evaluation II scores in the etomidate and nonetomidate groups were 21.3 ± 8.1 and 21.9 ± 8.3, respectively (P = .62). The relative risks for mortality and vasopressor use were 0.92 (CI, 0.74-1.14; P = 0.51) and 1.16 (CI, 0.9-1.51; P = .31), respectively, in the etomidate group. There were no significant differences in ICU-LOS (mean, 14 vs 12 days; P = .31) or number of ventilator days (mean, 11 vs 8 days; P = .13) between the etomidate and nonetomidate groups, respectively. The relative risk for corticosteroid use in the etomidate group was 1.34 (CI, 1.11-1.61; P = .003). Multivariate analysis using logistic regression demonstrated no significant association of etomidate with mortality (OR, 0.9; CI, 0.45-1.83; P = .78).

CONCLUSION

Single-dose etomidate used during RSI in critically ill patients with severe sepsis and septic shock was not associated with increased mortality, vasopressor use, ICU-LOS, or number of ventilator days. Patients intubated with etomidate had an increased incidence of subsequent corticosteroid use, with no difference in outcomes.

The 11beta-hydroxysteroid dehydrogenase enzymes--arbiters of the effects of glucocorticoids in synovium and bone

Ever since the first use of cortisone, glucocorticoids have had a controversial role in the treatment of RA. There has been equally controversial research into the possible involvement of endogenous glucocorticoids, and their secretion via the hypothalamic-pituitary-adrenal (HPA) axis, in the development and persistence of inflammatory arthritis. Recently, our understanding of how glucocorticoids act has expanded substantially with the characterization of glucocorticoid-metabolizing enzymes that regulate glucocorticoid action at tissue level. These enzymes, the 11β-hydroxysteroid dehydrogenases, interconvert biologically inactive glucocorticoids such as cortisone and prednisone with their active counterparts, cortisol (hydrocortisone) and prednisolone. Without these enzymes, cortisone and prednisone would be therapeutically useless. Furthermore, in normal individuals, the activities of these enzymes influence the function of other components of the HPA axis. These enzymes are expressed in human synovial tissue and bone and have been implicated in the control of synovial inflammation, the development of periarticular bone loss and the sensitivity of bone to therapeutic glucocorticoids. This article reviews recent findings in this area that highlight the role of these enzymes in rheumatic diseases.

Updating the evidence for the role of corticosteroids in severe sepsis and septic shock: a Bayesian meta-analytic perspective

Introduction

Current low (stress) dose corticosteroid regimens may have therapeutic advantage in severe sepsis and septic shock despite conflicting results from two landmark randomised controlled trials (RCT). We systematically reviewed the efficacy of corticosteroid therapy in severe sepsis and septic shock.

Methods

RCTs were identified (1950-September 2008) by multiple data-base electronic search (MEDLINE via OVID, OVID PreMedline, OVID Embase, Cochrane Central Register of Controlled trials, Cochrane database of systematic reviews, Health Technology Assessment Database and Database of Abstracts of Reviews of Effects) and hand search of references, reviews and scientific society proceedings. Three investigators independently assessed trial inclusion and data extraction into standardised forms; differences resolved by consensus.

Results

Corticosteroid efficacy, compared with control, for hospital-mortality, proportion of patients experiencing shock-resolution, and infective and non-infective complications was assessed using Bayesian random-effects models; expressed as odds ratio (OR, (95% credible-interval)). Bayesian outcome probabilities were calculated as the probability (P) that OR ≥1. Fourteen RCTs were identified. High-dose (>1000 mg hydrocortisone (equivalent) per day) corticosteroid trials were associated with a null (n = 5; OR 0.91(0.31-1.25)) or higher (n = 4, OR 1.46(0.73-2.16), outlier excluded) mortality probability (P = 42.0% and 89.3%, respectively). Low-dose trials (<1000 mg hydrocortisone per day) were associated with a lower (n = 9, OR 0.80(0.40-1.39); n = 8 OR 0.71(0.37-1.10), outlier excluded) mortality probability (20.4% and 5.8%, respectively). OR for shock-resolution was increased in the low dose trials (n = 7; OR 1.20(1.07-4.55); P = 98.2%). Patient responsiveness to corticotrophin stimulation was non-determinant. A high probability of risk-related treatment efficacy (decrease in log-odds mortality with increased control arm risk) was identified by metaregression in the low dose trials (n = 9, slope coefficient -0.49(-1.14, 0.27); P = 92.2%). Odds of complications were not increased with corticosteroids.

Conclusions

Although a null effect for mortality treatment efficacy of low dose corticosteroid therapy in severe sepsis and septic shock was not excluded, there remained a high probability of treatment efficacy, more so with outlier exclusion. Similarly, although a null effect was not excluded, advantageous effects of low dose steroids had a high probability of dependence upon patient underlying risk. Low dose steroid efficacy was not demonstrated in corticotrophin non-responders. Further large-scale trials appear mandated.

Adrenal gland and bone

The adrenal gland synthesizes steroid hormones from the adrenal cortex and catecholamines from the adrenal medulla. Both cortisol and adrenal androgens can have powerful effects on bone. The overproduction of cortisol in Cushing's disease leads to a dramatic reduction in bone density and an increase risk of fracture. Overproduction of adrenal androgens in congenital adrenal hyperplasia (CAH) leads to marked changes in bone growth and development with early growth acceleration but ultimately a significant reduction in final adult height. The role of more physiological levels of glucocorticoids and androgens on bone metabolism is less clear. Cortisol levels measured in elderly individuals show a weak correlation with measures of bone density and change in bone density over time with a high cortisol level associated with lower bone density and more rapid bone loss. Cortisol levels and the dynamics of cortisol secretion change with age which could also explain some age related changes in bone physiology. It is also now clear that adrenal steroids can be metabolized within bone tissue itself. Local synthesis of cortisol within bone from its inactive precursor cortisone has been demonstrated and the amount of cortisol produced within osteoblasts appears to increase with age. With regard to adrenal androgens there is a dramatic reduction in levels with aging and several studies have examined the impact that restoration of these levels back to those seen in younger individuals has on bone health. Most of these studies show small positive effects in women, not men, but the skeletal sites where benefits are seen varies from study to study.

Prolonged glucocorticoid treatment and secondary prevention in acute respiratory distress syndrome

Experimental and clinical evidence has demonstrated a strong association between dysregulated systemic inflammation and progression of acute respiratory distress syndrome (ARDS). In ARDS, glucocorticoid receptor-mediated downregulation of inflammation is essential to restore homeostasis and decrease morbidity and mortality. We review the findings of eight controlled studies (n = 569) evaluating treatment initiated before day 14 of ARDS. These trials consistently reported that treatment-induced reduction in systemic inflammation was associated with a significant improvement in ratio of partial arterial oxygen tension to fraction of inspired oxygen, and reductions in multiple organ dysfunction score, duration of mechanical ventilation and intensive care unit length of stay. Treatment was also associated with a marked reduction in the risk of death (relative risk: 0.68; 95% CI: 0.56-0.81; p < 0.001) and a sizable increase in mechanical ventilation-free days (weighted mean difference: 6.58 days; 95% CI: 2.93-10.23; p < 0.001); and intensive care unit-free days (weighted mean difference: 7.02 days; 95% CI: 3.20-10.85; p < 0.001). We recommend that prolonged methylprednisolone treatment, at an initial dose of 1 mg/kg/day in early ARDS and 2 mg/kg/day in unresolving ARDS, be delivered as an infusion to avoid glycemic variability, and that infection surveillance be strictly implemented to identify infections in the absence of fever.

Adjunctive therapies in severe sepsis and septic shock: current place of steroids

For more than five decades, the use of corticosteroids as an adjunctive therapy to treat severe sepsis and septic shock has incited consistent debate. Negative results of the Corticosteroid Therapy of Septic Shock (CORTICUS) study evoked a revision of Surviving Sepsis Campaign guidelines suggesting a more restricted use of low-dose hydrocortisone only in patients with severe septic shock. Hemodynamic improvement by low-dose steroids was evident and independent from adrenal insufficiency, but did not improve survival. The roles of cortisol measurement and adrenal function tests for treatment decisions have been questioned. An international task force introduced the concept of critical illness-related corticosteroid insufficiency, which challenges the predominant role of adrenal dysfunction and underscores sustained inflammation due to tissue steroid resistance. Whether moderate steroid doses induce superinfections and muscle weakness is unclear. This article reviews recent publications, actual recommendations, ongoing discussions, and future perspectives.

A prospective multicenter study of adrenal function in critically ill children

RATIONALE

Adrenal insufficiency is a clinical condition associated with fluid- and catecholamine-resistant hypotension.

OBJECTIVES

The objectives of this study were to determine the prevalence of adrenal insufficiency, risk factors and potential mechanisms for its development, and its association with clinically important outcomes in critically ill children.

METHODS

A prospective, cohort study was conducted from 2005 to 2008 in seven tertiary-care, pediatric intensive care units in Canada on patients up to 17 years of age with existing vascular access. Adrenocorticotropic hormone stimulation tests (1 microg) were performed and adrenocorticotropic hormone levels measured in all participants.

MEASUREMENTS AND MAIN RESULTS

A total of 381 patients had adrenal testing on admission. The prevalence of adrenal insufficiency was 30.2% (95% confidence interval, 25.9-35.1). Patients with adrenal insufficiency had higher baseline cortisol levels (28.6 microg/dl vs. 16.7 microg/dl, P < 0.001) and were significantly older (11.5 yr vs. 2.3 yr, P < 0.001) than those without adrenal insufficiency. Adrenal insufficiency was associated with an increased need for catecholamines (P < 0.001) and more fluid boluses (P = 0.026). The sensitivity and specificity of the low-dose adrenocorticotropic hormone stimulation test were 100% and 84%, respectively.

CONCLUSIONS

Adrenal insufficiency occurs in many disease conditions in critically ill children and is associated with an increased use of catecholamines and fluid boluses. It is likely multifactorial in etiology and is associated with high baseline cortisol levels. Further research is necessary to determine which of these critically ill children are truly cortisol deficient before any treatment recommendations can be made.