经食管实时三维超声心动图评价房性心律失常对二尖瓣结构和功能的影响

目的:应用经食管实时三维超声心动图(RT-3D-TEE)技术,探讨房性心律失常对二尖瓣结构和功能的影响.方法:选取2018年6月~2019年6月本院收治的房性心律失常拟行射频消融的患者49例纳入观察组,另外选取21例正常窦性心律者作为对照组,所有患者均行经胸超声心电图(TTE)和经食管实时三维超声心动图(RT-3D-TEE)检查,将两组患者的瓣环投影面积(A2D)、瓣环周长(C3D)、瓣环高度(H)、瓣环前后径(DAP)、瓣环前外侧至后内侧直径(DAIPm)、左室射血分数(LVEF)、左心房前后径(Lad)等参数进行比较,并分别计算对合面积和对合指数,之后采取二项Logistic回归分析或逐步线性回归对各参数及临床因素与对合指数的相关性进行分析.结果:两组患者在LVEF和对合面积方面的比较无明显差异(P>0.05),在A2D、C3D、H、DA、PDAIPm、Lad方面的比较,房性心律失常组患者明显高于正常窦性心律组患者(P<0.05),且观察组患者的对合指数明显降低(P<0.05).将49例观察组患者以不同心律失常类型分为持续性房颤、阵发性房颤、房扑、混合型房性心律失常4个亚组,采用单因素方差分析,发现在LVEF、C3D、Lad、对合指数方面的比较,各亚组间无明显差异(P>0.05).采用二项Logistic回归分析发现,女性是导致对合指数低的危险因素,另外对合指数较低、房性心律失常是导致二尖瓣返流的重要因素.结论:房性心律失常对患者二尖瓣的A2D、C3D、H、DA、PDAIPm、Lad等都会造成较大影响,从而降低对合指数,影响二尖瓣的正常功能,导致二尖瓣返流的发生.     

Upper limb nerve blocks

Brachial plexus blockade is used for a variety of upper limb surgical procedures. Ultrasound guidance is generally considered to be the gold-standard technique, although large-scale studies examining efficacy and complications of ultrasound-guided techniques compared with nerve stimulation are still needed. Interscalene block remains the approach of choice for shoulder surgery, although phrenic nerve blockade is common even using low volumes of local anaesthetic. Of the currently available studies comparing the other approaches, there seems to be little difference in efficacy between axillary, supraclavicular and infraclavicular approaches for elbow, forearm and hand surgery when equivalent levels of expertise are used. The major features influencing block choice and performance are discussed.     

微滴式数字PCR和实时荧光定量PCR对新型冠状病毒肺炎患者不同时间血便尿中核酸检测结果初步探讨

目的 分析微滴式数字PCR(droplet digital PCR, ddPCR)和实时荧光定量PCR(quantitative real-time PCR,qPCR)的核酸检测结果,比较两种方法检测各类样本的差异性,为改进新型冠状病毒核酸检测方案提供数据支持。 方法 利用ddPCR和qPCR技术对已经确诊的3例新型冠状病毒肺炎患者发病不同时间的全血、尿液、粪便共22份标本进行新型冠状病毒核酸检测。 结果 两种方法对人保守区域基因扩增结果一致:全血标本信号最强,尿液次之,粪便最少;ddPCR在1份全血,1份尿液,5份粪便中检出ORF-1ab和N基因的阳性微滴,qPCR仅在3份粪便中检出上述基因,漏检的3个标本基因拷贝数平均浓度为128 copies/ml;ddPCR在发病<5、5~15、>15 d的各类标本中都有检出,qPCR检出以中晚期为主;重症病例用ddPCR均可测到阳性微滴,qPCR检测的各类标本均为阴性;轻症病例的各类标本中qPCR只有粪便核酸检测阳性,ddPCR检出率高于qPCR。 结论 ddPCR可以有效克服qPCR 灵敏度不足的难题,是对qPCR 的有益补充,尤其是针对病毒载量比较低的血液、尿液和可疑的粪便或肛拭子标本,适用于早期感染的判断及患者治愈后出院诊断。     

Bupropion Overdose Complicated by Cardiogenic Shock Requiring Vasopressor Support and Lipid Emulsion Therapy

BackgroundBupropion overdose is a commonly encountered presentation in the emergency department (ED). While the majority of cases resolve with supportive care, serious adverse effects, including seizures, cardiogenic shock, and death, can occur. Intravenous lipid emulsion (ILE) therapy has been utilized for a multitude of poisonings with varying levels of success. Although a number of cases suggest the value of ILE therapy in cases of bupropion overdose, more recent data propose that its role may be overstated.Case ReportA young woman presented to the ED with altered mental status complicated by seizure after bupropion overdose. She subsequently developed cardiogenic shock requiring vasopressor support. Bedside echocardiogram revealed a decreased left ventricular ejection fraction (LVEF). She received ILE therapy with significant improvement in both hemodynamic status and LVEF by bedside ultrasound.Why Should an Emergency Physician Be Aware of This?Although the majority of patients presenting with bupropion overdose improve with supportive care, life-threatening sequelae are possible. ILE therapy has shown promise in a variety of different overdose situations, although the evidence in cases of bupropion poisoning has been varied, and it has traditionally been utilized as a last-line rescue modality. Based on hemodynamic parameters and bedside ultrasound, this case suggests that early initiation of ILE therapy should be considered in these cases, as the potential benefits likely outweigh the theoretical risks.     

Sporadic hereditary neuropathies misdiagnosed as chronic inflammatory demyelinating polyradiculoneuropathy: Pitfalls and red flags

Hereditary neuropathies may be misdiagnosed with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). A correct diagnosis is crucial for avoiding unnecessary therapies and access genetic counseling. We report on nine patients (seven men, mean age 49.2 ± 16.1) diagnosed with and treated as CIDP, in whom mutations or variants of unknown significance (VUS) in genes associated with hereditary neuropathies were reported. All underwent neurological and neurophysiological examination, eight also cerebrospinal fluid (CSF) analysis. In 4/9, nerve ultrasound and/or MR‐neurography were performed. All the patients complained of progressive upper or lower limbs sensory‐motor symptoms, with heterogeneous disease duration (1‐34 years, mean 8.6 ± 10.8). Neurophysiology showed demyelinating signs in seven patients, mixed findings with predominant axonal damage in two patients. Neuroimaging disclosed diffuse abnormalities at proximal and distal segments. Molecular screening showed PMP22 duplication in two patients, mutations in the MPZ, EGR2, and GJB1 genes were reported in each of the remaining patients. The two patients with mixed neurophysiological findings had p.Val30Met mutation in the transthyretin gene. Two patients had VUS in the MARS and HSPB1 genes. Four patients had partial response to immunomodulant therapies, and CSF and neurophysiological features suggesting an inflammatory condition concomitant with the hereditary neuropathy. Hereditary neuropathy may be misdiagnosed with CIDP. The most common pitfalls are CSF (high protein levels and oligoclonal bands), incorrect interpretation of neurophysiology, and transient benefit from therapies. Neuroimaging may be helpful in cases with atypical presentations or when severe axonal damage complicate the neurophysiological interpretation.     

Sonication of the anterior thalamus with MRI-Guided transcranial focused ultrasound (tFUS) alters pain thresholds in healthy adults: A double-blind,sham-controlled study

BackgroundTranscranial focused ultrasound (tFUS) is a noninvasive brain stimulation method that may modulate deep brain structures. This study investigates whether sonication of the right anterior thalamus would modulate thermal pain thresholds in healthy individuals.MethodsWe enrolled 19 healthy individuals in this three-visit, double-blind, sham-controlled, crossover trial. Participants first underwent a structural MRI scan used solely for tFUS targeting. They then attended two identical experimental tFUS visits (counterbalanced by condition) at least one week apart. Within the MRI scanner, participants received two, 10-min sessions of either active or sham tFUS spread 10 min apart targeting the right anterior thalamus [fundamental frequency: 650 kHz, Pulse repetition frequency: 10 Hz, Pulse Width: 5 ms, Duty Cycle: 5%, Sonication Duration: 30s, Inter-Sonication Interval: 30 s, Number of Sonications: 10, ISPTA.₀ 995 mW/cm2, ISPTA.₃ 719 mW/cm2, Peak rarefactional pressure 0.72 MPa]. The primary outcome measure was quantitative sensory thresholding (QST), measuring sensory, pain, and tolerance thresholds to a thermal stimulus applied to the left forearm before and after right anterior thalamic tFUS.ResultsThe right anterior thalamus was accurately sonicated in 17 of the 19 subjects. Thermal pain sensitivity was significantly attenuated after active tFUS. The pre-post x active-sham interaction was significant (F(1,245.95) = 4.03, p = .046). This interaction indicates that in the sham stimulation condition, thermal pain thresholds decreased 1.08 °C (SE = 0.28) pre-post session, but only decreased .51 °C (SE = 0.30) pre-post session in the active stimulation group.ConclusionsTwo 10-min sessions of anterior thalamic tFUS induces antinociceptive effects in healthy individuals. Future studies should optimize the parameter space, dose and duration of this effect which may lead to multi-session tFUS interventions for pain disorders.