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《Orthopaedics and Trauma》2020,34(3):120-123
Since the introduction of laminar flow to theatre systems by Charnley, it has become a necessity in arthroplasty surgery. His initial work in the 1960s and 70s created improvements in terms of reducing overall rates of periprosthetic joint replacement, but it has been hard to ascertain if this stems from the laminar flow itself or improvements in asepsis and the utilization of perioperative antibiotics. The aim of this paper is therefore to establish if laminar flow is still a necessary addition to modern theatre design, particularly in joint replacement surgery, irrespective of other surgical factors. A wide variety of studies were utilized to form an objective analysis of whether laminar flow is essential to asepsis in theatre design. It explores a number of smaller earlier studies and ends with two large trials which provide evidence that laminar flow may in fact have a deleterious effect on the potential for peri-prosthetic joint infection (PJI). The article discusses potential reasons for these findings and seeks to explain them in context of overall asepsis during joint replacement surgery.  相似文献   
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目的探讨经鼻间歇正压通气(NIPPV)在防治早产儿呼吸窘迫综合征(RDS)中的应用价值。方法选择2017年6月至2018年12月梧州市人民医院RDS早产儿90例,其中男性48例,女性42例;胎龄(29.03±0.58)周;出生体质量(996.91±98.52)g;病程(3.48±0.56)h;临床分级Ⅰ级58例,Ⅱ级32例;Apgar评分(6.85±1.06)分。依据随机数字表分为NIPPV组和持续气道正压通气(NCPAP)组,每组45例。NIPPV组给予NIPPV治疗,NCPAP组给予NCPAP治疗,若两组治疗后不能维持患儿生命体征则使用肺表面活性物质(PS)或行有创机械通气。结果NIPPV组和NCPAP组治疗12、24 h后和治疗结束时动脉血氧分压(PaO2)、氧合指数(OI)明显高于治疗前。NIPPV组治疗12、24 h后PaO2、OI明显高于NCPAP组,差异有统计学意义(P<0.05)。NIPPV组和NCPAP组治疗结束时PaO2、OI比较,差异无统计学意义(P>0.05);NIPPV组PS使用率(22.22%vs 44.44%)、有创通气率(17.78%vs 40.00%)、氧疗时间[(71.42±7.62)h vs(85.62±9.24)h]、有创通气时间[(46.78±5.32)h vs(55.27±6.14)h]、住院时间[(30.42±3.65)d vs(35.62±3.89)d]、并发症率(31.11%vs 53.33%)明显低于NCPAP组,差异有统计学意义(P<0.05)。结论NIPPV可有效改善RDS早产儿通气功能,有利于减少PS使用、有创通气及并发症,值得临床推广。  相似文献   
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The feasibility of ventilation imaging with hyperpolarized (HP) 129Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP 129Xe delivered continuously from a 129Xe polarizer. A series of 129Xe ventilation images was obtained by varying the number of breaths before the 129Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE‐treated group. The whole‐lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE‐treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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《Archives de pédiatrie》2020,27(5):270-274
ObjectivesPediatric tracheostomy has evolved significantly in the past few decades and the optimal timing to perform it in children with respiratory assistance is still debated. The objective of this study was to describe the indications, timing, complications, and outcomes of infants on respiratory support who had a tracheostomy in a tertiary pediatric intensive care unit (PICU).MethodsAll children younger than 18 months of corrected age requiring respiratory support for at least 1 week and who had a tracheostomy between January 2005 and December 2015 were included. Their demographic and clinical data and their outcomes at 24 months of corrected age were collected and analyzed after approval from the CHU Sainte-Justine ethics committee.ResultsDuring the study period, 18 children (14 preterm infants, 4 polymalformative syndromes, and 2 diaphragmatic hernias) were included. The median corrected age at tracheostomy was 97 days (0–289 days) and 94.4% were elective. The indications for tracheostomy were ventilation for more than 7 days with (61.1%) or without (38.9%) orolaryngotracheal anomaly. The median number of consultants involved per patient was 16 consultants (10–23 consultants). The median hospital length of stay was 122 days (8–365 days) before tracheostomy and 235 days (22–891 days) after tracheostomy. The median invasive ventilation time was 68 days (8–168 days) before tracheostomy and 64 days (5–982 days) after tracheostomy. In terms of complications, there were nine cases of tracheitis and five cases of tracheal granulomas. At 24 months of corrected age, 17 of 18 children survived, one of/17 was still hospitalized, three of 17 were decannulated, three of 17 received respiratory support via their tracheostomy, 11 of 17 were fed with a gastrostomy, and all had neurodevelopmental delay.ConclusionTracheostomy in infants requiring at least 1 week of ventilation is performed for complex cases and is favored for orolaryngotracheal anomalies. Clinicians should anticipate the need for developmental care in this population.  相似文献   
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