Vagal control of the breathing pattern and respiratory mechanics in the adult and newborn rabbit

In an attempt to define the role of SARs on the breathing pattern and respiratory mechanics, we have studied adult rabbits anaesthetised, supine and tracheostomised during air breathing (A), after SO₂ breathing (200 ppm for a period long enough to abolish the apnea following lung inflation, 10–30 min) (S), and after bilateral vagotomy (V). Tidal volume and inspiratory time increased, while breathing frequency decreased from A to V. The effects of S depended upon the type of anaesthesia used, with a definite increase in volume and a drop in frequency in the urethane anaesthetized animals and a trend toward opposite changes with barbiturate anaesthesia. Total and lung compliance increased and total pulmonary resistance decreased from A to S; no further changes were observed with V. The combined changes in breathing pattern and mechanics decreased the respiratory work per minute from A to V, suggesting that the primary concern of the vagal afferent information is to regulation even with SO₂ concentration up to 330 ppm for 30 min. From A to V the changes in breathing pattern and compliance were similar to those observed in the adult.     

Cardiovascular patterns associated with threat and challenge appraisals: a within-subjects analysis

Previous studies demonstrated distinct cardiovascular patterns associated with threat and challenge appraisals for groups of participants. We extend these results by assessing whether appraisals continue to be associated with these cardiovascular response patterns within an individual as appraisals change. Participants completed four verbal mental arithmetic tasks for which they made appraisals before and after each task. Cardiac reactivity and total peripheral resistance (TPR) were calculated for the first and last minutes of each task, and the number of responses and percent correct were measured for each task. In line with our prediction, pretask appraisals were related to some task-related cardiac responses across the four tasks. In addition, task-related cardiovascular reactivity and behaviors both influenced appraisals following the task. Our findings suggest that an idiographic analysis of appraisals, cardiovascular physiology, and task-related behaviors provides a richer understanding of the appraisal process and reveals sex differences deserving further assessment.     

计算机辅助全膝置换中股骨力线定位精度的实验研究

摘要利用光学定位追踪仪确定全膝置换中患者的股骨头中心从而确定其股骨力线，在力线的定位精度分析中，首次采用股骨的三维重建模型进行精度校验。实验结果表明通过追踪固定于股骨末端的刚性定位器即能确定精确的股骨力线，与传统的髓内定位相比，不仅可重复性好，而且大大地提高了术中股骨力线的位置精度，将其位置偏差减小到10以内。     

The role of the splanchnic circulation in the regulation of total intravascular volume during alpha adrenergic receptor stimulation

Previous studies have not defined the contribution of the splanchnic circulation to the total intravascular volume change associated with selective alpha adrenergic receptor stimulation. Since the splanchnic circulation is responsible for the total volume changes associated with other types of selective autonomic receptor stimulation, the present study was undertaken to examine the influence of alpha adrenergic receptor stimulation on splanchnic intravascular volume, the hemodynamic mechanism responsible for the splanchnic volume change, and the contribution of the splanchnic volume change to the change in total volume. In 35 anesthetized dogs, blood from the vena cavae was drained into an extracorporeal reservoir and returned to the right atrium at a constant rate so that changes in total intravascular volume could be measured as reciprocal changes in reservoir volume. Phenylephrine infusion (100 g/min) for 20 min in 28 dogs was associated with a decrease in total volume of 64±17 (SEM) ml (P<0.0001). The response was abolished by either alpha adrenergic blockade or evisceration but was not attenuated by beta adrenergic blockade, sinoaortic baroreceptor denervation, ganglionic blockade, or splenectomy. In 5 animals with separate splanchnic perfusion and drainage, total and splanchnic volumes decreased 59±8 ml (P<0.0001) and 317±20 ml (P<0.0001), respectively, while transhepatic vascular resistance increased 17±4 cm H₂O·min/l (P<0.0001). These responses were abolished after alpha adrenergic blockade. Thus, splanchnic volume decreases with alpha adrenergic receptor stimulation, despite an increase in hepatic resistance to splanchnic, venous outflow. The splanchnic volume decrement is entirely responsible for the total volume decrement.The study was supported by NHLBI Grant 1 R23-HL27185, Grant 11-203-812 from the American Heart Association of Greater Hartford, Inc., and the Duberg Cardiovascular Research Fund. Dr. Rutlen was the Duberg Scholar in Cardiovascular Disease when the study was performed.This work was presented in part at the 1982 Scientific Sessions of the American Heart Association (Circ. 66:II-311)     

Delayed pressure urticaria

Delayed pressure urticaria (DPU) is a poorly understood syndrome. We describe 17 patients with DPU. Chronic urticaria was present in 94%. All had negative challenges for immediate demographism and cold urticaria. DPU was induced with a pressure challenge on the shoulder of 15 pounds for 15 min. Average onset of pressure lesions after challenge was 6.5. Lesions were painful, not pruritic, peaked at 9 hr, and disappeared by 24 to 48 hr. Fever, chills, and/or arthralgias occurred in 78%. Positive laboratory abnormalities included leukocytosis in 20% and elevated erythrocyte sedimentation rate in 37.5%. Skin biopsies of lesions showed perivascular round cell infiltrates and negative immunofluorescence. Urticaria responded to antihistamines, but not aspirin, in 100% of patients, while pressure lesions improved with nonsteroidal anti-inflammatory drugs (NSAID), but not antihistamines, in 80% of patients. Both urticaria and DPU were controlled with prednisone, which was necessary in 87.5% of patients. A severe nonremitting course was noted in 7%, 40% had a moderate remitting course requiring intermittent prednisone, and 53% had a mild remitting disease requiring no medication or antihistamines and/or NSAID only. We conclude that DPU is more common than previously appreciated and likely involves mediators other than histamine, possibly the prostaglandin system.     

全静脉营养液的合理应用

目的：探讨全静脉营养液的合理应用,以避免或减少并发症的发生;方法：查文献,从适应证、营养状况评定、组方、配制、药物的加入、输入、监测及及时过渡到肠内营养几个方面综述全静脉营养液的合理应用;结果：营养状况的准确评定、科学组方、合理配制、规范输入、准确监测、以及及早过渡到肠内营养,是全静脉营养液合理应用的重要环节;结论：全静脉营养液的合理应用,对避免或减少并发症的发生,成功地进行完全胃肠外营养有重要意义。     

全髋关节置换术后异位骨化及其预防

目的：探讨全髋关节置换术后异位骨化发生的原因、机制及其预防方法。方法：将139例接受全髋关节置换的患者入院时随机分为3组,A组53例,B组49例,C组37例,分别于术后次日口服维生素C（100mg,3/d)、消炎痛（25mg/3/d)和布洛芬（200mg,3/d),连续应用4周。术后3个月复查时行X线片检查。结果：异位骨化情况按Brooker分类,A组：0级24例,I级6例,Ⅱ级13例,Ⅲ级7例,Ⅳ级3例,异位骨化发生率54．7％（29／53）。B组：0级42例,Ⅰ级5例,Ⅱ级2例,发生率14．3％（7／49）。C组：0级32例,Ⅰ级3例,Ⅱ级、Ⅲ级各1例,发生率13．5％（5／37）。经统计学分析,异位骨化发生率A组与B组、A组与C组之间有显著差别（P＜0．01）,B组与C组之间无显著差别（P＞0．05）。结论：全髋关节置换术后发生异位骨化的原因很多,发生机制尚不清楚,非甾体类消炎镇痛类药物可有效地预防其发生。     

全髋置换术后脱位的原因和治疗

目的 探讨全髋关节置换术后脱位原因与治疗的关系。方法 对28例全髋置换术后脱位的病人,进行外展肌力检查和放射学测量。结果 17例侧卧外展试验阳性,8例单纯假体位置不当,11例单纯软组织不平衡,7例同时存在软组织不平衡和假体位置不当,2例假体位置正常性脱位。20例经闭合复位或一次再置换手术治疗取得成功,8例需一次以上手术治疗,5例软组织不平衡病例使用了限制性髋臼。结论 闭合复位是早期脱位的首选治疗方法,软组织不平衡的髋关节脱位,无论假体位置不当存在与否,常需多次手术治疗,手术中要考虑其机械稳定性（使用限制型髋臼假体）。     

Effect of Preoperative Modifiable Psychological and Behavioural Factors on Early Outcome Following Total Knee Arthroplasty in an Indian Population

BackgroundNon-surgical factors have been found to have significant impact on outcome following Total Knee Arthroplasty (TKA). The study was conducted to know the independent effect of each of the four interacting psychological factors: anxiety, depression, pain catastrophizing and kinesiophobia on early outcome following TKA in an Indian population.Materials and Methods104 consecutive patients undergoing TKA were included in the study and followed up at 6 weeks, 6 months and one year. Preoperatively, Hospital Anxiety and Depression Scale was used to diagnose and quantify anxiety and depression, pain catastrophizing and kinesiophobia were assessed using Pain Catastrophizing Scale and Tampa Scale for Kinesiophobia, respectively. Outcome was assessed on the basis of Knee Society Score and Knee Injury and Osteoarthritis Outcome Score. Regression analysis was done to know independent effect of each factor on outcome scores.ResultsNine (8.7%) patients were found to have undiagnosed psychopathology. The patients with psychopathologies were found to have significantly worse knee outcome scores on follow-up, although the rate of improvement in knee symptoms and function was not significantly different from those without psychopathology. The degree of Anxiety correlated with worse knee pain and stiffness up to 6 months while it correlated with poor knee function for a longer duration. The degree of depression and pain catastrophizing correlated with worse knee pain, stiffness and function at all visits while kinesiophobia didn’t show correlation independent other factors.ConclusionPsychopathology was found to be associated poor knee outcome scores with degree of preoperative depression and pain catastrophizing as significant independent predictors as poor outcome, whereas the effect of degree of anxiety on knee pain and stiffness was found to wane over time. Kinesiophobia didn’t show any independent correlation.Supplementary InformationThe online version of this article (10.1007/s43465-020-00325-x) contains supplementary material, which is available to authorized users.