BACKGROUND & AIMS: Rupture of atheromatous plaques leading to acute coronary syndromes usually occur in lipid-reach and well-developed coronary lesions. We describe 2 unusual patients with acute coronary syndromes in whom there was angiographic and intravascular ultrasound evidence of an intraluminal thrombus overlying a small, nonocclusive plaque in an enlarged coronary artery.

背景与目标： 导致急性冠状动脉综合征的动脉粥样硬化斑块破裂通常发生在脂质到达和发达的冠状动脉病变中。我们描述了2例不寻常的急性冠状动脉综合征患者，其中有血管造影和血管内超声证据表明腔内血栓覆盖了扩大的冠状动脉中的一个小的非闭塞斑块。

BACKGROUND & AIMS: BACKGROUND:Although the benefit of thrombolytic therapy in reducing mortality in acute myocardial infarction is well established, the types of bleeding and risk factors for bleeding are less well described in large trials.

METHODS AND RESULTS:We analyzed the baseline characteristics, outcomes, and incidence of bleeding by location, severity, and treatment assignment among 41,021 patients in the GUSTO-I trial of thrombolysis for acute myocardial infarction. Of the 40,903 patients for whom there were complete data, 1.2% suffered severe bleeding and 11.4% experienced moderate hemorrhage at a variety of sites. The most common sources of bleeding were procedure related. The thrombolytic regimen was strongly related to the incidence of bleeding; comparatively more bleeding was seen with the therapies of streptokinase plus intravenous heparin and the streptokinase and tissue plasminogen activator plus intravenous heparin combination. In multivariate analysis, the four most powerful independent predictors of hemorrhage were older age, lighter body weight, female sex, and African ancestry; they remained the most important predictors of bleeding when multivariate analysis was performed on patients who did not undergo invasive procedures. The presence of serious hemorrhage was associated with other undesirable outcomes (recurrent events, left ventricular dysfunction, arrhythmia, or stroke).

CONCLUSIONS:Important predictors of bleeding in this population are increased age, lighter weight, female sex, African ancestry, and experiencing invasive procedures. Other nonhemorrhagic adverse clinical outcomes were associated with moderate and severe bleeding, which was in turn associated with increased length of hospital stay and mortality at 30 days.

背景与目标： 背景 : 尽管溶栓治疗在降低急性心肌梗死死亡率方面的益处已得到充分证实，但在大型试验中，出血类型和出血危险因素的描述较少。
方法和结果 : 在GUSTO-I急性心肌梗死溶栓试验中，我们分析了41,021名患者的基线特征，结局和出血发生率，按位置，严重程度和治疗分配。在40,903例有完整数据的患者中，1.2% 例严重出血，11.4% 例在不同部位出现中度出血。最常见的出血来源与手术有关。溶栓方案与出血发生率密切相关; 链激酶加静脉肝素以及链激酶和组织型纤溶酶原激活剂加静脉肝素联合治疗的出血相对较多。在多变量分析中，出血的四个最有效的独立预测因子是年龄较大，体重较轻，女性和非洲血统; 当对未接受侵入性操作的患者进行多变量分析时，它们仍然是出血的最重要预测因子。严重出血的存在与其他不良结果 (复发事件，左心室功能障碍，心律失常或中风) 相关。
结论 : 该人群出血的重要预测因素是年龄增加，体重减轻，女性，非洲血统，经历侵入性手术。其他非出血性不良临床结局与中度和重度出血相关，而中度和重度出血又与30天时的住院时间和死亡率增加相关。

BACKGROUND & AIMS: BACKGROUND:In early-stage lung cancer, evidence is accumulating for the benefits of lobectomy by video-assisted thoracic surgery (VATS) over open lobectomy. Few thoracic training programs offer sufficient experience in this technically demanding procedure. This article describes the evolution of a new graduate's practice from open thoracotomy to VATS lobectomy. STUDY DESIGN:Our model involves a transition in technique from posterolateral thoracotomy to muscle-sparing thoracotomy and, ultimately, to VATS lobectomy. This approach was evaluated by examining outcomes of open thoracotomy patients before VATS lobectomy and outcomes of the initial 30 VATS patients. Data were collected prospectively. RESULTS:Before undertaking VATS lobectomy, 94 major pulmonary resections were performed by thoracotomy. Mortality was 1.2% for lobectomy and 0% for pneumonectomy. Use of the muscle-sparing thoracotomy increased from 17% of patients in the first half to 70% in the latter half of this group. For the first 30 VATS lobectomy patients, the mean operative time was 168 minutes. Median blood loss was 200 mL. Conversion rate to open thoracotomy was 13.3%. Mortality was 3.3% and morbidity was 26.7%. After short-term followup (mean followup 16 months), overall survival for stage I lung cancer was 96%. CONCLUSIONS:With our approach, new graduates of thoracic surgery programs can safely transition to VATS lobectomy. Gaining experience with the lateral muscle-sparing thoracotomy is an important step in the transition, as it offers similar operative exposure. Longterm disease-free and overall survival data are needed to evaluate our oncologic efficacy with this approach.

背景与目标：

BACKGROUND & AIMS: Visual optics is taking on new clinical significance. Given that current refractive procedures can and do induce large amounts of higher order ocular aberration that often affects the patient's daily visual function and quality of life, we can no longer relegate the considerations of ocular aberrations to academic discussions. Instead, we need to move toward minimizing (not increasing) the eye's aberrations at the same time we are correcting the eye's spherical and cylindrical refractive error. These are exciting times in refractive surgery, which need to be tempered by the fact that after all the research, clinical, and marketing dust settles, the level to which we improve the quality of the retinal image will be guided by the trade-off between cost and the improvement in the quality of life that refractive surgery offers.

背景与目标： 视觉光学具有新的临床意义。鉴于当前的屈光手术可以并且确实会引起大量的高阶眼像差，这些像差通常会影响患者的日常视觉功能和生活质量，因此我们不能再将眼像差的考虑因素置于学术讨论中。相反，我们需要在校正眼睛的球形和圆柱形屈光不正的同时，朝着最小化 (不增加) 眼睛的像差的方向发展。在屈光手术中，这是激动人心的时刻，需要通过以下事实来缓解: 在所有研究，临床和营销尘埃落定之后，我们提高视网膜图像质量的水平将取决于成本与屈光手术提供的生活质量之间的权衡。

BACKGROUND & AIMS: OBJECTIVE:To assess the prevalence of night eating syndrome (NES) and binge eating disorder (BED) and their related behavioral and psychological correlates in persons who sought bariatric surgery. RESEARCH METHODS AND PROCEDURES:A consecutive series of 215 persons with extreme obesity (82% women, 70% European American) completed the Weight and Lifestyle Inventory and a semistructured interview as part of a pre-surgery behavioral/psychological assessment. Diagnoses for NES and BED were based on graded diagnostic criteria. RESULTS:Percentages of participants who met diagnostic criteria for NES by interview were 1.9% for the strictest definition and 8.9% across all definitions of NES. After interview, full DSM-TR criteria for BED were met by 4.2%; an additional 1.4% reported binge eating at least once per week. Self-reported prevalence of NES and BED were higher. Those with NES or BED had significantly more symptoms of depression and a greater history of psychological complications than the remaining sample. DISCUSSION:The prevalence rates of NES and BED among this population of bariatric surgery candidates were lower than expected based on previous reports. Findings and hypotheses regarding lowered prevalence rates are discussed.

背景与目标：

BACKGROUND & AIMS: BACKGROUND:The literature reports that the learning curve for laparoscopic Roux-en-Y gastric bypass (LRYGBP) is approximately 75-100 cases. This aim of the present study was to evaluate the safety and feasibility of shortening the learning curve for performing LRYGBP by an experienced laparoscopic surgeon. METHODS:This study analyzed retrospectively the first 100 consecutive LRYGBP cases performed by an experienced laparoscopic surgeon between April 2003 and September 2003. The surgeon performed these cases after first assisting in 30 cases, and the first 4 cases were proctored by an experienced laparoscopic bariatric surgeon. Two cases done after previous gastric stapling and Nissen fundoplication were excluded from the study. Outcome variables included operative time, complications, conversion, and mortality. RESULTS:For the first 100 LRYGBP patients, the mean age was 42.6 years (range, 22-62 years) and mean body mass index (BMI) was 47.6 kg/m2 (range, 36-71.8). The complications included 1 case of intestinal leak, 1 case of small bowel obstruction, 6 cases of gastrojejunal stenosis, 8 cases of wound infection, 1 case of wound seroma, and 2 cases of pulmonary embolism, resulting in 1 mortality. One case was converted to an open technique. Over the second 50 cases, there was a significant reduction in mean operative time, to 73 minutes (range, 39-145 minutes) from 113 minutes (range, 54-238 minutes) (P < .0001). However, despite the reduction in complication frequency (no gastrointestinal leak or obstruction, 2 cases of gastrojejunal stenosis, 2 cases of wound infection, no pulmonary embolism/deep venous thrombosis, and no mortality), there was no significant correlation between the mortality, conversion, and complication rates and the surgeon's experience. CONCLUSION:A bariatric surgical practice incorporating LRYGBP can be safely done by an experienced laparoscopic surgeon. With appropriate advanced laparoscopic skills, preparatory steps, proctorship, and adequate volume of cases, the learning curve for performing LRYGBP can be reduced to 50 cases. Further experience is associated with a significant reduction in operative time with acceptable mortality, complication, and conversion rates.

背景与目标：

BACKGROUND & AIMS: :Fine needle aspiration cytology (FNAC) is an important tool in the investigation of thyroid nodules and has few reported complications. We present the first report of recurrent laryngeal nerve palsy arising as a complication of thyroid nodule FNAC. This complication led to inaccurate diagnosis and unnecessarily radical surgery, with consequent increased morbidity.

背景与目标： : 细针穿刺细胞学检查 (FNAC) 是检查甲状腺结节的重要工具，几乎没有并发症的报道。我们提出了作为甲状腺结节FNAC并发症引起的喉返神经麻痹的第一份报告。这种并发症导致不准确的诊断和不必要的根治性手术，从而增加了发病率。

BACKGROUND & AIMS: PURPOSE:Medication and nutrient administration considerations after bariatric surgery are discussed. SUMMARY:Bariatric surgery is categorized by surgical technique (i.e., restrictive procedure or a combination of restrictive and malabsorptive procedures). Roux-en-Y gastric bypass is the most frequently performed bariatric surgery in the United States. Patients who have undergone this surgery are at risk for nutrient deficiencies. Several factors, such as pH and absorption sites, should be considered when providing these patients with appropriate supplementation. Drug solubility and surface area for absorption are also affected by gastric bypass procedures. By bypassing major portions of the small intestine, Roux-en-Y procedures drastically reduce the surface area for absorption. These changes may warrant manipulation in drug route or dose to ensure adequate delivery. Drugs with long absorptive phases that remain in the intestine for extended periods are likely to exhibit decreased bioavailability in these patients. The reduced size of the stomach after surgery can place patients at risk for adverse events associated with some medications. Medications implicated in such adverse events include nonsteroidal antiinflammatory drugs, salicylates, and oral bisphosphonates. Drugs that are rapidly and primarily absorbed in the stomach or duodenum are likely to exhibit decreased absorption in patients who have had combination restrictive-malabsorptive procedures. Because reduced drug absorption may result in decreased efficacy rather than toxicity, increased patient monitoring for therapeutic effects can help detect potential absorption problems. CONCLUSION:Selection of appropriate nutrient salts can improve nutrient replacement in patients who have undergone bariatric surgery. Changes in dosage forms based on drug characteristics can improve bioavailability.

背景与目标：

BACKGROUND & AIMS: :The practice of duplicate publication has been condemned widely in the scientific community and several studies have been conducted to establish the level of the problem in various surgical fields. A retrospective review of original articles from the British Journal of Plastic Surgery and Plastic and Reconstructive Surgery during 2000 was conducted, using Medline (PubMed). A total of 431 abstracts were screened, from which 27 index articles related to 33 'suspected redundant' publications. Further evaluation was carried out by comparing the full text versions of these articles and assigning a grade of non-dual, dual, potentially dual and 'salami-slicing'. Only four suspect articles were confirmed as having some degree of redundancy, and these related to three index articles (3/431, <1%). The incidence of duplication in plastic surgery literature seems to be much lower compared to other surgical specialties, providing reassurance for reviewers, editors and readers of these journals.

背景与目标： : 重复出版的做法在科学界受到广泛谴责，并且已经进行了几项研究以确定各个外科领域的问题水平。使用Medline (PubMed) 对《英国整形外科杂志》和《整形与重建外科2000年》的原始文章进行了回顾性审查。总共筛选了431篇摘要，其中27篇索引文章与33篇 “可疑冗余” 出版物有关。通过比较这些文章的全文版本并分配非对偶，对偶，潜在对偶和 “萨拉米切片” 等级来进行进一步评估。仅四个可疑文章被确认为具有一定程度的冗余，并且这些与三个索引文章有关 (3/431，<1%)。与其他外科专业相比，整形外科文献中重复的发生率似乎要低得多，这为这些期刊的审阅者，编辑和读者提供了保证。

BACKGROUND & AIMS: OBJECTIVES:This prospective study was designed to assess the sensitivity and specificity of Doppler ultrasound parameters in the diagnosis of cirrhosis and portal hypertension. METHODS:Portal and hepatic arterial Doppler ultrasound was performed on 76 patients with cirrhosis and esophageal varices and on 73 age- and sex-matched controls. The parameters evaluated were portal venous velocity and hepatic arterial pulsatility index. The liver vascular index was calculated as the ratio of portal venous velocity to hepatic arterial pulsatility index. RESULTS:Portal venous velocity was significantly lower (11.0 +/- 2.4 vs 15.9 +/- 2.8 cm/s, p < 0.001) and hepatic arterial pulsatility index was significantly higher (1.28 +/- 0.18 vs 0.95 +/- 0.17,p < 0.001) in patients than in controls. Thus, the liver vascular index was significantly lower in patients than in controls (8.7 +/- 2.1 vs 17.2 +/- 4.3 cm/s, p < 0.001). The sensitivity and specificity of these parameters in the detection of cirrhosis and portal hypertension was then analyzed with the receiver operating characteristic curve. The best cut-off values were considered to be 13 cm/se of portal venous velocity and 1.1 of hepatic arterial pulsatility index, showing a sensitivity and specificity of 83, 85, 84, and 81%, respectively. The best cut-off value of the liver vascular index was 12 cm/s with a sensitivity and specificity of 97 and 93%, respectively. CONCLUSIONS:The liver vascular index is a high sensitive and specific Doppler ultrasound parameter in the diagnosis of cirrhosis and portal hypertension.

背景与目标：

BACKGROUND & AIMS: BACKGROUND AND PURPOSE:Scleroderma is an immune-mediated disease characterized by excess deposition of collagen leading to microvascular occlusion. Morbidity and mortality are often secondary to pulmonary hypertension from injury to pulmonary microvasculature and interstitial lung disease. This study correlated P-wave findings on the 12-lead electrocardiogram (ECG) with mean pulmonary artery pressure (mPAP) measured by right heart catheterization in patients with scleroderma. METHODS:A retrospective review of 12-lead ECGs in 23 patients referred to a rheumatology clinic with the diagnosis of scleroderma was performed. Right heart catheterization was performed within 1 month of the resting ECG. RESULTS:Linear regression related P-wave amplitude in lead II with mPAP (r = 0.52, P = .011) This model was 73% sensitive and 67% specific for the presence or absence of elevated mPAP. CONCLUSIONS:P-wave amplitude analysis on the ECG may be helpful in the assessment of pulmonary hypertension in patients with scleroderma.

背景与目标：

BACKGROUND & AIMS: The expression and localization of hepatocyte growth factor/scatter factor (HGF/SF) were examined immunohistochemically in 59 human coronary artery lesions retrieved by directional coronary atherectomy and compared with the localization of transforming growth factor beta isoforms (TGF-beta 1, -beta 2, and -beta 3). In 21 of the 59 specimens (35.6%) HGF-like immunoreactivity (HGF-IR) was revealed. The HGF immunopositivity rate of 45% (14/31) in thrombotic tissue was significantly (P < 0.05) higher than the rates of 7.3% (4/55), 7.1% (3/42), and 0% (0/14) in fibrous tissue, neointimal hyperplasia and atheromatous gruel, respectively. Immunoreactivity for HGF was much weaker than that for TGF-beta isoforms in these components except in thrombotic tissue. These cells exhibiting strong HGF-IR were inflammatory cells such as monocytes/macrophages in thrombotic tissue, in tissue lesions adjacent to a thrombus, and outside the capillary walls in a portion of the neovascularized lesions. Smooth muscle cells (SMCs) hardly demonstrated HGF-IR. In contrast, in control coronary arteries obtained at autopsy, the HGF-IR was strongly expressed in SMCs. These findings suggest that HGF produced by macrophages play a part in the process of coronary plaque formation attributable to thrombus in man.

背景与目标： 通过免疫组织化学检查了通过定向冠状动脉粥样斑块切除术检索的59例人冠状动脉病变中肝细胞生长因子/散射因子 (HGF/SF) 的表达和定位，并将其与转化生长因子 β 亚型 (tgf-β1，-β2和-β3) 的定位进行了比较。在59个标本中的21个 (35.6%) 中，HGF样免疫反应性 (hgf-ir) 被揭示。血栓组织中45% (14/31) 的HGF免疫阳性率显着 (P < 0.05) 高于纤维组织，新内膜增生和动脉粥样硬化稀粥中的7.3% (4/55)，7.1% (3/42) 和0% (0/14)。分别。除血栓形成组织外，这些成分中HGF的免疫反应性比TGF-β 同工型的免疫反应性弱得多。这些表现出强hgf-ir的细胞是炎性细胞，例如血栓形成组织中，与血栓相邻的组织病变以及部分新生血管病变的毛细血管壁外部的单核细胞/巨噬细胞。平滑肌细胞 (smc) 几乎不显示HGF-IR。相反，在尸检获得的对照冠状动脉中，hgf-ir在smc中强烈表达。这些发现表明，巨噬细胞产生的HGF在人类血栓形成引起的冠状动脉斑块形成过程中发挥了作用。

BACKGROUND & AIMS: UNLABELLED:A Methodical Study:

AIM OF THE STUDY:To analyse the feasibility of colour and spectral Doppler assessment of blood flow in the fetal right (RPA) and left (LPA) main pulmonary arteries in relation to fetal position and to gestational age.

STUDY DESIGN:The fetal position was a priori divided into 3 types, depending on whether the fetal heart was visualised apically (Type 1), from the right side (Type 2) or from the left side (Type 3). Three groups A (19-25 weeks gestation), B (26-32) and C (33-39) including 33 consecutive pregnancies each, were examined to document the fetal position as well as the rate of the successful Doppler examinations of the RPA and/or LPA.

RESULTS:The fetal position Type 2 was most common throughout gestation (in group A = 42%, B = 36%, C = 51%) followed by the type 3 and then type 1. The rate of successful Doppler records from the RPA and LPA depended on the fetal position: In Type 2 RPA in 98%; in Type 3, LPA in 100%; but the apical approach was not effective (< 40%). Depending on gestational age, the success rates for a Doppler examination of at least one vessel were high (> 85%), whereas successful examination of both vessels was unlikely (12%).

CONCLUSIONS:In the second half of pregnancy, independent of fetal position, Doppler examination of at least one pulmonary artery is successful in most cases, whereas the assessment of both vessels is rather difficult.

背景与目标： 未标记 : 有条不紊的研究:
研究的目的 : 分析彩色和频谱多普勒评估胎儿右 (RPA) 和左 (LPA) 主肺动脉血流与胎儿位置和胎龄的可行性。
研究设计 : 根据胎儿心脏是从右侧 (2型) 还是从左侧 (3型) 可视化，先验地将胎儿位置分为3种类型。A组 (妊娠19-25周)，B组 (26-32) 和C组 (33-39)，每组33次连续怀孕，检查以记录胎儿位置以及RPA和/或LPA的成功多普勒检查率。
结果 : 2型胎儿位置在整个妊娠期间最常见 (A组 = 42%，B = 36%，C = 51%) 接着是类型3，然后是类型1。来自RPA和LPA的成功多普勒记录的速率取决于胎儿位置: 在2型RPA中98%; 在3型中，在100% 中LPA; 但是根尖方法无效 (< 40%)。根据胎龄的不同，对至少一个血管进行多普勒检查的成功率很高 (> 85%)，而对两个血管的成功检查不太可能 (12%)。
结论 : 在怀孕的后半段，在大多数情况下，独立于胎儿位置，对至少一条肺动脉进行多普勒检查是成功的，而对两条血管的评估相当困难。

BACKGROUND & AIMS: Epoxyeicosatrienoic acids (EETs) are endothelium-derived arachidonic acid metabolites of cytochrome P450. They dilate coronary arteries, open K+ channels, and hyperpolarize vascular smooth muscles. However, the mechanisms of these smooth muscle actions remain unknown. This study examined the effects of EETs on the large-conductance Ca(2+)-activated K+ channel (KCa) in smooth muscle cells of small bovine coronary arteries. In cell-attached patch-clamp experiments, 11,12-EET produced a 0.5- to 10-fold increase in the activity of the KCa channels when added in concentrations of 1, 10, and 100 nmol/L. In the inside-out excised membrane patch mode, 11,12-EET was without effect on the activity of the KCa channel unless GTP (0.5 mmol/L) or GTP and ATP (1 mmol/L) were added to the bath solution. In the presence of GTP and ATP, the increase in the KCa channel activity with 11,12-EET in inside-out patches was comparable to that in cell-attached patches. This effect of 11,12-EET in inside-out patches was blocked by the addition of GDP-beta-S (100 mumol/L). In outside-out patches, 11,12-EET also increased the KCa channel activity when GTP and ATP were added to the pipette solution. The addition of a specific anti-Gs alpha antibody (100 nmol/L) in the pipette solution completely blocked the activation of the KCa channels induced by 11,12-EET. An anti-G beta gamma or anti-Gi alpha antibody was without effect. We conclude that 11,12-EET activates the KCa channels by a Gs alpha-mediated mechanism. This mechanism contributes to the effects of EETs as endothelium-derived hyperpolarizing factors to hyperpolarize and relax arterial smooth muscle.

背景与目标： 环氧二十碳三烯酸 (EETs) 是细胞色素p450的内皮衍生的花生四烯酸代谢产物。它们扩张冠状动脉，打开K通道，并使血管平滑肌超极化。然而，这些平滑肌作用的机制仍然未知。这项研究检查了EETs对小冠状动脉平滑肌细胞中大电导Ca(2) 激活的K通道 (KCa) 的影响。在细胞附着的膜片钳实验中，当以1、10和100 nmol/L的浓度添加时，11,12-eet使KCa通道的活性增加了0.5至10倍。在由内向外切除的膜贴片模式中，11,12-eet对KCa通道的活性没有影响，除非将GTP (0.5 mmol/L) 或GTP和ATP (1 mmol/L) 添加到浴液中。在存在GTP和ATP的情况下，由内而外的贴片中11,12-eet的KCa通道活性增加与细胞附着的贴片相当。由内而外的贴片中11,12-eet的这种作用被添加GDP-β-S (100 mumol/L) 所阻断。在向外贴剂中，当将GTP和ATP添加到移液器溶液中时，11,12-eet也会增加KCa通道活性。在移液器溶液中添加特异性抗Gs α 抗体 (100 nmol/L) 完全阻断了由11,12-eet诱导的KCa通道的激活。抗G β γ 或抗Gi α 抗体无效。我们得出的结论是，11,12-eet通过Gs α 介导的机制激活了KCa通道。该机制有助于EETs作为内皮衍生的超极化因子，使动脉平滑肌超极化和松弛。

BACKGROUND & AIMS: BACKGROUND:Several case reports have raised serious concerns about the safety of shoulder surgery in the beach-chair position, related to global cerebral hypoperfusion. We summarize our experiences with 15,014 cases of shoulder arthroscopy over an 11-year period. Our primary aim was to evaluate the incidence of intraoperative or immediate postoperative neurologic events and secondarily to relate other perioperative complications. METHODS:We searched our online deidentified departmental quality improvement and patient safety database for adverse outcomes associated with arthroscopic shoulder surgery performed in the beach-chair position for the 11-year period between April 2001 and November 2011, as well as our hospital-system database and a statewide database. This was compared with the total number of such cases, available from our department billing database. RESULTS:The total rate of adverse events was 0.37%. Neurologic abnormalities suggestive of acute cerebral ischemia or hemorrhage did not occur in the immediate perioperative period. One new neurologic deficit was reported, secondary to ischemic stroke, which occurred 24 hours after the surgery. The most frequent complications detected were unplanned return to care (0.067%), local anesthetic systemic toxicity (0.053%), and airway compromise requiring unplanned intubation (0.033%). Complications were infrequent and did not vary in incidence over the course of the study. CONCLUSIONS:This retrospective study suggests that intraoperative or immediate postoperative stroke is rare when surgery is conducted in beach-chair position in conjunction with regional anesthesia, propofol sedation, and spontaneous respiration via natural airway.

背景与目标：