Epidemiology of severe acute respiratory syndrome (SARS): adults and children

Severe acute respiratory syndrome (SARS) is a newly described respiratory infection with pandemic potential. The causative agent is a new strain of coronavirus most likely originating from wild animals. This disease first emerged in November 2002 in Guangdong Province, China. Early in the outbreak the infection had been transmitted primarily via household contacts and healthcare settings. In late February 2003 the infection was transmitted to Hong Kong when an infected doctor from the mainland visited there. During his stay in Hong Kong at least 17 guests and visitors were infected at the hotel at which he stayed. By modern day air travel, the infection was rapidly spread to other countries including Vietnam, Singapore and Canada by these infected guests. With the implementation of effective control strategies including early isolation of suspected cases, strict infection control measures in the hospital setting, meticulous contact tracing and quarantine, the outbreak was finally brought under control by July 2003. In addition, there were another two events of SARS in China between the end of December 2003 and January 2004 and from March to May 2004; both were readily controlled without significant patient spread.     

Severe acute respiratory syndrome (SARS): chest radiographic features in children

Background Severe acute respiratory syndrome (SARS) is a recently recognized condition of viral origin associated with substantial morbidity and mortality rates in adults. Little information is available on its radiologic manifestations in children.Objective The goal of this study was to characterize the radiographic presentation of children with SARS.Materials and methods We abstracted data (n=62) on the radiologic appearance and course of SARS in pediatric patients with suspect (n=25) or probable (n=37) SARS, diagnosed in five hospital sites located in three cities: Toronto, Singapore, and Hong Kong. Available chest radiographs and thoracic CTs were reviewed for the presence of the following radiographic findings: airspace disease, air bronchograms, airways inflammation and peribronchial thickening, interstitial disease, pleural effusion, and hilar adenopathy.Results A total of 62 patients (suspect=25, probable=37) were evaluated for SARS. Patient ages ranged from 5.5 months to 17 years and 11.5 months (average, 6 years and 10 months) with a female-to-male ratio of 32:30. Forty-one patients (66.1%) were in close contact with other probable, suspect, or quarantined cases; 10 patients (16.1%) had recently traveled to WHO-designated affected areas within 10 days; and 7 patients (11.2%) were transferred from other hospitals that had SARS patients. Three patients, who did not have close/hospital contact or travel history to affected areas, were classified as SARS cases based on their clinical signs and symptoms and on the fact that they were living in an endemic area. The most prominent clinical presentations were fever, with a temperature over 38 °C (100%), cough (62.9%), rhinorrhea (22.6%), myalgia (17.7%), chills (14.5%), and headache (11.3%). Other findings included sore throat (9.7%), gastrointestinal symptoms (9.7%), rigor (8.1%), and lethargy (6.5%). In general, fever and cough were the most common clinical presentations amongst younger pediatric SARS cases (age<10 years), whereas, in addition to these symptoms, headache, myalgia, sore throat, chills, and/or rigor were common in older patients (age10 years). The chest radiographs of 35.5% of patients were normal. The most prominent radiological findings that were observed in the remaining patients were areas of consolidation (45.2%), often peripheral with multifocal lesions in 22.6%. Peribronchial thickening was noted on chest radiographs of 14.5% of patients. Pleural effusion was observed only in one patient (age 17 years and 11.5 months), whereas interstitial disease was not observed in any patient.Conclusion In pediatric cases, SARS manifests with nonspecific radiographic features making radiological differentiation difficult, especially from other commonly encountered childhood respiratory viral illnesses causing airspace disease. The radiographic presentation of suspected SARS cases ranged from normal to mild perihilar peribronchial thickening. The radiographic presentations, as expected, were relatively more pronounced in the SARS probable cases.     

Severe acute respiratory syndrome (SARS)

Several cases of life threatening respiratory disease with no identifiable cause were reported from Guangdong Province, China; these were soon followed by reports from many other countries. The disease was named as severe acute respiratory syndrome (SARS). A novel coronavirus, isolated from the respiratory secretions of patients, has been implicated in the causation of SARS. The modes of transmission include droplet spread, close contact, and Fomites; shedding of virus from respiratory tract is the primary mode of transmission. SARS clinically presents with high-grade fever, chills and rigors, myalgia, headache, cough with or without sputum production, dyspnea, and dizziness. Chest radiographs reveal unilateral or bilateral, predominantly peripheral, areas of consolidation progressing with in a short time of bilateral patchy consolidation. Preliminary reports suggest a milder illness in young children. The case definition of probable SARS cases, laboratory investigations and precautions for prevention of spread are discussed.     

Severe acute respiratory syndrome (SARS) in a paediatric cluster in Singapore

Background Severe acute respiratory syndrome (SARS) is a major infectious disease pandemic that occurred in early 2003, and one of the diagnostic criteria is the presence of chest radiographic findings.Objective To describe the radiographic features of SARS in a cluster of affected children.Materials and methods The chest radiographs of four related children ranging in age from 18 months to 9 years diagnosed as having SARS were reviewed for the presence of air-space shadowing, air bronchograms, peribronchial thickening, interstitial disease, pleural effusion, pneumothorax, hilar lymphadenopathy and mediastinal widening.Results Ill-defined air-space shadowing was the common finding in all the children. The distribution was unifocal or multifocal. No other findings were seen on the radiographs. None of the children developed radiographic findings consistent with acute respiratory distress syndrome. All four children showed significant resolution of the radiographic findings 4–6 days after the initial radiograph.Conclusions Early recognition of these features is important in implementing isolation and containment measures to prevent the spread of infection. SARS in children appears to manifest as a milder form of the disease as compared to adults.     

Severe acute respiratory syndrome (SARS) in neonates and children

Severe acute respiratory syndrome (SARS) runs a more benign course in children during the acute phase. Infants born to mothers with the disease did not acquire the infection through vertical transmission. The treatment strategy for children with SARS has not been standardised and is based on adult experience. Thus far, no deaths have been reported in the paediatric age group. Exercise impairment and residual radiological abnormalities were present six months after diagnosis. It is important to assess these patients on a regular basis to detect and provide appropriate management for any persistent or emerging long term sequelae in the physical, psychological, and social domains. This review describes the current understanding of SARS coronavirus infection in newborns and children.     

呼吸指数及氧合指数的监测在儿童急性呼吸窘迫综合征中的应用

目的通过监测呼吸指数(RI)及氧合指数(OI)在儿童急性呼吸窘迫综合征(ARDS)中的变化,探讨RI及OI在ARDS的诊断及治疗中的价值。方法将2002年1月~2004年12月在上海儿童医学中心PICU治疗的12例ARDS患儿(实验组),与同期住院治疗的20例肺炎合并急性呼吸衰竭的患儿(对照组)进行回顾性研究,监测两组患儿在机械通气早期(上机2 h内)、中期(上机48~72 h间)以及撤机前(撤机前2 h到撤机前0.5 h)的RI、OI、肺泡-动脉血氧分压差[P(A-a)O2]、血氧饱和度(SaO2)、动脉血氧分压(PaO2)的变化。结果两组患儿在机械通气早期及中期RI、OI、P(A-a)O2比较有显著性差异(P<0.01),而SaO2、PaO2比较差异无显著性(P>0.05);在撤机前两组患儿各项指标比较均无差异(P>0.05)。结论RI、OI可作为ARDS早期诊断、疗效观察及指导撤机的指标。     

小儿心内直视手术后急性呼吸窘迫综合征的危险因素与防治对策

Objective To analyze the risk factors,prevention and management strategies of acute respiratory distress syndrome(ARDS)after cardiopulmonary bypass(CPB).Methods Between January 2001 and October 2008,1 408 patients undergoing open heart surgery were recruited for study.Univariate and multivariate logistic regression analysis were used to identify the risk factors.Results Thirty-two patients (2.27%)developed ARDS.The mortality for ARDS was 46.9 %(15/32).Univariate risk factors included cyanotic congenital heart disease,CPB lime,aortic cross-clamping time,mechanical ventilation time,the volume of postoperative drainage per kilogram of body weight,perioperative unexpected events and postoperative complications.Multivariate logistic regression analysis showed that CPB time ＞ 180 rain,postoperative drainage volume per kilogram of body weight ＞ 18 ml,perioperative unexpected events,postoperative multiple organ dysfunction syndrome(MODS)were risk factors.Condusion Active and effective treatments should be carried out in the children with high risk factors of ARDS following open heart operation.It would play an important role in the prevention,early diagnosis and management of ARDS.     

连续性血液净化治疗小儿急性呼吸窘迫综合征

目的 探讨连续血液透析滤过(CVVHDF)对急性呼吸窘迫综合征(ARDS)患儿氧合、血流动力学以及凝血功能的影响.方法 2004年1月至2007年11月复旦大学附属儿科医院收治的11例ARDS患儿为研究对象.所有患儿接受机械通气等治疗,同时行CVVHDF,于治疗前(0 h),治疗后2 h(2 h)、4 h(4 h)、6 h(6 h)记录患儿心率(HR)、平均动脉压(MAP),采血测动脉血气;于治疗前(0 h),治疗后2 h(2 h)、6 h(6 h)采血行血小板计数、D-二聚体和血浆纤维蛋白原检测.各指标各时点间比较采用Stata7.0软件行数据统计分析.结果 所有患儿于CVVHDF前均存在氧合指数低、低血压、心率偏快,D-二聚体增高.经CVVHDF治疗后,患儿心率、血压、氧合指数好转,各时点间比较差异有显著性(P＜0.05).治疗中患儿血小板计数进行性下降,D-二聚体降低,各时点间比较差异有显著性(P＜0.05).结论 CVVHDF能有效改善ARDS患儿氧合和稳定血流动力学;对凝血功能无显著不利影响.     

儿童急性呼吸窘迫综合征预后及其影响因素分析

目的：了解儿童急性呼吸窘迫综合征（ARDS）的预后,探讨影响其预后的相关因素。方法：纳入78 例 ARDS 患儿,追踪确诊后 30 d 内生存状况。结果：（1）78 例 ARDS 患儿中,死亡 51 例,生存 27 例,30 d 生存率为 35%,平均生存 14.4 d,中位生存时间 8 d,确诊 ARDS 后 3 d 内为死亡的高峰期。（2）死亡患儿和生存患儿在年龄、原发病、新生儿肺透明膜病的构成比、小儿危重病例评分（PCIS）、机械通气时间、氧合指数（PaO2/FiO2）、WBC 和受累器官数目方面差异存在统计学意义（P＜0.05或0.01）。Cox多因素分析显示年龄（HR 3.924~3.938）、原发病（HR=1.817）和 PCIS（HR=0.469）是发生死亡的危险因素。结论：ARDS 后 3 d 内是死亡的高危期。年龄、原发致病因素和 PCIS 是影响 ARDS 患儿预后的独立因素。     

小儿心内直视手术后急性呼吸窘迫综合征的危险因素与防治对策

目的 分析小儿心内直视手术后发生急性呼吸窘迫综合征(ARDS)的危险因素及探讨其防治对策.方法 以2001年1月至2008年10月间连续1 408例施行先天性心脏病(先心病)手术患儿为研究对象,进行术后ARDS危险因素的单因素分析和多因素Logistic回归分析.结果 术后发生ARDS 32例,发生率为2.27%.术后ARDS患儿病死率为46.9%.单因素分析显示:紫绀型先心病、体外循环时同、主动脉阻断时间、呼吸机通气时间、每公斤体质量引流液总量、围手术期意外、术后并发症与术后ARDS有关.经多因素Logistic回归分析显示:体外循环时间超过180 min、每公斤体质量引流液总量超过18 ml、围术期发生意外、术后多器官功能衰竭为小儿心内直视手术后ARDS的危险因素.结论 对于具有ARDS高危因素的心内直视手术患儿,应采取积极的防治措施,这对防止心内直视手术后发生的ARDS具有重要的意义.     

Severe acute respiratory syndrome (SARS): a review of the history,epidemiology, prevention,and concerns for the future

During the first part of 2003, the world experienced the first epidemic of the 21st century with the emergence of a new and readily transmissible disease. The disease, severe acute respiratory syndrome (SARS), spread quickly and caused numerous deaths, as well as public panic. This article provides a brief review of the initial history of the epidemiology, as well as of the clinical definition, occurrence in the pediatric population, etiology, prevention, drug studies, and considerations for the future.     

新生儿急性肺损伤的诊断与治疗策略

急性肺损伤(ALI)和急性呼吸窘迫综合征(ARDS)是新生儿临床的常见危重症,随着对ALI/ARDS实验与临床研究的不断深入,人们对新生儿ALI/ARDS的认识明显提高,文章提出了新生儿ALI/ARDS诊断依据与治疗策略,在控制原发疾病基础上,应用肺保护性通气策略、加强液体管理、降低肺动脉压力和给予抗炎治疗等,对提高新生儿ALI/ARDS抢救成功率具有重要意义.     

急性呼吸窘迫综合征患儿肺力学特点

急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)的病因不一,发病机制各有所异,病情进展过程中肺力学的改变存在个体差异。顺应性、压力、容量等的变化与病因、病情轻重、年龄等密切相关。正确采用肺保护性通气策略、合理调节呼吸机参数、减少呼吸机相关性肺损伤是提高ARDS救治成功率的关键。因此,在ARDS机械通气治疗中必须高度注意患儿肺力学的特点和变化。     

肺表面活性物质在儿童急性呼吸窘迫综合征的应用

肺表面活性物质(pulmonary surfactant,PS)是由Ⅱ型肺泡上皮细胞合成分泌的脂质蛋白混合物,主要功能是降低肺泡气-液界面表面张力.急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)时多种原因引起PS的量和质出现变化,导致其功能异常.外源性PS替代治疗可以改善儿童ARDS肺部气体交换,但提高存活率作用不肯定.这可能与ARDS病因、PS成分、给药方法、时机、剂量及次数等不同有关.目前不推荐PS作为儿童ARDS的常规治疗方法.     

急性呼吸窘迫综合征机械通气策略的新进展

急性呼吸窘迫综合征（ARDS）机械通气的目标是保证足够的氧合和最小的呼吸机相关肺损伤。无创机械通气应慎用于ARDS。小潮气量通气的肺保护性通气策略能降低ARDS死亡率,以驱动压为导向设置潮气量更合理。建议根据静态压力-容积曲线采用低位转折点法来确定理想的呼气末正压（PEEP）,不支持常规使用高水平PEEP。俯卧位通气、高频振荡通气和体外膜氧合技术可用于拯救重症ARDS。机械通气中保持ARDS患者自主呼吸很重要,可采用双相气道正压通气、压力支持通气和神经电活动辅助通气等辅助通气模式。不推荐补充外源性肺泡表面活性物质、吸入一氧化氮或支气管扩张剂、气道压力释放通气和部分液体通气。     

肺保护性通气策略在儿童急性呼吸窘迫综合征中的应用价值

Objective To assess the effect of lung protective ventilation on outcome of children with acute respiratory distress syndrome(ARDS).Methods Between January 1999 and December 2007,43 children with ARDS were enrolled from PICU of Shanghai Children's Medical Center and assigned to the protective-ventilation group(group A) or the conventional-ventilation group(group B).The patients in group A (from January 2004 to December 2007)received lower tidal volume(6～7 ml/kg) and high levels of positive end-expiratory pressure(PEEP),and optimal oxygenation was achieved by adjusting FiO2 and PEEP.The patients in group B(from January 1999 to December 2003) received relatively higher tidal volume(8～12 mL/kg) with lower PEEP(2～6 cm H2O),and optimal oxygenation was achieved by adjusting FiO2.Tidal volume,PEEP,arterial blood gas,mortality and the number of ventilator-free days were compared between the two groups.Results Since protective ventilation was adopted after 2004,tidal volume was significantly lower in group A[(7.09±1.66)ml/kg]as compared with that in group B[(9.82±2.31) ml/kg](P=0.001).PEEP was significantly higher in group A[(7.15±2.08) cm H2O]as compared with that of group B[(5.40 + 1.84) cm H2O](P=0.021).The mortality was 30.3% in group A and 60.0% in group B.The number of ventilator-free days were(10.88±8.84) d in group A and(8.40±10.86) d in group B.Although mortality was lower and number of ventilator-free days was greater in group A,no significant differences were found between the two groups(P＞0.05).Conclusion Lung protective ventilation may improve the outcome for pediatric patients with ARDS,however,larger trials are required before a definite conclusion can be reached.     

Childhood severe acute respiratory syndrome, coronavirus infections and asthma

Severe acute respiratory syndrome (SARS) is a new infectious disease caused by a novel coronavirus. Children appear to be less susceptible to the SARS coronavirus, although the other non-SARS coronaviruses can cause respiratory infections in adults and in children of all ages. The exact reasons as to why SARS preferentially affects adults, and not children, are still unknown. Many hypotheses exist and need to be explored. During the outbreak of SARS, there did not appear to be an increase in asthma exacerbations in children.