Mechanisms underlying the sensation of dyspnea

Dyspnea is defined as a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity. It is a common symptom among patients with respiratory diseases that reduces daily activities, induces deconditioning, and is self-perpetuating. Although clinical interventions are needed to reduce dyspnea, its underlying mechanism is poorly understood depending on the intertwined peripheral and central neural mechanisms as well as emotional factors. Nonetheless, experimental and clinical observations suggest that dyspnea results from dissociation or a mismatch between the intended respiratory motor output set caused by the respiratory neuronal network in the lower brainstem and the ventilatory output accomplished. The brain regions responsible for detecting the mismatch between the two are not established. The mechanism underlying the transmission of neural signals for dyspnea to higher sensory brain centers is not known. Further, information from central and peripheral chemoreceptors that control the milieu of body fluids is summated at higher brain centers, which modify dyspneic sensations. The mental status also affects the sensitivity to and the threshold of dyspnea perception. The currently used methods for relieving dyspnea are not necessarily fully effective. The search for more effective therapy requires further insights into the pathophysiology of dyspnea.     

Synthesis and Characterization of Mechanical Properties and Wire Cut EDM Process Parameters Analysis in AZ61 Magnesium Alloy + B4C + SiC

Wire Cut Electric Discharge Machining (WCEDM) is a novel method for machining different materials with application of electrical energy by the movement of wire electrode. For this work, an AZ61 magnesium alloy with reinforcement of boron carbide and silicon carbide in different percentage levels was used and a plate was formed through stir casting technique. The process parameters of the stir casting process are namely reinforcement %, stirring speed, time of stirring, and process temperature. The specimens were removed from the casted AZ61 magnesium alloy composites through the Wire Cut Electric Discharge Machining (WCEDM) process, the material removal rate and surface roughness vales were carried out creatively. L 16 orthogonal array (OA) was used for this work to find the material removal rate (MRR) and surface roughness. The process parameters of WCEDM are pulse on time (105, 110, 115 and 120 µs), pulse off time (40, 50, 60 and 70 µs), wire feed rate (2, 4, 6 and 8 m/min), and current (3, 6, 9 and 12 Amps). Further, this study aimed to estimate the maximum ultimate tensile strength and micro hardness of the reinforced composites using the Taguchi route.     

Timely discharge of low-risk STEMI patients admitted for primary PCI in an Essex cardiothoracic centre

Data for low-risk ST-elevation myocardial infarction (STEMI) patients in the Essex cardiothoracic centre (CTC) during a three-month period were evaluated and the average duration of admission was calculated to be 67.2 hours. The data were sifted by applying Second Primary Angioplasty in Myocardial Infarction (PAMIII) criteria for low-risk STEMI patients who could be safely discharged after 48 hours. After application of a proforma as a quality improvement intervention tool, data were re-assessed and the average time of admission observed for a similar cohort of patients dropped down to an average of 55.2 hours. Overall, there was a 13% average increase in rate of early discharge for low-risk STEMI patients.     

Informal caregiver strain,preference and satisfaction in hospital-at-home and usual hospital care for COPD exacerbations: Results of a randomised controlled trial

Background

Informal caregivers play an important role in hospital-at-home schemes. However they may increase their burden, especially chronic diseases, like COPD. In the absence of clear differences in effectiveness and cost-effectiveness between hospital-at-home and usual hospital care, informal caregiver preferences play an important role. This study investigated informal caregiver strain, satisfaction and preferences for place of treatment with a community-based hospital-at-homes scheme for COPD exacerbations.

Method

The study was part of a larger randomised controlled trial. By randomisation, patients were allocated to usual hospital care or hospital-at-home, which included discharge at day 4 of admission, followed by home treatment with homes visits by community nurses until day 7 of treatment. Patients allocated to usual hospital care received care as usual in the hospital and were discharged at day 7. Patients were asked if they had an informal caregiver and who this was. Patients and their caregivers were followed for 90 days. Informal caregiver strain was assessed with the caregiver strain index. Satisfaction and preference were assessed using questionnaires. All measurements were performed at the end of the 7-day treatment and the end of the 90-days follow-up.

Findings

Of the 139 patients, 124 had an informal caregiver, of whom three-quarter was the patients’ spouse. There was no significant difference in caregiver strain between hospital-at-home and usual hospital care at both time points (mean difference at T + 4 days 0.47 95% CI −0.96 to 1.91, p = 0.514; mean difference at T + 90 days 0.36 95% CI −1.85 to 1.35, p = 0.634). At the end of the 7-day treatment, 33% (N = 15) of caregivers of patients allocated to hospital treatment and 71% (N = 37) of caregivers of patients allocated to home treatment preferred home treatment, if they could choose. Caregivers were satisfied with the treatment the patient received within hospital-at-home.

Conclusion

There were no differences in caregiver strain between the community-based hospital-at-home scheme and usual hospital care. Most caregivers were satisfied with the treatment. In addition to other outcomes, our results support the wider implementation of hospital-at-home for COPD exacerbations.     

Using Preoperative Assessment and Patient Instruction to Improve Patient Safety

Rates of patient transfers, cancellations, and patient visits to the emergency department after discharge are quality metrics for ambulatory surgery centers. To improve these metrics, it is imperative to establish best practices for conducting preoperative assessments, including identifying key patient conditions (ie, obstructive sleep apnea, cardiovascular disease, reactive airway disease, obesity). To guide appropriate patient selection, practitioners should review the patient's allergies and sensitivities, alcohol use, medications, and medical history. To help ensure good patient outcomes, it is imperative to provide complete preoperative instructions (eg, NPO guidelines, medications, what to bring, cancellation instructions) and discharge instructions (eg, postoperative medications, appropriate activity restrictions, diet, surgical and anesthetic side effects, special circumstances [eg, regional blocks], symptoms of possible complications, treatment and tests, access to postdischarge follow-up care). Generally, the routine outpatient surgical patient is discharged home; however, there are circumstances that occasionally necessitate transfer or admission to a higher level of care. For transfers, ambulatory surgery centers should adhere to applicable federal and state guidelines and should have a clear policy in place to guide transfers.     

996例纤维乳管镜诊治分析

目的探讨乳管镜诊治乳管内早期病变的价值。方法2009年1月-2011年12月,采用日本FiberTeehr-FT-201型乳管镜对996例非乳汁性乳头溢液及部分无乳头溢液进行诊断、灌洗治疗、定位、活检。其中镜下植入定位针532例,灌洗治疗197例,取活检114例。结果996例乳管镜诊断乳头状瘤和乳头状瘤病697例,似乳管癌99例,乳管积液扩张123例,平坦型红斑病变4例,毛细血管扩张2例,闭塞性乳管炎50例,余21例乳管镜除乳管扩张外未见明显异常。镜下植入定位针准确扎入瘤体460例,准确率86．5％（460／532）。镜下灌洗治愈乳管炎196例,治愈率99．5％（196／197）。镜下活检成功取出瘤体组织98例,成功率86．0％（98／114）。结论乳管镜可作为诊治乳管内早期病变的首选措施,其所起到的作用是B超、钼靶所不及的。