Risk factors associated with surgical site infection and the development of short-term complications in macaques undergoing indwelling vascular access port placement

BACKGROUND: Risk factors associated with surgical site infection (SSI) and the development of short-term complications in macaques undergoing vascular access port (VAP) placement are evaluated in this study. METHODS: Records from 80 macaques with VAPs were retrospectively reviewed. Logistic regression was used to identify factors associated with short-term post-operative complications. RESULTS: The primary outcome was SSI, which occurred in 21.6% (52.6% in the first 12 months vs. 13% thereafter) of procedures. SSI was associated with major secondary complications including VAP removal (11.4%), wound dehiscence (5.7%), and mechanical catheter occlusion (5.7%). In multivariate modeling, only surgical program progress was a statistically significant predictor of SSI, while animal compliance had a slightly protective effect. CONCLUSIONS: Vascular access ports have a moderate risk of complications, provided the surgical program optimizes best practices. Under complex experimental conditions, VAPs represent an important refinement, both improving animals' overall well-being and environment and reducing stress.     

Task-based phantom evaluation of cardiac catheterization imaging modes

This study aimed to quantify the dose and quality of the preprogrammed imaging modes on two cardiac angiography devices (Philips Allura FD10 Clarity and Allura FD10) using a task-specific in-house phantom, and to discuss the appropriateness of the pre-programmed settings. A Figure of Merit (FOM), defined as the squared Signal Difference to Noise Ratio (SDNR) divided by Entrance Surface Air Kerma (ESAK), was calculated for phantom inserts with different sizes and concentrations of iodine, as well as tin foils. For the Allura FD10 Clarity device, the low dose fluoroscopic mode was found to be very dose efficient, while the available ciné modes should only be used for cases with high demand for contrast and temporal resolutions. For both devices, the basic beam spectrum of the low dose fluoroscopic mode should be explored for use on other imaging modes. Ciné modes for the Allura FD10 device differ only by their spatial resolution characteristics and have almost identical dose per frame. This study also found that tin may not be a suitable replacement for iodine for research purposes due to mismatching SDNR. The number of recommendations formulated for these two devices suggests that comparative dose and image quality tests of all routinely used imaging modes should be an obligatory part of the physicists’ acceptance testing.     

超声引导下肝内胆管置管治疗肝内胆管结石并发梗阻的临床效果观察

目的:探究超声引导下肝内胆管置管治疗肝内胆管结石并发梗阻的临床效果和安全性。方法:选择2014年1月至2018年1月于我院接受治疗的98例肝内胆管结石并发梗阻患者为研究对象,将患者按照入院顺序统一编号后,根据随机数字表法进行分为实验组与对照组,每组各49例患者。对照组患者于常规X线引导下行肝内胆管置管治疗,实验组患者在超声引导下实施肝内胆管置管治疗,对比两组患者穿刺次数、手术时间、术后并发症的发生情况,并对两组患者随访3个月,比较其结石残余率及治疗效果。结果:(1)实验组患者穿刺次数及操作时间均显著少于对照组(P0.05);(2)实验组患者术后各类并发症发生率为4.08%,明显低于对照组(20.41%,P0.05);(3)对照组患者后3个月的结石残余率为14.29%(7/49),实验组为2.04%(1/49),显著低于对照组(P0.05);(4)术后3个月,实验组患者治疗总有效率为97.96%,明显高于对照组(81.63%,P0.05)。结论:与常规X线引导下行肝内胆管置管治疗相比,超声引导下肝内胆管置管在治疗肝内胆管结石并发梗阻中具有较更好的治疗效果和安全性。     

改良型大鼠鞘内穿刺置管针及导管末端注药装置在大鼠鞘内置管术中的应用研究

目的: 介绍一种大鼠鞘内穿刺置管针及导管末端注药装置在大鼠鞘内置管术中的应用,并评价其可行性和有效性。方法: 60只清洁级SD雄性大鼠,随机分为常规组(C组,n=30)和改良组(M组,n=30)。C组使用尖端磨平的20G针头穿刺置管,置入微量导管后于大鼠颈部两耳间穿出,留置2～3 cm,导管末端热封后游离放置;M组使用鞘内穿刺置管针进行操作,并以微量注射旋塞保护鞘内导管末端。术后1 d评估两组大鼠运动功能,分别于术后1、3、7、14、21 d进行利多卡因试验,至30 d鞘内注射亚甲蓝定位,观察并记录鞘内导管位置;记录两组鞘内给药操作时间;测定术前及术后上述时点两组大鼠机械刺激缩足反应阈值 (PWT);术前及术后一周行旷场实验,评估两组大鼠自主活动情况。结果: 运动功能分级:C组Ⅰ级75.9%,Ⅱ级20.7%,Ⅲ级3.4%,M组Ⅰ级96.7%,Ⅱ级3.3%,M组运动功能分级Ⅰ级占比率显著高于C组(P＜0.05);利多卡因实验和亚甲蓝定位导管位置显示:C组分别于置管后第14日、21日各有1例脱落,至置管后第30日,共有4例导管脱落,而M组导管均在位,两组相比有统计学差异(P＜0.05);M组鞘内注药操作时间多在1 min左右,而C组超过3 min,两组相比有显著统计学差异(P＜0.01);PWT变化情况:两组置管后一周内PWT有波动,第3日降至最低,两组与术前相比均有显著差异(P＜ 0.05),置管后7 d逐渐恢复至术前水平,两组间比较无差异;旷场实验:M组置管前后在总路程、中央区活动路程以及运动时间和速度等方面均无差异,两组间各指标之间相比也无差异。结论: 改良型大鼠鞘内穿刺置管针较常规穿刺置管工具穿刺效能一致,但对大鼠运动功能影响小;微量注射旋塞能有效避免鞘内导管脱出,快速便捷完成注药,并对大鼠自主活动无影响,值得进一步推广使用。     

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions of individuals worldwide ^1-3. The rapid, irregular, and disordered electrical activity in the atria gives rise to palpitations, fatigue, dyspnea, chest pain and dizziness with or without syncope ^{4, 5}. Patients with AF have a five-fold higher risk of stroke ⁶.Oral anticoagulation (OAC) with warfarin is commonly used for stroke prevention in patients with AF and has been shown to reduce the risk of stroke by 64% ⁷. Warfarin therapy has several major disadvantages, however, including bleeding, non-tolerance, interactions with other medications and foods, non-compliance and a narrow therapeutic range ^8-11. These issues, together with poor appreciation of the risk-benefit ratio, unawareness of guidelines, or absence of an OAC monitoring outpatient clinic may explain why only 30-60% of patients with AF are prescribed this drug ⁸.The problems associated with warfarin, combined with the limited efficacy and/or serious side effects associated with other medications used for AF ^12,13, highlight the need for effective non-pharmacological approaches to treatment. One such approach is catheter ablation (CA), a procedure in which a radiofrequency electrical current is applied to regions of the heart to create small ablation lesions that electrically isolate potential AF triggers ⁴. CA is a well-established treatment for AF symptoms ^{14, 15}, that may also decrease the risk of stroke. Recent data showed a significant decrease in the relative risk of stroke and transient ischemic attack events among patients who underwent ablation compared with those undergoing antiarrhythmic drug therapy ¹⁶.Since the left atrial appendage (LAA) is the source of thrombi in more than 90% of patients with non-valvular atrial fibrillation ¹⁷, another approach to stroke prevention is to physically block clots from exiting the LAA. One method for occluding the LAA is via percutaneous placement of the WATCHMAN LAA closure device. The WATCHMAN device resembles a small parachute. It consists of a nitinol frame covered by fabric polyethyl terephthalate that prevents emboli, but not blood, from exiting during the healing process. Fixation anchors around the perimeter secure the device in the LAA (Figure 1). To date, the WATCHMAN is the only implanted percutaneous device for which a randomized clinical trial has been reported. In this study, implantation of the WATCHMAN was found to be at least as effective as warfarin in preventing stroke (all-causes) and death (all-causes) ¹⁸. This device received the Conformité Européenne (CE) mark for use in the European Union for warfarin eligible patients and in those who have a contraindication to anticoagulation therapy ¹⁹.Given the proven effectiveness of CA to alleviate AF symptoms and the promising data with regard to reduction of thromboembolic events with both CA and WATCHMAN implantation, combining the two procedures is hoped to further reduce the incidence of stroke in high-risk patients while simultaneously relieving symptoms. The combined procedure may eventually enable patients to undergo implantation of the WATCHMAN device without subsequent warfarin treatment, since the CA procedure itself reduces thromboembolic events. This would present an avenue of treatment previously unavailable to patients ineligible for warfarin treatment because of recurrent bleeding ²⁰ or other warfarin-associated problems.The combined procedure is performed under general anesthesia with biplane fluoroscopy and TEE guidance. Catheter ablation is followed by implantation of the WATCHMAN LAA closure device. Data from a non-randomized trial with 10 patients demonstrates that this procedure can be safely performed in patients with a CHADS₂ score of greater than 1 ²¹. Further studies to examine the effectiveness of the combined procedure in reducing symptoms from AF and associated stroke are therefore warranted.     

An Orthotopic Bladder Cancer Model for Gene Delivery Studies

Bladder cancer is the second most common cancer of the urogenital tract and novel therapeutic approaches that can reduce recurrence and progression are needed. The tumor microenvironment can significantly influence tumor development and therapy response. It is therefore often desirable to grow tumor cells in the organ from which they originated. This protocol describes an orthotopic model of bladder cancer, in which MB49 murine bladder carcinoma cells are instilled into the bladder via catheterization. Successful tumor cell implantation in this model requires disruption of the protective glycosaminoglycan layer, which can be accomplished by physical or chemical means. In our protocol the bladder is treated with trypsin prior to cell instillation. Catheterization of the bladder can also be used to deliver therapeutics once the tumors are established. This protocol describes the delivery of an adenoviral construct that expresses a luciferase reporter gene. While our protocol has been optimized for short-term studies and focuses on gene delivery, the methodology of mouse bladder catheterization has broad applications.     

双套管水柱法监测家兔平均动脉压

目的探讨双套管水柱的构成,用双套管水柱法测定家兔的平均动脉压,观察静脉麻醉对家兔血压的影响。方法双套管水柱的组成和使用,并在局麻或全麻下,用双套管水柱法及RM6000多导生理记录仪有创连续监测家兔平均动脉压,用T检验分析两种方法所测数据。结果静脉麻醉后家兔的平均动脉压从术前（149.88±1.77）cmH2O（局麻清醒安静状态下）下降到（127.60±4.09）cmH2O,有显著差异（P〈0.05）。双套管水柱法及RM6000多导生理记录仪测得结果间无显著性差异（P〉0.05）。结论用双套管水柱法可准确地、动态地监测麻醉家兔平均动脉压。静脉麻醉对家兔血压有明显的影响。     

Optimization of dose and image quality of paediatric cardiac catheterization procedure

The purpose of this study is to quantify the quality of the available imaging modes for various iodine-based contrast agent concentration in paediatric cardiology. The figure of merit (FOM) was defined as the squared signal to noise ratio divided by a patient dose related parameter. An in house constructed phantom simulated a series of vessel segments with iodine concentrations from 10% or 30 mg/cc to 16% or 48 mg/cc of iodine in a blood plasma solution, all within the dimensional constraints of a paediatric patient. The phantom also used test inserts of tin (Sn). Measurements of Entrance Surface Air Kerma (ESAK) and exit dose rate were performed along with calculations of the signal-to-noise ratio (SNR) of all the objects. A first result showed that it was favourable to employ low dose fluoroscopy mode and lower frame rate modes in cine acquisition if dynamic information is not critical. Normal fluoroscopy dose mode provided a considerably higher dose level (in comparison to low dose mode) with only a slight improvement in SNR. Higher frame rate cine modes should be used however when the clinical situation dictates so. This work also found that tin should not be intended as iodine replacement material for research purposes due to the mismatching SNR, particularly on small vessel sizes.     

心力衰竭的物理诊断现状

心力衰竭是各种心脏疾病发展的终末阶段,及时准确的确诊心力衰竭、辨别其病情变化可进一步指导治疗及缩短住院时间,并为心力衰竭的预后评价提供参考依据。目前,确诊心力衰竭主要基于患者的临床症状、体征及各种影像学表现、生化指标等做出综合评价,而物理诊断是诊断心力衰竭不可或缺的依据。心脏彩超已应用于临床多年,可从多个层面评估左室充盈压,是初步评价心脏功能的便捷措施。核心脏病学可评估心脏交感神经支配的区域及激活模式,预测心力衰竭的发病率和死亡率。心脏磁共振可用于进行危险分层及确定是否适合手术/介入治疗。此外,心脏CT及心导管术也是用于评价心功能的常见物理检查方法。本文主要总结了目前各种诊断心力衰竭的物理诊断方法的最新进展,以进一步指导临床实践。