In vitro norepinephrine significantly activates isolated platelets from healthy volunteers and critically ill patients following severe traumatic brain injury

INTRODUCTION: Norepinephrine, regularly used to increase systemic arterial blood pressure and thus improve cerebral perfusion following severe traumatic brain injury (TBI), may activate platelets. This, in turn, could promote microthrombosis formation and induce additional brain damage. METHODS: The objective of this study was to investigate the influence of norepinephrine on platelets isolated from healthy volunteers and TBI patients during the first two post-traumatic weeks. A total of 18 female and 18 male healthy volunteers of different age groups were recruited, while 11 critically ill TBI patients admitted consecutively to our intensive care unit were studied. Arterial and jugular venous platelets were isolated from norepinephrine-receiving TBI patients; peripheral venous platelets were studied in healthy volunteers. Concentration-dependent functional alterations of isolated platelets were analyzed by flow cytometry, assessing changes in surface P-selectin expression and platelet-derived microparticles before and after in vitro stimulation with norepinephrine ranging from 10 nM to 100 microM. The thrombin receptor-activating peptide (TRAP) served as a positive control. RESULTS: During the first week following TBI, norepinephrine-mediated stimulation of isolated platelets was significantly reduced compared with volunteers (control). In the second week, the number of P-selectin- and microparticle-positive platelets was significantly decreased by 60% compared with the first week and compared with volunteers. This, however, was associated with a significantly increased susceptibility to norepinephrine-mediated stimulation, exceeding changes observed in volunteers and TBI patients during the first week. This pronounced norepinephrine-induced responsiveness coincided with increased arterio-jugular venous difference in platelets, reflecting intracerebral adherence and signs of cerebral deterioration reflected by elevated intracranial pressure and reduced jugular venous oxygen saturation. CONCLUSION: Clinically infused norepinephrine might influence platelets, possibly promoting microthrombosis formation. In vitro stimulation revealed a concentration- and time-dependent differential level of norepinephrine-mediated platelet activation, possibly reflecting changes in receptor expression and function. Whether norepinephrine should be avoided in the second post-traumatic week and whether norepinephrine-stimulated platelets might induce additional brain damage warrant further investigations

Interobserver reliability of classification and characterization of proximal humeral fractures: a comparison of two and three-dimensional CT

Interobserver reliability for the classification of proximal humeral fractures is limited. The aim of this study was to test the null hypothesis that interobserver reliability of the AO classification of proximal humeral fractures, the preferred treatment, and fracture characteristics is the same for two-dimensional (2-D) and three-dimensional (3-D) computed tomography (CT). Members of the Science of Variation Group--fully trained practicing orthopaedic and trauma surgeons from around the world--were randomized to evaluate radiographs and either 2-D CT or 3-D CT images of fifteen proximal humeral fractures via a web-based survey and respond to the following four questions: (1) Is the greater tuberosity displaced? (2) Is the humeral head split? (3) Is the arterial supply compromised? (4) Is the glenohumeral joint dislocated? They also classified the fracture according to the AO system and indicated their preferred treatment of the fracture (operative or nonoperative). Agreement among observers was assessed with use of the multirater kappa (κ) measure. Interobserver reliability of the AO classification, fracture characteristics, and preferred treatment generally ranged from "slight" to "fair." A few small but statistically significant differences were found. Observers randomized to the 2-D CT group had slightly but significantly better agreement on displacement of the greater tuberosity (κ = 0.35 compared with 0.30, p < 0.001) and on the AO classification (κ = 0.18 compared with 0.17, p = 0.018). A subgroup analysis of the AO classification results revealed that shoulder and elbow surgeons, orthopaedic trauma surgeons, and surgeons in the United States had slightly greater reliability on 2-D CT, whereas surgeons in practice for ten years or less and surgeons from other subspecialties had slightly greater reliability on 3-D CT. Proximal humeral fracture classifications may be helpful conceptually, but they have poor interobserver reliability even when 3-D rather than 2-D CT is utilized. This may contribute to the similarly poor interobserver reliability that was observed for selection of the treatment for proximal humeral fractures. The lack of a reliable classification confounds efforts to compare the outcomes of treatment methods among different clinical trials and reports

Management of traumatic brain injury

In the past years several recommendations have been published concerning the diagnostic work-up and treatment of patients with traumatic brain injury (TBI). They show that with regard to the surgical management of acute epidural hematomas, acute subdural hematomas, traumatic parenchymal lesions, posterior fossa mass lesions, as well as depressed skull fractures there is a lack of controlled studies, which would allow to define standards of treatment or guidelines, respectively. Nonetheless, treatment protocols serve an important purpose, because they may improve management of TBI patients by promoting uniform decision-making in the treatment of these patients, namely in • the identification of the few patients likely to suffer from complications among the large number of patients who sustain a mild to moderate head injury and • strategies for avoiding posttraumatic cerebral ischemia. In this context, the authors focus on the importance of plain skull X-rays and CT scan, respectively, in the work-up of mild TBI patients and on the indications for decompressive craniectomy for the relief of intractable elevation of intracranial pressure following severe TB

C-clamp and pelvic packing for control of hemorrhage in patients with pelvic ring disruption

BACKGROUND: Exsanguinating hemorrhage is the major cause of death in patients with pelvic ring disruption. AIMS: The aim of this study was to document outcomes after the stabilization of pelvic ring injuries by a C-clamp and control of hemorrhage by pelvic packing. Physiological parameters were tested as prognostic factors. SETTING AND DESIGN: This was a retrospective study at a level I trauma center. The study period was from January 1996 to December 2007. MATERIALS AND METHODS: Fifty patients with pelvic ring disruption and hemorrhagic shock were analyzed. The pelvic rings were fixed by a C-clamp, and patients with ongoing hemorrhage underwent laparotomy and extra- and/or intra-peritoneal pelvic packing. Clinical parameters (heart rate, mean arterial pressure) and physiological parameters (lactate levels, hemoglobin, hematocrit) were documented at admission and at different time points during the initial treatment (1, 2, 3, 4, 6, 8, and 12h after admission). RESULTS: Within 12 h of admission, 16 patients died (nonsurvivors) due to hemorrhagic shock (n=13) or head injuries (n=3). In this group, 12 patients underwent laparotomy with pelvic packing. Thirty-four patients survived the first 12 h (early survivors) after fixation by a C-clamp and additional packing in 23 patients. Four of these patients died 12.3±7.1 days later due to multiple organ failure (n=3) or severe head injury (n=1). The blood lactate level at admission was significantly higher in the group of nonsurvivors (7.2±0.8 mmol/L) compared to the early survivors (4.3±0.5 mmol/L, P<0.05). While hemoglobin values improved within the first 2 h in nonsurvivors, lactate levels continued to increase. CONCLUSION: Pelvic packing in addition to the C-clamp fixation effectively controls severe hemorrhage in patients with pelvic ring disruption. Early sequential measurements of blood lactate levels can be used to estimate the severity of shock and the response to the shock treatment

Low T3 Syndrome in Head-Injured Patients is Associated with Prolonged Suppression of Markers of Cell-Mediated Immune Response

Purpose:: To clarify the association between disturbed thyroid hormone metabolism (low T3 syndrome) and release of cytokines and markers of cell-mediated immune response. Material and Methods:: Concentrations of cytokines as well as of thyroid hormones were determined in 32 patients suffering from severe traumatic brain injury: interleukin-( IL-)1, IL-6, IL-10, tumor necrosis factor, transforming growth factor-(TGF-)β, soluble interleukin-2 receptor (sIL-2R), neopterin, and β2-microglobulin (β2m) in serum and cerebrospinal fluid; triiodothyronine (T3), free T3, thyroxine (T4), free T4, thyrotropin, thyroxine-binding globulin, and albumin in serum. Additionally, clinical parameters were assessed: Glasgow Coma Score, CT scan, intracranial pressure, Glasgow Outcome Score, and occurrence of pneumonia. Results:: Among 31 patients with a low T3 syndrome, those with additional low serum T4 levels (n = 13) showed a prolonged suppression of serum β2m, neopterin, and sIL-2R, and a higher secondary increase of serum β2m, neopterin, and TGF-β, as well as lower T3 levels (all p < 0.05). These patients also had a longer stay in the intensive care unit (34 ± 6 days vs. 22 ± 12 days; p = 0.008). Increased levels of β2m correlated with a preceding decrease of thyrotropin (cerebrospinal fluid: r = -0.53; p = 0.004; serum: r = -0.41; p = 0.029). Associations of thyroid hormone metabolism with either other cytokines or with clinical parameters were not detected. Conclusion:: These results show that low T3 syndrome is a very common pathophysiological feature after severe traumatic brain injury. The association of a low T3 syndrome in combination with low serum T4 levels, with an altered time course of markers of cell-mediated immunity led the authors to hypothesize that a disturbed thyroid hormone metabolism may be interrelated with a prolonged cellular immune dysfunction after traumatic brain injur

Synchronous bilateral ductal carcinoma in situ of the male breast associated with gynecomastia in a 30-year-old patient following repeated injections of stanozolol

We report a rare case of synchronous bilateral and multifocal ductal carcinoma in situ (DCIS) in a 30-year-old patient operated on for gynecomastia following repeated injections of stanozolol, a non-aromatizable androgen. The familial medical history was negative for breast cancer and work-up of serum hormone levels was normal. The patient underwent a modified radical mastectomy without axilla dissection 6 weeks following the primary procedure and recovered uneventfully. The role of synthetic androgens in the development of male breast neoplasia warrants further scrutiny

Intussusception as a cause of bowel obstruction in adults

Due to its unspecific presentation, intussusception is often diagnosed with delay in adults