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1.
The effectiveness of prophylactic desmopressin acetate in reducing hemorrhage after cardiopulmonary bypass operations is controversial. We conducted a prospective, randomized, placebo-controlled, double-blind trial to determine its effectiveness and safety in such patients. Eighty-three evaluable patients undergoing valvular heart operations were randomized to receive desmopressin (0.3 microgram/kg) (41) or placebo (42) after cardiac bypass. Demographic characteristics were similar in both groups. There was no significant difference in total 24-hour blood loss between groups (desmopressin 1064.8 +/- 647.1 ml versus placebo 844.4 +/- 507.6 ml; p greater than 0.05), or in the requirement for red blood cell, platelet, or fresh frozen plasma transfusion, or for reexploration for control of hemorrhage. Neither was there a difference in the occurrence of thrombotic complications between groups. Analysis of factor VIII activity, von Willebrand factor, or von Willebrand factor multimers failed to show significant correlations with blood loss or differences between groups except for factor VIII activity, which was significantly higher in the desmopressin group 1 hour after operation than in the placebo group. A detailed comparative analysis of similar trials to determine the reasons for different outcomes suggests that desmopressin should not be used routinely as a prophylactic agent to reduce postsurgical hemorrhage, but that it may be beneficial when used in patients who already manifest excessive bleeding postoperatively.  相似文献   
2.
The influence of trauma and hemorrhagic shock on the non-specific immune system has been pointed out in various experimental studies. Other investigations have also been able to find a relationship between these changes and a higher incidence of post-traumatic complications in the form of organ failure. Our aim was to demonstrate the potential changes in the cellular defense system in a clinical study on multiple trauma patients. The polymorphonuclear leukocytes (PMNL) are the main representative of the mobile, non-specific immune system. Our study revealed a significant deterioration of PMNL function after trauma. The metabolic activity and phagocytic function were mainly affected by a decrease in the concentration of so-called "opsonins." The opsonins are important for the identification and engulfment of debris (necrosis, fat emboli and thrombi) and bacterial substances (endotoxin). Next to the opsonin level, a change in the receptor configuration is important for phagocytosis. However, we could not find any substantial evidence of surface receptor alteration. The reticuloendothelial cells (RES), a stationary phagocytic system, also showed a significant reduction in clearance function in these polytraumatized patients. Similar to PMNL, these disturbances were based on the reduction of the opsonine concentration. We were able to demonstrate a significant disturbance in immune function in multiple trauma patients with post-traumatic complications compared to patients with a normal clinical course after injury. Disturbances in the PMNL function (seen after 4 days) were found to appear after the RES disturbances. Systemic interaction between these two phagocytic systems cannot be excluded and further investigation is therefore required.  相似文献   
3.
OBJECTIVE: Disadvantages associated with commercially available vascular implants necessitate alternative strategies to develop new vascular prostheses. Although many tissue characterizing strategies have been defined, no valid test for thrombogenicity exists. Here we introduce a novel concept for thrombogenicity testing of vascular implants METHODS: Silastic tubes were implanted into the carotid arteries of 12 sheep. After placing these shunts, tc99m-labeled platelets were administered and test-vessels were put in between the shunts. Native autologous (n=6), as well as native/acellularized allogeneic (n=6/n=6), and xenogeneic (n=6/n=6) carotid arteries and allogeneic (n=6/n=6) and xenogeneic (n=6/n=6) carotid arteries reseeded with allogeneic endothelial-cells, fibroblasts and myocytes were evaluated. Number and time course of intra-operatively deposited platelets were evaluated with a Geiger-counter; certain areas of platelet deposition located, envisioned and characterized by a gamma-camera and scanning electron-microscopy afterwards. RESULTS: Counter results revealed no significant different platelet depositions when comparing silastic tubes with either autologous or allogeneic native carotid arteries. However, starting 5 minutes after placement, acellularized/reseeded allogeneic (p=0.001/p=0.00004), and xenogeneic (p=0.0001/p=0.01) carotid arteries showed significantly more platelet depositions than native autologous carotides. Moreover, it was possible to show that almost no platelets adhere to native vessels or silastic tubes, thus proving the test method itself. CONCLUSION: The Ex-Vivo-Shunt-Model is a valid method to measure and envision the intrinsic thrombogenicity of vascular implants.  相似文献   
4.
Glomus vagale are rare vascular tumours of the paraganglion cells of the vagus nerve, and they usually occur in the carotid space. Tumours can be familial, multicentric, malignant but rarely hormonally active. A rare case is reported of glomus vagale presenting as a supraclavicular mass.  相似文献   
5.
The concept of haemostatic resuscitation implies early and high‐volume plasma transfusion. We investigated the haemostatic profile of reconstituted whole blood prepared in a 1:1:1 ratio of blood, platelets and plasma. This consisted of packed red blood cells, platelet concentrate and four different plasma variants: fresh frozen; solvent‐detergent; lyophilised quarantine; and lyophilised methylene blue‐inactivated plasma. Haematocrit, platelet count, endogenous thrombin potential and coagulation factor activity were significantly lower in reconstituted blood compared with citrated whole blood (p < 0.01). Except for lyophilised methylene blue‐inactivated plasma, no substantial differences between plasma variants in coagulation factor activity, endogenous thrombin potential and standard coagulation tests were observed. After reconstitution, haematocrit and platelet counts were slightly above recommended transfusion triggers, most thromboelastometry (ROTEM®) parameters were within the normal range and fibrinogen concentrations were between 1.57 g.l?1 and 1.91 g.l?1. Reconstitution of whole blood in a 1:1:1 ratio resulted in significant dilution of haematocrit and platelet count, but values remained above limits recommended by transfusion guidelines. Fibrinogen concentrations of reconstituted whole blood were also significantly reduced, and these were below the threshold value for supplementation recommended by recent guidelines.  相似文献   
6.
Conjoint bicondylar Hoffa fracture is an extremely rare injury. Only one case has been reported previously in the pediatric age group. We describe this injury in a 17-year-old male who presented following a fall with direct impact on his semiflexed right knee. Plain radiographs were inadequate to define the exact pattern of injury. Computed tomographic (CT) scans demonstrated the coronal fracture involving both the femoral condyles which were joined by a bridge of intact bone. The patient was treated with open reduction and internal fixation using swashbuckler (modified anterior) approach. Union occurred within 3 months and at final followup (at 18 months) the patient had a good clinical outcome. The possible mechanism of injury is discussed.  相似文献   
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Clinically useful definitions of emotion regulation with respect to deliberate self-harm (referred to here as self-injury) focus on adaptive ways of responding to emotional distress rather than on the control of emotions or dampening of emotional arousal. According to one such definition, emotion regulation is a multifaceted construct involving a) the awareness, understanding, and acceptance of emotions; b) ability to engage in goal-directed behaviors, and inhibit impulsive behaviors, when experiencing negative emotions; c) the flexible use of situationally appropriate strategies to modulate the intensity and/or duration of emotional responses rather than to eliminate emotions entirely; and d) willingness to experience negative emotions as part of pursuing meaningful activities in life (Gratz & Roemer, 2004). This article addresses the role of emotion dysregulation in self-injury and discusses two treatments for self-injury that explicitly focus on increasing emotion regulation. These treatments are based on the premise that the reduction of emotion dysregulation will decrease the need for maladaptive behaviors that function to regulate emotions, such as self-injury. A case illustration describing how one of these treatments (an acceptance-based, emotion regulation group therapy) is used to treat self-injury is provided.  相似文献   
10.
Extracorporeal membrane oxygenation (ECMO) is gaining importance in the perioperative management of lung transplant patients. To date, the ideal substance for anticoagulation of ECMO patients is still a matter of debate. In this study, we describe our experience with the use of low molecular weight heparin (LMWH) in comparison with unfractioned heparin (UFH) in lung transplant patients undergoing perioperative ECMO support. We retrospectively analyzed data from all lung transplant patients who underwent perioperative ECMO support at our institution between 2013 and 2017. Bleeding events served as primary outcome parameter. Secondary outcome parameters consisted of thromboembolic events. 102 patients were included in this study, of which 22 (21.6%) received UFH for anticoagulation, and 80 (78.4%) received LMWH. There was no difference between the two groups in regard to serious bleeding events (22.7% in the UFH group vs 12.5% in the LMWH group, P = .31). However, the proportion of patients experiencing thromboembolic events was significantly higher in the UFH group than in the LMWH group (50% vs 20%, P = .01). After adjusting for baseline differences between the two groups, we still observed a difference with respect to thromboembolic events. These data remain to be validated in future prospective, randomized trials.  相似文献   
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