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51.
Background ContextOblique lateral interbody fusion (OLIF)–has become a widely used, efficient surgical tool for various degenerative lumbar conditions. Postoperative ileus (POI) is a relatively common complication after anterior lumbar interbody fusion due to the manipulation of the intestine during the surgical approach. However, to our knowledge, little is known about POI following OLIF even though it also involves bowel manipulation during a surgical procedure.PurposeTo assess the incidence of POI and identify independent risk factors for POI development after OLIF.Study Design/SettingRetrospective cohort study.Patient SampleAll consecutive patients who underwent OLIF and percutaneous pedicle screw instrumentation from August 2012 until October 2019 at a single institutionOutcome MeasuresPatient demographics (sex, age, body weight, height, and body mass index), comorbidities (diabetes mellitus, gastroesophageal reflux disease, antithrombotic medication, previous abdominal surgery, and previous lumbar surgery), and perioperative details (preoperative diagnosis, number of levels fused, inadvertent endplate fracture during cage insertion, type of interbody graft, intraoperative estimated blood loss, duration of surgery and anesthesia, the amount of intraoperative remifentanil and propofol used as anesthetic agents, the total postoperative retroperitoneal closed-suction drainage output, and the cumulative opioid dosage administered in the first 72 hours postoperatively).MethodsPOI was defined as 2 or more of the following at 72 hours postoperatively: (1) ongoing nausea or vomiting postoperatively, (2) the absence of flatus over last 24-hour period, (3) inability to tolerate an oral diet over last 24-hour period, (4) ongoing abdominal distention postoperatively, and (5) radiological confirmation. The subjects were divided into 2 groups: patients with POI and those without POI. Binary logistic regression analyses were performed on demographics, comorbidities, and perioperative factors to identify independent risk factors for POI.ResultsEighteen (3.9%) of 460 patients experienced POI after OLIF and percutaneous pedicle screw instrumentation. Patients with POI had a significantly longer postoperative length of hospital stay than those without POI (8.61 ± 2.66 vs 6.48 ± 2.64, p = .001). Multivariate logistic regression analysis identified inadvertent endplate fracture (adjusted odds ratio = 6.017, p = .001) and the amount of intraoperative remifentanil (adjusted odds ratio = 1.057, p = .024) as independent risk factors for the occurrence of POI following OLIF.ConclusionThis study identified inadvertent endplate fracture and the amount of intraoperative remifentanil as independent risk factors for the development of POI after OLIF.  相似文献   
52.
BACKGROUND CONTEXTSurgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death.PURPOSETo develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors.STUDY DESIGN/SETTINGRetrospective, single-center study.PATIENT SAMPLEConsecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer centerOUTCOME MEASURESIOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused.METHODSWe identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression.RESULTSMean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (β=25.43 per point; p<0.001), and preoperative albumin (β=?244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/).CONCLUSIONSHere we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion.  相似文献   
53.
54.
BACKGROUND CONTEXTSurgical correction strategies for adult spinal deformity (ASD) relies heavily on radiographic alignment goals, however, there is often debate regarding degree of correction and how static alignment translates to physical ability in daily life. Kinematic analysis has the potential to improve the concept of ideal spinal alignment by providing clinically meaningful estimates of dynamic changes in spinal alignment during activities of daily life.PURPOSEEstimate representative dynamic ranges of spinal alignment during gait among ASD patients using 3D motion tracking; compare dynamic alignment between mild and severe deformity patients and to healthy adults.STUDY DESIGN/SETTINGRetrospective review at a single institution.PATIENT SAMPLEFifty-two ASD patients and 46 healthy adults.OUTCOME MEASURESRadiographic alignment, kinematic spine motion, spatiotemporal gait measures, patient reported outcomes (VAS pain, ODI, SRS-22r).METHODSSpinal alignment was assessed radiographically and during standing and overground walking tests. Dynamic alignment was initialized by linking radiographic alignment to kinematic alignment during standing and at initial heel contact during gait. Dynamic changes in maximums and minimums during gait were made relative to initial heel contact for each gait cycle. Total range-of-motion (RoM) was measured for both ASD and healthy subjects. Dynamic alignment measures included coronal and sagittal vertical axes (CVA, SVA), T1 pelvic angle (TPA), lumbar lordosis (LL), and pelvic tilt (PT). ASD patient's deformities were classified as either Mild or Severe based on the SRS-Schwab ASD classification.RESULTSSevere ASD patients had significantly larger dynamic maximum and minimums for SVA, TPA, LL, and PT (all p<.05) compared with Mild ASD patients. ASD patients exhibited little difference in dynamic alignment compared with healthy subjects. Only PT had a significant difference in dynamic RoM compared with healthy (p<.001).CONCLUSIONSMild and Severe ASD patients exhibited similar global dynamic alignment measures during gait and had comparable RoM to healthy subjects except with greater PT and reduced spatiotemporal performance which may be key compensatory mechanisms for dynamic stabilization.  相似文献   
55.
Background ContextPrevious studies have reported conflicting results for the relationships between anthropometric adiposity indexes and bone mineral density, based on dual-energy X-ray absorptiometry (DXA). However, few studies were published based on quantitative computed tomography (QCT), especially for Chinese population.PurposeTo evaluate the associations of spine bone mineral density (BMD) with body mass index (BMI), waist circumstance (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) using QCT.Study Design/SettingA Cross-sectional study.Patient SampleAround 3,457 participants in multiple communities across 7 administrative regions of China.Outcome MeasuresSpine BMD was measured using QCT, and the classification of osteoporosis was defined as follows: 1) osteoporosis if BMD <80mg/cm3, 2) osteopenia if BMD 80–119 mg/cm3, and 3) normal bone mass if BMD≥120 mg/cm3.MethodsThis study was conducted using convenient sampling between 2013 and 2017. Multivariable linear regression model and logistic regression models were used for the associations of continuous and categorical BMD, respectively.ResultsAround 3,405 participants were included in the final analyses, including 1,272 males and 2,133 females, with spine BMD of 111.00±35.47 mg/cm3 and 99.38±40.60 mg/cm3, respectively. Spine BMD decreased significantly with the increase of ABSI in females (adjusted β, ?5.74; 95% confidence interval [CI], ?8.50 to ?2.98), and this trend also was kept in females aged at less than 60 years (adjusted β, ?14.54; 95% CI, ?20.40 to ?8.68), and females with age ≥60 years (adjusted β, ?7.59; 95% CI, ?10.91 to ?4.28). However, this inverse association was observed only in males with age ≥ 60 years (adjusted β, ?5.19; 95% CI, ?10.08 to ?0.29). Except ABSI, negative associations of Spine BMD with WC (adjusted β, ?0.46; 95% CI, ?0.77 to ?0.15), WHR (adjusted β, ?6.25; 95% CI, ?10.63 to ?1.86), WHtR (adjusted β, ?6.80; 95% CI, ?11.63 to ?1.97) were shown in females aged at <60 years, and positive association with BMI in males with age ≥60 years (adjusted β, 0.92; 95% CI, 0.29–1.55).ConclusionsABSI had more remarkable association with spine BMD, compared with the other four indexes.  相似文献   
56.
本文简要介绍一种基于PC微机的实时数字减影系统,文中对系统的组成、工作原理、曝光脉冲的产生及其对X线机的控制作了较详细的论述,同时对系统的软件功能做一简要介绍。该系统已用于国内几十家医院对西门子公司早期生产的X线机的升级改造,取得了较好的社会效益和经济效益。  相似文献   
57.
老年人低位硬膜外麻醉围术期自主神经功能的变化   总被引:4,自引:0,他引:4  
目的:应用心率变异性(HRV)分析仪监测评估低位硬膜外麻醉围术期自主神经的改变。方法:选择低位硬膜外麻醉下择期手术患者20例,ASAⅠ-Ⅱ级,按年龄分为老年组和年轻组,每组10例,观察术前1d、麻醉完善后切皮前、切皮后30min、术后2h,1d,3d,7d处时相点的心率(HR)、平均动脉压(MAP)以及HRV分析各成分变化。结果:围术期老年组HRV显示RMSSD(相邻RR间期差值均方根)、总频(TP)、低频(LF)、代频标化(LFnorm)均呈显著性下降,同时伴有心率减慢、平均动脉下降。年轻组TP和LF在麻醉完善后切皮前、术后2h,1d下降显著,于术后3d恢复,而R和MAP在围术期无显著改变。两组两比较,老年组TP和LF在麻醉后各时相占 明显低于年轻组(P<0.01)。老年组高频(HF)及高频标化(HFnorm)在麻醉给药后切皮瓣均无明显变化,但在术中和术后各时相点的下降,而年轻组仅切皮后30min,出现一过性下降。结论HRV可较好地评估围术期机体自神经变化;术期麻醉和手术创伤均可使机体自主神系统调节受损,尤其老年人受损程度大,恢复慢,恢复慢,术后1周仍不能完全恢复。  相似文献   
58.
探讨过氧化物所致肝细胞凋亡时Fas基因表达与Ca^2+流变化的相互关系。方法应用全细胞膜片错单细胞逆转录聚合酶链反应技术进行H2O2诱导人类正常肝细胞LO2细胞FasmRNA表达的单细胞分析,应用全细胞膜片错显微荧光单细胞胞浆游离钙浓度测量技术、流式细胞术、扫描电镜观察同期瞬时Ca^2+流变化及早期凋亡(Annexin-V)细胞指数和细胞膜变化。结果H2O2作用2h单个LO2细胞电泳图分析可见Fa  相似文献   
59.
研究持续灌注温血停搏液对心肌的保护作用,探讨理想的心肌保护策略,方法69只猫随机分为对照组、损伤组和保护组。观察测各组不同时间点心功能、心肌细胞膜ATPase活性心肌细胞膜蛋白颗粒的形态变化。结果组Ⅰ各时间点各项指标无明显变化。升主动脉阻断期间,组Ⅱ-ⅢaK-ATPase活性均显著下降(ACC15min us ACC60min,P〈0.01),组ⅡCaMg-ATPase活性单位面积心肌细胞膜蛋白颗  相似文献   
60.
目的:应用微渗透压泵将碱性成纤维细胞因子(bFGF)导入耳蜗,观察其对庆大霉素所致活体耳蜗毒性的拮抗作用。方法:豚鼠皮下注射庆大霉素造成耳毒性聋的模型。实验将bFGF以微渗透压泵导入实验组右耳蜗,对照组右耳以微渗透压泵导入等量PBS。用扫描电镜观察两组动物右耳毛细胞的损伤,同时比较其用药前后ABR听阈的改变。结果:对照组右耳的损伤明显重于实验组。结论:采用微渗透压泵耳蜗灌注bFGF对庆大霉素所致豚鼠的耳蜗损伤有拮抗作用。  相似文献   
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