Adrenocortical function: an indicator of severity of disease and survival in chronic critically ill patients

Leptin ameliorates burn-induced multiple organ damage and modulates postburn immune response in rats

The present study was designed to determine whether exogenous leptin reduces remote organ injury in the rats with thermal burn trauma. Leptin (10 microg/kg) or saline was administered intraperitoneally after burn injury, and the rats were decapitated at either 6 or 24 h. Plasma samples of 24-h burn group were assayed for the determination of monocyte and neutrophil apoptosis. Thermal injury increased tissue-associated myeloperoxidase (MPO) activity and microscopic damage scores in the lung, liver, stomach, colon and kidney of both 6- and 24-h burn groups. In the 6-h burn group, leptin reduced microscopic damage score in the liver and kidney only, while damage scores in the 24-h burn group were reduced in all the tissues except the lung. Also, in both burn groups, leptin reduced elevated MPO activity in all tissues except the lung. The percentage of mononuclear cells was significantly reduced at the 24 h of burn injury, while the granulocyte percentage was increased. Leptin treatment, however, had no significant effect on burn-induced reversal of white blood cell ratios. On the other hand, burn-induced increase in the death of mononuclear cells and granulocytes was significantly reduced in leptin-treated rats. The results of the present study suggest that leptin may provide a therapeutic benefit in diminishing burn-induced inflammation and associated multiple organ failure.

The relative adrenal insufficiency syndrome revisited: which patients will benefit from low-dose steroids?

PURPOSE OF REVIEW

Several clinical studies have given rise to optimism about low-dose steroid treatment in patients with sepsis. It reduces time to shock reversal and may even have a positive effect on mortality. The pathophysiology of the relative adrenal insufficiency syndrome has not yet been determined, and the usefulness of basal and stimulated cortisol levels in diagnosing this syndrome is still uncertain. This review will examine recent evidence to elucidate these questions.

RECENT FINDINGS

Studies performed in more than 1000 patients in intensive care show convincingly that in general serum cortisol levels are increased. Basal or stimulated cortisol levels are at best useful to predict mortality in patients in intensive care, not to decide which patients to treat or when to discontinue treatment. Measuring free cortisol concentrations rather than total cortisol concentrations in critically ill patients may lead to new research strategies to identify the mode of action of low-dose steroid treatment.

SUMMARY

It has been shown that low-dose corticosteroid administration to catecholamine-dependent patients in septic shock results in shock reversal. There seems to be a relative shortage of cortisol, because low-dose hydrocortisone administration resulting in cortisol levels as much as four times the already increased levels results in shock reversal. Strong evidence for a positive effect on mortality is still lacking, perhaps because of the relatively low number of patients investigated. A very important topic in interpreting studies is that total (free plus protein-bound) cortisol has been measured. Future studies should also measure free cortisol concentrations, which could add to our knowledge of the pathophysiology and treatment of the relative adrenal insufficiency syndrome. On the basis of current knowledge, there is no evidence to support a treatment strategy based on a random or stimulated cortisol level. At the moment, rapid hemodynamic improvement of catecholamine-dependent patients after the administration of low-dose corticosteroids still seems the best available clue to diagnosis.

Serum cortisol as a predictive marker of the outcome in patients resuscitated after cardiopulmonary arrest

OBJECTS

To analyze the relationship between stress hormones (arginine vasopressin (ADH), adrenocorticotropic hormone (ACTH) and cortisol and the outcome of patients resuscitated after cardiopulmonary arrest (CPA).

METHODS

Thirty-six patients were enrolled in this study. In 36 of the resuscitated cases, 27 were non-survivors and 9 survived. The survival group was defined as cases either in a persistent vegetative state, with some disability or good recovery 1 month after return of spontaneous circulation (ROSC). The non-survival group was defined as cases who died within 1 month.

RESULTS

The plasma ADH and ACTH levels and the serum cortisol levels in both the surviving and the non-surviving patients were 82.3+/-74.5 and 149.6+/-135.4 (pg/ml), 239.7+/-327.4 and 282.4+/-553.0 (pg/ml), 34.1+/-11.2 and 19.0+/-12.8 (g/ml) (mean+/-S.D., respectively). The plasma ADH and ACTH levels showed no significant difference between the two groups. The serum cortisol levels were significantly higher in survivors than in the non-survivors (P=0.029). We also used the receiving-operating characteristics (ROC) curves to evaluate the optimal cutoff value of the concentration of serum cortisol as a predictive maker of non-surviving patients. The cutoff value of 16.7 g/ml for the concentrations of serum cortisol was a 1.00 positive predictive value and a 1.00 specificity at a 0.519 negative predictive and a 0.409 sensitivity for predicting non-surviving patients. The area under the ROC curve was calculated to be 0.858 at a prevalence of 0.58. The plasma ADH levels correlated significantly and positively with the plasma ACTH levels (r=0.516, P<0.0010).

CONCLUSIONS

We concluded that the serum cortisol levels were significantly higher in survivors than in non-survivors resuscitated after CPA.

Role of Corticosteroids in Septic Shock

OBJECTIVE

To highlight the role of relative adrenal insufficiency in the outcome of critically ill patients with sepsis and systematically review the literature regarding the use of corticosteroids for management of severe sepsis/septic shock.

DATA SOURCES

A computerized search of MEDLINE, EMBASE, and the Cochrane Database was undertaken from 1966 to March 2003 using the search terms intensive care unit, critical care, corticosteroids, glucocorticoids, adrenal insufficiency, sepsis, and septic shock. Bibliographies of all articles retrieved were searched for relevant articles not identified by the computerized search.

DATA EXTRACTION/SYNTHESIS

Six trials were identified after publication of the meta-analyses (1995), with a total of 505 patients. The results of these trials in septic shock suggest that low-dose corticosteroids can reduce vasopressor requirements and hasten reversal of shock. Some of these trials suggested a possible mortality benefit from therapy, and no trial demonstrated an increase in mortality or significant adverse effects. The benefit of this therapy may depend on the presence of relative adrenal insufficiency, as identified by the adrenocorticotropic hormone stimulation test.

CONCLUSIONS

Low-dose corticosteroids should be administered to patients with septic shock empirically, but should be discontinued if relative adrenal insufficiency is not confirmed.

Cortisol levels and mortality in severe sepsis

OBJECTIVE

Serum cortisol levels rise in response to the stress of critical illness but the optimal range of serum cortisol in such settings is not clearly defined. The objectives of this study were to determine the range of serum cortisol levels in a group of medical intensive care unit patients with severe sepsis/septic shock using uniform criteria, and to correlate serum cortisol levels to mortality.

DESIGN AND PATIENTS

In a prospective observational fashion, 100 medical intensive care unit patients at Northwestern Memorial Hospital in Chicago were enrolled within 48 h of developing severe sepsis/septic shock as defined by the American College of Chest Physicians/Society of Critical Care Medicine.

MEASUREMENTS

A serum cortisol level was measured during the morning hours in the first 48 h of developing severe sepsis/septic shock. The severity of critical illness was measured by the Acute Physiology and Chronic Health Evaluation II (APACHE II) score.

RESULTS

The average patient age was 63 +/- 17 years, 54 patients were men. The average APACHE II score for all patients was 23 +/- 7. In-hospital and 90-day mortality were 51% and 60%, respectively. Four patient groups were defined a priori based on morning serum cortisol levels and their in-hospital mortalities were as follows: group 1 (cortisol < or = 345 nmol/l), n = 11, mortality 54%; group 2 (cortisol 345-552 nmol/l), n = 19, mortality 53%; group 3 (cortisol 552-1242 nmol/l), n = 54, mortality 41%; and group 4 (cortisol > or = 1242 nmol/l), n = 16, mortality 81% (P < 0.01).

CONCLUSIONS

Cortisol levels were elevated in most patients with septic shock. Cortisol levels less than 552 nmol/l occurred in 30% of patients with septic shock but the mortality in these patients was not significantly increased. Serum cortisol levels > or = 1242 nmol/l were associated with significantly higher mortality.

Subjective versus objective stress in noncritically ill hospitalized and outpatient adult men

A cross-sectional study of 120 subjects was performed with the purpose of evaluating stress hormones and emotional stress (anxiety) in outpatient and hospitalized subjects. The aims were to determine the degree of objective stress, as well as to correlate this finding with subjective findings, estimated using Beck's Anxiety Inventory.. METHOD: Three populations were investigated, namely outpatient clinical cases (Group I, n = 30), hospitalized clinical individuals (Group II, n = 30), and hospitalized surgical candidates (Group III, n = 30). Controls (Group IV, n = 30) were healthy volunteers who were health-care professionals and students. To avoid hormone interactions, only men were enrolled in all groups. All hospitalized subjects were tested on admission and before therapeutic interventions. Fasting epinephrine, norepinephrine, and cortisol were measured in the morning, and Beck's Anxiety Inventory was adminstered by a trained psychologist. RESULTS: The 3 patient groups displayed higher anxiety levels than the controls. Hormone concentrations did not present remarkable changes and did not correlate with subjective stress (anxiety). CONCLUSIONS: 1) Subjective disorders (as determined with Beck's Anxiety Inventory ) were a common finding in both outpatient and hospitalized populations, without differences between the various groups; 2) Objective stress (as determined by elevated hormone levels) was more difficult to confirm-findings rarely exceeded the reference range; 3) Correlation between the two variables could not be demonstrated; 4) Further studies are necessary to define stress quantification and interpretation in patient populations, especially in relationship with nutritional diagnosis and dietetic prescription.

Clinical review: corticotherapy in sepsis

The use of glucocorticoids (corticotherapy) in severe sepsis is one of the main controversial issues in critical care medicine. These agents were commonly used to treat sepsis until the end of the 1980s, when several randomized trials casted serious doubt on any benefit from high-dose glucocorticoids. Later, important progress in our understanding of the role played by the hypothalamic–pituitary–adrenal axis in the response to sepsis, and of the mechanisms of action of glucocorticoids led us to reconsider their use in septic shock. The present review summarizes the basics of the physiological response of the hypothalamic–pituitary–adrenal axis to stress, including regulation of glucocorticoid synthesis, the cellular mechanisms of action of glucocorticoids, and how they influence metabolism, cardiovascular homeostasis and the immune system. The concepts of adrenal insufficiency and peripheral glucocorticoid resistance are developed, and the main experimental and clinical data that support the use of low-dose glucocorticoids in septic shock are discussed. Finally, we propose a decision tree for diagnosis of adrenal insufficiency and institution of cortisol replacement therapy.

The hypothalamic-pituitary-adrenal axis and low-dose glucocorticoids in the treatment of septic shock

Severe sepsis is the leading cause of death among patients in intensive care units. Recombinant activated protein C is the only substance known to directly improve morbidity and mortality. Adrenal insufficiency occurs frequently in patients with sepsis and is associated with poor outcome. Although high-dose glucocorticoids have not positively affected clinical outcome, small trials in which low-dose glucocorticoids were administered to patients with septic shock and relative adrenal insufficiency have shown decreased mortality. The main effect of glucocorticoids in low-doses apparently is exerted through correction of suppression of the hypothalamic-pituitary-adrenal axis. However, the therapeutic benefits of glucocorticoids may be related to their antiinflammatory properties and endogenous catecholamine-enhancing effects.

Baseline cortisol levels, cortisol response to corticotropin, and prognosis in late septic shock

The prognostic value of basal and corticotropin-stimulated cortisol concentration in patients with sepsis remains a controversial issue. In a retrospective cohort study, 82 consecutive patients with septic shock underwent a short corticotropin test performed more than 24 h after the onset of vasopressor therapy. Forty-one (50%) patients died within 28 days after the onset of septic shock. The mean (SD) basal cortisol level was 22.7 (10.6) microg/dL. With threshold values of 7 and 9 microg/dL maximal increases in cortisol level, 28 (34%) and 31 (38%) patients were, respectively, classified as nonresponders to the short corticotropin test. On multivariate analysis, a cortisol level >20 microg/dL (P = 0.0002), a maximal response to corticotropin <9 microg/dL (P = 0.044), abnormal lactate values (P = 0.0098), and positive blood cultures (P = 0.004) were independent predictors of 28-day mortality. In conclusion, high basal cortisol and low increase on corticotropin stimulation are predictors of a poor outcome in late septic shock. The underlying mechanisms of these prognostic patterns remain to be elucidated.

Stress-dose corticosteroid therapy for sepsis and acute lung injury or acute respiratory distress syndrome in critically ill adults

Sepsis and acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) are associated with high mortality rates despite recent therapeutic advances. Both disease states involve uncontrolled host defense responses that lead to inflammation, endothelial damage, enhanced coagulation, diminished fibrinolysis and fibroproliferation to produce microthrombi, and relative adrenal insufficiency. Corticosteroids inhibit the host defense response and may offer an inexpensive therapeutic option. Results of several randomized, double-blind studies demonstrated no survival benefit and higher secondary infection rates when supraphysiologic doses of corticosteroids were administered for less than 24 hours. Recently, the emphasis of research for corticosteroid therapy has involved adrenocortical replacement dosage regimens administered for several days to weeks, with doses corresponding to the stress level of the disease. Stress-dose therapy with hydrocortisone in patients with septic shock who require vasopressor support, especially if adrenal insufficiency is present, accelerates hemodynamic stability and reduces mortality. The frequency of gastrointestinal hemorrhage was higher with corticosteroid therapy than with placebo, but the occurrence of secondary infections was similar to that of placebo. The only randomized, double-blind study that evaluated stress-dose methylprednisolone therapy for ARDS was terminated early after only 24 patients were enrolled because therapy with methylprednisolone was associated with enhanced survival despite higher secondary infection rates. A multicenter study investigating stress-dose methylprednisolone for ARDS is under way and should provide valuable information. Sufficient data support stress-dose hydrocortisone therapy for vasopressor-dependent septic shock. Stress-dose methylprednisolone therapy for ALI-ARDS requires further study but may be warranted in cases of refractory infection-induced ARDS when impending mortality is likely.

Low serum cortisol in combination with high adrenocorticotrophic hormone concentrations are associated with poor outcome in children with severe meningococcal disease

OBJECTIVES

To study the correlation between serum concentrations of adrenocorticotrophic hormone (ACTH) and cortisol in relation to severity of disease in children with meningococcal sepsis.

METHODS

Subjects were children with meningococcal sepsis, admitted to the pediatric intensive care unit. Clinical data, laboratory values and blood samples were selected. Arterial cortisol, ACTH, interleukin 6 and tumor necrosis factor alpha concentrations were measured on admission and studied for their relation to severity of disease (sepsis, septic shock/survivors, septic shock/nonsurvivors).

RESULTS

Seventy-two patients fulfilled the criteria for meningococcal sepsis. Sixty-two of these children with positive blood cultures of Neisseria meningitidis, who were not treated with corticosteroids before admission, were included. Fifty of the 62 patients had septic shock. Twelve of those children (24%) died. The median age of the subjects was 2.6 years (range, 0.3 to 16.1 years). Cortisol values were significantly lower in non-survivors (median, 654 nmol/l) than in survivors (median, 2184 nmol/l) (P < 0.01). ACTH values were significantly higher in children who died (median, 1271 ng/l) than in survivors (85 ng/l) (P < 0.01). The median cortisol:ACTH ratio decreased significantly depending on the disease severity categories.

CONCLUSIONS

Low serum cortisol concentrations in combination with high ACTH concentrations are associated with poor outcome in children with severe meningococcal disease.

Adrenocortical function and multiple organ failure in severe sepsis

BACKGROUND

Some patients with severe sepsis may have relative adrenocortical insufficiency, although not all studies confirm this finding. Corticosteroids play an important role in controlling excessive immune response, and they may reduce the severity of organ dysfunction in critical illness. In this prospective study, we investigated the incidence of adrenal insufficiency in severe sepsis and its relation to the development of multiple organ failure.

METHODS

Forty-one patients meeting the criteria for severe sepsis were studied. A short ACTH stimulation test was carried out within 24 h of the diagnosis of sepsis. Peak serum cortisol level < 680 nmol/L and a rise of less than 260 nmol/L were used as the criteria for relative adrenocortical insufficiency.

RESULTS

Relative adrenocortical insufficiency was detected in six patients. Duration of the ICU stay (P = 0.002) and mechanical ventilation (P = 0.024) were significantly longer in patients with impaired adrenal function. In the survivors, SOFA scores were significantly higher in patients with impaired adrenal function. The plasma ACTH levels were normal in most of the patients with relative adrenal insufficiency, whereas most patients with normal adrenal function had extremely low plasma ACTH levels.

CONCLUSION

The ICU stay was longer and multiple organ failure more severe in patients with impaired adrenocortical function. There was a clear dissociation between ACTH and cortisol levels in AAR patients. This finding suggests that the integrity of the hypothalamic-pituitary-adrenal axis may be impaired in severe sepsis.

The International Sepsis Forum's controversies in sepsis: corticosteroids should not be routinely used to treat septic shock

Corticosteroid treatment of severe sepsis has been one of the most controversial clinical issues in critical care. In fact, few agents can claim to have been evaluated in scores of studies spanning 3-4 decades. Yet, convincing proof that corticosteroids are useful pharmacologic agents in the treatment of this major clinical problem remains elusive. Recently, interest has resurfaced but this time the focus is on a steroid replacement approach for what has now been termed "relative adrenal insufficiency" rather than relying on the pharmacologic effects of steroids. This route holds promise, but proof remains lacking.

The hypothalamic-pituitary-adrenal response to critical illness

The maintenance of life depends on the capacity of the organism to sustain its equilibrium via allostasis'-the ability to achieve stability through change. Life-threatening disease induces acute adaptive responses specific to the stimulus and generalized responses when the disturbances are prolonged. These changes are associated with increased activity of the hypothalamic-pituitary-adrenal axis and may have survival value in preparing the body for fight or flight'. There is a shift towards an increase in glucocorticoid production and away from mineralocorticoid and androgen production, as well as an increase in the biological effects of glucocorticoids through an increased cortisol free fraction and an increased glucocorticoid receptor sensitivity. During the prolonged phase, there is a dissociation between high plasma cortisol and low adrenocorticotropin hormone levels, suggesting non-adrenocorticotropin hormone-mediated mechanisms for the regulation of the adrenal cortex. This hypercortisolism is in contrast to the very low dehydroepiandrosterone sulphate level, indicating an imbalance between the immunostimulatory and immunosuppressive adrenocortical hormones. The question is whether the total serum cortisol concentration represents sufficient glucocorticoid biological activity during the prolonged phase of critical illness.

Relative adrenal failure in intensive care: an identifiable problem requiring treatment?

Adequate adrenocortical function is essential to survive critical illness. Most critically ill patients display an elevated plasma cortisol level, reflecting activation of the pituitary-adrenal axis, which is considered to be a homeostatic adaptation. In the setting of critical illness, the failure of an appropriate neuroendocrine response can lead to the picture of vasopressor-dependent refractory hypotension. This state of relative or functional adrenal insufficiency is characterized by an inadequate production of cortisol in relation to an increased demand during periods of severe stress, particularly prolonged critical illness such as multi-organ failure. This clinical entity, however, lacks clear-cut diagnostic criteria. What are the appropriate cortisol concentrations in the critically ill? Should base-line and adrenocorticotropic hormone-stimulated cortisol concentrations be assessed? The classical adrenocorticotropic hormone stimulation test is often used, but there are problems with interpreting its results. Other diagnostic tools, such as the low-dose adrenocorticotropic hormone test and relative eosinophilia, are promising but also lack proper criteria. A prompt response to hydrocortisone treatment is a major clue to the diagnosis. Recent studies with stress doses of hydrocortisone in sepsis and septic shock have shown a marked haemodynamic improvement, but whether patients with relative adrenal dysfunction benefit most from this treatment and whether there is definitely an effect on outcome is still undecided.

Hypopituitarism after surgical clipping of a ruptured cerebral aneurysm

OBJECTIVE

The causes of hypopituitarism in adult life are most frequently cerebral tumors, pituitary infarction, head trauma, pituitary surgery, or irradiation. We report a case of hypopituitarism after surgical clipping of a ruptured cerebral aneurysm. Two previous cases after the rupture of a cerebral aneurysm have been reported.

DESIGN

Case report.

PATIENTS

One 42-yr-old man.

MEASUREMENTS AND MAIN RESULTS

A 42-yr-old man was admitted as an emergency for unconsciousness. The computed tomography showed a massive subarachnoid hemorrhage, and specific angiography showed an aneurysm in the internal carotid. The aneurysm was successfully clipped through craniotomy. The patient's hospital course was marked by a few episodes of pulmonary infection, and a tracheotomy was performed. The patient was transferred to the rehabilitation unit; he received a rating of 9 on the Glasgow Coma Scale. Seven months after rupture of the aneurysm, the patient was readmitted to the intensive care unit for septic shock, with pulmonary infection associated with vomiting and diarrhea. Despite standard therapy and inotropic support, there was no improvement of his clinical condition. Adrenal failure was then suspected. Treatment was started immediately with hydrocortisone (50 mg) four times a day. Within hours, his clinical condition improved. The following month, the patient was weaned off his tracheotomy and had nearly recovered. Endocrine tests confirmed the cortisol insufficiency but also hypothyroidism and hypogonadotropic hypogonadism secondary to hypopituitarism.

CONCLUSION

Our case is the first one reported of hypopituitarism after surgical clipping of a ruptured cerebral aneurysm.

Adrenal insufficiency in critically ill emergency department patients: a Taiwan preliminary study

OBJECTIVE

Unrecognized adrenal insufficiency can have serious consequences in critically ill emergency department (ED) patients. This prospective pilot study of adrenal function in patients with severe illness was undertaken to determine the prevalence of adrenal dysfunction and any relation to prior herbal drug use.

METHODS

In a high-volume urban tertiary care ED, adult patients with sepsis or acute myocardial infarction (AMI) were eligible for the study. Over a two-month period, a convenience sample was enrolled by the authors on arrival to the ED. Inclusion criteria were systemic inflammatory response syndrome (SIRS) criteria plus evidence of at least one organ dysfunction or cardiac marker plus electrocardiogram-proven AMI. Exclusion criteria included known corticosteroid use. Serum cortisol was measured on arrival and for those patients with a level of <15 microg/dL (<414 nmol/L), an adrenocorticotropic hormone (ACTH) stimulation test was performed.

RESULTS

Of the 30 enrolled patients, 23 (77%) were suffering from severe sepsis and the other seven (23%) had an AMI. Thirteen of the 30 patients (43%; 95% CI = 25% to 65%) had serum cortisol levels of <15 microg/dL, consistent with adrenal insufficiency, nine with severe sepsis and four with an AMI. Eight (62%; 95% CI = 32% to 86%) of the 13 patients with low cortisol levels reported using herbal medications, while only two (12%; 95% CI = 1% to 36%) of the 17 with normal cortisol levels reported taking herb drugs (p = 0.01). Only two (15%; 95% CI = 2% to 45%) of the patients with low cortisol levels failed their corticotropin stimulation test, suggestive of true adrenocortical insufficiency. Both reported using herbal preparations.

CONCLUSIONS

These results indicate that adrenal dysfunction is common among a group of critically ill patients seen in this Taiwanese ED. Moreover, the use of herbal drugs was high in the patients with low serum cortisols. Further studies are required to both confirm these findings and clarify whether a number of herbal medications contain corticosteroids.

Adrenal insufficiency during the late stage of polymicrobial sepsis

OBJECTIVES

Although studies have indicated that adrenal insufficiency occurs after severe trauma and hemorrhagic shock, it remains controversial whether adrenal function is depressed during the late stage of polymicrobial sepsis.

DESIGN

Prospective, controlled animal study.

SETTING

A university research laboratory.

SUBJECTS

Male rats (275-325 g) were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP) or sham operation followed by the administration of normal saline solution.

MEASUREMENTS AND MAIN RESULTS

Systemic blood samples were taken at 20 hrs after CLP (i.e., a late stage of sepsis) or sham operation to measure plasma levels of corticosterone and corticotropin as well as adrenal contents of corticosterone. Additional groups of animals were utilized to examine corticotropin-stimulated plasma corticosterone release as well as adrenal levels of cyclic adenosine monophosphate (cAMP, the second messenger of corticotropin action). The results indicate that despite a 75% (p < .05) higher concentration in plasma corticotropin at 20 hrs after the onset of sepsis, plasma corticosterone levels were similar to those in sham-operated animals. In addition, adrenal contents of corticosterone were reduced by 42% (p < .05) in septic animals. Moreover, the plasma corticosterone and adrenal cAMP responses to corticotropin were reduced by 53% and 27% (p < .05), respectively, at 20 hrs after CLP.

CONCLUSIONS

These findings suggest that, despite high plasma levels of endogenous corticotropin, adrenal dysfunction, as indicated by the reduction of corticotropin-induced plasma corticosterone release and adrenal contents of cAMP as well as the decreased adrenal levels of corticosterone, occurs during the late stage of polymicrobial sepsis. Therefore, the recognition of adrenal insufficiency and interventions to improve adrenal responsiveness may be beneficial in improving the outcome during late sepsis.

Adrenocortical response and cortisone replacement in systemic inflammatory response syndrome

The use of steroids as an adjunct to antimicrobial therapy has been controversial for many decades. Recent reports of the use of steroids in supraphysiological rather than in "industrial" doses in patients with sustained circulatory instability has re-ignited the debate. Anecdotal reports of adrenal insufficiency in septic patients have suggested a relative cortisol deficiency in these patients with poor survival if not given supplementary steroids. The possibility that the hypothalamic pituitary adrenal axis is intimately involved in the pathogenesis of this entity has not previously been highlighted. This review looks at the relationship of sustained cytokine release and the possibility of altering the stress response with progressive loss of adrenocorticotrophic hormone release and subsequent diminution in adequate cortisol levels. The reliance on, and misinterpretation of, the short synacthen test in diagnosing the possibility of this condition is emphasized.

Adrenal insufficiency in high-risk surgical ICU patients

STUDY OBJECTIVES

To examine the incidence and response to treatment of adrenal insufficiency (AI) in high-risk postoperative patients.

DESIGN

Prospective observational case series.

SETTING

Large urban tertiary-care surgical ICU (SICU).

PARTICIPANTS

Adults > 55 years of age who required vasopressor therapy after adequate volume resuscitation in the immediate postoperative period.

INTERVENTIONS

Each patient underwent a cosyntropin (ACTH) stimulation test; at the discretion of the clinical team, some patients were empirically given hydrocortisone (100 mg IV q8h for three doses) before serum cortisol values became available.

MEASUREMENTS

Adrenal dysfunction (AD), defined as serum cortisol < 20 microg/dL at all time points, with Delta cortisol (60 min post-ACTH minus baseline) of < or = 9 microg/dL; functional hypoadrenalism (FH), defined as serum cortisol < 30 microg/dL at all time points or Delta cortisol (60 min post-ACTH minus baseline) < or = 9 microg/dL; and AI, as the presence of either AD or FH.

RESULTS

One hundred four patients were enrolled with a mean age (SD) of 65.2 +/- 16.9 years. AI (AD plus FH) was found in 34 of 104 patients (32.7%): AD was found in 9 patients (8.7%), FH in 25 patients (24%), and normal adrenal function in 70 patients (67.3%). The absolute eosinophil count was significantly higher in the combined AD and FH groups compared with the group with normal adrenal function (p < 0.05). Forty-six of 104 patients (44.2%) received hydrocortisone; 29 (63%) could be weaned from treatment with vasopressors within 24 h. This beneficial effect of hydrocortisone reached statistical significance in the FH group when compared with untreated patients (p < 0.031); a similar trend was seen in the AD group (p = 0.083). Mortality was also lower in the hydrocortisone-treated AI patients (5 of 23 [21%] vs 5 of 11 [45%] in those not receiving hydrocortisone; p < 0.01).

CONCLUSION

There is a high incidence of AI among SICU patients > 55 years of age with postoperative hypotension requiring vasopressors. There is also a significant association between hydrocortisone replacement therapy, resolution of vasopressor requirements, and improved survival.

The hypothalamic-pituitary-adrenal axis of patients with severe sepsis: altered response to corticotropin-releasing hormone

OBJECTIVE

To investigate the functional integrity of the hypothalamic-pituitary-adrenal (HPA) axis in patients with severe sepsis by stimulating with corticotropin-releasing hormone (CRH).

DESIGN

Prospective observational study in consecutive intensive care unit patients with severe sepsis.

SETTING

Surgical intensive care unit and outpatient department of endocrinology in a university hospital.

PATIENTS

The study included 20 patients with the diagnosis of severe sepsis; six critically ill, nonseptic patients after major surgery; ten patients with primary adrenal insufficiency; ten patients with anterior pituitary insufficiency; and ten individuals without clinical signs of HPA axis disturbance.

INTERVENTIONS

CRH tests were performed with an intravenous bolus injection of 100 microg of human CRH.

MEASUREMENTS AND MAIN RESULTS

We studied the functional integrity of the HPA axis in patients with severe sepsis by performing the CRH test. In addition, during the period of severe sepsis, we repeatedly measured basal plasma concentrations of adrenocorticotropin hormone (ACTH) and cortisol. The mean basal plasma cortisol concentration was decreased significantly in nonsurvivors with severe sepsis (288.8 +/- 29.1 [sem] nmol/L) compared with survivors (468.1+/- 18.6 nmol/L; p <.01). By calculating the ACTH/cortisol indices, we found no evidence for adrenal insufficiency in patients with severe sepsis. The mean ACTH/cortisol indices of nonsurvivors with severe sepsis (0.02 +/- 0.008) and survivors (0.01 +/- 0.002) were significantly lower compared with the index of patients with primary adrenal insufficiency (6.8 +/- 1.0; p <.001). In contrast, in nonsurvivors with severe sepsis, the plasma cortisol response to CRH stimulation was impaired compared with survivors: The mean basal cortisol concentration within the CRH test was 269.4 +/- 39.8 nmol/L in nonsurvivors compared with 470.8 +/- 48.4 nmol/L in survivors and increased to a peak value of 421.6 +/- 72.6 nmol/L in nonsurvivors and 680.7 +/- 43.8 nmol/L in survivors (p <.02). However, the change in plasma cortisol, expressed as mean +/- sem and calculated by subtracting the basal cortisol from the peak cortisol after CRH stimulation, was not significantly different in survivors with severe sepsis (243.5 +/- 36.1, range 111.0-524.0 nmol/L, n = 15) compared with nonsurvivors (161.0 +/- 38.9, range 42.0-245.0 nmol/L, n = 5; p >.05).

CONCLUSIONS

We found lower basal plasma cortisol concentrations in nonsurvivors compared with survivors of severe sepsis. In addition, the plasma cortisol response to a single CRH stimulation was impaired in nonsurvivors compared with survivors. Reduced responses to CRH stimulation may reflect a state of endocrinologic organ dysfunction in severe sepsis.

Adrenal insufficiency masquerading as sepsis in a patient with tetraparesis: a case report

Several endocrine changes have been reported in patients with tetraplegia after spinal cord injury (SCI). These changes should be considered when prescribing medications that influence the endocrine pathways. Megestrol acetate has gained acceptance as a way to promote weight gain in cachectic patients without significant adverse effects. We present a case of a 51-year-old man with C5-C6 tetraparesis who was only 67% of his ideal body weight and was placed on megestrol acetate 5 months before admission for a urologic procedure. Postoperatively, the patient had severe hypotension and tachycardia that was interpreted as a septic or cardiac event. Further workup revealed subnormal levels of 8AM cortisol. An adrenocorticotrophic hormone stimulation test demonstrated results consistent with adrenal suppression. Hydrocortisone supplementation was started, and 6 months later cortisol levels were within normal limits. Cachexia, hypotension, and mild tachycardia are not uncommon in patients with SCI. When severe hypotension and tachycardia are seen in patients with tetraplegia, the diagnosis of adrenal insufficiency should be considered.

Adrenocortical function in critically ill patients 24 h after a single dose of etomidate

We compared the effects of single doses of etomidate and thiopentone on adrenocortical function in a randomised controlled clinical trial involving 35 critically ill patients who needed a general anaesthetic. Just before induction of anaesthesia, a baseline blood cortisol sample was taken. Twenty-four hours later we performed a short adrenocorticotrophic hormone stimulation test. No patient had a low cortisol level (< 160 nmol.l-1) at any time during the study. Baseline, pre-ACTH and post-ACTH cortisol levels were similar in the two groups. However, significantly more patients in the etomidate group had an ACTH-stimulated cortisol increment < 200 nmol.l-1. The clinical significance of these findings is not clear, but we conclude that single doses of etomidate may interfere with cortisol synthesis for at least 24 h in the critically ill.

Endocrinologic and metabolic complications in the intensive care unit

Critical illness provides major stresses on all body systems, including those serving important regulatory functions. Endocrinologic and metabolic abnormalities are common on presentation and during hospitalization in the intensive care unit. Some of these abnormalities are the focus of this article. The authors review abnormalities of the adrenal and thyroid glands and in the metabolism of glucose, and include a brief review of abnormalities of sodium and calcium metabolism.

Adrenocortical function in patients with ruptured aneurysm of the abdominal aorta

OBJECTIVE

To investigate adrenocortical function in patients with ruptured aneurysm of the abdominal aorta.

DESIGN

Prospective clinical investigation.

SETTING

Surgical intensive care unit in a university teaching hospital and intensive care unit in a general hospital.

PATIENTS AND PARTICIPANTS

54 patients with a documented rupture of the abdominal aorta.

INTERVENTIONS

A short adrenocorticotrophic hormone (ACTH) stimulation test was performed.

MEASUREMENTS AND RESULTS

Patients were studied within 24 h of admission to the hospital. Blood samples for the measurement of cortisol and ACTH were collected at 0800 h. Subsequently 0.25 mg tetracosactrin (Synacthen) was injected i.v. and after 60 min cortisol measurement was repeated. The criterion for a normal short ACTH test was: stimulated or unstimulated cortisol levels > or = 0.55 mumol/l. For the group as a whole, an unstimulated plasma cortisol level of 0.76 mumol/l was comparable to that in other groups of critically ill patients with similar severity of illness. Between survivors and non survivors, significant differences were found between unstimulated plasma cortisol levels (0.70 vs 1.03 mumol/l), stimulated plasma cortisol levels (1.00 vs 1.30 mumol/l), and plasma ACTH levels (72 vs 133 ng/l). One patient did not meet the criteria for normal adrenocortical function: unstimulated plasma cortisol 0.26 mumol/l, stimulated plasma cortisol 0.47 mumol/l.

CONCLUSIONS

In the patients studied with ruptured aneurysm of the abdominal aorta, adrenocortical response was comparable to that in other groups of critically ill patients with similar severity of illness. High cortisol levels were associated with mortality. One patient did not meet the criteria for normal adrenocortical function but survival without steroid treatment.

Persistent endocrine stress response in patients undergoing cardiac surgery

To investigate the endocrine stress response in patients undergoing major surgery with general anesthesia using a balanced technique with sufentanil, isoflurane and midazolam up to the second postoperative day, blood levels of cortisol, epinephrine, norepinephrine, prolactin and growth hormone were determined in 68 males for elective coronary artery bypass grafting (CABG) surgery. Intraoperatively, during extracorporeal circulation none of the measured parameters were significantly increased compared to preoperative values. The endocrine response of patients with perioperative epinephrine medication (n = 32) was not significant different to patients that did not receive exogenous epinephrine (n = 36). On the evening of the day of surgery, levels of cortisol (3 fold), epinephrine (4.7 fold), norepinephrine (1.7 fold) and growth hormone (16.5 fold) were significantly increased. Compared to preoperative values levels of cortisol (3.3 fold), growth hormone (5.5 fold) and norepinephrine (1.8 fold) remained elevated up to the evening of the second postoperative day. In conclusion, the endocrine stress response in patients undergoing CABG-surgery under general anesthesia with sufentanil, midazolam, isoflurane is intraoperatively prevented by anesthesia. Although hemodilution or hormone degradation might be responsible for the lack of an increase in endocrine parameters during CPB, this study indicates that a balanced technique with isoflurane, sufentanil and midazolam is more effective in blocking the endocrine stress response than previously described anesthetic techniques. In the early postoperative period, a sharp increase in cortisol, epinephrine, norepinephrine and growth hormone occurred suggesting that the predominant endocrine stress response begins in the intensive care unit with end of anesthesia. The postoperative elevated levels of cortisol, growth hormone and norepinephrine indicate a persisting stress-response for more than two days after surgical trauma.

Postoperative dissociation of blood levels of cortisol and adrenocorticotropin after coronary artery bypass grafting surgery

The regulation of the hypothalamo-pituitary-adrenal (HPA) axis in the operative and perioperative period of major surgical procedures is necessary for successful adaption to surgical stress. We report evidence on an altered response of HPA axis regulation in patients who underwent coronary artery bypass grafting (CABG) surgery. Plasma levels of adrenocorticotropin (ACTH), beta-endorphin, and cortisol were determined with radio-immune assay in 50 males for elective CABG surgery. The patients received general anesthesia using a balanced technique with sufentanil, isoflurane, and midazolam. Pre- and intraoperatively, there was no significant increase in plasma cortisol, ACTH, and beta-endorphin levels. On the evening of surgery, all plasma hormone levels were increased. On the evening of the first and second postoperative day, plasma ACTH and beta-endorphin levels returned to the preoperative baseline values. During the same time interval, plasma cortisol levels were significantly elevated and remained high until the end of the study period (p < 0.001). Our results indicate an altered regulation of the HPA axis in the postoperative period of patients after CABG surgery, as they are compatible with similar results in patients after major abdominal surgery, burned patients, and critically ill patients. Therefore, it is assumed that the finding of a postoperative dissociation between ACTH and cortisol is a result of the severity of perioperative adaptive mechanisms rather than of the specific conditions related to cardiac surgery.

Blunted cortisol response after administration of corticotropin releasing hormone in endotoxemic dogs

To evaluate the effects of a standard inflammatory challenge on the dynamics of the hypothalamic-pituitary-adrenal (HPA) axis, we studied the effects of low-dose endotoxin (1.0 microgram/kg) on plasma adrenocorticotropic hormone (ACTH) and cortisol concentrations in a saline-controlled study in five awake dogs. Four hours after endotoxin or saline challenge human corticotrophin-releasing hormone (hCRH; 1.0 microgram/kg) was administered. Plasma ACTH and cortisol levels increased considerably in response to endotoxin, from 13 +/- 1 ng/l to 360 +/- 85 ng/l (p < 0.01) and from 60 +/- 20 nmol/l to 710 +/- 80 nmol/l (p < 0.01). Despite a considerable difference in ACTH and cortisol levels prior to CRH administration between both studies (p < 0.01), the absolute increase in ACTH levels induced by hCRH was not different (231 +/ 43 ng/l vs 238 +/- 45 ng/l, control vs endotoxin). Plasma cortisol levels increased significantly in the control study (from 40 +/- 10 nmol/l to 330 +/- 40 nmol/l, p < 0.01), whereas they did not change in the endotoxin study after hCRH administration (from 710 +/- 80 nmol/l to 730 +/- 70 nmol/l, ns). We conclude that the HPA-axis reacts initially to endotoxin in such a way that cortisol, but not ACTH, secretion is maximized. Therefore, a blunted cortisol response to CRH testing is part of the initial response to infection.

Adrenal insufficiency in the surgical intensive care unit patient

BACKGROUND

Adrenocortical dysfunction is unusual in the unselected critically ill patient. Case reports document a state of corticosteroid responsive vasopressor dependence, resembling the systemic inflammatory response syndrome. The exact incidence of this disorder is unknown.

METHODS

We prospectively studied the incidence of adrenal insufficiency during a 9-month period in a surgical intensive care unit (ICU) population. Trauma, general surgery, urology, and gynecologic-oncology patients were included. Patients who met criteria were given a cosyntropin stimulation test.

RESULTS

Overall, the incidence of adrenal insufficiency was 0.66%. In the subgroup of patients with greater than 14 days stay in the ICU, 6% were found to have adrenal insufficiency. In patients aged more than 55 years and with ICU stays of 14 days or greater, 11% were adrenally insufficient.

CONCLUSIONS

Screening of critically ill patients for adrenal insufficiency, particularly those with prolonged ICU stay and age greater than 55 years, is warranted.

Temperature-induced down-regulation of the glucocorticoid receptor in peripheral blood mononuclear leucocyte in patients with sepsis or septic shock

OBJECTIVE

Activation of the hypothalamic-pituitary-adrenal axis is of vital importance during critical illness. We have studied the adaptive mechanisms which occur at the level of the glucocorticoid receptor in glucocorticoid target tissues in patients with sepsis or septic shock.

DESIGN

The effects of hypercortisolaemia, hyperthermia and cellular composition on number of glucocorticoid receptors per cell and their affinity were evaluated, both in vitro and in vivo, in peripheral blood mononuclear leucocytes of control subjects and in patients with sepsis or septic shock.

SUBJECTS

Fifteen patients (age 25-79) with sepsis or septic shock who were admitted to an intensive care unit were studied. The control group consisted of 24 healthy laboratory employees.

MEASUREMENTS

The binding capacity and affinity of the glucocorticoid receptors were measured and compared to clinical data and the plasma cortisol concentrations.

RESULTS

Hypercortisolaemia, in vitro, resulted in a decreased affinity and a decreased binding capacity of the glucocorticoid receptor. In vitro, hyperthermia as well as variations in the cellular composition did not influence the glucocorticoid receptor. In vivo, there was no change in the number of receptors per cell in patients with sepsis or septic shock as compared to healthy controls. However, a decreased affinity of the glucocorticoid receptor was observed. There was a weak but significant negative correlation between body temperature and the number of glucocorticoid receptors in the patient group. There was no relation between circulating cortisol concentrations and glucocorticoid receptor affinity and number.

CONCLUSIONS

There is no obvious regulation of the number of glucocorticoid receptors by plasma cortisol concentrations in vivo. The decreased affinity of the glucocorticoid receptor together with the negative correlation between hyperthermia and the number of glucocorticoid receptors in patients with sepsis or septic shock suggest that hypothalamic-pituitary-adrenal axis activation during critical illness is accompanied by peripheral adaptation in glucocorticoid receptor number and affinity.

Pituitary-adrenal axis function in systemic inflammatory response syndrome

This study characterizes the hypothalamic-pituitary-adrenal axis function in patients with sepsis syndrome now known as systemic inflammatory response syndrome (SIRS). One hundred and thirteen patients with SIRS had their pituitary-adrenal axis tested with the use of a 250 µg IV ACTH stimulation test. No patient received corticosteroids prior to the ACTH stimulation test. Serum cortisol concentrations were measured prior to and 30 and 60 min after ACTH administration. 26% of the patients had bacteremia, 22% bacteruria, 22% AIDS, 17% renal failure, 15% diabetes, 13% severe liver disease, 8% GI bleed, 4% pancreatitis, 3% trauma and 1% classical Addison's disease. Several patients had more than one disorder. The overall mortality was 28%. Multivariate analysis identified that both the baseline cortisol concentration and delta cortisol concentration were significant indicators of mortality. Despite the fact that mortality was double in the bacteremic patients, the baseline cortisol concentrations were similar to the non-bacteremic patients (25.4 ± 1.9vs 25.1 ± 2.5 µg/dl). The only cortisol abnormality noted in the bacteremic patients was a significantly smaller delta cortisol response to ACTH (14.7 ± 2.2vs 18.9 ± 1.2 µg/dl;P<0.05). These data imply that bacteremic processes may alter the adrenal responsiveness to intravenous ACTH administration. Understanding the pathophysiological disturbances responsible for an impaired adrenal reserve may identify new treatment strategies for patients with bacteremia.

The endocrine response to critical illness

The endocrine response to stress is complex. Elevations in the serum concentrations of the "classic" stress hormones, epinephrine and cortisol, occur following many kinds of physiologic challenge and are accompanied by elevations in corticotropin, GH, and glucagon levels. These changes are probably responsible for the hyperglycemia and hypercatabolism common to most critical illness. If volume depletion is present, vasopressin, renin, and aldosterone secretion are also likely to be stimulated. These hormones, if present in excess, may produce fluid retention and hyponatremia. In some critically ill patients, there is a dissociation of renin and aldosterone production called hyperreninemic hypoaldosteronism, but the clinical importance of this syndrome is poorly understood. Thyroid hormone metabolism is commonly affected by critical illness, which results in characteristic abnormalities of thyroid function testing known as the euthyroid sick syndrome. The reproductive axis is exquisitely sensitive to physiologic stress; hypogonadotropic hypogonadism is a common finding in critical illness. The ongoing challenge to the clinician is to determine whether seemingly abnormal hormone measurements in critically ill patients reflect an appropriate homeostatic response to severe illness or, instead, whether they denote an independent metabolic disorder that might actually cause or contribute to the patient's unstable condition. In view of the exceedingly complex (and poorly understood) interactions involved in the human response to a severe illness, a thoughtful approach to the whole patient is essential and far preferable to indiscriminate hormone testing. Such testing, at best, may be uninterpretable in light of the clinical circumstances or, at worst, may lead to therapeutic misadventures.

Adrenocortical function during septic shock

OBJECTIVE

To investigate, in patients with severe septic shock, the adrenocortical function assessed by daily plasma cortisol determinations during the first 72 h and by the short synthetic ACTH stimulation test performed within 24 h of the onset of shock.

DESIGN

Prospective clinical investigation.

SETTING

Medical intensive care unit in a university teaching hospital.

PATIENTS

40 consecutive patients with documented septic shock requiring at least hemodynamic resuscitation and respiratory support.

INTERVENTIONS

There were no interventions.

MEASUREMENTS AND RESULTS

Basal cortisol concentrations were increased with a mean value of 36.8 micrograms/dl (range 7.9-113). Of the overall cortisol determinations 92% were above 15 micrograms/dl. No statistically significant differences in basal cortisol concentrations were found when survival, type of infection, and positive blood cultures were considered. Patients with hepatic disease had significantly higher cortisol (50.1 (+/- 6.2) micrograms/dl versus 35.9(+/- 3.3) micrograms/dl, p = 0.035) levels compared to other patients. No correlations were found between basal plasma cortisol concentrations and factors such as SAPS, OSF, hemodynamic measurements, duration of shock, and amount of vasopressor and/or inotropic agents. Cortisol concentrations had significant but weak correlation with ACTH levels in survivors (r = 0.4; p = 0.03; n = 28) but not in non-survivors (r = 0.03; p = 0.85; n = 52). Cortisol levels in non-survivors increased significantly from enrollment time to the 72nd hour of the survey (day 1: 38.9(+/- 3.8) micrograms/dl versus day 3: 66.7(+/- 17.1) micrograms/dl; p = 0.046) and were significantly higher than those recorded in survivors. Responses to the short ACTH stimulation test were not significantly different between survivors and non-survivors. According to the different criteria used to interpret the response to the ACTH stimulation test, incidence of adrenocortical insufficiency was highly variable ranging from 6.25-75% in patients with septic shock. Only one patient had absolute adrenocortical insufficiency (basal cortisol level below 10 micrograms/dl; response to the ACTH stimulation test below 18 micrograms/dl).

CONCLUSION

Our data suggest that in a selected population of patients with severe septic shock single plasma cortisol determination has no predictive value. The short ACTH stimulation test performed within the first 24 h of onset shock can neither predict outcome nor estimate impairment in adrenocortical function in patients with high basal cortisol level. Adrenal insufficiency is rare in septic shock and should be suspected when cortisol level is below 15 micrograms/dl and then confirmed by a peak cortisol level lower than 18 micrograms/dl during the short ACTH stimulation test.

Prediction of outcome in intensive care patients using endocrine parameters

OBJECTIVE

To determine the ability of various endocrine parameters, measured at the time of intensive care unit (ICU) admission, to predict patient outcome.

DESIGN

Prospective, cohort study of patients requiring intensive care.

SETTING

The medical/surgical ICU at South Cleveland Hospital, UK and a medical/surgical ICU in a UK district hospital.

PATIENTS

A total of 260 consecutive patients requiring intensive care over a 2-yr period.

INTERVENTIONS

Patients were investigated within 1 hr of ICU admission by measuring plasma cortisol, serum thyroxine, triiodothyronine, and thyrotropin concentrations and by obtaining the Acute Physiology and Chronic Health Evaluation (APACHE II) score. Individual variables were compared between survivors and nonsurvivors.

MEASUREMENTS AND MAIN RESULTS

There were significant differences for each endocrine parameter between survivors and nonsurvivors (all p < .01). A multiple logistic regression analysis showed that only thyroxine, thyrotropin, and cortisol concentrations were independent predictors of outcome. An equation using these variables predicted outcome with 82% accuracy at the 0.5 cutoff point of the receiver operating curve. APACHE II scores predicted outcome with 72% accuracy at the same point on the receiver operating curve. Correct prediction of death was more frequent with the Endocrine Index than with APACHE II scores. Overall predictive power of the Endocrine Index, as measured by the area under the receiver operating curve, was 0.94 (95% confidence interval 0.91 to 0.96) vs. 0.85 (95% confidence interval 0.81 to 0.89) for APACHE II scores. Combining APACHE II scores and the endocrine parameters in a single index did not improve prediction (area under receiver operating curve = 0.94).

CONCLUSION

An endocrine prognostic index based on ICU admission measurements of thyroxine, thyrotropin, and cortisol concentrations is a superior discriminator of patient outcome than the APACHE II score.

Hypocortisolaemia and adrenocortical responsiveness at onset of septic shock

OBJECTIVE

To characterise the plasma cortisol profile and adreno-cortial responsiveness (short Synacthen test) of patients in septic shock.

DESIGN

Retrospective assessment using case-notes and ICU charts.

SETTING

University teaching hospital ICU.

PATIENTS

68 septic shock patients with plasma cortisol and/or short Synacthen test measured at ICU-admission or onset of shock post ICU-admission. Patients were identified from a total population of 155 patients who had PCL and/or SST measured over a 4.5 year period.

INTERVENTION

None.

MEASUREMENTS AND RESULTS

Patients with septic shock had a plasma cortisol ranging from 210-8900 nmol/l and mortality of 56%. There were 22 (32%) below (low) and 46 (68%) above (high) a 'critical' plasma cortisol of 500 nmol/l. Using stepwise logistic regression, mortality was adequately predicted by and increased with, increasing plasma cortisol and onset of shock remote from ICU-admission. Short Synacthen tests were available in 33 patients: 11 responders (cortisol increment > 200 nmol/l above baseline 30 min after 0.25 mg intravenous Synacthen) and 22 hypo-responders. Mortality in patients was adequately predicted by and increased with a decrease in cortisol increment post-Synacthen. Thirteen patients (plasma cortisol 606 +/- [SD] 297 nmol/l) had complete haemodynamic profiles before inotropic therapy; no relationship was demonstrated between plasma cortisol and circulatory variables. Follow-up revealed no cases of Addison's disease.

CONCLUSIONS

In septic shock, 'hypocortisolaemia' is not uncommon and does not predict a high mortality; adrenocortical hypo-responsiveness may be associated with poor outcome.