应变成像评价犬左心室急性心肌缺血边缘区跨壁力学状态

目的 应用应变成像观察犬左室急性心肌缺血边缘区不同层次心肌径向峰值应变及应变达峰时间,评价其跨壁力学特征.方法 9只Beagle犬开胸结扎左冠状动脉前降支建立心肌缺血模型,分别于基础状态、缺血状态采集连续3个心动周期的左室心尖二维短轴观图像存于TDI-Q工作站,在脱机状态下应用软件衍生M型组织多普勒速度图,采样分析基础状态、缺血后边缘区的节段整体、心内膜下心肌、中层心肌及心外膜下心肌(subepicardium,subepi)的径向峰值应变(S)及达峰时间(T).统计数据分析采用两独立样本t检验和配对t检验以及直线相关分析.结果 边缘区心内膜下心肌峰值应变较基础状念值降低(P<0.05),中层心肌峰值应变与基础状态值相比无明显差异(P>0.05),心外膜下心肌峰值应变较基础状态值增高(P<0.05);节段整体达峰时间以及各层次达峰时间延长(P<0.05);同时观察到基础状态心内膜下层心肌及中层心肌分别与其节段整体的峰值应变有较好的相关性(r=0.617,r=0.556,P均<0.01),而梗死边缘区这种相关性消失(r=0.287,r=0.243.P均>0.05).结论 急性心肌缺血后,边缘区呈心内膜下层心肌峰值应变降低、心外膜下层心肌峰值应变增高和各层次达峰时间延长,该跨壁力学状态是缺血区域和非缺血区域不同层次心肌力学机制相互作用的结果.推测此力学状态是决定心室重构进程以及最终向缺血性心肌病演变的重要触发机制之一.     

超声斑点追踪技术测量正常人左室短轴径向应变的初步研究

目的 应用超声二维应变成像评价正常人左室短轴局部心肌收缩期峰值应变.方法 健康志愿者21例,获取左室短轴二尖瓣环水平、乳头肌水平、心尖水平二维图像,测定左室短轴二尖瓣水平、乳头肌水平、心尖水平各心肌节段心内膜下、心外膜下及整体心肌径向收缩期峰值应变.结果 (1)正常人左室短轴各水平间心肌整体径向峰值应变相互比较,乳头肌水平＞二尖瓣水平＞心尖水平,在大多数节段,P＜0.05,各水平间差异有统计学意义.(2)正常人左室短轴各水平间心内膜下心肌径向峰值应变相互比较,二尖瓣水平及乳头肌水平均大于心尖水平,在大多数节段,P＜0.05,差异有统计学意义,二尖瓣水平及乳头肌水平间无显著性差异.(3)正常人左室短轴各水平间心外膜下心肌径向峰值应变相互比较,三者间无显著性差异.结论 超声斑点追踪技术能准确评价左室心肌径向应变,并评价室壁局部心肌功能,为心肌疾病的定位诊断提供新的方法.     

超声斑点追踪技术评价正常人左室短轴收缩功能

目的 应用超声斑点追踪成像(STI)评价正常人左室心肌短轴收缩功能.方法 68例正常人记录二尖瓣、乳头肌及心尖水平左室短轴连续3个心动周期的二维灰阶图像,使用Qlab 6.0工作站进行脱机分析,系统自动将左室短轴分为前间隔、前壁、侧壁、后壁、下壁、后间隔6段,共计18个节段,将左室壁等分为心内膜下感兴趣区及心外膜下感兴趣区,应用STI技术分析感兴趣区的圆周及径向收缩期峰值应变.结果 心内膜层心肌各室壁节段收缩期峰值应变均高于心外膜层心肌(P<0.05),同一水平前室间隔圆周应变高于其它节段,径向应变在不同节段分布比较一致.结论 超声斑点追踪成像技术因其不受声束角度限制的优点,可用于评价左室局部心肌收缩功能.     

超声斑点追踪成像技术评价正常人左室心肌周向收缩功能

目的 应用超声斑点追踪成像(STI)评价正常人左室心肌周向收缩功能.方法 35例正常人取二尖瓣、乳头肌及心尖水平短轴连续3个心动周期的二维灰阶图像,使用Qlab 6.0工作站进行脱机分析,系统自动将左室短轴分为前间隔、前壁、侧壁、后壁,下壁、室间隔6段,共计18个节段,将左室壁等分为心内膜下感兴趣区及心外膜下感兴趣区,应用STI技术分析感兴趣区的周向收缩期峰值应变.结果 心内膜层心肌各室壁节段周向收缩期峰值应变均高于心外膜层心肌(P<0.05),尤以前间隔和后壁节段差异更为显著(P<0.01).结论 超声斑点追踪成像技术不受声束角度的限制,可用于评价左室局部心肌的周向收缩功能.     

超声二维应变成像评价肥厚型心肌病患者左心室收缩功能

目的应用超声二维应变成像评价肥厚型心肌病（HCM）患者左室局部心肌收缩功能。方法HCM患者21例，正常对照者21例，获取左室短轴观二尖瓣环水平、乳头肌水平、心尖水平，心尖位四腔观、二腔观及左室长轴观的二维图像，测定左室心尖位二维纵向应变收缩期峰值，左室短轴二尖瓣水平、乳头肌水平、心尖水平各心肌节段心内膜下、心外膜下及整体心肌径向收缩期峰值应变。结果①HCM组与正常组心尖位二维纵向收缩期峰值应变比较，HCM组绝大多数节段心肌峰值应变显著降低（P〈0．05）；②HCM组与正常组左室短轴心内膜下心肌二维径向收缩期峰值应变比较，HCM组心肌收缩期峰值应变明显减低，二尖瓣水平及乳头肌水平绝大多数节段差异有统计学意义（P〈0．05）；③HCM组与正常组左室短轴心外膜下心肌二维径向收缩期峰值应变比较，绝大多数节段差异无统计学意义；④HCM组与正常组左室短轴心肌整体二维径向收缩期峰值应变比较，HCM组绝大多数节段心肌峰值应变显著降低（P〈0.05），尤以肥厚节段较多的乳头肌水平明显（P〈0．01）。结论HCM患者肥厚与非肥厚节段于左室纵向及左室短轴径向收缩功能均受损，并且径向收缩功能受损以心内膜下心肌为主。     

超声二维斑点追踪技术对左室心肌周向收缩功能的研究

目的利用超声二维斑点追踪技术(2DS)评价实验动物猪左室心肌周向收缩功能。方法25只猪开胸后取中部水平左室短轴切面,采集连续3个心动周期二维灰阶图像,并与左室压力曲线同步(±dp/dt)。使用EchoPAC软件包进行脱机分析。运用2DS技术测量左室心内膜层和心外膜层6个心肌节段的周向收缩期峰值应变。结果心内膜层各室壁节段周向收缩期峰值应变均高于心外膜层(P<0.01),尤以前间隔、侧壁、下壁和室间隔节段差异更为显著(P<0.0001)。此外,心内膜层和心外膜层各节段心肌周向收缩期峰值应变均与左室dp/dt相关性良好。结论超声二维斑点追踪技术因其不受声束角度限制的优点,能准确地评价左室局部心肌的周向收缩功能。     

不同激动顺序犬左心室收缩期跨壁扭转运动的超声实验研究

目的 应用斑点追踪成像技术评价不同电机械激动顺序下收缩期左室跨壁扭转运动特征.方法 5只开胸比格犬模型,分别在基础(BASE),右心耳(RAA)、右室心尖(RVA)、左室侧壁(LVL)和左室心尖(LVA)起搏状态采集左室心尖、基底短轴和四腔心图像.QLAB软件分析短轴切面心内膜下、心外膜下和整体旋转角度(RA)及节段角位移(AE),计算左室扭转及射血分数(EF).结果 ①RAA组心内膜下、心外膜下和整体扭转,基底和心尖水平心内膜下、心外膜下和整体RA及AE与BASE组间差异无统计学意义(P>0.05);②RVA组心内膜下、心外膜下和整体扭转及LVA组心内膜下和整体扭转均小于RAA组(P<0.05);RVA和LVA组基底心内膜下、心外膜下和整体RA均小于RAA组(P<0.05);③心室起搏后起搏位点相邻节段心肌AE小于RAA组(P<0.05);④BASE状态心内膜下扭转大于心外膜下(P<0.05),起搏仅呈心内膜下扭转大于心外膜下趋势(P>0.05);⑤BASE组与RAA组心外膜下和整体扭转与左室EF呈正相关;基底心内膜下、心外膜下和整体RA与左室EF呈正相关.结论 RVA及LVA起搏明显抑制左室跨壁扭转运动;正常激动顺序下左室整体及外膜下心肌扭转和基底旋转运动与左室EF关系密切.     

实时剪切波弹性成像测量猪离体心脏心肌剪切模量

目的 研究猪离体心脏左室壁心肌剪切模量大小的分布规律.方法 取4枚新鲜离体猪心,采用实时剪切波弹性成像技术,在探头方向与左室长轴或短轴平行两种情况下,分别测量各心脏左室前壁心外膜下层、中层和心内膜F层心肌的剪切模量.结果 探头方向与左室长轴平行时,测得左室前壁中部心外膜下层、中层、心内膜下层心肌剪切模量分别为( 46.04±17.07)kPa,(87.70±29.67) kPa,(115.73±30.04)kPa;探头方向与左室短轴平行时,心外膜下层、中层、心内膜下层心肌剪切模量分别为(78.71±26.48)kPa,(77.08±34.00)kPa,(70.69±41.38)kPa.结论 通过实时剪切波弹性成像技术测得的左室壁心外膜下层、中层及心内膜下层心肌剪切模量大小不同,且同一部位心肌在切面不同时剪切模量大小也有差异.     

心肌运动速度和应变率评价不同程度心肌缺血

目的应用定量组织速度成像(QTVI)技术检测犬不同程度急性心肌缺血前后左室前壁心肌运动速度和应变率(SR)的变化，探寻一种能定量、敏感、无创性地评价左室局部收缩及舒张功能的新方法。方法将9只开胸犬冠状动脉左前降支(LAD)血流减少造成中度、重度心肌缺血模型，取左室乳头肌水平短轴观，以QTVI分别检测不同程度缺血时左室前壁心内膜下心肌和心外膜下心肌收缩期峰值运动速度(Vsendo、Vsepi)、舒张早期峰值运动速度(Veendo、Veepi)，并计算出收缩期SR(SRs)和舒张早期SR(SRe)。结果基础状态下，心内膜下心肌速度高于心外膜下心肌速度。缺血导致左室前壁Vsendo、Veendo、Veepi和SRe均显著下降，尽管Vsepi降低不明显，但SRs降低显著。结论心肌运动速度和应变率能敏感地评价不同程度实验性心肌缺血，比常规的方法(运动幅度和室壁增厚率)更敏感。     

ICK技术评价冠心病冠状动脉支架置入术前后左心室节段舒张功能

目的运用定量彩色室壁运动分析技术(ICK)评价冠心病支架置入前后左心室节段舒张功能。方法观察20例正常人和37例冠心病患者胸骨旁左室乳头肌短轴观、心尖四腔、两腔观各节段心肌舒张期心内膜位移引起彩阶的变化,并运用ICK定量分析软件计算出心内膜于舒张早期30%时间内位移的面积占整个舒张期内膜位移面积的百分比,即心内膜位移指数(CK-DI)。结果正常组左前降支、左回旋支和右冠状动脉供血区的CK-DI分别为77%±12%、82%±11%、74%±13%,各区之间无统计学差异,病变节段的CK-DI明显低于正常组,且均小于55%。术后1至3个月,286个再灌注心肌节段CK-DI呈逐渐上升趋势,16个未再灌注心肌节段的CK-DI明显低于再灌注节段。结论ICK定量分析软件能准确、定量地检测出缺血心肌舒张功能,为临床心功能评价及判断心肌缺血提供新指标。     

Complications of regional anesthesia

Perioperative nerve injuries have long been recognized as a complication of regional anesthesia. Although severe or disabling neurologic complications are rare, recent epidemiologic series suggest the frequency of some serious complications is increasing. Risk factors contributing to neurologic deficit after regional anesthesia includes neural ischemia (hypothesized to be related to the use of vasoconstrictors or prolonged hypotension), traumatic injury to the nerves during needle or catheter placement, infection, and choice of local anesthetic solution. In addition, postoperative neurologic injury due to pressure from improper patient positioning or from tightly applied casts or surgical dressings, as well as surgical trauma are often attributed to the regional anesthetic. Patient factors such as body habitus and pre-existing neurologic dysfunction may also contribute. The safe conduct of regional anesthesia involves knowledge of the laboratory studies, large patient series as well as individual case reports of neurologic deficits following regional anesthetic techniques. Prevention of complications, along with early diagnosis and treatment are important in the management of regional anesthetic risks.     

Intravenous regional block with lidocaine for treatment of complex regional pain syndrome

OBJECTIVES: The goal of this article is to report the successful treatment of a patient with complex regional pain syndrome (CRPS) type 1 involving the hand with the use of an intravenous regional block. METHODS: The patient was a 35-year-old woman who developed CRPS during conservative therapy for a metacarpal fracture. An intravenous regional block with lidocaine alone, using a two-tourniquet technique, was delivered 10 times for at least 40 minutes. The first five treatments were given twice a week and the next five were delivered weekly. All affected joints, including the wrist, were manipulated without undue force. Functional physical measurements were assessed, including range of motion and performance of fine and gross motor tasks. RESULTS: The visual analog scale scores for pain declined from 10 to 0 after treatment. Use of a pen, a pair of chopsticks, and a hammer improved, and edema decreased. CONCLUSIONS: Intravenous regional block with lidocaine was well tolerated and associated with relief in this case of CRPS type 1.     

Complex regional pain syndrome

Complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy, is a regional, posttraumatic, neuropathic pain problem that most often affects 1 or more limbs. Like most medical conditions, early diagnosis and treatment increase the likelihood of a successful outcome. Accordingly, patients with clinical signs and symptoms of CRPS after an injury should be referred immediately to a physician with expertise in evaluating and treating this condition. Physical therapy is the cornerstone and first-line treatment for CRPS. Mild cases respond to physical therapy and physical modalities. Mild to moderate cases may require adjuvant analgesics, such as anticonvulsants and/or antidepressants. An opioid should be added to the treatment regimen if these medications do not provide sufficient analgesia to allow the patient to participate in physical therapy. Patients with moderate to severe pain and/or sympathetic dysfunction require regional anesthetic blockade to participate in physical therapy. A small percentage of patients develop refractory, chronic pain and require long-term multidisciplinary treatment, including physical therapy, psychological support, and pain-relieving measures. Pain-relieving measures include medications, sympathetic/somatic blockade, spinal cord stimulation, and spinal analgesia.     

复杂区域疼痛综合征

目的：总结并分析复杂区域疼痛综合征发生机制．分类和治疗方法，促进对此疾病的进一步研究。资料来源：应用计算机检索Medline 1980-01／2005—06关于复杂区域疼痛综合征的文章。检索词“complex regional pain syndrome，reflex sympathetic dystrophy（RSD），casualgia等”并限定文章的语种为英文。资料选择：对检索到的160多篇资料进行初审，纳入标准：关于复杂区域疼痛综合征的概念、分类、发病机制和治疗方法。排除标准：排除重复性研究。资料提炼：共收集到关于复杂区域疼痛综合征的文献53篇。其中研究内容相似的，以近10年内发表的文章优先。对符合标准的29篇文献进行分析。资料综合：复杂区域疼痛综合征是机制不清楚的难治性神经病理性疼痛疾病之一，目前认为其产生和维持是多种因素共同作用的结果。根据与交感神经的关系和有无明确的神经损伤分为Ⅰ型和Ⅱ型。临床表现以患肢疼痛和痛觉超敏、自主神经功能紊乱、运动功能和营养异常等为特征。康复、疼痛治疗和心理治疗是复杂区域疼痛综合征的重要治疗手段。结论：复杂区域疼痛综合征病因十分复杂、治疗极其困难，需要大量的临床和实验研究来探索其发病机制，寻求有效的预防和治疗方法。     

Multisite regional telephone care

A multisite, regional telephone-care program staffed by advance practice and critical care nurses has improved patient care and reduced unnecessary clinic and emergency room visits. It allows patients to access the health care system and receive expert advice through the use of the telephone, 24 hours per day, 7 days per week. Computerized patient medical records from eight hospitals and 31 clinics are available to a registered nurse so that informed decisions can be made. The RN records the patient's concern and intervention directly into the patient's medical record, which is transmitted to the primary care provider in real time.