Search

Purpose: The aim of this study was to measure subcutaneous tissue cortisol obtained by microdialysis (MD) in 35 mechanically ventilated septic patients. Materials and Methods: Upon intensive care unit admission, an MD catheter was inserted into the subcutaneous tissue of the thigh. Cortisol (CORT) was determined in a 5:00 to 9:00 AM microdialysate sample collected within 72 hours. Concurrently, serum total (T-CORT) and free CORT (F-CORT) were measured. The Acute Physiology and Chronic Health Evaluation (APACHE II) and Sequential Organ Failure Assessment scores were calculated. Both T-CORT less than 10 μg/dL and F-CORT less than 0.8 μg/dL were considered as indicating critical illness-related corticosteroid insufficiency. Adrenal adequacy was defined as T-CORT greater than 20 μg/dL or F-CORT greater than 2.0 μg/dL. Results: Total CORT correlated significantly with F-CORT (rs=+0.8, P < .0001).Microdialysis CORT had a lower correlation with T-CORT (rs = +0.6, P < .0001) and F-CORT (rs = +0.7, P < .0001) and a weak correlation with APACHE II score (rs=+0.4, P < .01). On the basis of MD-CORT, the patients were divided in quartiles. Although the median F-CORT and T-CORT levels were significantly different (P < .001) among the MD-CORT quartiles, there was a considerable overlap between the subgroups. All patientswith T-CORT less than 10 μg/dL and all but 3 patients with F-CORT less than 0.8 μg/dL had tissue CORT in the lower quartile. However, only 50%and 58% of patients with adequate T-CORT and F-CORT levels, respectively, had concordant MD-CORT in the highest quartile. Conclusions: Microdialysis CORT levels correlate moderately with circulating T-CORT and F-CORT. Of note, several patients presented with discrepant measurements between interstitial and circulating CORT concentrations. Thus, interstitial CORT measurements represent an additional tool to investigate the tissue CORT availability in critically ill patients. [ABSTRACT FROM AUTHOR]

Objective: To assess whether adrenal cortex hormones predict ICU mortality in acute, mixed, critically ill patients.Design and Setting: Prospective study in consecutive intensive care patients in the general ICU of a teaching hospital.Patients: 203 severely ill patients with multiple trauma (n = 93), medical (n = 57), or surgical (n = 53) critical states.Measurements and Results: Within 24 h of admission in the ICU a morning blood sample was obtained to measure baseline cortisol, corticotropin (ACTH), and dehydropiandrosterone sulfate (DHEAS). Subsequently a low-dose (1 microg) ACTH test was performed to determine stimulated cortisol. The incremental rise in cortisol was defined as stimulated minus baseline cortisol. Overall, 149 patients survived and 54 died. Nonsurvivors were older and in a more severe critical state, as reflected by higher SOFA and APACHE II scores. Nonsurvivors had a lower incremental rise in cortisol (5.0 vs. 8.3 microg/dl and lower DHEAS (1065 vs. 1642 ng/ml) than survivors. The two groups had similar baseline and stimulated cortisol. Multivariate logistic regression analysis revealed that age (odds ratio 1.02), SOFA score (1.36), and the incremental rise in cortisol (0.88) were independent predictors for poor outcome.Conclusions: In general ICU patients a blunted cortisol response to ACTH within 24 h of admission is an independent predictor for poor outcome. In contrast, baseline cortisol or adrenal androgens are not of prognostic significance. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence and type of endocrine abnormalities in critical care patients with traumatic brain injury (TBI) and to examine their relationships to possible predisposing factors.Design: Prospective study.Setting: General intensive care unit in a university hospital.Patients and Participants: Thirty-four TBI patients (27 men, 7 women), having a mean age of 37+/-16 years, were studied after weaning from mechanical ventilation.Interventions: Baseline endocrine assessment was carried out by measuring cortisol, corticotropin, dehydroepiandrosterone sulfate, free thyroxine, thyrotropin (TSH), testosterone, oestradiol, follicle stimulating hormone (FSH), luteinizing hormone, prolactin, growth hormone and insulin-like growth factor I. Dynamic evaluation was performed by human corticotropin releasing hormone and growth hormone releasing hormone in all patients. Male patients underwent additional investigation with gonadotropin-releasing hormone. Severity of neurological derangement was graded according to Glasgow Coma Scale (GCS), Marshall Computerized Tomographic Classification and intracranial pressure (ICP) levels.Measurements and Results: Eighteen of the 34 patients (53%) had an abnormal result in at least one hormonal axis tested, with cortisol hyporesponsiveness and gonadal dysfunction being equally common, affecting 24% of patients. Endocrine abnormalities were associated with a higher brain CT-scan classification score ( p=0.02). The GCS on admission correlated positively with baseline FSH (r=0.37, p=0.03), peak FSH (r=0.41, p=0.03), testosterone (r=0.44, p=0.02) and TSH (r=0.39, p=0.03). There were no relations between ICP(max) and any baseline or dynamic hormone measurements.Conclusions: Patients with TBI receiving critical care show changes in their neuroendocrine responses, which depend upon clinical and radiological measures of head injury severity. Most common abnormalities include cortisol hyporesponsiveness and hypogonadism. [ABSTRACT FROM AUTHOR]

Abstract: Background: Reduced coronary velocity flow reserve (CFR) is associated with poor outcome in patients with cardiovascular disease. We investigated whether CFR is associated with tissue ischemia and acidosis, impaired myocardial deformation and adverse outcome in patients with septic shock. Methods: In 70 mechanically-ventilated patients with septic shock, we examined: a) S′ and E′ mitral annular velocities using tissue Doppler imaging (TDI), b) CFR of the left anterior descending artery after adenosine infusion using transesophageal Doppler echocardiography and c) lactate, pyruvate and glycerol in tissue by means of a microdialysis (MD) catheter inserted into the subcutaneous adipose tissue as markers of tissue ischemia and acidosis. SOFA and APACHE II prognostic scores and mortality in the intensive care unit (ICU) were recorded. Results: Reduced CFR, S′ and E′ as well as increased E/E′ correlated with increased SOFA, APACHE II and MD lactate to pyruvate ratio (p<0.05 for all correlations). Impaired TDI markers also correlated with increased MD glycerol (p<0.05). Reduced CFR correlated with decreased E′ (p<0.05). CFR was 1.8±0.42 in non-survivors (n=34) versus 2.08±0.44 in survivors (p=0.007). A CFR<1.90 predicted mortality with sensitivity of 70% and specificity of 69% (area under the curve 77%; p=0.003). CFR had an additive value to APACHE (chi-square change: 4.358, p=0.03) and SOFA (chi-square change: 3.692, p=0.04) for the prediction of mortality. Conclusion: Tissue ischemia and acidosis is a common pathophysiological link between decreased CFR and impaired LV myocardial deformation in septic shock. CFR is an additive predictor of ICU mortality to traditional risk scores in septic shock. [Copyright &y& Elsevier]