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1.
Total hip replacement revision surgery is accompanied by significant blood loss. Using rotational thrombelastometry (ROTEM) perioperatively to diagnose coagulopathy may help to provide rapid aimed therapy and thus decrease blood loss and the consumption of transfusion products. The aim of this case-control study was to find out whether point of care using of ROTEM may reduce blood loss and the consumption of blood transfusion products in hip replacement revision surgery.Data were prospectively collected from patients who underwent hip replacement revision surgery in the period 2017 to 2018 when the management of bleeding and coagulopathy was based on the results of ROTEM. Data were compared with a group of historical controls for the period 2015 to 2016 when bleeding and coagulopathy management was not based on ROTEM results. The consumption of blood transfusion products and perioperative blood loss were compared between the groups.The total number of analyzed patients was 90. Forty five patients were analyzed in the ROTEM group and the same number of patients were analyzed in the non-ROTEM group. Significantly decreased perioperative consumption of fresh frozen plasma and packed red blood cells was found in the ROTEM, as well as decreased perioperative blood loss comparing to non-ROTEM group. All data were statistically different with P < .05.Perioperative management of bleeding and coagulopathy based on the results of ROTEM during hip replacement revision surgery seems to help to decrease perioperative blood loss and the consumption of blood transfusion products, especially fresh frozen plasma.  相似文献   
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Objective To evaluate the factors affecting optimal stent expansion in calcified lesions treated by aggressive plaque modification with rotational atherectomy (RA) and a cutting balloon (CB). Methods From January 2014 to May 2015, 92 patients with moderate to severe coronary calcified lesions underwent rotational atherectomy and intravascular ultrasound imaging at Chinese PLA General Hospital (Beijing, China) were included in this study. They were divided into a rotational artherectomy combined with cutting balloon (RACB) group (46 patients treated with RA followed by CB angioplasty) and an RA group (46 patients treated with RA followed by plain balloon angioplasty). Another 40 patients with similar severity of their calcified lesions treated with plain old balloon angioplasty (POBA) were demographically matched to the other groups and defined as the POBA group. All patients received a drug-eluting stent after plaque preparation. Lumen diameter and lumen diameter stenosis (LDS) were measured by quantitative coronary angiography at baseline, after RA, after dilatation, and after stenting. Optimal stent expansion was defined as the final LDS < 10%. Results The initial and post-RA LDS values were similar among the three groups. However, after dilatation, the LDS significantly decreased in the RACB group (from 54.5% ± 8.9% to 36.1% ± 7.1%) but only moderately decreased (from 55.7% ± 7.8% to 46.9% ± 9.4%) in the RA group (time × group, P< 0.001). After stenting, there was a higher rate of optimal stent expansion in the RACB group (71.7% in the RACB group, 54.5% in the RA group, and 15% in the POBA group, P < 0.001), and the final LDS was significantly diminished in the RACB group compared to the other two groups (6.0% ± 2.3%, 10.8% ± 3.3%, 12.7% ± 2.1%, P < 0.001). Moreover, an LDS ≤ 40% after plaque preparation (OR = 2.994, 95% CI: 1.297?6.911) was associated with optimal stent expansion, which also had a positive correlation with the appearance of a calcified ring split (r = 0.581, P < 0.001). Conclusions Aggressive plaque modification with RA and CB achieve more optimal stent expansion. An LDS ≤ 40% after plaque modification was a predictive factor for optimal stent expansion in calcified lesions. This parameter was also associated with the presence of calcified ring split.  相似文献   
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AIM: The purpose of this study was to evaluate the influence of rotational speed, torque, and operator experience with a specific Ni-Ti rotary instrumentation technique on the incidence of locking, deformation and separation of instruments. METHODOLOGY: ProFile Ni-Ti rotary instruments (PRI) sizes 40-15 with a 6% taper were used in a crown-down technique. In one group of canals (n = 300) speeds of 150, 250 and 350 rpm (subgroups 1, 2 and 3) were used. Each one of the subgroups included 100 canals. In a second group (n = 300) torque was set at 20, 30 and 55 Ncm (subgroups 4, 5 and 6). In the third group (n = 300) three operators with varying experience (subgroups 7, 8 and 9) were also compared. Each subgroup included the use of 10 sets of PRI and 100 canals of extracted human molars. Each set of PRI was used in up to 10 canals and then sterilized before each case. NaOCl 2.5% was used as an irrigant. The number of locked, deformed, and separated instruments for the different groups, and within each part of the study was analysed statistically for significance with chi-squared tests. RESULTS: In group 1 only one instrument was deformed in the 150-rpm group and no instruments separated or locked. In the 250-rpm group instrument separation did not occur, however, a high incidence of locking, deformation and separation was noted in the 350-rpm group. In general, instrument sizes 30-15 locked, deformed and separated. Chi-squared statistics showed a significant difference between the 150 and 350 rpm groups but no difference between the 150 and 250 rpm groups with regard to instrument separation. Overall, there was a trend toward a higher incidence of instrument deformation and separation in smaller instruments. Locking and separation occurred during the final passage of the instruments, in the last (tenth) canal in each subgroup. In the second group, neither separation nor deformation and locking occurred during the use of the ProFile instruments, at 150 rpm, and at the different torque values. In the third group, chi-squared analysis demonstrated that significantly more instruments separated with the least experienced operator. Instrument locking, deformation, and separation did not occur with the most experienced operator. CONCLUSIONS: Preclinical training in the use of the PRI technique with crown-down at 150 rpm were crucial in avoiding instrument separation and reducing the incidence of instrument locking and deformation.  相似文献   
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Purpose This in vitro study investigated the effect of lateral cyclic loading with different load positions and periods on abutment rotational displacement (RD) of external hexagon implant system. Materials and Methods Four groups of five implant assemblies each were used. Each assembly consisted of Brånemark System® Mk IV implant (Nobel Biocare AB, Göteborg, Sweden), CeraOne® abutment (Nobel Biocare AB), and a cement‐retained casting. A cyclic load of 50 N was applied centrally and perpendicular to the long axis of the implant for groups A and B for 0.25 and 0.50 × 106 cycles, respectively, while for groups C and D, the same load was applied at 4‐mm distance eccentrically for 0.25 and 0.50 × 106 cycles, respectively. The displacement was evaluated by hand drawing a longitudinal line across the implant‐abutment interface. Before and after loading, the lateral distance between two reference points on the abutment and implant was measured under high resolution (×200) and the difference formed the RD value. The data were analyzed with one‐way analysis of variance and compared with Tukey test (α=0.05). Results Group D had the highest mean of RD value (55.00 ± 1.871 μm), while group A had the lowest (2.800 ± 0.837 μm). Groups A and B had a high statistically significant difference in RD values, as compared to groups C or D (p < .001). Moreover, group C had statistically significant difference from group D (p=.011). Conversely, no statistical significance was obtained when group A was compared with group B. Conclusion Within the limits of this in vitro study, the RD of the external hexagon joint components occurred significantly under eccentric lateral loading when compared to centric loading. The displacement increased significantly with longer period of eccentric lateral loading.  相似文献   
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目的:探究系统性护理干预对乳腺微创旋切术患者心理状态及康复情况的影响。方法:将120例接受乳腺微创旋切术治疗的患者随机分为观察组(60例)和对照组(60例)。对照组采用常规护理干预,观察组采用系统性护理干预。比较两组患者术后疼痛、心理状态、并发症发生情况及对护理的满意度。结果:观察组护理满意度96.67%显著高于对照组的80.00%,观察组并发症发生率6.67%显著低于对照组的30.00%,差异有统计学意义(P<0.05)。观察组术后2h、6h、12h、24h的疼痛数字等级评定量表(Numerical rating scale,NRS)评分低于对照组,且观察组抑郁自评量表(Self-rating depression scale,SDS)评分、焦虑自评量表(Self-rating anxiety scale,SAS)评分均低于对照组,依从性评分显著高于对照组,差异有统计学意义(P<0.05)。结论:系统性护理干预在乳腺微创旋切术中应用效果良好,可有效降低并发症发生率,减轻患者疼痛及负性心理,提高其依从性及护理满意度,值得临床推广应用。  相似文献   
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ObjectivesThe aim of this study was to assess the safety and effectiveness of directional atherectomy (DA) for endovascular treatment of peripheral arterial disease (PAD) in infrainguinal arteries in patients with claudication or critical limb ischemia.BackgroundTo date, no prospective, multicenter, independently-adjudicated study has evaluated the effectiveness and durability of DA in the treatment of PAD. Previous DA studies have not been prospectively powered to evaluate any differences in outcomes in patients with and without diabetes.MethodsDEFINITIVE LE (Determination of EFfectiveness of the SilverHawk® PerIpheral Plaque ExcisioN System (SIlverHawk Device) for the Treatment of Infrainguinal VEssels / Lower Extremities) prospectively enrolled subjects at 47 multinational centers with an infrainguinal lesion length up to 20 cm. Primary endpoints were defined as primary patency at 12 months for claudicants and freedom from major unplanned amputation for critical limb ischemia (CLI) subjects. A pre-specified statistical hypothesis evaluated noninferiority of primary patency in diabetic versus nondiabetic claudicants. Independent angiographic and sonographic core laboratories assessed outcomes, and events were adjudicated by a clinical events committee.ResultsA total of 800 subjects were enrolled. The 12-month primary patency was 78% (95% confidence interval: 74.0% to 80.6%) in claudicants, with a 77% rate in the diabetic subgroup versus 78% in the nondiabetic subgroup (noninferior, p < 0.001). The rate of freedom from major unplanned amputation of the target limb at 12 months in CLI subjects was 95% (95% confidence interval: 90.7% to 97.4%). Periprocedural adverse events included embolization (3.8%), perforation (5.3%), and abrupt closure (2.0%). The bail-out stent rate was 3.2%.ConclusionsThe DEFINITIVE LE study demonstrated that DA is a safe and effective treatment modality at 12 months for a diverse patient population with either claudication or CLI. Furthermore, DA was shown to be noninferior for treating PAD in patients with diabetes compared with those without diabetes. (Study of SilverHawk/TurboHawk in Lower Extremity Vessels [DEFINITIVE LE]; NCT00883246).  相似文献   
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Introduction

The aim of this study was to evaluate the kinematics of 2 reciprocating motors and compare it with manufacturers' declared values.

Methods

VDW Silver (VDW, Munich, Germany) and ATR Tecnika (Tecnika, Pistoia, Italy) were used in the study in 5 working modes: continuous rotation at 400 rpm on VDW Silver and ATR Tecnika and reciprocating motion on ATR Tecnika at 400 rpm and on VDW Silver in Reciproc and WaveOne mode. The polishing disk with an optical target was inserted in the contra-angle and recorded with a 1000–frames per second video camera. The direction and the amount of rotation were analyzed by computer, and the following kinematics parameters were calculated: engaging and disengaging angles, cycle rotational speeds, engaging and disengaging rotational speeds, net cycle angle, total cycle angle, and number of cycles to complete full rotation. One-way analysis of variance followed by planned pair-wise comparisons was used to compare kinematics parameters. The alpha error was set to 0.05.

Results

Analysis of variance revealed a difference between actual and set values of all 3 reciprocating modes in all kinematics parameters (P < .001). No significant difference between the actual engaging angle of Reciproc and that of the WaveOne mode was found. For reciprocating motion on the ATR Tecnika at 400 rpm, the actual engaging and disengaging angles were 8- and 9-fold greater, respectively, compared with set angles (P < .001).

Conclusions

The kinematics of reciprocating instrumentation is more complex than it seems as described only with angles and rotational speed. Actual kinematics values differ from manufacturers' declared values.  相似文献   
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