Context Pretreatment with α-adrenergic receptor blockers is recommended to prevent hemodynamic instability during resection of a pheochromocytoma or sympathetic paraganglioma (PPGL). Objective To determine which type of α-adrenergic receptor blocker provides the best efficacy. Design Randomized controlled open-label trial (PRESCRIPT; ClinicalTrials.gov NCT01379898) Setting Multicenter study including 9 centers in The Netherlands. Patients 134 patients with nonmetastatic PPGL. Intervention Phenoxybenzamine or doxazosin starting 2 to 3 weeks before surgery using a blood pressure targeted titration schedule. Intraoperative hemodynamic management was standardized. Main Outcome Measures Primary efficacy endpoint was the cumulative intraoperative time outside the blood pressure target range (ie, SBP >160 mmHg or MAP <60 mmHg) expressed as a percentage of total surgical procedure time. Secondary efficacy endpoint was the value on a hemodynamic instability score. Results Median cumulative time outside blood pressure targets was 11.1% (interquartile range [IQR]: 4.3–20.6] in the phenoxybenzamine group compared to 12.2% (5.3–20.2)] in the doxazosin group (P = .75, r = 0.03). The hemodynamic instability score was 38.0 (28.8–58.0) and 50.0 (35.3–63.8) in the phenoxybenzamine and doxazosin group, respectively (P = .02, r = 0.20). The 30-day cardiovascular complication rate was 8.8% and 6.9% in the phenoxybenzamine and doxazosin group, respectively (P = .68). There was no mortality after 30 days. Conclusions The duration of blood pressure outside the target range during resection of a PPGL was not different after preoperative treatment with either phenoxybenzamine or doxazosin. Phenoxybenzamine was more effective in preventing intraoperative hemodynamic instability, but it could not be established whether this was associated with a better clinical outcome.

Objective: Hypopituitarism after traumatic brain injury (TBI) is considered to be a prevalent condition. However, prevalence rates differ considerably among reported studies, due to differences in definitions, endocrine assessments of hypopituitarism, and confounding factors, such as timing of evaluation and the severity of the trauma. Aim: To evaluate the prevalence of hypopituitarism in a large cohort of TBI patients after long-term follow-up using a standardized endocrine evaluation. Study design: Cross-sectional study. Patients and methods:We included 112 patients with TBI, hospitalized for at least 3 days and duration of follow-up O1 year after TBI from five (neurosurgical) referral centers. Evaluation of pituitary function included fasting morning hormone measurements and insulin tolerance test (nZ90) or, when contraindicated, ACTH stimulation and/or CRH stimulation tests and a GH releasing hormonearginine test (nZ22). Clinical evaluation included quality of life questionnaires. Results: We studied 112 patients (75 males), with median age 48 years and mean body mass index (BMI) 26.7G4.8 kg/m 2 . Mean duration of hospitalization was 11 (3-105), and 33% of the patients had a severe trauma (Glasgow Coma Scale !9) after TBI. The mean duration of follow-up was 4 (1-12) years. Hypopituitarism was diagnosed in 5.4% (6/112) of patients: severe GH deficiency (nZ3), hypogonadism (nZ1), adrenal insufficiency (nZ2). Patients diagnosed with pituitary insufficiency had significantly higher BMI (PZ0.002). Conclusion: In this study, the prevalence of hypopituitarism during long-term follow-up after TBI was low. Prospective studies are urgently needed to find reliable predictive tools for the identification of patients with a significant pre-test likelihood for hypopituitarism after TBI.

GH secretion is regulated by the interaction of GHRH and somatostatin and is released in 10-20 pulses in each 24-h cycle. The exact roles in pulse generation played by somatostatin, GHRH, and the recently isolated GH-releasing peptide, Ghrelin, are not fully elucidated. To investigate the GHRH-mediated GH secretion in human, we investigated pulsatile, entropic, and 24-h rhythmic GH secretion in two young adults (male, 24 yr; female, 23 yr) from a Moroccan family with a novel inactivating defect of the GHRH receptor gene. Data were compared with values in age- and gender-matched controls. Plasma GH concentration were measured by a sensitive immunofluorometric assay, with a detection limit of 0.01 mU/L. All plasma GH concentrations in the female patient were measurable; in the male patient 30 of 145 samples were at or below the detection limit. GH secretion was pulsatile, with 21 and 23 secretory episodes/24 h in the male and female patients, respectively. The fraction of basal to total GH secretion was raised in both patients by 0.18 and 0.15, respectively. The total 24-h GH production rate was greatly diminished; in the male patient it was 6.9 mU/L (normal values for his age, 26--63 mU/L), and in the female patient it was 4.2 mU/L (normal values for her age, 96--390 mU/L). The nyctohemeral plasma GH rhythm was preserved (P < 0.001), with normal acrophases (0430 and 0218 h in the male and female, respectively). Approximate entropy was greatly elevated in both subjects (0.82 in the male and 1.17 in the female; upper normal values for age and gender, 0.24 and 0.59, respectively). Intravenous injection of 50 microg GHRH failed to increase the plasma GH concentration in both patients, but 100 microg GH-releasing peptide-2 elicited a definite increase (male patient, 0.13 to 1.74 mU/L; female patient, 0.29 to 0.87 mU/L). Both patients had a partial empty sella on magnetic resonance imaging scanning. In summary, the present studies in two patients with a profound loss of function mutation of the GHRH receptor favor the view that in the human the timing of GH pulses is primarily supervised by intermittent somatostatin withdrawal, and the amplitude of GH pulses is driven by GHRH. In addition, we infer that effectual GHRH input controls the GH cell mass and the orderliness of the secretory process.

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OBJECTIVE To investigate whether the spontaneous secretion of growth hormone and prolactin in adult patients with pituitary‐dependent Cushing's disease is decreased. PATIENTS Fourteen adult patients (9 women, 5 men; age: 34 ± 3.4 years, mean ± SEM) with pituitary‐dependent Cushing's disease and 14 controls matched for age, gender and body mass index were studied. METHODS Blood samples were withdrawn at 10 minutes intervals starting at 0900 h for 24 h. GH and PRL release were quantified with deconvolution methods. The regularity of GH and PRL release was measured with approximate entropy statistics. RESULTS The number of GH secretory events per 24 h was higher in patients than in controls: 19 ± 1.3 vs. 14 ± 1.5 peaks per 24 h, respectively (P = 0.020). GH secretion rate was about one quarter lower in patients (ns), and the 24 h secretion of PRL was unchanged. Total GH production correlated negatively with the urinary excretion of free cortisol (R = 0.729, P = 0.005) and with the plasma cortisol production rate (R = 0.613; P = 0.026). The orderliness of GH and PRL secretion was appraised with the approximate entropy statistic (ApEn). For GH secretion ApEn(1,20%) in patients was 0.952 ± 0.084 vs. 0.404 ± 0.047 in controls, P = 1.17 × 10−4, pointing to a markedly disordered secretion in patients. Similar results were obtained for PRL secretion: patients: 1.586 ± 0.063 vs. 1.003 ± 0.068 in controls, P = 3.67 × 10−5. No statistically significant differences in secretory dynamics were demonstrated between the 10 patients with a microadenoma and the four with a macroadenoma. CONCLUSION The amount of GH released spontaneously into the circulation in adult patients with pituitary‐dependent Cushing's disease is inversely related to the degree of cortisol hypersecretion. However, except for severe hypercortisolism, GH secretion is relatively preserved. In addition, secretion of GH and PRL is remarkably disordered in patients with Cushing's disease. Since we could not detect differences in GH and/or PRL secretory dynamics between patients with a microadenoma and those harboring a macroadenoma, we speculate that an intrapituitary paracrine mechanism and/or elevated cortisol feedback effects may be responsible for the evident disruption of GH and PRL secretion patterns.