Intense endurance exercise causes acute dysfunction of the RV, but not the LV. Although short-term recovery appears complete, chronic structural changes and reduced RV function are evident in some of the most practiced athletes, the long-term clinical significance of which warrants further study.

Exercise induces a relative increase in RVES-σ which exceeds LVES-σ. In athletes, greater RV enlargement and greater wall thickening may be a product of this disproportionate load excess.

Our study demonstrated elevations in total plasma cortisol and CBG concentrations during pregnancy and with low-dose OCP use. Pregnancy was also associated with significant increases in plasma free cortisol and UFC, suggesting that the rise in total plasma cortisol is contributed to by up-regulation of the maternal hypothalamic-pituitary-adrenal axis in addition to elevated CBG.

Pulmonary transit of agitated contrast (PTAC) occurs to variable extents during exercise. We tested the hypothesis that the onset of PTAC signifies flow through larger-caliber vessels, resulting in improved pulmonary vascular reserve during exercise. Forty athletes and fifteen nonathletes performed maximal exercise with continuous echocardiographic Doppler measures [cardiac output (CO), pulmonary artery systolic pressure (PASP), and myocardial velocities] and invasive blood pressure (BP). Arterial gases and B-type natriuretic peptide (BNP) were measured at baseline and peak exercise. Pulmonary vascular resistance (PVR) was determined as the regression of PASP/CO and was compared according to athletic and PTAC status. At peak exercise, athletes had greater CO (16.0 ± 2.9 vs. 12.4 ± 3.2 l/min, P < 0.001) and higher PASP (60.8 ± 12.6 vs. 47.0 ± 6.5 mmHg, P < 0.001), but PVR was similar to nonathletes (P = 0.71). High PTAC (defined by contrast filling of the left ventricle) occurred in a similar proportion of athletes and nonathletes (18/40 vs. 10/15, P = 0.35) and was associated with higher peak-exercise CO (16.1 ± 3.4 vs. 13.9 ± 2.9 l/min, P = 0.010), lower PASP (52.3 ± 9.8 vs. 62.6 ± 13.7 mmHg, P = 0.003), and 37% lower PVR (P < 0.0001) relative to low PTAC. Right ventricular (RV) myocardial velocities increased more and BNP increased less in high vs. low PTAC subjects. On multivariate analysis, maximal oxygen consumption (VO(2max)) (P = 0.009) and maximal exercise output (P = 0.049) were greater in high PTAC subjects. An exercise-induced decrease in arterial oxygen saturation (98.0 ± 0.4 vs. 96.7 ± 1.4%, P < 0.0001) was not influenced by PTAC status (P = 0.96). Increased PTAC during exercise is a marker of pulmonary vascular reserve reflected by greater flow, reduced PVR, and enhanced RV function.

No abstract

Patients undergoing surgical resection of pituitary adenomas are frequently given perioperative glucocorticoid therapy. There are no randomized controlled studies assessing the need for such steroids; however, several studies have documented changes in the hypothalamic-pituitary-adrenal (HPA) axis associated with pituitary surgery. Based on the evidence available, this article details recommendations for the perioperative management of glucocorticoid therapy in patients with pituitary tumors. For patients with proven ACTH deficiency preoperatively [usually based on response to a short ACTH 1-24 (Synacthen) test], 48 hours of supraphysiological glucocorticoid therapy should be administered perioperatively (e.g. hydrocortisone, 50 mg every 8 hours on day 0, 25 mg every 8 hours on day 1, and 25 mg at 0800 h on day 2). For patients with intact HPA function preoperatively, and in whom selective adenomectomy is possible, perioperative glucocorticoids are not necessary. Early postoperative assessment depends on daily clinical assessment of the patient and 0800 h plasma cortisol levels. Cortisol levels over 450 nM (16 microg/dl) reflect normal HPA function, and levels less than 100 nM (3.6 microg/dl) are consistent with ACTH deficiency. Cortisol levels between 100 and 250 nM (3.6-9 microg/dl) may be ACTH deficient and should receive morning hydrocortisone replacement until definitive HPA axis testing. Cortisol levels between 250 and 450 nM (9-16 microg/dl) are unlikely to be ACTH deficient but should receive additional steroids for stress until a definitive test is performed. For those requiring definitive testing, the insulin tolerance test, the overnight metyrapone test, or the glucagon stimulation test are appropriate and may be performed as early as d 7-10 or, if more convenient, wk 4-6. Following the guidelines suggested here should reduce the use of unnecessary glucocorticoids, while ensuring the safety of patients is not compromised.

Telephone coaching improved glycaemic control and adherence to complication screening in people with type 2 diabetes, for the duration of its delivery, but these effects were not maintained on withdrawal of the intervention. Strategies that assist patients to sustain these benefits are required.

Summary The utility of measuring salivary cortisol has become increasingly appreciated since the early 1980s. Salivary cortisol is a measure of active free cortisol and follows the diurnal rhythm of serum or plasma cortisol. The saliva sample may be collected by drooling or through the use of absorbent swabs which are placed into the mouth until saturated. Salivary cortisol is therefore convenient for patients and research participants to collect noninvasively on an outpatient basis. Several assay techniques have been used to measure salivary cortisol, including radioimmunoassay and more recently liquid chromatography–tandem mass spectrometry. The analytical sensitivity varies between these assay methods, as does the potential for cross‐reactivity with other steroids. The interpretation of salivary cortisol levels relies on rigorous standardization of sampling equipment, sampling protocols and assay technology with establishment of a local reference range. Clinically, the commonest use for salivary cortisol is measuring late‐night salivary cortisol as a screening test for Cushing's syndrome. Several studies have shown diagnostic sensitivities and specificities of over 90%, which compares very favourably with other screening tests for Cushing's syndrome such as the 24‐h urinary‐free cortisol and the 1‐mg overnight dexamethasone suppression test. There are emerging roles for the use of salivary cortisol in diagnosing adrenal insufficiency, particularly in conditions associated with low cortisol–binding globulin levels, and in the monitoring of glucocorticoid replacement. Finally, salivary cortisol has been used extensively as a biomarker of stress in a research setting, especially in studies examining psychological stress with repeated measurements.