Deep venous thrombosis: clinically silent in the intensive care unit

PURPOSE: The reliability of clinical signs and the physical examination in the evaluation of deep venous thrombosis (DVT) in the critically ill is unknown. The purpose of this study was to determine the diagnostic properties of clinical examination for signs of DVT in a cohort of medical-surgical intensive care unit (ICU) patients using screening compression ultrasonography as a reference standard. MATERIALS AND METHODS: We prospectively included patients older than 18 years with an expected length of ICU stay of more than 72 hours. Patients underwent bilateral lower limb screening compression ultrasound twice weekly and structured physical examination twice weekly by 2 independent trained research coordinators blinded to the ultrasonography results. We classified patients according to 2 methods: method 1, a DVT Risk Stratification System of 3 categories and method 2, a DVT Risk Score, both of which use the history and physical examination to stratify patients for their risk of DVT. RESULTS: We included 239 patients in our study, 32 of whom had DVT based on the results of their compression ultrasound. We excluded 7 patients with DVT on ICU admission and 2 who did not undergo any structured examinations. We matched controls with cases (9:1) based on duration of ICU stay. Cases and controls were then allocated to low, moderate, and high risk strata for DVT. Using method 1, the area under the receiver operating characteristic curve (AUC) was 0.57 (95% CI, 0.33-0.78, P = .01). Using method 2, the AUC was 0.59 (95% CI, 0.42-0.75, P = .02). An AUC of 1.0 indicates an ideal test, and AUC of 0.50 indicates a test with no diagnostic utility. CONCLUSIONS: The history and physical examination for DVT are not useful in detecting lower limb DVT in the ICU.     

Thrombocytopenia in medical-surgical critically ill patients: prevalence, incidence, and risk factors

OBJECTIVE: The purpose of this study is to describe the prevalence, to analyze the incidence and independent risk factors for thrombocytopenia, and to examine the impact of thrombocytopenia developing in the intensive care unit (ICU) on patient outcome in a well-defined cohort of critically ill patients in a medical-surgical ICU. MATERIALS AND METHODS: As part of a prospective cohort study examining the frequency and clinical importance of venous thromboembolism in the ICU, we enrolled consecutive patients older than 18 years expected to be in the ICU for more than 72 hours. Exclusion criteria were an admitting diagnosis of trauma, orthopedic surgery or cardiac surgery, pregnancy, and life support withdrawal. Patients had platelet counts performed as directed by clinical need. We defined thrombocytopenia as a platelet count of less than 150 x 10(9)/L and severe thrombocytopenia as a platelet count of less than 50 x 10(9)/L. Protocol-directed care included routine thromboprophylaxis and twice weekly screening ultrasonography of the legs. Patients were followed to hospital discharge. RESULTS: Of the 261 enrolled patients, 121 (46%, 95% confidence interval [CI], 40%-53%) had thrombocytopenia (62 on ICU admission and 59 acquired during their ICU stay). Patients who developed a platelet count less than 150 x 10(9)/L during their ICU stay had higher ICU and hospital mortality (P = .03 and .005, respectively), required longer mechanical ventilation (P = .05), and were more likely to receive platelets (P < .001), fresh frozen plasma (P = .005), and red blood cell transfusions (P = .004) than patients who did not develop thrombocytopenia. The only independent risk factors for thrombocytopenia developing during the ICU stay were administration of nonsteroidal anti-inflammatory drugs before ICU admission (hazard ratio, 2.8; 95% CI, 1.3-6.0) and dialysis during the ICU stay (hazard ratio, 3.1; 95% CI, 1.2-7.8). Of the 33 patients who underwent 36 tests for heparin-induced thrombocytopenia, none tested positive. CONCLUSIONS: We found that about 50% of the patients admitted to the ICU had at least one platelet count of less than 150 x 10(9)/L during their ICU stay. Patients who developed thrombocytopenia were more likely to die, required longer duration of mechanical ventilation, and were more likely to require blood product transfusion. Heparin-induced thrombocytopenia was frequently suspected but did not develop in these critically ill patients.     

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.     

Cancer and thrombosis: an increasingly important association

Introduction The association of cancer and venous thromboembolism (VTE) becomes increasingly important. VTE has been recognised as an increasingly frequent complication in cancer care. Furthermore, recent clinical trials have shown that therapy and prophylaxis of VTEs with low-molecular weight heparin (LMWH) is, in general, superior to oral anticoagulation with warfarin. Also, prolonged therapy of or prophylaxis for VTE in cancer patients seems to be associated with an improved outcome. Discussion Research on patient preferences for therapy and prophylaxis of VTE is still rare; but it seems clear that, as in other areas, cancer patients wish to be involved in the decision-making process. Patients seem to accept LMWH over oral anticoagulation despite the need for subcutaneous injections. Conclusion Cancer and thrombosis/hypercoagulability is an increasingly important association. The use of antithrombotics in cancer patients warrants increased attention since it’s importance seems underecognized. An erratum to this article can be found at     

Identification of intraluminal thrombus by ultrasonography in emergency department patients with acute deep venous thrombosis

Background

Traditionally, the diagnosis of deep venous thrombosis (DVT) using duplex ultrasonography (DU) has relied on the absence of venous compressibility. Visualization of an intraluminal thrombus is considered an uncommon finding.

Objectives

The purpose of this study is to determine the frequency of intraluminal thrombus in emergency department (ED) patients diagnosed with acute DVT.

Methods

Retrospective chart review of adult ED patients with DU examinations demonstrating acute DVT. Patients with chronic DVT or patients in whom DU did not demonstrate DVT were excluded from data analysis. Study reports and ultrasound images were reviewed and analyzed for the presence of intraluminal thrombus.

Results

There were 189 patients who met inclusion criteria, of which 160 (85%) were found to have intraluminal thrombus.

Conclusion

Intraluminal thrombi are present in the majority of patients in our ED in whom acute DVT is identified by DU.     

间歇性充气加压装置预防静脉血栓栓塞症有效性和安全性评估的系统评价再评价

目的对涉及充气加压装置(PCD)在静脉血栓栓塞症(VTE)预防中的有效性和安全性的系统评价进行再评价。方法计算机检索Cochrane Library、PubMed、Embase、CNKI、中国生物医学文献数据库、万方数据库,检索时间从建库至2019年3月31日,检索PCD与其他物理预防措施、药物预防措施相比较的相关系统评价和Meta分析,由2名研究者独立进行文献筛选、资料提取和质量评价过程,采用AMSTAR工具对纳入的研究进行方法学质量评价,采用GRADE系统对结局指标进行质量评价。结果最终纳入15篇系统评价/Meta分析,包括8篇中文研究、7篇英文研究。其中11篇发表在2012年之后,方法学质量评价显示3篇研究满足AMSTAR的11个评价条目,其他研究均在不同方面存在缺陷。中等质量的证据显示,间歇性充气加压装置(IPC)预防VTE有效,联合药物预防可降低单独使用药物预防引起的出血等不良事件发生率。IPC用于VTE预防时,应按照目前的临床指南使用。目前指导选择特定设备或设备类型的证据基础是有限的。结论IPC在预防VTE过程中是安全有效的,但该结论的论证仍需大样本、高质量的研究进一步证实。     

Central adjudication of venous ultrasound in VTE screening trials: reasons for failure

Summary. Background: The accuracy of screening ultrasound for venous thrombosis in asymptomatic patients is still a matter of debate. The VENUS study evaluated the accuracy of centrally adjudicated venous ultrasound against venography in patients after major orthopedic surgery and found the sensitivity of ultrasound to be poor for both proximal and distal deep vein thrombus (DVT). Objectives: To evaluate whether thrombus characteristics such as location or size influence the diagnostic performance of centrally adjudicated venous ultrasound. Methods: All false negative sonograms of the VENUS study were re‐evaluated against the corresponding venograms. Discrepancies were categorized into types of diagnostic failures. Within these categories, thrombus characteristics such as location, length or size of thrombus were evaluated. Results: One hundred and twelve pairs of discrepant ultrasound and venography documents were compared with 28 pairs with concordant results. Discrepancies were caused by local documentation failure (37.5%), failure of the ultrasound method (43.7%) and failure of the central adjudication process (18.7%). The overall size of thrombi was small, which caused about 40% of all sonographic failures with a detection threshold of five Marder points, a thrombus length of 9.5 cm and a number of 3.5 pathological compression manoeuvres. Proximal or distal location of DVT did not affect thrombus detection. Conclusion: If centrally adjudicated ultrasound is to be used in future VTE screening trials, training of local sonographers and central adjudicators needs to be intensified, because asymptomatic DVTs seem to be small and ultrasound sensitivity depends on the number of pathological compression manoeuvres documented in the ultrasound document. In contrast, distal or proximal thrombus location itself does not influence sensitivity.     

彩色多普勒超声在下肢深静脉栓塞诊断中的应用价值

目的探讨彩色多普勒超声诊断下肢深静脉血栓(DVT)的应用价值。方法彩色多普勒超声对212例临床怀疑DVT的患者进行血管超声检查,观察双下肢深静脉的走行、管径、血管内壁、管腔内透声及血栓回声特征。结果彩色多普勒超声明确诊断201条深静脉血栓形成。彩超表现为患肢深静脉管径增宽,管腔内可见絮状弱回声、实质低回声或不均匀低弱回声,管腔结构不清,探头轻压不能闭合,病变部位无彩色血流信号或可见狭窄细条状的彩色血流信号。结论彩色多普勒超声能及时诊断急性DVT,为临床提供及时、准确、安全、无创的检查手段,对早期诊断、指导治疗、减少并发症具有重要的临床应用价值。     

Vena caval thromboses

Background

Patients with vena caval (VC) thrombosis have been reported with a variety of clinical presentations, which may create a diagnostic challenge for physicians.

Objective

The objective of the study was to evaluate the clinical characteristics of patients with VC thrombosis.

Patients and Methods

Files and all imaging methods of consecutive patients with superior or inferior VC thrombosis with or without pulmonary embolism (PE) between January 26, 2001, and May 12, 2006, were retrospectively studied in detail.

Results

In our series, VC thromboses within the inferior and superior VC were detected in 28 patients, mostly by combined computed tomographic venography and spiral computed tomographic pulmonary angiography. Nine of these 28 patients (32.1%) had VC thromboses without PE (7 patients with isolated and 2 patients with nonisolated VC thrombosis). Key symptoms and findings in the 9 patients without PE were unexplained dyspnea and tachypnea, respectively.

Conclusions

Many patients with VC thrombosis do not have peripheral vein thrombosis. Moreover, nearly one third of patients with VC thrombosis have negative pulmonary angiograms but do have dyspnea and tachypnea.     

PDCA循环管理法在超声科"危急值"管理中的应用

目的探讨PDCA循环管理法在超声科"危急值"管理中的应用价值。 方法对实行PDCA循环后2015年1月至2019年1月超声科"危急值"数据进行质量现状分析，采用χ²检验对超声科"危急值"的报告率、知晓率、书写合格率及临床处理及时率进行比较，评估PDCA循环管理法应用后的效果。 结果应用PDCA循环管理法后超声科"危急值"报告率分别为96.4%、98.0%、94.5%、96.7%，知晓率分别为63.2%、78.6%、84.8%、92.2%，书写合格率分别为70.4%、77.2%、85.3%、94.0%，临床处理及时率分别为50.9%、71.7%、81.1%、85.5%，超声科"危急值"知晓率、书写合格率及临床处理及时率均得到显著提高，差异均有统计学意义（χ²=12.464、38.184、52.926，P均<0.05）。 结论应用PDCA循环管理法可明显改进超声科"危急值"管理质量。     

Severe massive pulmonary thromboembolism: a case reinforcing the crucial role of point-of-care ultrasound in emergency settings

Patients with high-risk pulmonary embolism (PE) have a significant mortality rate, and thus a timely diagnosis and early treatment are essential to improve outcomes. Since these groups of patients are often too ill to be transferred to the radiology department to perform a chest computed tomography angiography, offering a feasible, reliable and bedside diagnostic tool may be desirable in this setting. We report the case of a middle-aged woman presenting to the emergency department with shock who was diagnosed with massive pulmonary embolism based on point-of-care ultrasound (POCUS). We are hereby discussing the usefulness of POCUS in this subset of PE patients, highlighting the importance of considering ultrasound as a first-line diagnostic (and monitoring) tool for each patient with suspicion of massive PE.Electronic supplementary materialThe online version of this article (10.1007/s40477-019-00417-x) contains supplementary material, which is available to authorized users.