Dissociation between plasma adrenocorticotropin and serum cortisol level during the early postoperative period after gastrectomy

Evidence in Favor of an Alternative Glucocorticoid Synthesis Pathway During Acute Experimental Chagas Disease

It is well-established that infectious stress activates the hypothalamus-pituitary-adrenal axis leading to the production of pituitary adrenocorticotropin (ACTH) and adrenal glucocorticoids (GCs). Usually, GC synthesis is mediated by protein kinase A (PKA) signaling pathway triggered by ACTH. We previously demonstrated that acute murine Chagas disease courses with a marked increase of GC, with some data suggesting that GC synthesis may be ACTH-dissociated in the late phase of this parasitic infection. Alternative pathways of GC synthesis have been reported in sepsis or mental diseases, in which interleukin (IL)-1β, prostaglandin E2 (PGE2), and/or cAMP-activated guanine nucleotide exchange factor 2 (EPAC2) are likely to play a role in this regard. Accordingly, we have searched for the existence of an ACTH-independent pathway in an experimental model of a major parasitic disease like Chagas disease, in addition to characterizing potential alternative pathways of GC synthesis. To this end, C57BL/6 male mice were infected with T. cruzi (Tc), and evaluated throughout the acute phase for several parameters, including the kinetic of GC and ACTH release, the adrenal level of MC2R (ACTH receptor) expression, the p-PKA/PKA ratio as ACTH-dependent mechanism of signal transduction, as well as adrenal expression of IL-1β and its receptor, EPAC2 and PGE2 synthase. Our results reveal the existence of two phases involved in GC synthesis during Tc infection in mice, an initial one dealing with the well-known ACTH-dependent pathway, followed by a further ACTH-hyporesponsive phase. Furthermore, inflamed adrenal microenvironment may tune the production of intracellular mediators that also operate upon GC synthesis, like PGE2 synthase and EPAC2, as emerging driving forces for GC production in the advanced course of Tc infection. In essence, GC production seems to be associated with a biphasic action of PGE2, suggesting that the effect of PGE2/cAMP in the ACTH-independent second phase may be mediated by EPAC2.

Effect of parecoxib combined with thoracic epidural analgesia on pain after thoracotomy

BACKGROUND

Thoracotomy results in severe postoperative pain potentially leading to chronic pain. We investigated the potential benefits of intravenous parecoxib on postoperative analgesia combined with thoracic epidural analgesia (TEA).

METHODS

Eighty-six patients undergoing thoracic surgery were randomized into two groups. Patient-controlled epidural analgesia (PCEA) was used until chest tubes were removed. Patients received parecoxib (group P) or placebo (group C) intravenously just 0.5 h before the operation and every 12 h after operation for 3 days. The intensity of pain was measured by using a visual analogue scale (VAS) and recorded at 2, 4, 8, 24, 48, 72 h after operation. The valid number of PCA, the side effects and the overall satisfaction to analgesic therapy in 72 h were recorded. Venous blood samples were taken before operation, the 1(st) and 3(rd) day after operation for plasma cortisol, adrenocorticotropic hormone (ACTH), interleukin-6 and tumor necrosis factor-α level. The occurrence of residual pain was recorded using telephone questionnaire 2 and 12 months after surgery.

RESULTS

Postoperative pain scores at rest and on coughing were significantly lower with the less valid count of PCA and greater patient satisfaction in group P (P<0.01). Adverse effect and the days fit for discharge were comparable between two groups. The cortisol levels in placebo group were higher than parecoxib group at T2. The level of ACTH both decreased in two groups after operation but it was significantly lower in group P than that in group C. There were no changes in plasma IL-6 and TNF-α levels before and after analgesia at T1 and T2 (P>0.05). The occurrence of residual pain were 25% and 51.2% separately in group P and C 3 months postoperatively (P<0.05).

CONCLUSIONS

Intravenous parecoxib in multimodal analgesia improves postoperative analgesia provided by TEA, relieves stress response after thoracotomy, and may restrain the development of chronic pain.

The Effects of Different Anaesthetic Techniques on Surgical Stress Response During Inguinal Hernia Operations

OBJECTIVE

The aim of this study is to compare the effects of 3 different kinds of anaesthesia on stress response induced by surgery.

METHODS

Sixty patients aged between 25-70 American Society of Anesthesiologists (ASA) I-II group to undergo inguinal herniography were included in this study. Patients were randomly divided into 3 groups of 20. Group 1 received general anaesthesia with sevoflurane/air/remifentanil, patients in Group 2 received total intravenous anaesthesia (TIVA) with propofol/air/remifentanil and Group 3 received spinal anaesthesia induced by hyperbaric bupivacaine, adjoined by remifentanil sedation. Mean arterial pressure (MAP), heart rate and SpO2 values were recorded preoperatively, intraoperatively and postoperatively at certain periods. Cortisol, leptin and glucose levels were preoperatively detected. Intervals were as; 15 minutes prior to the induction of anaesthesia, at intraoperative first hour and at the postoperative third and twenty-forth hours.

RESULTS

MAP and heart rate values were similar in the inhalational anaesthesia and TIVA groups but relatively higher in the spinal anaesthesia group. Blood glucose levels were elevated, insulin levels were decreased in all groups, at the intraoperative first hour. Biphasic variation in blood leptin levels was observed in all groups, as the levels were lower than the preoperative control values at the intraoperative first and postoperative third hours and significantly higher at the postoperative twenty-forth hour. There was a significant decrease in cortisol level percentage change in the TIVA group at the intraoperative 1st hour, increasing in the other groups.

CONCLUSION

We concluded that TIVA supresses the stress response induced by surgery better by lowering cortisol levels, leading to a lower increase in blood glucose levels and a lower decrease in blood insulin levels when compared to others. Furthermore, leptin levels were increased at the postoperative twenty-forth hour. The lower increase at the postoperative twenty-forth hour in the TIVA group can be correlated with the anaesthetic agent.

Dissociation between ACTH and cortisol response in DEX-CRH test in patients with panic disorder

BACKGROUND

Panic disorder (PD) has been associated with the altered circadian rhythm of the hypothalamic-pituitary-adrenocortical (HPA) axis. The findings regarding the stress-specific functioning of the HPA-system are inconsistent. It is also unclear whether the HPA-system response after the Corticotropin-Releasing-Hormone (CRH) challenge becomes altered.

METHODS

For this study, the dexamethasone-corticotropin-releasing-hormone (DEX-CRH) test was implemented to assess the HPA-axis reactivity indicated by the plasma adreno-corticotropin-hormone (ACTH) and the cortisol release. The sample included 32 patients diagnosed with PD in a Structured Clinical Interview (SCID). Fourteen male and eighteen female patients, [mean age = 33.50 years, SD = 12.76] were matched with 32 healthy controls by age and gender. Moreover, a sample of patients with unipolar depression (n = 21, ten females) was examined as a clinical control group.

RESULTS

In healthy controls as well as in patients with PD and patients with unipolar depression, the ACTH and the cortisol response increased significantly due to the CRH injection after dexamethasone pre-treatment. There were differences between the healthy controls and the patients with PD in the plasma cortisol response pattern, however, not in the ACTH. The patients with PD showed a decreased CRH-induced plasma cortisol response. A median-split gave evidence that patients suffering from PD longer than two years showed a remarkably higher HPA-axis reactivity under CRH-injection than patients suffering from PD two years or less.

CONCLUSION

These findings provide strong evidence that patients with PD show some dissociation between ACTH and cortisol response under the DEX-CRH test with strong indicators that the length of the duration of the psychopathology is a risk factor for an increased reactivity of the HPA-axis in patients with PD.

Proven infection-related sepsis induces a differential stress response early after ICU admission

INTRODUCTION

Neuropeptides arginine-vasopressin (AVP), apelin (APL), and stromal-derived factor-1α (SDF-1α) are involved in the dysfunction of the corticotropic axis observed in septic ICU patients. Study aims were: (i) to portray a distinctive stress-related neuro-corticotropic systemic profile of early sepsis, (ii) to propose a combination data score, for aiding ICU physicians in diagnosing sepsis on admission.

METHODS

This prospective one-center observational study was carried out in a medical intensive care unit (MICU), tertiary teaching hospital. Seventy-four out of 112 critically ill patients exhibiting systemic inflammatory response syndrome (SIRS) were divided into two groups: proven sepsis and non sepsis, based on post hoc analysis of microbiological criteria and final diagnosis, and compared to healthy volunteers (n = 14). A single blood sampling was performed on admission for measurements of AVP, copeptin, APL, SDF-1α, adrenocorticotropic hormone (ACTH), cortisol baseline and post-stimulation, and procalcitonin (PCT).

RESULTS

Blood baseline ACTH/cortisol ratio was lower and copeptin higher in septic vs. nonseptic patients. SDF-1α was further increased in septic patients vs. normal patients. Cortisol baseline, ACTH, PCT, APACHE II and sepsis scores, and shock on admission, were independent predictors of sepsis diagnosis upon admission. Using the three first aforementioned categorical bio-parameters, a probability score for predicting sepsis yielded an area under the Receiver Operating Curve (ROC) curves better than sepsis score or PCT alone (0.903 vs 0.727 and 0.726: P = 0.005 and P < 0.04, respectively).

CONCLUSIONS

The stress response of early admitted ICU patients is different in septic vs. non-septic conditions. A proposed combination of variable score analyses will tentatively help in refining bedside diagnostic tools to efficiently diagnose sepsis after further validation.

Dissociation of ACTH and glucocorticoids

It is increasingly clear that significant differential regulation of pituitary and adrenal gland activation exists, leading to a dissociation of plasma adrenocorticotropic hormone and corticosteroid secretion during fetal, postnatal and adult life. An increasing number of preclinical and clinical studies report dissociation of adrenocorticotropic hormone and cortisol levels in critical illness, inflammation and mental disorders. Mechanisms involve an altered adrenal sensitivity, aberrant receptor expression or modulation of adrenal function by cytokines, vasoactive factors or neuropeptides. The degree of dissociation has been associated with the level of complications of sepsis, surgery, malignant disease and depression. The separation of adrenocorticotropic hormone and corticosteroid secretion is of clinical relevance and should be incorporated into our view on endocrine stress regulation.

Leptin and perioperative neuroendocrine stress response with two different anaesthetic techniques

BACKGROUND

Stress response to surgery is modulated by several factors, including magnitude of the injury, pain, type of procedure and choice of anaesthesia. Our purpose was to compare intra- and post-operative hormonal changes during total intravenous anaesthesia (TIVA) using propofol and remifentanil vs. sevoflurane anaesthesia in a low stress level surgical model (laparoscopy).

METHODS

We randomly allocated 18 patients undergoing laparoscopic surgery for benign ovarian cysts in two groups to receive either TIVA (group A=9) or sevoflurane anaesthesia (group B=9). Perioperative plasma levels of norepinephrine (NE), epinephrine (E), adrenocorticotropic hormone (ACTH), cortisol and leptin were measured. Blood samples were collected pre-operatively (time 0), 30 min after the beginning of surgery (time 1), after extubation (time 2), and 2 h (time 3) and 4 h after surgery (time 4).

RESULTS

The comparative analysis between the groups shows significantly higher values of NE (P<0.001 at time 1 and P<0.01 at time 3), E (P<0.001 at times 1 and 2; P<0.01 at time 3 and P<0.05 at time 4), ACTH (P<0.001 at times 1 and 2; P<0.05 at time 3) and cortisol (P<0.001 at times 1 and 2; P<0.01 at time 3; P<0.05 at time 4) in group B. The serum values of leptin were not significantly different between the two groups.

CONCLUSION

The choice of anaesthesia does not seem to affect the leptin serum levels but influences the release of stress response markers: ACTH, cortisol, NE and E.

Relationships between adrenocorticotropic hormone and cortisol are altered during clustered nursing care in preterm infants born at extremely low gestational age

BACKGROUND

Little is known about the effects of clustered nursing care on hypothalamic pituitary axis (HPA) responses in preterm infants in the neonatal intensive care unit.

AIMS

To examine facial responses, adrenocorticotropic hormone (ACTH) and cortisol levels, and the relationship between ACTH and cortisol in preterm infants in two gestational age groups (extremely low gestational age [ELGA: < or =28 weeks]; very low gestational age [VLGA: 29-31 weeks]) under basal conditions and in response to routine nursing procedures.

STUDY DESIGN

Within subjects' cross-over design in random order.

SUBJECTS

Ninety preterm infants with no postnatal steroid exposure were studied at 32+/-1 weeks postconceptional age.

OUTCOME MEASURES

Facial actions, ACTH and cortisol levels were measured after a 30 minute rest period and in response to routine clustered nursing care (CC). Changes in facial actions were analyzed using repeated measures ANOVA. MANOVA or Mann-Whitney U tests were used to determine differences in ACTH and cortisol between gestational age groups. Spearman rank correlations were used to examine relationships between perinatal variables and facial, ACTH and cortisol levels.

RESULTS

All infants had significantly increased facial responses to CC (p=0.001). Infants having experienced higher numbers of skin breaking procedures 24 h before basal assessment had higher basal cortisol levels (r=0.30, p=0.01). In response to CC, ELGA infants showed no correlation between ACTH and cortisol levels; VLGA infants showed a strong, positive correlation (r=0.62, p=0.02).

CONCLUSION

The pattern of relationship between ACTH and cortisol differs depending on gestational age at birth in response to clustered nursing care. Prior pain alters responsiveness and HPA dysregulation is apparent in ELGA infants.

Postoperative interleukin-6 and cortisol concentrations in elderly patients with postoperative confusion

OBJECTIVE

To investigate changes in plasma interleukin (IL)-6, cortisol or noradrenaline concentrations after surgery in elderly patients with postoperative confusion.

METHODS

We studied 80 patients aged 70-90 years undergoing abdominal surgery and measured plasma IL-6, cortisol or noradrenaline concentrations before surgery, at the end of surgery, and 24 and 48 h after surgery.

RESULTS

Plasma IL-6 concentrations in elderly patients with postoperative confusion were 83.2 +/- 30.5, 49.3 +/- 14.1 and 42.9 +/- 19.4 pg.ml(-1) at the end of surgery, and 24 and 48 h after surgery, respectively, being significantly higher than in elderly patients without postoperative confusion (58.0 +/- 37.5, 36.1 +/- 20.0 and 28.2 +/- 16.7 pg.ml(-1)). Plasma cortisol concentrations in elderly patients with postoperative confusion (42.2 +/- 7.8, 38.3 +/- 8.3 and 33.1 +/- 8.4 microg.dl(-1) at the end of surgery, and 24 and 48 h after surgery, respectively) were significantly higher than in elderly patients without postoperative confusion (32.9 +/- 6.7, 30.4 +/- 8.6 and 25.6 +/- 6.5 microg.dl(-1), respectively). There were no significant differences in plasma norepinephrine concentrations at all sampling points between elderly patients with and without postoperative confusion. However, plasma IL-6 and cortisol concentrations were related in elderly patients with postoperative confusion (at the end of surgery and 24 and 48 h after surgery). However, there was no relationship between plasma IL-6 and cortisol concentrations 24 and 48 h after surgery in elderly patients without postoperative confusion.

CONCLUSION

Elderly patients with postoperative confusion had increased plasma IL-6 and cortisol concentrations. The interaction between IL-6 and cortisol after surgery is associated with developing postoperative confusion in the elderly patients.

Dynamic change in plasma leptin level during the perioperative period

OBJECTIVE

To examine the association of plasma leptin level with insulin, which is known as a metabolic regulator of leptin, and various stress-related factors during the perioperative period.

METHODS

Thirty-one patients undergoing gastrectomy were enrolled and blood samples were obtained preoperatively, intraoperatively, immediately after operation, and on the first and second postoperative days.

RESULTS

The plasma leptin level showed a triphasic response. Immediately after operation, the leptin level was the lowest, while the serum cortisol and interleukin-6 (IL-6) levels had their peak (PHASE 1). On the first postoperative day, the leptin level had its peak with the serum cortisol and IL-6 level remaining elevated (PHASE 2). On the second postoperative day, while the serum cortisol and IL-6 levels still remained elevated, the plasma leptin level fell to the preoperative value (PHASE 3). The plasma leptin level correlated well with the insulin level at all time points during the study period.

CONCLUSION

Our results suggest a possible role of leptin in harmonizing neuroendocrine and immune responses with energy balance.

Schizophrenic patients who develop postoperative confusion have an increased norepinephrine and cortisol response to surgery

The purpose of this study was to investigate the relationship between postoperative confusion and the plasma norepinephrine (NE), adrenocorticotropin (ACTH) or cortisol response to surgery in schizophrenic patients. We studied 50 schizophrenic patients and 35 control patients who underwent orthopedic surgery and perioperatively measured plasma NE, ACTH and cortisol levels. Postoperative confusion during 72 h after the end of the operation occurred in 14 of 50 schizophrenic patients (28%) and in 2 of 35 control patients (6%). Plasma NE levels 15 min after skin incision, the next day, the second day and the third day after operation in schizophrenic patients with postoperative confusion (668.0 +/- 59.2, 522.0 +/- 96.5, 463.2 +/- 71.2 and 398.9 +/- 56.2 pg/ml, respectively) were significantly higher than those in schizophrenic patients without confusion (524.1 +/- 62.6, 342.4 +/- 38.6, 311.2 +/- 58.3 and 314.1 +/- 77.1 pg/ml, respectively). Plasma cortisol levels 15 min after the skin incision and the next and second days after operation in schizophrenic patients with postoperative confusion (23.6 +/- 3.2, 21.1 +/- 4.3 and 19.9 +/- 4.4 microg/dl, respectively) were significantly higher than those in schizophrenic patients without confusion (15.2 +/- 4.5, 14.3 +/- 5.1 and 13.8 +/- 3.8 microg/dl, respectively). In conclusion, the occurrence of postoperative confusion in schizophrenic patients is associated with an increase in plasma norepinephrine and cortisol levels during and after surgery.