High-Density Circumferential Pulmonary Vein Mapping with a 20-Pole Expandable Circular Mapping Catheter

The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation.     

A prospective analysis of 1400 pulmonary artery catheterizations in patients undergoing cardiac surgery

During 1983 and 1984, 1305 patients underwent 1,400 pulmonary artery (PA) catheterizations. Successful placement was achieved in 1397 (99.6%) of 1,403 attempts. The catheters were inserted via the right internal jugular vein on 1364 occasions. The median duration of monitoring was 28 h with a range from 3 to 220 h. Central venous puncture complications included carotid artery puncture in 67 instances (4.8%) and pneumothorax in one patient. Insertion of the catheters was associated with supraventricular arrhythmias on 11 occasions, ventricular arrhythmias on 930 (66.4%), right bundle branch block on two and a total heart block on one occasion. Eighteen (2.3%) of the 794 cultured catheter tips were positive. An in situ time of more than 72 h was associated with a significantly higher percentage (7.2%) of positive tip cultures compared with an in situ time of less than 72 h (P less than 0.01). Repeated PA catheterization was not associated with significantly more complications than the initial catheterization. The results show that monitoring with a PA catheter in cardiac surgical patients is associated with a low incidence of morbidity.     

低潮气量治疗在机械通气肺结核术后合并呼吸衰竭患者中的应用

目的 探讨低潮气量维持通气对肺结核术后合并呼吸衰竭患者的应用价值。方法 在有效的抗结核、抗感染治疗的基础上，对32例肺结核术后合并呼吸衰竭患者进行低潮气量（6～8ml／kg）机械通气治疗，观察疗效及并发症。结果 呼吸衰竭治愈31例，死亡1例，治愈率96．9％，无明显并发症。结论 低潮气量维持通气对肺结核术后合并呼吸衰竭患者的治疗是安全的，且疗效显著。     

Determination of serotonin and 5-hydroxyindoleacetic acid in guinea pig and human prostate using HPLC

The finding of significant numbers of endocrine-paracrine (EP) cells in the prostate glands of guinea pigs and man suggests that these cells may be important in the regulation or modulation of prostatic function. Serotonin is a biogenic amine common to most prostatic EP cells. In order to extend current knowledge relating to these cells, an assay was developed using high-performance liquid chromatography to quantitate serotonin and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in guinea pig and human prostatic tissue extracts. Levels of serotonin and 5-HIAA in the guinea pig whole-gland preparation were 105.4 +/- 70.6 ng/g and 48.4 +/- 95.7 ng/g, respectively. Normal human prostatic tissue contained 1423.9 +/- 750.8 ng/g serotonin and 66.7 +/- 92.8 ng/g 5-HIAA. Recoveries ranged between 60 and 100%. The detection limits were 24 pg/injection for serotonin and 12 pg/injection for 5-HIAA. This assay provides an expeditious, specific and highly sensitive method for the simultaneous determination of monoamines in guinea pig and human prostatic tissue.     

Curative Laparoscopic Resection for Pancreatic Neoplasms: A Critical Analysis from a Single Institution

Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis: group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients); group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients); and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R ₀ or R ₁ resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival. The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days. In this series, 27 patients (26.2%) had malignant disease. R ₀ resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant lesions of the pancreas.     

靶重建放大扫描对肺孤立性结节病变的诊断意义

目的：探讨靶重建放大扫描技术对肺孤立性结节病变的诊断价值。方法：对63例患者先行常规CT平扫，选定结节处为兴趣区，行薄层靶重建放大扫描，层厚、层距为2mm，FOV为160。结果：42例恶性病变中有37例表现为深分叶，占88．1％；21例良性病变中有15例表现为浅分叶，占71．4％。恶性结节中15例内部出现条状低密度支气管征；7例出现血管集中征；8例出现空泡征；病变内部出现液化坏死13例，其中恶性病变ll例。22例出现钙化，包括12例良性病变和10例恶性病变。2例错构瘤内均见小面积脂肪性低密度影。结论：靶重建放大扫描比普通CT扫描可提供更多的信息，对良恶性病变的鉴别诊断有一定价值。恶性病变大多数为深分叶，良性病变大多数为浅分叶或无分叶。     

Interobserver Agreement for the Diagnosis of Venous Thromboembolism on Computed Tomography Chest Angiography and Indirect Venography of the Lower Extremities in Emergency Department Patients

Objectives: To determine interobserver agreement between radiologists for computed tomography (CT) angiography and venography. CT venography of the lower extremities combined with standard CT angiography of the chest may result in an increased overall diagnosis rate of venous thromboembolism (pulmonary embolism or deep venous thrombosis).
Methods: The study had a retrospective cohort design. The population consisted of emergency department patients who were evaluated for suspected pulmonary embolism. A random sample of 50 patients diagnosed and treated for venous thromboembolism and 50 age- and gender-matched patients whose CT angiograms and venograms were read as negative were enrolled. The original reading (R1) was compared with readings of two study radiologists: R2, a general radiologist, and R3, a radiologist with fellowship training in cross-sectional imaging. All readers were blinded to each other.
Results: Both R2 and R3 found both CT angiogram and venogram components technically adequate in 95% (95% CI = 89% to 98%) and 86% (95% CI = 78% to 92%) of studies, respectively. The agreement was very good for CT angiography (lowest agreement = 92%; lowest κ = 0.83) and was good for CT venography (85%, κ = 0.65). In nine cases, R1 read the CT angiogram as negative but the venogram as positive for DVT, whereas both R2 and R3 read both components as negative in four of these nine, suggesting a false-positive isolated DVT rate of 44% (95% CI = 19% to 73%). In no case did R1 read both scan components as negative when R2 and R3 agreed on presence of pulmonary embolism or DVT.
Conclusions: Diagnosis of pulmonary embolism on CT angiography is more reliable than diagnosis of isolated DVT on CT venography.     

双光气致急性损伤对兔肺泡Ⅱ型细胞形态学的影响

目的：通过对日本大耳兔双光气肺损伤后肺泡Ⅱ型细胞内磷脂和形态学变化的观察，探讨双光气对肺Ⅱ型细胞的损伤及其机制．方法：将纯种日本大耳白兔35只随机分为对照组(n＝10)、染毒即刻组(n＝5)、染毒2h组(n＝5)染毒4h组(n＝5)、染毒8h组(n＝5)、染毒12h组(n＝5)；采用浓度一时间法动态式染毒，染毒后按不同时间点对实验动物进行颈总动脉插管放血处死，取肺并用肺灌洗液对支气管肺泡进行灌洗，然后取肺组织作冰冻切片，进行电镜观察，并测定细胞内磷脂含量．结果：肺Ⅱ型细胞内磷脂含量在染毒即刻开始时较正常组含量下降(P＜0．01)；在染毒2h时降到最低，之后上升(P＜0．05)，而在4h后又下降(P＜0．05)．染毒终止后，损伤逐渐加重，染毒后2h磷脂因消耗而降低．染毒后4h，由于代偿功能启动，磷脂短暂升高，出现致伤性代偿期．从染毒2h后开始，细胞损伤加重，磷脂合成进入失代偿期，合成逐渐减少．到染毒后8h，肺泡Ⅱ型细胞内细胞处于致伤性和致死性细胞改变的临界点，细胞出现致死性改变，磷脂合成、分泌停止，细胞出现死亡．结论：兔在双光气染毒12h内，肺泡表面活性物质磷脂的改变有差异，随细胞损伤程度发生改变，出现明显中毒分期：即致伤性改变期、致伤性代偿期、致伤性失代偿期、致死性改变期．     

PULMONARY BLOOD DISTRIBUTION AFTER TOTAL CAVOPULMONARY CONNECTION OF DIFFERENT TYPES

Objective. To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection (TCPC) of different types, and to provide the selection of the best type .Methods. Thirty-two consecutive survival patients after TCPC underwent radionuclide lung perfusion imaging. According to the radionuclide counts in the left and right lungs, analyses of the distribution of blood flow from superior venous cava (SVC) and inferior venous cava (IVC) and the whole pulmonary blood flow in both lungs were made. All patients were divided into 4 groups by the the anastomosis between IVC and pulmonary artery.Results. Group Ⅰ: The flow ratio of the IVC to left lung was greater than that to the right lung , P≤0. 01; the flow ratio of the SVC to right lung was greater than that to the left lung, P≤0. 01; and the whole pulmonary blood flow went dominantly to the left lung, P≤0. 05, which is not in line with physiological distribution. Group Ⅱ: the flows from the SVC and IVC were mixed in the middle of     

National Study of Emergency Department Visits for Acute Exacerbation of Chronic Obstructive Pulmonary Disease, 1993–2005

Objectives: Little is known about recent trends in U.S. emergency department (ED) visits for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or about ED management of AECOPD. This study aimed to describe the epidemiology of ED visits for AECOPD and to evaluate concordance with guideline‐recommended care. Methods: Data were obtained from National Hospital Ambulatory Medical Care Survey (NHAMCS). ED visits for AECOPD, during 1993 to 2005, were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. Concordance with guideline recommendations was evaluated using process measures. Results: Over the 13‐year study period, there was an average annual 0.6 million ED visits for AECOPD, and the visit rates for AECOPD were consistently high (3.2 per 1,000 U.S. population; P_trend = 0.13). The trends in the use of chest radiograph, pulse oximetry, or bronchodilator remained stable (all P_trend > 0.5). By contrast, the use of systemic corticosteroids increased from 29% in 1993–1994 to 60% in 2005, antibiotics increased from 14% to 42%, and methylxanthines decreased from 15% to <1% (all P_trend < 0.001). Multivariable analysis showed patients in the South (vs. the Northeast) were less likely to receive systemic corticosteroids (odds ratio [OR] = 0.6; 95% confidence interval [CI] = 0.4 to 0.9). Conclusions: The high burden of ED visits for AECOPD persisted. Overall concordance with guideline‐recommended care for AECOPD was moderate, and some emergency treatments had improved over time.