Effect of propranolol on ventricular repolarization and refractoriness: Role of beta-blockade versus direct membrane effects

Summary The purpose of this study was to define the role of beta-adrenergic blockade and direct membrane effects in the ability of dl-propranolol to alter ventricular repolarization and refractoriness in the intact heart. The effective refractory period (ERP) and the local Q-T interval were measured at an epicardial site in the left ventricle in 14 open-chest dogs anesthetized with alpha-chloralose. Beta-adrenergic influences were eliminated in seven dogs (group 1) by stellate transection and nadolol (0.5 mg/kg IV), and enhanced in seven dogs (group 2) by stellate transection and stimulation of the left ansae subclavia. Each dog received an initial beta-blocking dose of propranolol (0.5 mg/kg) followed by a second, cumulative dose of 5.0 mg/kg. In group 1 dogs, there was no significant change in either the ERP or local Q-T interval in response to the first dose of propranolol. In group 2 dogs, left stellate stimulation significantly shortened the ERP (20±2 msec) and the local Q-T interval (17±4 msec). The first dose of propranolol prolonged these parameters to values not different from prestimulation control values. There was no change in the H-V interval, QRS complex duration, or diastolic threshold (DT) in either group after the initial propranolol dose. The second dose of propranolol significantly shortened the ERP (5±1 msec) and the local Q-T interval (11±2 msec) in both groups. This dose also significantly increased the DT, H-V interval, and QRS complex duration. In three additional nadolol-treated dogs, a single 5 mg/kg dose of propranolol shifted the entire strength-interval curve 4 to 7 msec earlier into electrical diastole. The data indicate that a beta-blocking dose of propranolol prolongs repolarization and refractoriness only when adrenergic input is elevated. In the absence of beta-adrenergic influences, high doses of propranolol shorten repolarization and refractoriness. This latter effect may be due to a direct membrane effect of the drug.     

老年妇科手术围手术期临床特点分析

目的探索老年妇科手术围手术期的临床特点。方法2001年1月至2004年3月老年妇女(年龄≥60岁)妇科手术病人50例为研究组,同期中年妇女(40～59岁)50例为对照组。监测麻醉前、达到完全阻滞平面时以及手术结束时病人的收缩压(SBP)、舒张压(DBP)、平均动脉压(MAP)、心率(HR)、血氧饱和度(SPO2)值,及术后最高体温、发热持续时间和其它并发症情况。结果两组病人达到完全阻滞平面时、手术结束时的SBP、DBP、MAP均较麻醉前显著降低(P<0.05),老年组下降幅度更大(P<0.001),而HR、SPO2及术后发热情况无明显差异。老年组术后并发症率16%,其中一例死于急性肺栓塞。中年组术后并发症率10%。结论老年妇女对妇科手术的耐受性较好,加强围手术期监护有助于提高手术的安全性。     

The effect of endocardial defibrillator shocks on basic atrial electrophysiology in man. Is post cardioversion atrial electrical 'remodelling' artefact?

AIMS: To determine the effect of an endocardial DC shock on the basic electrophysiology of the human atrium if delivered in sinus rhythm. METHODS AND RESULTS: A 5J endocardial R wave synchronized DC shock was delivered in 10 patients in stable sinus rhythm during ICD implantation for ventricular arrhythmias. There was no prior history of atrial fibrillation. Monophasic action potential duration (APD) and atrial effective refractory periods (AERP) were evaluated before, 1 min post DC shock, and 15 min post shock. These parameters were assessed at basic cycle lengths and at atrial paced cycle lengths of 600 ms and 400 ms at two right atrial sites; mid lateral right atrial wall (MRLA) and the right atrial appendage (RAA). There were no significant differences in APD 90, AERP or atrial refractory dispersion at any site or drive cycle length before, immediately after or 15 min after shock delivery. CONCLUSIONS: There are no significant changes in basic electrophysiological parameters following a DC shock delivered in sinus rhythm in patients with no prior history of atrial fibrillation. This suggests that atrial electrical remodelling occurs as a result of atrial fibrillation and is unrelated to shock artefact.     

TURP治疗198例高危前列腺增生症患者围术期的护理体会

目的：讨论经尿道前列腺电切术( TURP )治疗高危前列腺增生症( BPH )围术期的护理方法。方法对行TURP术治疗的198例高危BPH患者,给予充分术前准备、手术耐受力评估、控制手术时间。术后严密观察生命体征变化,积极防御水中毒等并发症。膀胱冲洗,及时处理膀胱经痉挛,以及出院后健康指导。结果198例患者均接受TURP术,术后排尿通畅,无严重并发症发生,痊愈出院。结论对行TURP术高危患者施以精心围手术期护理,可使患者平稳安全地度过围手术期,减少术后并发症,缩短患者住院时间,加快患者康复。     

探讨围手术期护理对腹腔镜子宫肌瘤切除患者的干预效果

目的：研究围手术期护理对腹腔镜子宫肌瘤切除患者的影响。方法将该院92例行腹腔镜治疗的子宫肌瘤切除患者以随机数表法分为观察组与对照组,两组均为46例,对照组采取常规护理,观察组采取术前、术中、术后围术期全程护理,比较两组临床指标变化情况、止痛剂使用及伤口愈合情况。结果观察组肛门排气时间、住院时间、手术时间、术中出血量分别为(7.67±1.85)h、(3.03±1.46)d、(66.64±12.03)min、(101.35±22.03)mL与对照组(11.03±2.48)h、(5.82±1.61)d、(72.38±11.98)min、(121.85±25.69)mL比较显著较低,对比差异有统计学意义(P<0.05);两组止痛剂使用率比较差异无统计学意义(P>0.05),不良反应发生率21.74%与对照组47.83%比较显著较低(P<0.05)。结论术前、术中、术后全程护理措施可缩短患者康复时间,促进伤口愈合,减少止痛剂使用率,具有较高的临床应用价值。     

优质护理在脑肿瘤患者围术期中的应用分析

目的：探讨优质护理在脑肿瘤患者围术期中的应用效果。方法选取我院收治的120例脑肿瘤手术患者作为研究对象,根据入院先后顺序分为干预组和对照者,各60例,对照组实施常规护理,干预组实施优质护理,观察两组患者的护理效果。结果干预后,两组患者的ADL评分均较干预前显著提高,且干预组干预后的ADL评分显著高于对照组(P<0.05);干预后,干预组的独立、轻度依赖者所占比例均显著高于对照组,中度依赖、重度依赖者所占比例均显著低于对照组(P<0.05);干预组术后并发症发生率为5.00%,显著低于对照组的31.67%,组间比较差异具有统计学意义(P<0.05)。结论对脑肿瘤手术患者实施优质护理,能有效提高围术期护理质量,改善患者的心理状态,提高患者的身心舒适度及生活质量,值得推广。     

围生期产妇健康素养量表条目筛选

目的：对围生期产妇健康素养量表条目池进行条目筛选,形成条目更可靠、更准确的围生期产妇健康素 养量表。方法：运用Delphi法,请14名妇幼专家对研究者自行编写的56个条目的需要性和重要性进行两轮函询,保 留50个条目。用该条目池对350名产后1~3 d的产妇进行横断面调查,选取其中10%的调查对象1周后重测。在这些数 据基础上,运用χ2检验法、相关系数法(2种)、因子分析法、Cronbach’s α系数法、重测信度法6种方法进行条目筛 选,保留3种或3种以上方法均不需删除的条目,组成最终量表。结果：重测结果Person相关系数为0.507(P=0.004)。 通过6种筛选方法删除的条目数量分别为：1)χ2检验法删除9条;2)相关系数法1删除25条;3)相关系数法2删除1条;4) Cronbach’s α系数法删除19条;5)因子分析法删除8条;6)重测信度法删除37条。最终由33个条目组成围生期产妇健 康素养量表。结论：运用6种条目筛选方法获得了精简后的量表,但距离推广应用还有很大距离,需要在人群中进行 大样本调查,进行信效度检验。     

清代后中国文学的历史定位

清代后中国文学的史学定位在现代文学内部划分为民国时期文学和共和国时期文学。与现代文学的意义概念不同的是,民国文学和共和国文学在中国现代文学的框架内都仅仅是一个时间概念。放弃文学史研究的整体主义努力,以多样主义或归纳主义的心态面对历史。中国现代文学的起点在1912年为各种争论的最大公约数,各种起点事件均看着是与起点联系的相关事件。先锋与常态的理论发现为一体两翼的成立找到理论依据。"民国机制"与"民国文学机制"的提出拓展了民国文学的研究思路,但本身却是可商之论。如果我们将民国文学机制改变为"民国文学环境"或者"民国文学生态",那么在民国时期不同时空中不同类型的文学自然会产生于不同的文学环境或生态。     

Clinical study of herbal mixture “Diding Oral Medicine” as an alternative to preventative antibiotics in perioperative hemorrhoids: A CARE-compliant article

To study the clinical effects of Diding Oral Medicine as an alternative to preventative antibiotics in perioperative hemorrhoids.From August 2017 to February 2018, a total of 214 patients who were treated with external exfoliation and internal ligation of mixed hemorrhoids in our hospital were divided into the control group and experimental group by way of stratified random (107 cases in each group). Patients in the control group were given antibiotics preventatively before operation, while patients in the experimental group took Diding Oral Medicine before operation, and the white blood cell count, neutrophil count, wound recovery, pain score, anal bulge score, and pathogen culture of wound secretions were compared between the 2 groups.There was no significant difference in white blood cell count and neutrophil count between both groups before and after operation (P > .05). The wound seepage score, wound edema score, and wound area score in the experimental group were lower than those in the control group, and the wound healing in the experimental group was shorter than that in the control group (all P < .05). The pain score and anal bulge score of the experimental group were decreased significantly compared to the control group (P < .05). In addition, the detection rate of pathogenic bacteria in the experimental group was downregulated significantly compared to the control group (P < .05).The Diding Oral Medicine has prominent bacteriostatic and antibacterial effects on patients with hemorrhoids during perioperative period, and promotes wound healing, reduces pain stress, and anal bulge.