Ultrasound in the detection of venous thromboembolism

Incidence of proximal deep vein thrombosis in medical critical care patients

Background

Approximately 13-31% of medical critical care patients develop deep vein thrombosis (DVT). However, there are very few reports regarding the incidence of DVT among Asian patients without routine prophylaxis. The objectives of this study were to assess the prevalence and incidence proportion of proximal DVT in Thai medical critical care patients not receiving thrombosis prophylaxis.

Methods

We conducted a prospective cohort study in medical critical care patients admitted to Siriraj Hospital, Thailand between November 2008 and November 2009. Patients were screened for proximal DVT by duplex ultrasonography performed 48 h, 7, 14 and 28 days after admission. Primary outcomes were prevalence and incidence proportion of DVT. Factors associated with the development of proximal DVT were evaluated by multivariate analysis.

Results

Of the 158 patients enrolled in the study, 25 had proximal DVT (15.8%). Nine patients (5.7%) had DVT on the first test at 48 h, while 10 (6.3%), 2 (1.3%) and 4 (2.5%) patients had developed DVT on days 7, 14, and 28, respectively. Thus, the prevalence at the beginning of the study was 5.7% (95%CI 2.6-10.5) and the incidence proportion was 10.1% (95%CI 5.9-15.9). The multivariate analysis showed that age (odds ratio [OR] per 1-year increase was 1.04, 95% confidence interval [CI] 1.01-1.07), female gender (OR 4.05, 95%CI 1.51-12.03), femoral venous catheter (OR 11.18, 95%CI 3.19-44.83), and the absence of platelet transfusion (OR 0.07, 95%CI 0.003-0.43) were associated with the development of proximal DVT. Patients with proximal DVT had a longer hospital length of stay (22 days [IQR 11-60] vs. 14 days [7-23], p = 0.03) and spent more time on mechanical ventilation (10 days (3.3-57) vs. 6 days (3-12), p = 0.053) than patients without DVT. Patient mortality was not affected by the presence of DVT (52% vs. 38.3%, p = 0.29).

Conclusions

Routine thromboprophylaxis is not used in our institution and the prevalence and incidence proportion of proximal DVT in Asian medical critical care patients were both substantial. Patients with older age, female gender, an intravenous femoral catheter, and the absence of platelet transfusion all had a higher chance of developing proximal DVT.

Multi-organ point-of-care ultrasound for COVID-19 (PoCUS4COVID): international expert consensus

COVID-19 has caused great devastation in the past year. Multi-organ point-of-care ultrasound (PoCUS) including lung ultrasound (LUS) and focused cardiac ultrasound (FoCUS) as a clinical adjunct has played a significant role in triaging, diagnosis and medical management of COVID-19 patients. The expert panel from 27 countries and 6 continents with considerable experience of direct application of PoCUS on COVID-19 patients presents evidence-based consensus using GRADE methodology for the quality of evidence and an expedited, modified-Delphi process for the strength of expert consensus. The use of ultrasound is suggested in many clinical situations related to respiratory, cardiovascular and thromboembolic aspects of COVID-19, comparing well with other imaging modalities. The limitations due to insufficient data are highlighted as opportunities for future research.

Cardiovascular ultrasonography detection of embolic sources in trauma

Venous thromboembolism (deep vein thrombosis and pulmonary embolism) and bone cement implantation syndrome are major sources of embolic events in trauma patients. In these patients, embolic events due to venous thromboembolism and bone cement implantation syndrome have been detected with cardiac and vascular ultrasonography in the emergency setting, during the perioperative period, and in the intensive care unit. This article discusses the ultrasonography modalities and imaging findings of embolic events related to venous thromboembolism and bone cement implantation syndrome. The aim is to present a short review with exceptional illustrations that can enable physicians to identify sources of emboli in trauma patients with cardiovascular ultrasonography.

Postoperative Massive Pulmonary Embolism Due to Superficial Vein Thrombosis of the Upper Limb

It is well known that deep vein thrombosis of the upper extremities is linked to high morbidity/mortality, resulting in 12-20% of all documented pulmonary embolism; however, there are few data about thromboembolism originating from a vein and/or a branch of a superficial vein of the upper extremities. Pulmonary embolism secondary to upper limb superficial vein thrombosis (not combined with upper extremities deep vein thrombosis) is a very rare clinical manifestation with few cases reported in the literature. We report a rare case of thrombophlebitis in departure from a superficial branch of the cephalic vein of the right arm, complicated by cardiac arrest secondary to a massive pulmonary embolism in a patient who underwent major surgery for ovarian cancer. We discuss on the numerous thrombotic risk factors, triggering a cascade of reactions and resulting in a potential fatal clinical manifestation.

Point-of-Care Ultrasound for a Deep Venous Thrombosis

Patients presenting to the emergency department with lower extremity symptoms suggestive of venous thromboembolic disease require a diagnostic evaluation. Although contrast venography was the diagnostic standard, this has largely been replaced by duplex ultrasound as the first-line imaging modality. This review presents a summary of the literature on the evolution and performance of B-mode point-of-care compression ultrasound as an alternative to duplex ultrasound evaluation. The 2-point compression and 2-region compression techniques are described. The limitations of point-of-care ultrasound of the lower extremity as a diagnostic modality for this disease entity, the role of a D-dimer assay in the emergency department evaluation and future directions for this diagnostic modality are discussed.

Ultrasound-based imaging in neurocritical care patients: a review of clinical applications

OBJECTIVE

To analyze the diagnostic, monitoring, and procedural applications of ultrasound (US) imaging in neurocritical care (NCC) patients.

METHOD

US imaging has been extensively validated in various subset of critically ill patients, but not specifically in the NCC population. We reviewed the clinical applications of US imaging for heart, vascular, brain, and lung evaluation and for possible procedural uses in NCC patients. Major neurosurgical books, journals, testimonials, authors' personal experience, and scientific databases were analyzed.

RESULTS

Cardiac US imaging provides accurate information at NCC arrival to stratify risk factors, including presence of atrial septal defect/patent formen ovale, abnormal ventricular function, or pericardial effusion, and to monitor cardiac anatomy and function during the NCC stay for guiding goal-directed therapy. Vascular US in NCC patients has three especially relevant indications: to screen anatomy and flow in extracranial supra-aortic arteries, to diagnose deep vein thrombosis, and to optimize the safety of central venous catheterization. Brain US has important clinical applications in the NCC, including transcranial Doppler and emerging techniques for cerebral blood flow evaluation with contrast-enhanced US imaging. Lung US, as demonstrated in other intensive care unit patients, provides accurate diagnosis of anatomical and functional abnormalities and enables diagnosis of pleural effusion, pneumothorax, lung consolidation, pulmonary abscess and interstitial-alveolar syndrome, and lung recruitment/derecruitment. US imaging can effectively guide percutaneous tracheostomy.

CONCLUSION

In conclusion, US imaging is an important diagnostic tool that provides real-time information at the bedside to stratify risk, monitor for complications, and guide invasive procedures in NCC patients.

A successful free fibula transfer in the patient with chronic peroneal vein thrombosis

Despite the rare incidence, occult chronic thrombosis of peroneal veins of the fibula graft during the flap harvest presents a challenge to produce a successful reconstruction. In this article, we present a case of a 54-year-old man with chronic thrombosis of peroneal veins found during the harvest of the free fibula osteocutaneous flap for reconstruction of the mandible defect after tumor ablation. With near-total obliteration of the lumens, a small lumen with residual blood outflow was identified under microscopic magnification. A successful flap transfer was made possible by using the recanalized lumen around the chronic thrombus of the vein for microanastomosis. The pathological analysis of the vein revealed that the recanalized lumens and the endothelial cells-specific CD31 immunohistochemical stain highlighted the endothelium of regenerative lumen around the chronic thrombus. The abundant deposition of thick collagen fibers also suggested a chronic nature of the thrombus. However, although a successful microsurgical free osteocutaneous flap transfer might be possible in the patient with lower-limb chronic peroneal vein thrombosis, a careful preoperative evaluation with imaging study is recommended for high-risk patients.

[Prevention of venous thromboembolic disease in the critical patient: an assessment of clinical practice in the Community of Madrid]

OBJECTIVE

To analyze measures referred to venous thromboembolic prophylaxis in critically ill patients.

DESIGN

An epidemiological, cross-sectional (prevalence cut), multicenter study was performed using an electronic survey. Comparison of results with quality indexes of the Spanish Society of Intensive Care Medicine, the American College of Chest Physician guidelines and international studies.

SETTING

Intensive Care Units (ICUs) in the Community of Madrid (Spain).

PATIENTS

All patients admitted to the ICU on the day of the survey.

VARIABLES OF INTEREST

General aspects of venous thromboembolic prophylaxis and protocols used (risk stratification and ultrasound screening). A descriptive analysis was performed, continuous data being expressed as the mean or median, and categorical data as percentages.

RESULTS

A total of 234 patients in 18 ICUs were included. Eighteen percent (42/234) received no prophylaxis, and 55% had no contraindication to pharmacological prophylaxis. Of the 192 patients receiving prophylaxis, 84% received pharmacological prophylaxis, 14% mechanical prophylaxis and 2% combined prophylaxis. Low molecular weight heparin was the only pharmacological prophylaxis used, with a majority use of enoxaparin (17 of 18 ICUs). In patients with mechanical prophylaxis (31/192), antiembolic stockings were the most commonly used option (58%). Pharmacological prophylaxis contraindications were reported in 20% of the patients (46/234), the most frequent cause being thrombocytopenia (28% of the cases). Fifty percent of the ICUs used no specific venous thromboembolic prophylaxis protocol.

CONCLUSIONS

Pharmacological prophylaxis with low molecular weight heparin was the most frequently used venous thromboembolic prophylactic measure. In patients with contraindications to pharmacological prophylaxis, mechanical measures were little used. The use of combined prophylaxis was anecdotal. Many of our ICUs lack specific prophylaxis protocols.

Bedside ultrasound in resuscitation and the rapid ultrasound in shock protocol

Assessment of hemodynamic status in a shock state remains a challenging issue in Emergency Medicine and Critical Care. As the use of invasive hemodynamic monitoring declines, bedside-focused ultrasound has become a valuable tool in the evaluation and management of patients in shock. No longer a means to simply evaluate organ anatomy, ultrasound has expanded to become a rapid and noninvasive method for the assessment of patient physiology. Clinicians caring for critical patients should strongly consider integrating ultrasound into their resuscitation pathways.

Emergency department diagnosis of upper extremity deep venous thrombosis using bedside ultrasonography

A 27-year-old man presents to the emergency department with a 1-day history of severe right upper extremity pain and swelling. The patient's status is post open reduction internal fixation for a left tibial plateau fracture, which was complicated by methicillin-sensitive Staphylococcus aureus osteomyelitis. A peripherally inserted central catheter (PICC) line was subsequently placed for intravenous antibiotic therapy. Emergency department bedside ultrasound examination of both the right axillary vein and subclavian vein near the PICC line tip revealed deep venous thrombosis of both veins. Bedside upper extremity vascular ultrasonography can assist in the rapid diagnosis of upper extremity deep venous thrombosis in the emergency department.

Imaging presentation of venous thrombosis in patients with cancer

OBJECTIVE

The purpose of this article is to review the imaging of venous thrombosis in patients with cancer.

CONCLUSION

Multiple imaging techniques have the capacity to display thrombosis accurately. The optimal choice is dictated by the location and duration of symptoms and by the availability of imaging techniques. Peripheral and superficial thrombi are best managed with ultrasound, whereas central thrombi require CT or MRI. If CT and MRI are contraindicated, flow studies are appropriate. FDG PET/CT appropriately shows venous thrombosis and might play a prominent role in the future.

The RUSH exam: Rapid Ultrasound in SHock in the evaluation of the critically lll

The RUSH exam (Rapid Ultrasound in SHock examination), presented in this article, represents a comprehensive algorithm for the integration of bedside ultrasound into the care of the patient in shock. By focusing on a stepwise evaluation of the shock patient defined here as "Pump, Tank, and Pipes," clinicians will gain crucial anatomic and physiologic data to better care for these patients.

Whole-body ultrasound in the intensive care unit: a new role for an aged technique

Management of critically ill patients requires rapid and safe diagnostic techniques. Ultrasonography has become an indispensable tool that supplements physical examination in the intensive care unit. It enables early recognition of neurological emergencies, assists the diagnosis of abdominal and lung pathologies, and provides real-time information on the cardiac performance of critically ill patients. Furthermore, it detects possible infectious sites and renders therapeutic invasive procedures more convenient and less complicated. Whole-body ultrasound in the hands of adequately trained intensivists has the ability to reinvigorate the physical examination, without subjecting the patient to excessive irradiation and the risks of transport.

Ultrasound in the surgical intensive care unit

PURPOSE OF REVIEW

Critically ill patients are subjected to a variety of diagnostic and therapeutic procedures. It is desirable to make these interventions as timely, safe, and effective as possible. Bedside ultrasound and echocardiography are tools that allow for diagnosis of many conditions, without subjecting the patient to radiation, dye, and the risks of transport. In addition, ultrasound guidance of procedures may improve safety and efficacy. This review analyzes the literature on ultrasound and echocardiography use in the ICU.

RECENT FINDINGS

There is evidence supporting the use of bedside echocardiography and ultrasound for the diagnosis of chest, abdominal, and other pathologic conditions in the ICU. There is also evidence to support ultrasound guidance of vascular access and other procedures. There are multiple reports of novel uses of bedside echocardiography and ultrasound in the ICU.

SUMMARY

There is substantial literature supporting ultrasound and bedside limited echocardiography in the critical care setting. In addition, there are frequent reports of new applications for these technologies in the literature. The role of ultrasound and bedside limited echocardiography in the critical care setting is likely to expand in the future and become a part of daily care in every surgical intensive care unit.