Hydrocortisone increases the sensitivity to α1-adrenoceptor stimulation in humans following hemorrhagic shock*

The Chemokine (C-C Motif) Receptor 2 Antagonist INCB3284 Reduces Fluid Requirements and Protects From Hemodynamic Decompensation During Resuscitation From Hemorrhagic Shock

Clinical correlations suggest that systemic chemokine (C-C motif) ligand (CCL) 2 release may contribute to blood pressure regulation and the development of hemodynamic instability during the early inflammatory response to traumatic-hemorrhagic shock. Thus, we investigated whether blockade of the principal CCL2 receptor chemokine (C-C motif) receptor (CCR) 2 affects blood pressure in normal animals, and hemodynamics and resuscitation fluid requirements in hemorrhagic shock models.

Insight into the Role of Psychological Factors in Oral Mucosa Diseases

With the development of psychology and medicine, more and more diseases have found their psychological origins and associations, especially ulceration and other mucosal injuries, within the digestive system. However, the association of psychological factors with lesions of the oral mucosa, including oral squamous cell carcinoma (OSCC), burning mouth syndrome (BMS), and recurrent aphthous stomatitis (RAS), have not been fully characterized. In this review, after introducing the association between psychological and nervous factors and diseases, we provide detailed descriptions of the psychology and nerve fibers involved in the pathology of OSCC, BMS, and RAS, pointing out the underlying mechanisms and suggesting the clinical indications.

Anesthesia for Trauma Patients

An improved understanding of the pathophysiology of combat trauma has evolved over the past decade and has helped guide the anesthetic care of the trauma patient requiring surgical intervention. Trauma anesthesia begins before patient arrival with warming of the operating room, preparation of anesthetic medications and routine anesthetic machine checks. Induction of anesthesia must account for potential hemodynamic instability and intubation must consider airway trauma. Maintenance of anesthesia is accomplished with anesthetic gas, intravenous infusions or a combination of both. Resuscitation must precede or be ongoing with the maintenance of anesthesia. Blood product transfusion, antibiotic administration, and use of pharmacologic adjuncts (e.g., tranexamic acid, calcium) all occur simultaneously. Ventilatory strategies to mitigate lung injury can be initiated in the operating room, and resuscitation must be effectively transitioned to the intensive care setting after the case. Good communication is vital to efficient patient movement along the continuum of care. The resuscitation that is undertaken before, during and after operative management must incorporate important changes in care of the trauma patient. This Clinical Practice Guideline hopes to provide a template for care of this patient population. It outlines a method of anesthesia that incorporates the induction and maintenance of anesthesia into an ongoing resuscitation during surgery for a trauma patient in extremis.

Hormone Therapy in Trauma Patients

Low-dose hydrocortisone reduces the dose of vasopressors and hospital length of stay; it may also decrease the rate of hospital-acquired pneumonia and time on ventilator. No major side effect was reported, but glycemia and natremia should be monitored. Progesterone did not enhance outcome of trauma patients. A meta-analysis suggested that oxandrolone was associated with shorter length of stay and reduced weight loss. Erythropoietin did not enhance neurologic outcome of traumatic brain-injured patients; such treatment, however, could reduce the mortality in subgroups of patients. This review focuses mainly on glucocorticoids, which are the most extensively investigated treatments in hormone therapy.

Exposure to Stress-Dose Steroids and Lethal Septic Shock After In-Hospital Cardiac Arrest: Individual Patient Data Reanalysis of Two Prior Randomized Clinical Trials that Evaluated the Vasopressin-Steroids-Epinephrine Combination Versus Epinephrine Alone

PURPOSE

Low-dose steroids may reduce the mortality of severely ill patients with septic shock. We sought to determine whether exposure to stress-dose steroids during and/or after cardiopulmonary resuscitation is associated with reduced risk of death due to postresuscitation septic shock.

METHODS

We analyzed pooled, individual patient data from two prior, randomized clinical trials (RCTs). RCTs evaluated vasopressin, steroids, and epinephrine (VSE) during resuscitation and stress-dose steroids after resuscitation in vasopressor-requiring, in-hospital cardiac arrest. In the second RCT, 15 control group patients received open-label, stress-dose steroids. Patients with postresuscitation shock were assigned to a Steroids (n = 118) or No Steroids (n = 73) group according to an "as-treated" principle. We used cumulative incidence competing risks Cox regression to determine cause-specific hazard ratios (CSHRs) for pre-specified predictors of lethal septic shock (primary outcome). In sensitivity analyses, data were analyzed according to the intention-to-treat (ITT) principle (VSE group, n = 103; control group, n = 88).

RESULTS

Lethal septic shock was less likely in Steroids versus No Steroids group, CSHR, 0.40, 95% confidence interval (CI), 0.20-0.82; p = 0.012. ITT analysis yielded similar results: VSE versus Control, CSHR, 0.44, 95% CI, 0.23-0.87; p = 0.019. Adjustment for significant, between-group baseline differences in composite cardiac arrest causes such as "hypotension and/or myocardial ischemia" did not appreciably affect the aforementioned CSHRs.

CONCLUSIONS

In this reanalysis, exposure to stress-dose steroids (primarily in the context of a combined VSE intervention) was associated with lower risk of postresuscitation lethal septic shock.

Low-frequency blood pressure oscillations and inotrope treatment failure in premature infants

The underlying mechanism as to why some hypotensive preterm infants do not respond to inotropic medications remains unclear. For these infants, we hypothesize that impaired vasomotor function is a significant factor and is manifested through a decrease in low-frequency blood pressure variability across regulatory components of vascular tone. Infants born ≤28 wk estimated gestational age underwent prospective recording of mean arterial blood pressure for 72 h after birth. After error correction, root-mean-square spectral power was calculated for each valid 10-min data frame across each of four frequency bands (B1, 0.005-0.0095 Hz; B2, 0.0095-0.02 Hz; B3, 0.02-0.06 Hz; and B4, 0.06-0.16) corresponding to different components of vasomotion control. Forty infants (twenty-nine normotensive control and eleven inotrope-exposed) were included with a mean ± SD estimated gestational age of 25.2 ± 1.6 wk and birth weight 790 ± 211 g. 9.7/11.8 Million (82%) data points were error-free and used for analysis. Spectral power across all frequency bands increased with time, although the magnitude was 20% less in the inotrope-exposed infants. A statistically significant increase in spectral power in response to inotrope initiation was noted across all frequency bands. Infants with robust blood pressure response to inotropes had a greater increase compared with those who had limited or no blood pressure response. In this study, hypotensive infants who require inotropes have decreased low-frequency variability at baseline compared with normotensive infants, which increases after inotrope initiation. Low-frequency spectral power does not change for those with inotrope treatment failure, suggesting dysfunctional regulation of vascular tone as a potential mechanism of treatment failure.NEW & NOTEWORTHY In this study, we examine patterns of low-frequency oscillations in blood pressure variability across regulatory components of vascular tone in normotensive and hypotensive infants exposed to inotropic medications. We found that hypotensive infants who require inotropes have decreased low-frequency variability at baseline, which increases after inotrope initiation. Low-frequency spectral power does not change for those with inotrope treatment failure, suggesting dysfunctional regulation of vascular tone as a potential mechanism of treatment failure.

A review of associated controversies surrounding glucocorticoid use in veterinary emergency and critical care

OBJECTIVE

To review the literature in human and veterinary medicine regarding the indications for, efficacy of, and controversies surrounding glucocorticoid (GC) administration in the emergency and critical care (ECC) setting, and to provide an overview of the most commonly used synthetic GC formulations.

MEDICATIONS

Synthetic GCs vary in GC and mineralocorticoid potency, hypothalamic pituitary axis suppression, duration of action, route of administration, and clinical indication for use. Some of the GC compounds commonly used in human and veterinary ECC include hydrocortisone, prednisone, methylprednisolone, and dexamethasone.

INDICATIONS FOR USE

GCs are used in human and veterinary ECC for a variety of disorders including anaphylaxis, acute lung injury/acute respiratory distress syndrome, septic shock, and spinal cord injury. Evidence for morbidity or mortality benefit with administration of GC within these populations exists; however, data are sparse and often conflicting.

ADVERSE EFFECTS AND CONTRAINDICATIONS

Routine use of GC in some conditions such as trauma, hemorrhagic shock, and traumatic brain injury is likely contraindicated. GC use has been associated with hyperglycemia, pneumonia, urinary tract infection, gastrointestinal ulceration, or increased mortality in some populations.

Hypoxia mediated pulmonary edema: potential influence of oxidative stress, sympathetic activation and cerebral blood flow

BACKGROUND

Neurogenic pulmonary edema (NPE) is a non-cardiogenic form of pulmonary edema that can occur consequent to central neurologic insults including stroke, traumatic brain injury, and seizure. NPE is a public health concern due to high morbidity and mortality, yet the mechanism(s) are unknown. We hypothesized that NPE, evoked by cerebral hypoxia in the presence of systemic normoxia, would be accompanied by sympathetic activation, oxidative stress, and compensatory antioxidant mechanisms.

METHODS

Thirteen Walker hounds were assigned to cerebral hypoxia (SaO2 ~ 55 %) with systemic normoxia (SaO2 ~ 90 %) (CH; n = 6), cerebral and systemic (global) hypoxia (SaO2 ~ 60 %) (GH; n = 4), or cerebral and systemic normoxia (SaO2 ~ 90 %) (CON; n = 3). Femoral venous (CH and CON) perfusate was delivered via cardiopulmonary bypass to the brain and GH was induced by FiO2 = 10 % to maintain the SaO2 at ~60 %. Lung wet to lung dry weight ratios (LWW/LDW) were assessed as an index of pulmonary edema in addition to hemodynamic measurements. Plasma catecholamines were measured as markers of sympathetic nervous system (SNS) activity. Total glutathione, protein carbonyls, and malondialdehyde were assessed as indicators of oxidative stress. Brain and lung compensatory antioxidants were measured with immunoblotting.

RESULTS

Compared to CON, LWW/LDW and pulmonary artery pressure were greater in CH and GH. Expression of hemeoxygenase-1 in brain was higher in CH compared to GH and CON, despite no group differences in oxidative damage in any tissue. Catecholamines tended to be higher in CH and GH.

CONCLUSION

Cerebral hypoxia, with systemic normoxia, is not systematically associated with an increase in oxidative stress and compensatory antioxidant enzymes in lung, suggesting oxidative stress did not contribute to NPE in lung. However, increased SNS activity may play a role in the induction of NPE during hypoxia.

Relative adrenal insufficiency in severe acute variceal and non-variceal bleeding: influence on outcomes

BACKGROUND & AIMS

Relative adrenal insufficiency (RAI) is common in critical illness and in cirrhosis, and is related with worse outcomes. The prevalence of RAI may be different in variceal and non-variceal bleeding and whether it may influence outcomes in these settings is unclear. This study assesses RAI and its prognostic implications in cirrhosis with variceal bleeding and in peptic ulcer bleeding.

METHODS

Patients with severe bleeding (systolic pressure <100 mmHg and/or haemoglobin <8 g/L) from oesophageal varices or from a peptic ulcer were included. Adrenal function was evaluated within the first 24 h and RAI was diagnosed as delta cortisol <250 nmol/L after 250 μg of i.v. corticotropin.

RESULTS

Sixty-two patients were included, 36 had cirrhosis and variceal bleeding and 26 without cirrhosis had ulcer bleeding. Overall, 15 patients (24%) had RAI, 8 (22%) with variceal and 7 (24%) with ulcer bleeding. Patients with RAI had higher rate of bacterial infections. Baseline serum and salivary cortisol were higher in patients with RAI (P < 0.001) while delta cortisol was lower (P < 0.001). There was a good correlation between plasma and salivary cortisol (P < 0.001). The probability of 45-days survival without further bleeding was lower in cirrhotic patients with variceal bleeding and RAI than in those without RAI (25% vs 68%, P = 0.02), but not in non-cirrhotic patients with peptic ulcer bleeding with or without RAI (P = 0.75).

CONCLUSION

The prevalence of RAI is similar in ulcer bleeding and in cirrhosis with variceal bleeding. Cirrhotic patients with RAI, but not those with bleeding ulcers, have worse prognosis.

Normothermic perfusion machine in liver transplant with cardiac death donor grafts

The increasing difference between the number of patients in waiting lists for liver transplantation and the number of available donors has generated a great interest in the use of non-ideal organs, like grafts obtained from cardiac death donors (DCD). However, the extreme sensibility to ischemia of these livers results in a low utilization rate and a high percentage of post-transplant complications and re-transplantation. Normothermic perfusion machines (NMP) emerged as an alternative that tries to maintain the viability of the organ and even to improve its function. This review focuses on current results of DCD liver transplantation and on the role that NMP may have in this field.

Low-dose hydrocortisone reduces norepinephrine duration in severe burn patients: a randomized clinical trial

Introduction

The aim of this study was to assess the effect of low-dose corticosteroid therapy in reducing shock duration after severe burn.

Methods

A placebo-controlled, double-blind, randomized clinical trial (RCT) was performed on two parallel groups in the burn intensive care unit (ICU). Patients were randomized to receive either low-dose corticosteroid therapy or placebo for seven days. A corticotropin test was performed at the time of randomization, before the administration of the treatment dose. Thirty-two severely burned patients with refractory shock (>0.5 μg/kg/min of norepinephrine) were prospectively included in the study.

Results

We included 12 patients in the hydrocortisone-treated group and 15 patients in the placebo group in the final analysis. Among these patients, 21 were nonresponders to the corticotropin test. Median norepinephrine treatment duration (primary objective) was significantly lower in the corticosteroid-treated versus the placebo group (57 hours versus 120 hours, P = 0.035). The number of patients without norepinephrine 72 hours after inclusion was significantly lower in the treated group (P = 0.003, log-rank test analysis). The total quantities of norepinephrine administered to patients were lower in the hydrocortisone-treated versus the placebo group (1,205 μg/kg (1,079 to 2,167) versus 1,971 μg/kg (1,535 to 3,893), P = 0.067). There was no difference in terms of ICU or hospital length of stay, sepsis incidence, cicatrization or mortality.

Conclusions

In this placebo-controlled, randomized, double-blind clinical trial, we show for the first time that the administration of low-dose hydrocortisone in burn patients with severe shock reduces vasopressor administration.

Trial registration

Clinicaltrial.gov NCT00149123. Registered 6 September 2005.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0740-0) contains supplementary material, which is available to authorized users.

Critical illness-related corticosteroid insufficiency in cirrhotic patients with acute gastroesophageal variceal bleeding: risk factors and association with outcome*

OBJECTIVES

Critical illness-related corticosteroid insufficiency can adversely influence the prognosis of critically ill patients. However, its impact on the outcomes of patients with cirrhosis and acute gastroesophageal variceal bleeding remains unknown. We evaluated adrenal function using short corticotropin stimulation test in patients with cirrhosis and gastroesophageal variceal bleeding. The main outcomes analyzed were 5-day treatment failure and 6-week mortality.

DESIGN

Prospective observational study.

SETTING

Ten-bed gastroenterology-specific medical ICU at a 3,613-bed university teaching hospital in Taiwan.

PATIENTS

Patients with liver cirrhosis and acute gastroesophageal variceal bleeding.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We evaluated adrenal function using short corticotropin stimulation test in 157 episodes of gastroesophageal variceal bleeding in 143 patients with cirrhosis. Critical illness-related corticosteroid insufficiency occurred in 29.9% of patients. The patients with critical illness-related corticosteroid insufficiency had higher rates of treatment failure and 6-week mortality (63.8% vs 10.9%, 42.6% vs 6.4%, respectively; p < 0.001). The cumulative rates of survival at 6 weeks were 57.4% and 93.6% for the critical illness-related corticosteroid insufficiency group and normal adrenal function group, respectively (p < 0.001). The cortisol response to corticotropin was inversely correlated with Model for End-Stage Liver Disease and Child-Pugh scores and positively correlated with the levels of high-density lipoprotein and total cholesterol. Hypovolemic shock, high-density lipoprotein, platelet count, and bacterial infection at inclusion are independent factors predicting critical illness-related corticosteroid insufficiency, whereas critical illness-related corticosteroid insufficiency, Model for End-Stage Liver Disease score, hypovolemic shock, hepatocellular carcinoma, and active bleeding at endoscopy are independent factors to predict treatment failure. Multivariate analysis also identified Model for End-Stage Liver Disease score, hypovolemic shock, and bacterial infection at inclusion as independent factors associated with 6-week mortality.

CONCLUSIONS

Critical illness-related corticosteroid insufficiency is common in cirrhotic patients with acute gastroesophageal variceal bleeding and is an independent factor to predict 5-day treatment failure.

[Interaction between hypnotic agents and the hypothalamic-pituitary-adrenocorticotropic axis during surgery]

During stress, the relationship between the central nervous system and the immune system is essential to maintain homeostasis. The main neuroendocrine system involved in this interaction is the hypothalamic-pituitary-adrenal axis (HPA), which via the synthesis of glucocorticoids will modulate the intensity of the inflammatory response. Anaesthetic agents could be interacting with the HPA axis during surgery. Although etomidate currently remains in the center of the discussions, it seems, at least experimentally, that most hypnotics have the capacity to modulate the synthesis of adrenal steroids. Nevertheless, with the large literature on this subject, etomidate seems to be the most deleterious hypnotic agent on the HPA axis function. Its use should be limited when HPA axis is already altered.

Characterizing vasopressin and other vasoactive mediators released during resuscitation of trauma patients

BACKGROUND

We sought to perform the first characterization of vasopressin and other vasoactive mediators released during resuscitation of hypotensive trauma patients.

METHODS

This institutional review board-approved study was conducted under waiver of consent. Adults with clinical evidence of acute traumatic injury and systolic blood pressure less than or equal to 90 mm Hg within 1 hour of arrival were evaluated at our Level I trauma center. Two hundred three patients were screened with 50 enrolled from February 2010 to February 2011. Demographic information was also collected. Blood samples were obtained at 0, 30, 60, 90, 120, and 240 minutes after arrival, and assays were performed for vasopressin, angiotensin II, epinephrine, and cortisol. We assessed the significance of variation in these vasoactive mediators with injury and transfusion of more than 600 mL, with adjustment for time using repeated-measures linear models in log units.

RESULTS

We found that vasopressin (p = 0.005) and epinephrine (p = 0.01) increased significantly with injury, while angiotensin (p = 0.60) and cortisol (p = 0.46) did not and that vasopressin (p < 0.001) and epinephrine (p = 0.004) increased significantly in patients requiring transfusion of more than 600 mL but angiotensin II (p = 0.11) and cortisol (p = 0.90) did not. Relatively low levels of vasopressin (<30 pg/mL) were observed at least once during the first 2 hours in 88% of trauma patients, and abnormally low epinephrine levels (<100 pg/mL) were observed at least once during the first 2 hours in 18% of trauma patients.

CONCLUSION

This is the first clinical trial to serially evaluate vasopressin and other vasoactive mediators following trauma during the resuscitation phase. Vasopressin, in particular, and epinephrine seem to be the key mediators produced in the human response to severe injury. A deficiency of vasopressin may contribute to intractable shock after trauma.

LEVEL OF EVIDENCE

Prognostic/epidemiologic study, level III.

Therapeutic strategies for high-dose vasopressor-dependent shock

There is no consensual definition of refractory shock. The use of more than 0.5 mcg/kg/min of norepinephrine or epinephrine to maintain target blood pressure is often used in clinical trials as a threshold. Nearly 6% of critically ill patients will develop refractory shock, which accounts for 18% of deaths in intensive care unit. Mortality rates are usually greater than 50%. The assessment of fluid responsiveness and cardiac function can help to guide therapy, and inotropes may be used if hypoperfusion signs persist after initial resuscitation. Arginine vasopressin is frequently used in refractory shock, although definite evidence to support this practice is still missing. Its associations with corticosteroids improved outcome in observational studies and are therefore promising alternatives. Other rescue therapies such as terlipressin, methylene blue, and high-volume isovolemic hemofiltration await more evidence before use in routine practice.

Severe hemodynamic instability in a patient with suspected hepatoadrenal syndrome during liver transplantation -A case report-

Adrenal insufficiency, which is related to hemodynamic instability and increased mortality, has been reported in patients with advanced liver disease regardless of the presence of septic conditions. In this regard, the hepatoadrenal syndrome has been recently proposed as adrenal insufficiency in critically ill patients with liver disease. We describe here a 67-year-old female patient with hepatic failure and adrenal insufficiency. The patient showed stable vital signs and no evidence of sepsis preoperatively. Despite hydrocortisone replacement and inotropics administration, severe intraoperative hemodynamic instability was observed. Hydrocortisone administration was continued postoperatively, nevertheless inotropics could not be tapered. On postoperative day 11, the patient died due to pneumonia and septic shock. Hepatoadrenal syndrome may have played a key role in her severe hemodynamic fluctuation and poor outcome, reinforcing the importance of adrenal function in the liver transplantation surgery.

The promise of CaMKII inhibition for heart disease: preventing heart failure and arrhythmias

INTRODUCTION

Calcium-calmodulin-dependent protein kinase II (CaMKII) has emerged as a central mediator of cardiac stress responses which may serve several critical roles in the regulation of cardiac rhythm, cardiac contractility and growth. Sustained and excessive activation of CaMKII during cardiac disease has, however, been linked to arrhythmias, and maladaptive cardiac remodeling, eventually leading to heart failure (HF) and sudden cardiac death.

AREAS COVERED

In the current review, the authors describe the unique structural and biochemical properties of CaMKII and focus on its physiological effects in cardiomyocytes. Furthermore, they provide evidence for a role of CaMKII in cardiac pathologies, including arrhythmogenesis, myocardial ischemia and HF development. The authors conclude by discussing the potential for CaMKII as a target for inhibition in heart disease.

EXPERT OPINION

CaMKII provides a promising nodal point for intervention that may allow simultaneous prevention of HF progression and development of arrhythmias. For future studies and drug development there is a strong rationale for the development of more specific CaMKII inhibitors. In addition, an improved understanding of the differential roles of CaMKII subtypes is required.

Etomidate increases susceptibility to pneumonia in trauma patients

PURPOSE

To investigate the impact of etomidate on the rate of hospital-acquired pneumonia (HAP) in trauma patients and the effects of hydrocortisone in etomidate-treated patients.

METHODS

This was a sub-study of the HYPOLYTE multi-centre, randomized, double-blind, placebo-controlled trial of hydrocortisone in trauma patients (NCT00563303). Inclusion criterion was trauma patient with mechanical ventilation (MV) of ≥48 h. The use of etomidate was prospectively collected. Endpoints were the results of the cosyntropin test and rate of HAP on day 28 of follow-up.

RESULTS

Of the 149 patients enrolled in the study, 95 (64 %) received etomidate within 36 h prior to inclusion. 79 (83 %) of 95 patients receiving etomidate and 34 of the 54 (63 %) not receiving etomidate had corticosteroid insufficiency (p = 0.006). The administration of etomidate did not alter basal cortisolemia (p = 0.73), but it did decrease the delta of cortisolemia at 60 min (p = 0.007). There was a correlation between time from etomidate injection to inclusion in the study and sensitivity to corticotropin (R (2) = 0.19; p = 0.001). Forty-nine (51.6 %) patients with etomidate and 16 (29.6 %) patients without etomidate developed HAP by day 28 (p = 0.009). Etomidate was associated with HAP on day 28 in the multivariate analysis (hazard ratio 2.48; 95 % confidence interval 1.19-5.18; p = 0.016). Duration of MV with or without etomidate was not significantly different (p = 0.278). Among etomidate-exposed patients, 18 (40 %) treated with hydrocortisone developed HAP compared with 31 (62 %) treated with placebo (p = 0.032). Etomidate-exposed patients treated with hydrocortisone had fewer ventilator days (p < 0.001).

CONCLUSIONS

Among the patients enrolled in the study, etomidate did not alter basal cortisolemia, but it did decrease reactivity to corticotropin. We suggest that in trauma patients, etomidate is an independent risk factor for HAP and that the administration of hydrocortisone should be considered after etomidate use.

Review article: update in trauma anesthesiology: perioperative resuscitation management

The management of trauma patients has matured significantly since a systematic approach to trauma care was introduced nearly a half century ago. The resuscitation continuum emphasizes the effect that initial therapy has on the outcome of the trauma patient. The initiation of this continuum begins with prompt field medical care and efficient transportation to designated trauma centers, where lifesaving procedures are immediately undertaken. Resuscitation with packed red blood cells and plasma, in parallel with surgical or interventional radiologic source control of bleeding, are the cornerstones of trauma management. Adjunctive pharmacologic therapy can assist with resuscitation. Tranexamic acid is used in Europe with good results, but the drug is slowly being added to the pharmacy formulary of trauma centers in United States. Recombinant factor VIIa can correct abnormal coagulation values, but its outcome benefit is less clear. Vasopressin shows promise in animal studies and case reports, but has not been subjected to a large clinical trial. The concept of "early goal-directed therapy" used in sepsis may be applicable in trauma as well. An early, appropriately aggressive resuscitation with blood products, as well as adjunctive pharmacologic therapy, may attenuate the systemic inflammatory response of trauma. Future investigations will need to determine whether this approach offers a similar survival benefit.

Hydrocortisone administration increases pulmonary artery pressure in asphyxiated newborn piglets reoxygenated with 100% oxygen

In severely asphyxiated neonates developing vasopressor-resistant shock, hydrocortisone is commonly used to improve perfusion. However, its acute haemodynamic effects in asphyxiated neonates are largely unknown. In a swine model of neonatal asphyxia, effects of hydrocortisone on systemic and pulmonary circulations were examined. Piglets (1-3d, 1.5-2.4kg) were acutely instrumented to measure heart rate, systemic and pulmonary artery pressures, and pulmonary artery flow. After 2h of normocapnic hypoxia, animals were resuscitated with 100% oxygen for 1h followed by 21% oxygen for 3h. Intravenous hydrocortisone (1mg/kg) or saline was given in a blinded, randomized fashion 2h after reoxygenation (n=6/group). Haemodynamic parameters, blood gases, plasma cortisol, as well as levels of endothelin-1, nitrite/nitrate, nitrotyrosine, matrix metalloproteinases-2 and -9 in the lung were analysed. Severe hypoxia caused metabolic acidosis (mean pH: 6.91-6.97, mean plasma lactate: 17.2-18.3mM), tachycardia and shock. Hydrocortisone did not affect systemic haemodynamics which recovered with reoxygenation, but it increased pulmonary artery pressure at 90-120min after administration (36±3 vs. 27±2 and 26±1mmHg for hypoxia-reoxygenation control and sham-operated piglets, respectively, P<0.05). In the lung tissue, hydrocortisone significantly increased endothelin-1 and nitrite/nitrate levels, but had no effect on nitrotyrosine. Further, it decreased lung matrix metalloproteinase-9, but not matrix metalloproteinase-2, activity, which were both elevated with hypoxia-reoxygenation. It is most likely that the increase in pulmonary artery pressure observed after hydrocortisone treatment was associated with increased endothelin-1 level in the lung. Our findings caution the use of hydrocortisone as a first-intention treatment of shock in asphyxiated neonates.

Glucocorticoid-related signaling effects in vascular smooth muscle cells

Mineralocorticoid receptor blockade protects from angiotensin II-induced target-organ damage. 11beta-Hydroxysteroid dehydrogenase type 2 protects the mineralocorticoid receptor from activation by glucocorticoids; however, high glucocorticoid concentrations and absent 11beta-hydroxysteroid dehydrogenase type 2 in some tissues make glucocorticoids highly relevant mineralocorticoid receptor ligands. We investigated the effects of corticosterone (10(-6) to 10(-12) mol/L) on early vascular mineralocorticoid receptor signaling by Western blotting, confocal microscopy, and myography. Corticosterone initiated extracellular signal-regulated kinase 1/2 phosphorylation in rat vascular smooth muscle cells at > or =10(-11) mol/L doses. Protein synthesis inhibitors had no effect, indicating a nongenomic action. Corticosterone also stimulated c-Jun N-terminal kinase, p38, Src, and Akt phosphorylation at 15 minutes and enhanced angiotensin II-induced signaling at 5 minutes. A specific epidermal growth factor receptor blocker, AG1478, as well as the Src inhibitor PP2, markedly reduced corticosterone-induced extracellular signal-regulated kinase 1/2 phosphorylation, as did preincubation of cells with the mineralocorticoid receptor antagonist spironolactone. Silencing mineralocorticoid receptor with small interfering RNA abolished corticosterone-induced effects. Corticosterone (10(-9) mol/L) enhanced phenylephrine-induced contraction of intact aortic rings. These effects were dependent on the intact endothelium, mineralocorticoid receptor, and mitogen-activated protein kinase kinase 1/extracellular signal-regulated kinase signaling. We conclude that corticosterone induces rapid mineralocorticoid receptor signaling in vascular smooth muscle cells that involves mitogen-activated protein kinase kinase/extracellular signal-regulated kinase-dependent pathways. These new mineralocorticoid receptor-dependent signaling pathways suggest that glucocorticoids may contribute to vascular disease via mineralocorticoid receptor signaling, independent of circulating aldosterone.

Adrenal insufficiency in pediatric critical illness: controversies regarding its prevalence, pathogenesis, definition and management

Proper functioning of the hypothalamic–pituitary–adrenal axis is necessary for normal homeostasis in children and especially under conditions of stress, such as critical illness. Disturbances of this axis have been classified collectively under the heading of adrenal insufficiency. Although the majority of literature has focused on children with septic shock, more recent evidence suggests that adrenal insufficiency occurs in a much broader group of critically ill children. Its etiology in pediatric critical illness remains unclear but is most likely multifactorial. Several studies have suggested possible diagnostic criteria for adrenal insufficiency in pediatric critical illness; however, to date none of these biochemical definitions have been validated. Similarly, current management of this condition in children remains based primarily on an empiric, best-practice approach. Future large-scale studies are needed to elucidate the prevalence, pathogenesis, definition, diagnosis and management of this condition.

A history of adjunctive glucocorticoid treatment for pediatric sepsis: moving beyond steroid pulp fiction toward evidence-based medicine

OBJECTIVES

To review the history of clinical use of corticosteroids with particular reference to adjunctive therapy for severe pediatric sepsis and, in this context, to provide an overview of what is known, what is not known, and what research questions are particularly relevant at this time.

DATA SOURCE

Literature review using PubMed, cross-referenced article citations, and the Internet.

CONCLUSIONS

The history of corticosteroid use in clinical medicine has been colorful, noisy, and always controversial. Therapeutic corticosteroid indications that initially seemed rational have frequently been refuted on closer, rigorous clinical trial inspection. Although it may be prudent to provide stress-dose steroids to children with septic shock who are clinically at risk for adrenal insufficiency (chronic or recent steroid use, purpura fulminans, etomidate or ketoconazole administration, hypothalamic, pituitary, adrenal disease), the safety and efficacy of stress-dose steroids as general adjunctive therapy for pediatric septic shock have not been established. Glucocorticoid administration does add potential risk to critically ill children. In particular, although adjunctive corticosteroids may hasten resolution of unstable hemodynamics in septic shock, this may occur at the metabolic cost of hyperglycemia. Clinical practice that fosters innovative therapy (off-label use) over research probably represents bad medical and social policy. Accordingly, pediatric critical care researchers have a responsibility to generate pediatric-specific evidence-based medicine for adjunctive corticosteroid therapy for severe sepsis in children.

Indications and practical use of replacement dose of corticosteroids in critical illness

PURPOSE OF REVIEW

Ongoing and severe systemic inflammation affecting critically ill patients may cause adrenal insufficiency and steroid resistance in target cells. As the appropriate diagnosis of this clinical entity remains a challenge, indication and practical use of corticosteroid replacement therapy in the critically ill is generally directed by clinical symptoms and features.

RECENT FINDINGS

In the last 2 years, a series of clinical trials have been undertaken to investigate corticosteroid replacement therapy in critically ill patients with severe systemic inflammation of various origin. Improvements of morbidity have been demonstrated in some studies. The data of recent studies should lead to a restriction of corticosteroid replacement therapy in critically ill patients. The purpose of this review is to investigate indications and the best current practical use of corticosteroid replacement therapy in critically ill patients in the absence of accurate laboratory assessment of adrenal insufficiency.

SUMMARY

Corticosteroid replacement therapy may improve morbidity and mortality in specific target groups of critically ill patients. The appropriate target groups remain to be refined. To demonstrate this, additional studies are required on endocrine disorder in critical illness and corticosteroid replacement therapy.

Adrenal insufficiency in liver disease - what is the evidence?

Recently, treatment with corticosteroids in the setting of septic shock and adrenal insufficiency has been shown to decrease mortality. In septic patients, a blunted response to adrenal stimulation identifies patients with a poorer prognosis who may benefit from corticosteroid supplementation. This condition has been termed relative adrenal insufficiency (RAI). Given the similarities between septic shock and liver failure, a number of groups have now studied the incidence of RAI in various forms of liver disease. Although different definitions of RAI exist, the current literature suggests that RAI is common, being seen in 33% of acute liver failure patients and up to 65% of patients with chronic liver disease and sepsis. The finding that RAI can exist in the absence of sepsis and may be as high as 92% of patients undergoing liver transplantation using a steroid free protocol has led one group to propose the term hepatoadrenal syndrome. The purpose of this review is to summarise the existing evidence for adrenal insufficiency in liver disease, to examine the possibility that adrenal dysfunction in liver disease may have a separate pathogenesis to that observed in sepsis and to provide insight into the potential areas for further research into this condition.

Relative adrenal insufficiency: an identifiable entity in nonseptic critically ill patients?

OBJECTIVE

To determine whether relative adrenal insufficiency (RAI) can be identified in nonseptic hypotensive patients in the intensive care unit (ICU).

DESIGN

Retrospective study in a medical-surgical ICU of a university hospital.

PATIENTS

One hundred and seventy-two nonseptic ICU patients (51% after trauma or surgery), who underwent a short 250 microg ACTH test because of > 6 h hypotension or vasopressor/inotropic therapy.

MEASUREMENTS

On the test day, the Simplified Acute Physiology Score II (SAPS II) and Sequential Organ Failure Assessment (SOFA) score were calculated to estimate disease severity. The ICU mortality until day 28 was recorded. Best discriminative levels of baseline cortisol, increases and peaks were established using receiver operating characteristic curves. These and corticosteroid treatment (in n = 112, 65%), among other variables, were examined by multiple logistic regression and Cox proportional hazard regression analyses to find independent predictors of ICU mortality until day 28.

RESULTS

ICU mortality until day 28 was 23%. Nonsurvivors had higher SAPS II and SOFA scores. Baseline cortisol levels correlated directly with albumin levels and SAPS II. In the multivariate analyses, a cortisol baseline > 475 nmol/l and cortisol increase < 200 nmol/l predicted mortality, largely dependent on disease severity but independent of albumin levels. Corticosteroid (hydrocortisone) treatment was not associated with an improved outcome, regardless of the ACTH test results.

CONCLUSION

In nonseptic hypotensive ICU patients, a low cortisol/ACTH response and treatment with corticosteroids do not contribute to mortality prediction by severity of disease. The data thus argue against RAI identifiable by cortisol/ACTH testing and necessitating corticosteroid substitution treatment in these patients.

Hypothalamic pituitary adrenal function during critical illness: limitations of current assessment methods

CONTEXT

Activation of the hypothalamic-pituitary-adrenal (HPA) axis represents one of several important responses to stressful events and critical illnesses. Despite a large volume of published data, several controversies continue to be debated, such as the definition of normal adrenal response, the concept of relative adrenal insufficiency, and the use of glucocorticoids in the setting of critical illness.

OBJECTIVES

The primary objective was to review some of the modulating factors and limitations of currently used methods of assessing HPA function during critical illness and provide alternative approaches in that setting.

DESIGN

This was a critical review of relevant data from the literature with inclusion of previously published as well as unpublished observations by the author. Data on HPA function during three different forms of critical illnesses were reviewed: experimental endotoxemia in healthy volunteers, the response to major surgical procedures in patients with normal HPA, and the spontaneous acute to subacute critical illnesses observed in patients treated in intensive care units.

SETTING

The study was conducted at an academic medical center.

PATIENTS/PARTICIPANTS

Participants were critically ill subjects.

INTERVENTION

There was no intervention.

MAIN OUTCOME MEASURE

The main measure was to provide data on the superiority of measuring serum free cortisol during critical illness as contrasted to those of total cortisol measurements.

RESULTS

Serum free cortisol measurement is the most reliable method to assess adrenal function in critically ill, hypoproteinemic patients. A random serum free cortisol is expected to be 1.8 microg/dl or more in most critically ill patients, irrespective of their serum binding proteins. Because the free cortisol assay is not currently available for routine clinical use, alternative approaches to estimate serum free cortisol can be used. These include calculated free cortisol (Coolens' method) and determining the free cortisol index (ratio of serum cortisol to transcortin concentrations). Preliminary data suggest that salivary cortisol measurements might be another alternative approach to estimating the free cortisol in the circulation. When serum binding proteins (albumin, transcortin) are near normal, measurements of total serum cortisol continue to provide reliable assessment of adrenal function in critically ill patients, in whom a random serum total cortisol would be expected to be 15 microg/dl or more in most patients. In hypoproteinemic critically ill subjects, a random serum total cortisol level is expected to be 9.5 microg/dl or more in most patients. Data on Cosyntropin-stimulated serum total and free cortisol levels should be interpreted with the understanding that the responses in critically ill subjects are higher than those of healthy ambulatory volunteers. The Cosyntropin-induced increment in serum total cortisol should not be used as a criterion for defining adrenal function, especially in critically ill patients.

CONCLUSIONS

The routine use of glucocorticoids during critical illness is not justified except in patients in whom adrenal insufficiency was properly diagnosed or others who are hypotensive, septic, and unresponsive to standard therapy. When glucocorticoids are used, hydrocortisone should be the drug of choice and should be given at the lowest dose and for the shortest duration possible. The hydrocortisone dose (50 mg every 6 h) that is mistakenly labeled as low-dose hydrocortisone leads to excessive elevation in serum cortisol to values severalfold greater than those achieved in patients with documented normal adrenal function. The latter data should call into question the current practice of using such doses of hydrocortisone even in the adrenally insufficient subjects.

Year in review 2005: Critical Care - resource management

During 2005 Critical Care published several original papers dealing with resource management. Emphasis was placed on sepsis, especially the coagulation cascade, prognosis and resuscitation. The papers highlighted important aspects of the pathophysiology of coagulation and inflammation in sepsis, as well as dealing with the proper use of newly developed compounds. Several aspects of prognosis in critically ill patients were investigated, focusing on biological markers and clinical indexes. Resuscitation received great attention, dealing with the effects of fluid infusion in hemodynamics and the lung. The information obtained can be used to address unknown effects of established therapies, to enlighten current clinical discussion on controversial topics, and to introduce novel medical resources and strategies. Future clinical work will rely heavily on these preclinical and laboratory data.