Pulmonary embolism

Pulmonary embolism (PE) remains one of the most challenging medical diseases in the emergency department. PE is a potentially life threatening diagnosis that is seen in patients with chest pain and/or dyspnea but can span the clinical spectrum of medical presentations. In addition, it does not have any particular clinical feature, laboratory test, or diagnostic modality that can independently and confidently exclude its possibility. This article offers a review of PE in the emergency department. It emphasizes the appropriate determination of pretest probability, the approach to diagnosis and management, and special considerations related to pregnancy and radiation exposure.     

Pulmonary issues in acute and critical care: pulmonary embolism and ventilator-induced lung injury

Many patients admitted to acute care hospitals are at risk for VTE. Nurses play a pivotal role in prevention of VTE events by assessing risk and implementing prophylactic interventions, promptly recognizing and reacting to signs and symptoms of DVT and PE, and collaborating with other team members to ensure rapid treatment ensues. When patients require mechanical ventilation, nurses need to remain alert for complications indicative of VILI, effectively communicate assessment findings to other team members and confidently implement nursing and ordered medical interventions to promote the best possible patient outcomes.     

Pulmonary air embolism

Pulmonary air embolism is a well-known consequence of surgery, trauma, diving, and aviation. This article reviews the physiological effects, means of detection and methods of prevention and treatment of pulmonary air embolism. The primary physiological effects are elevated pulmonary artery pressures, increased ventilation-perfusion inhomogeneity, and right ventricular failure. The degree of physiological impairment depends on the volume of gas entrained, the rate of entrainment, the type of gas entrained, and the position of the patient when the embolism occurs. Transesophageal echocardiography is the most sensitive method of detection, but it is invasive. Precordial Doppler ultrasound is almost as sensitive and poses no risk to the patient. End-tidal carbon dioxide monitoring is used on all patients and is a moderately sensitive method of detection, which is useful during surgeries that have a low incidence of air embolism. For high-risk procedures, precordial Doppler ultrasound and a multi-orifice right heart catheter should be used to detect and treat pulmonary air embolism. Prevention measures include volume expansion, careful positioning, positive end-expiratory pressure, military anti-shock trousers, and jugular venous compression. Treatment of pulmonary air embolism includes flooding the surgical site with saline, controlling sites of air entry, repositioning the patient with the surgical site below the right atrium, aspiration of air from a central venous catheter, cessation of inhaled nitrous oxide, and resuscitation with oxygen, intravenous fluids, and inotropic agents. Some hypotheses on the effects of air in the pulmonary vasculature and investigational treatment options are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

脊柱外科手术后静脉血栓栓塞症自然发生率的临床研究

目的 分析脊柱手术后静脉血栓栓塞症（VTE）的自然发生率,探讨采取干预措施抗凝以预防VTE的必要性;结合文献,分析VTE的发生与手术方式、体位、时间等关系,指导临床改进相关环节.方法 2011年1月至2012年1月收治的接受脊柱手术患者168例,术前进行血常规、凝血指标及双下肢静脉彩超检查.术后复查双下肢静脉彩超.随访时间3个月.如果彩超怀疑深静脉血栓（DVT）,行下肢静脉造影确诊;如果高度怀疑肺栓塞（PE）形成,行肺血管造影确诊.统计患者资料及VTE例数.通过SPSS 11.0软件,利用x2检验、Mann-Whitney检验分析.结果 168例患者中确诊VTE1例,无PE病例.脊柱手术后VTE自然发生率为0.60％.尝试分析VTE阳性组与阴性组在性别、年龄、体重、手术时间、部位、入路、失血量、卧床时间等方面是否存在统计学差异.但由于VTE阳性例数少,随机性大,未能进行分析.结论 本次研究结果与文献报道类似,显示脊柱手术围手术期不采用抗凝措施下,VTE自然发生率较低;脊柱手术后对于无VTE症状以及不存在VTE危险因素的患者不需要行双下肢静脉彩超检查、血管造影检查以及常规抗凝处理.     

Epidemiology and incidence: the scope of the problem and risk factors for development of venous thromboembolism

The proportion of hospitalized patients with pulmonary embolism (PE) is increasing. Whether this represents more admissions with PE or more diagnoses made in hospitalized patients is uncertain. The proportion of hospitalized patients with deep venous thrombosis has decreased precipitously as a result of home treatment. Asians and Native Americans have a lower incidence of PE than whites or African Americans. The incidence of PE increases exponentially with age, but no age group, including infants and children, is immune. Several medical illnesses have now been shown to be associated with a higher risk for venous thromboembolism. Epidemiologic data and new information on risk factors provide insight into making an informed clinical assessment and evaluation for antithrombotic prophylaxis.     

Burden of illness in venous thromboembolism in critical care: a multicenter observational study

PURPOSE: The frequency of clinically diagnosed venous thromboembolism (VTE) including deep venous thrombosis (DVT) and pulmonary embolism (PE) in medical-surgical critically ill patients is unclear. The objectives of this study were to estimate the prevalence and incidence of radiologically confirmed DVT and PE in medical-surgical intensive care unit (ICU) patients and to determine the impact of prophylaxis on the frequency of these events. MATERIALS AND METHODS: In a retrospective observational cohort study in 12 adult ICUs, we identified prevalent cases (diagnosed in the 24 hours preceding ICU admission up to 48 hours post-ICU admission) and incident cases (diagnosed 48 hours or more after ICU admission and up to 8 weeks after ICU discharge) of upper or lower limb DVT or PE. Deep venous thrombosis was diagnosed by compression ultrasound or venogram. Each DVT was classified as clinically suspected or not clinically suspected in that the latter was diagnosed by scheduled screening ultrasonography. Pulmonary embolism was diagnosed by ventilation-perfusion lung scan, computed tomography pulmonary angiography, echocardiography, electrocardiography, or autopsy. RESULTS: Among 12,338 patients, 252 (2.0%) patients had radiologically confirmed DVT or PE and another 47 (0.4%) had possible DVT or PE. Prevalent DVTs were diagnosed in 0.4% (95% confidence interval [CI], 0.3%-0.5%) of patients and prevalent PEs were diagnosed in 0.4% (95% CI, 0.3%-0.6%). Incident DVTs were diagnosed in 1.0% (95% CI, 0.8%-1.2%) of patients, and incident PEs were diagnosed in 0.5% (95% CI, 0.4%-0.6%). Of patients with incident VTE, 65.8% of cases occurred despite receipt of thromboprophylaxis for at least 80% of their days in ICU. The median (interquartile range) ICU length of stay was similar for patients with DVT (7 [3-17]) and PE (5 [2-8]). For all patients with VTE, ICU mortality was 16.7% (95% CI, 12.0%-21.3%) and hospital mortality was 28.5% (95% CI, 22.8%-34.1%). CONCLUSIONS: Venous thromboembolism appears to be an apparently infrequent, but likely underdiagnosed problem, occurring among patients receiving prophylaxis. Findings suggest the need for increased suspicion among clinicians, renewed efforts at thromboprophylaxis, and evaluation of superior prevention strategies.     

Pulmonary embolism in end stage renal disease

Clinically significant pulmonary embolism is considered to be rare in patients with end stage renal disease. Two cases with long standing renal disease on dialysis are reported where pulmonary embolism contributed significantly to morbidity and mortality. One patient had hypotension during dialysis. The differential diagnosis of sustained hypotension during dialysis or in the ICU should include pulmonary embolism. Establishing the diagnosis may require pulmonary angiography.     

48例肺动脉栓塞的诊治分析

目的:探讨肺动脉栓塞的临床特点和诊断方法,提高其诊断水平。方法:回顾分析48例确诊为肺动脉栓塞病例的临床资料。结果:肺动脉栓塞以中老年患者居多,常伴有多种危险因子(如深静脉血栓形成(35.40%)、心血管疾病(40.20%)、恶性肿瘤(12.50%)、外科手术(14.60%)后等)。临床表现不典型,多表现为不明原因的呼吸困难(93.3%)及胸痛(62.5%).部分患者可表现为休克(10.4%)及晕厥(14.6%)。动脉血气分析、血D-二聚体检查、心电图、胸片、超声心动图对肺栓塞的诊断有提示作用;而同位素肺灌注/通气扫描、螺旋CT及肺动脉造影是确诊肺栓塞的较为可靠的诊断方法。结论:肺动脉栓塞是一种常见的肺血管疾病,有较高的病死率。对有症状的高危患者应尽早给予同位素肺灌注/通气扫描和螺旋CT检查以明确诊断。     

Pulmonary Embolism Response Teams: Overview and Potential Impact of a Multidisciplinary Treatment Algorithm

Pulmonary embolism (PE), specifically submassive and massive, can be life threatening. Pulmonary embolism response teams (PERTs) are being developed across the country to facilitate rapid diagnosis and appropriate triage and provide rapid personalized treatment to reduce early cardiopulmonary decompensation and mortality. Early results are promising and demonstrate improved patient outcomes. Providers treating patients with PE should be familiar with PERT methodology to improve the diagnosis and treatment of PE.     

神经外科患者应用永久型腔静脉滤器预防肺栓塞的护理

目的评价神经外科合并下肢深静脉血栓患者放置永久型腔静脉滤器预防发生肺栓塞的效果和护理特点。方法选择我院自2005年10月至2009年11月收治的神经外科患者,在治疗过程中出现下肢深静脉血栓,选择其中60例放置永久型腔静脉滤器者,分析其护理、操作及随访资料。结果60例患者滤器置入全部一次成功,血栓急性期无有症状肺栓塞发生。随访1～36个月,未发生滤器移位等严重并发症。结论对于部分不能抗凝治疗的神经外科合并下肢深静脉血栓患者,永久型腔静脉滤器置入术是一种安全、有效的预防发生肺栓塞的临床措施。     

Pulmonary scintigraphy at the bedside in intensive care patients with suspected pulmonary embolism

Objective Performance of pulmonary scintigraphy (PS) for suspected pulmonary embolism (PE) in ICU patients normally involves the added risk of transporting unstable patients to the nuclear medicine unit (NMU) and poses technical difficulties in ventilating intubated patients. This retrospective study addresses the feasibility of performing PS as the bedside.Material and methods During a 2-year period, all ICU patients with suspected PE underwent PS at the bedside, performed with a mobile gamma-camera.^99mTc-labelled albumin macroaggregates were used for the perfusion studies. Gasified^99mTc or^81mKr gas was administered by an adapting technique in intubated patients.Results 45 patients were studied, 29 (64%) of whom were intubated and 21 (47%) of whom were in shock. PE was confirmed or excluded by PS in 49% of patients. Angiography was performed in 4 patients (8%). In the rest, a combination of low clinical and low or very low PS probabilities rendered PE highly unlikely. There was no evidence of PE in the subsequent follow-up.Conclusions In ICU patients with suspected PE, PS can be performed at the bedside with a mobile gamma-camera. The risk of transporting unstable patients can thus be avoided.     

Pulmonary embolism in sickle cell disease: a case–control study

Introduction:  A pulmonary embolism (PE) is a leading cause of mortality in hospitalized patients, yet the prevalence of PE in sickle cell disease (SCD) and its relation to disease severity or intrinsic hypercoagulability are not established. Methods:  We estimated inpatient PE incidence and prevalence among SCD and non‐SCD populations in Pennsylvania, and compared severity of illness and mortality, using Pennsylvania Health Care Cost Containment Council (PHC4) discharge data, 2001–2006. Risk factors for PE were assessed in a case–control study of discharges from the University of Pittsburgh Medical Archival Records System (MARS). Results:  The incidence of inpatient PE was higher in the SCD PA population than in the non‐SCD Pennsylvania population, 2001–2006. The PE prevalence among SCD discharges ≤ 50 years of age, 0.57%, was similar to that in non‐SCD Pennsylvania discharges, 0.60%, and unchanged after adjustment for race. Among SCD discharges, those developing PE were significantly older, with a longer length of stay, greater severity of illness and higher mortality, P < 0.001, than SCD without a PE. Among PE discharges, SCD had a similar severity of illness, P = 0.77, and mortality, P = 0.39, but underwent fewer computerized tomographic scans, P = 0.006, than non‐SCD with PE. In the local case–control study, no clinical or laboratory feature was associated with PE. Conclusions:  The incidence of PE is higher and chest computed tomography (CT) utilization is lower in SCD than non‐SCD inpatients, suggesting that PE may be under‐diagnosed.     

静脉注射毒品并发肺栓塞的诊治及误诊原因分析

目的提高对静脉注射海洛因 (静脉吸毒 )并发肺血栓栓塞症 (PTE)的认识 ,提高诊断率和治愈率。方法 1996年 1月～2 0 0 3年 7月我院收治静脉吸毒者PTE 15例 ,曾在外院诊断为多发性肺脓肿并心内膜炎、肺炎 ,来我院后经薄层螺旋CT静脉造影、放射性核素ECTV/Q显像和彩色超声心动图确诊为PTE。结果本组经抗感染治疗 10～ 14天 ,体温正常 1周后用尿激酶溶栓加抗凝治疗 2例 ,用低分子肝素钙抗凝治疗 13例。治疗后气促和胸痛消失 ,低氧血症纠正 ,4周后再次行上述影像学检查 ,15例均有不同程度改善 ,血PaO2 大于 98mmHg。结论本组误诊原因是对静脉吸毒并发PTE的临床表现认识不足。因此对静脉吸毒者要提高PTE的诊断意识 ,详细询问病史以及体格检查。薄层螺旋CT增强静脉造影或加血管重构是确诊主要手段 ,抗凝治疗有效     

Venous thromboembolic disease and hematologic considerations in obesity

Venous thromboembolic disease continues to be a major source of morbidity and mortality, with obese patients who are critically ill presenting some of the most at-risk patients. As the literature evolves, it has become clear that there is a complex relationship between obesity and thrombosis and atherogenesis. It is true that many of these conditions are reversible with weight loss; however, obesity remains on the rise. Management of obese patients must incorporate and consider these intricate changes in an attempt to improve patient outcomes.