Screening For Deep Venous Thrombosis Research Articles

Rapid-Inflation Intermittent Pneumatic Compression for Prevention of Deep Venous Thrombosis

Current treatment regimens that are designed to prevent deep venous thrombosis in patients undergoing orthopaedic procedures rely predominantly on drug prophylaxis alone. The purpose of this randomized clinical study was to evaluate the effectiveness of a mechanical adjunct to chemoprophylaxis that involves intermittent compression of the legs. During a twenty-two month period, 1803 patients undergoing a variety of orthopaedic procedures were prospectively randomized to receive either chemoprophylaxis alone or a combination of chemoprophylaxis and mechanical prophylaxis. Nine hundred and two patients were managed with low-molecular-weight heparin alone, and 901 were managed with low-molecular-weight heparin and intermittent pneumatic compression of the calves for varying time periods. Twenty-four percent of the patients underwent total hip or knee joint replacement. Screening for deep venous thrombosis was performed on the day of discharge with duplex-color-coded ultrasound. In the chemoprophylaxis-only group, fifteen patients (1.7%) were diagnosed with a deep venous thrombosis; three thromboses were symptomatic. In the chemoprophylaxis plus intermittent pneumatic compression group, four patients (0.4%) were diagnosed with deep venous thrombosis; one thrombosis was symptomatic. The difference between the groups with regard to the prevalence of deep venous thrombosis was significant (p = 0.007). In the chemoprophylaxis plus intermittent pneumatic compression group, no deep venous thromboses were found in patients who received more than six hours of intermittent pneumatic compression daily. Venous thrombosis prophylaxis with low-molecular-weight heparin augmented with a device that delivers rapid-inflation intermittent pneumatic compression to the calves was found to be significantly more effective for preventing deep venous thrombosis when compared with a treatment regimen that involved low-molecular-weight heparin alone.

Accuracy of compression ultrasound in screening for deep venous thrombosis in acutely ill medical patients

The value of vein ultrasonography for diagnosis of symptomatic deep vein thrombosis (DVT) is widely accepted. We are unaware of published data comparing ultrasonography with the "gold standard" of venography for DVT diagnosis in asymptomatic persons in the patient group of acutely ill medical patients. It was the objective of this study to evaluate sensitivity and specificity of compression ultrasound (CUS) examinations in the diagnosis of proximal and distal DVT in acutely ill medical patients [with congestive heart failure (NYHA class III and IV), exacerbations of respiratory disease, infectious disease, and inflammatory diseases] considered to be at moderate risk of venous thromboembolism (VTE). CUS examination was performed prior to ascending venography on day 6-15 of the hospital stay. Both investigations were done on the same day, each interpreted without knowledge of the other's result. Proximal and calf veins were separately evaluated. Technically satisfactory venography was obtained in 160 patients. In 12 of 160 patients (7.5%, 95% CI=[4.0%-12.7%]), venography confirmed the presence of DVT, all of which was asymptomatic. Proximal DVT was detected in five patients (3.1%, 95% CI=[1.0%-7.1%]) and distal DVT in seven patients (4.4%, 95% CI=[1.8%-8.8%]). CUS of proximal veins was technically satisfactory in all 160 patients and CUS of distal veins in 150 patients. In three of five patients with venographically proven proximal DVT, the diagnosis was confirmed by CUS (sensitivity 60%, 95%CI=[23%-88%]). In one patient, the CUS was false positive (specificity 99.4%, 95%CI=[96%-99%]). Positive and negative predictive values (PPV and NPV) of CUS in the diagnosis of proximal DVT were 75% (95%CI=[30%-95%]) and 98% (95% CI=[95%-99%]), respectively. In two of seven patients with venographically proven calf DVT, the diagnosis was confirmed by CUS (sensitivity 28.6%, 95%CI=[8%-64%]) and in two patients, CUS was false positive (specificity 98.6, 95%CI=[95%-99%]). PPV and NPV of CUS in diagnosis of distal DVT were 50% (95%CI=[15-85%]) and 96% (95% CI=[92%-98%]), respectively. In conclusion, CUS underestimates the incidence of proximal and distal DVT compared to contrast venography in acutely ill medical patients without thrombosis symptoms.

Utility of Once‐Daily Dose of Low‐Molecular‐Weight Heparin to Prevent Venous Thromboembolism in Multisystem Trauma Patients

Venous thromboembolism is a preventable cause of death in the severely injured patient. Low-molecular-weight heparins (LMWHs) have been recommended as effective, safe prophylactic agents. However, LMWH use remains controversial in patients at risk for bleeding, those with traumatic brain injury, and those undergoing multiple invasive or operative procedures. We hypothesized that a protocol utilizing once-daily LMWH prophylaxis in high-risk trauma patients, regardless of the need for invasive procedures, is feasible, safe, and effective. From August 1998 to August 2000, all patients admitted to our American College of Surgeons-verified Level I trauma facility following injury were evaluated for deep venous thrombosis (DVT) risk and prospectively followed. Patients at high risk for DVT, including those with stable intracranial injuries, were placed on our institutional protocol and prospectively followed. Patients on the protocol received daily injections of the LMWH, dalteparin; DVT screening was performed with duplex ultrasonography within 48 hours of admission and after 7 to 10 days after injury. Regimen compliance, bleeding complications, DVT rates, and pulmonary embolus (PE) rates were analyzed. During the 2-year study period, 6247 trauma patients were admitted; 743 were considered at high risk for DVT. Most of the patients were men (72%), with a mean age of 38.7 years (range 15-89 years) and a mean injury severity score (ISS) of 19.5. Compliance with the daily regimen was maintained in 74% of patients. DVT was detected in 3.9% and PE in 0.8%. The wound complications rate was 2.7%, and the need for unexplained transfusions was 3%. There were no exacerbations of head injury following dalteparin initiation due to bleeding. There were 16 patient deaths; none was caused by PE or late hemorrhage. Once-daily dosing of prophylactic LMWH dalteparin is feasible, safe, and effective in high-risk trauma patients. Our protocol allows one to "operate through" systemic prophylaxis and ensures timely prophylaxis for brain-injured and multisystem trauma patients.

Deep Venous Thrombosis Management Following Traumatic Brain Injury

To determine national patterns of screening, prophylaxis, and treatment of deep venous thrombosis (DVT) following traumatic brain injury (TBI) within the Traumatic Brain Injury Model Systems (TBIMS). e-mail survey instrument. Multicenter Regional TBIMS. Fifteen of the 16 rehabilitation centers within the TBIMS responded to the survey (94% response rate). Approximately half of these centers routinely screen to detect subclinical DVTs (56% venous duplex ultrasonography, 12% plasma D-dimer) on admission to inpatient rehabilitation. Fifty-six percent of respondents use anticoagulation prophylactically, while 69% use mechanical means for DVT prophylaxis. Eighty fatal pulmonary emboli were reported for TBI patients in 189 practice-years, corresponding to 0.42 fatalities per year of practice. No consensus exists regarding the optimal methods for screening, prevention, or treatment of DVT in TBI patients in the acute rehabilitation setting of the TBIMS. The number of fatal pulmonary emboli reported among these centers emphasizes the need to develop evidence-based clinical practice guidelines for the prevention and treatment of venous thromboembolism in this patient population.

Is Screening for Deep Venous Thrombosis in Aneurysmal Subarachnoid Hemorrhage Patients Cost Effective?

Is Screening for Deep Venous Thrombosis in Aneurysmal Subarachnoid Hemorrhage Patients Cost Effective?

Is Screening for Deep Venous Thrombosis in Aneurysmal Subarachnoid Hemorrhage Patients Cost Effective?

Neurosurgery: August 2006 - Volume 59 - Issue 2 - p 472 doi: 10.1227/01.NEU.0000309905.75057.08

Screening for Deep Venous Thrombosis (DVT) in Asymptomatic Patients. A Comparison Between Digital Photoplethysmography (D-PPG) and Duplex Sonography

Screening for Deep Venous Thrombosis (DVT) in Asymptomatic Patients. A Comparison Between Digital Photoplethysmography (D-PPG) and Duplex Sonography

Deep Venous Thrombosis in Patients With Acute Pulmonary Embolism: Prevalence, Risk Factors, and Clinical Significance

To determine the prevalence of lower-limb deep venous thrombosis (DVT) that can be detected by compression ultrasonography (CUS) in patients with symptomatic pulmonary embolism (PE) diagnosed with spiral CT pulmonary angiography (CTPA); and to explore the risk factors for positive CUS results and the prognostic significance of such findings. Post hoc analysis of data from a prospective multicenter outcome study of 1,041 patients with clinically suspected non-severe PE. All patients underwent CTPA and CUS within 24 h of enrollment and were followed up for 3 months. Among the 290 patients with positive CT findings, CUS was diagnostic in 281 patients who constitute the study population. Mean age +/- SD was 64.3 +/- 17.7 years; 128 patients (44.8%) were men. DVT signs or symptoms were present in 90 patients (32%). CUS detected DVT in 169 patients (60.1%; 95% confidence interval [CI], 54.1 to 65.9%), including 127 patients (45.2%; 95% CI, 39.3 to 51.2%) with proximal DVT. Sensitivity and specificity of DVT symptoms for CUS-detectable DVT were 43% and 85%, respectively. Multivariate analysis showed that an age > or = 70 years (odds ratio [OR], 1.90; 95% CI, 1.14 to 3.17) and the presence of DVT signs or symptoms (OR, 4.12; 95% CI, 2.24 to 7.55) were independent risk factors for positive CUS results. DVT symptoms (OR, 4.78; 95% CI, 2.75 to 8.33) and a history of venous thromboembolism (OR, 2.59; 95% CI, 1.46 to 4.62) were independent risk factors for proximal DVT. The 3-month risk of recurrent thromboembolic event or death was not significantly different among patients with and without DVT (6.5% vs 2.7%, p = 0.15). These results do not support screening for DVT in patients with CTPA-proven symptomatic PE; however, they suggest that CUS might prove especially efficient and safe as a frontline test in elderly patients with suspected PE. Further studies are needed before these conclusions can be translated into clinical recommendations.

5:37 55. The incidence of pelvic DVT following combined anterior/posterior reconstruction for adult spinal deformity: a prospective cohort study using magnetic resonance venography

BACKGROUND CONTEXT: While the risk of thromboembolic disease (TED) following spine operations is generally considered to be low, little study has focused on the potentially higher risk of TED after combined anterior/posterior reconstructions. Conventional screening for deep venous thrombosis (DVT) cannot adequately detect pelvic DVT. Magnetic resonance venography (MRV) is the most effective means of detecting pelvic DVT but has never been used in spine patients.

Deep Venous Thrombosis and Pulmonary Embolism in Trauma Patients: An Overstatement of the Problem?

Deep venous thrombosis (DVT) and pulmonary embolism (PE) affect high-risk trauma patients (HRTP). Accurate incidence and clinical importance of DVT and PE in HRPT may be overstated. We performed a ten-year retrospective analysis of HRTP of the Pennsylvania Trauma Outcome Study. High-risk factors (HRF) included pelvic fracture (PFx), lower extremity fracture (LEFx), severe head injury (CHI) (AIS - head > or =3), and spinal cord injury. HRF alone or in combination, age, Injury Severity Score (ISS), and Glasgow Coma Score (GCS) were examined for association with DVT/PE. A total of 73,419 HRTP were included: 1377 (1.9%) had DVT, 365 (0.5%) had PE. The incidence of DVT in level I trauma centers was 2.2 per cent and was 1.5 per cent in level II centers. The lowest incidence of DVT was 1.3 per cent for isolated LEFx; highest was 5.4% for combined PFx, LEFx, and CHI. Variables associated with DVT included age, ISS, and GCS (all P < 0.001). In logistic regression analysis, only ISS was consistently predictive for DVT and PE. Though increased during the past decade, the overall incidence of DVT in HRTP remains below 3 per cent. Only the combination of multiple injuries or an ISS >30 result in DVT incidence of > or =5 per cent. We believe that current guidelines for screening for DVT may need to be reevaluated.

Deep venous thrombosis: Comparison of indirect multidetector CT venography and sonography of lower extremities in 26 patients

Objective To compare the accuracy of indirect mutidetector row computed tomographic (MDCT) venography with lower extremity venous sonography for the diagnosis of femoropopliteal deep venous thrombosis (DVT), and to determine the frequency and location of DVT at MDCT venography. Materials and methods Twenty-six consecutive patients suspected of having pulmonary embolism (PE) underwent both combined MDCT venography and MDCT pulmonary angiography and lower extremity venous sonography. Indirect MDCT venography was acquired from the upper calves to the mid-abdomen following MDCT pulmonary angiography. The CT venographic findings were compared with those of sonography for the diagnosis of femoropopliteal DVT. All CT scans were also reviewed for the frequency and location of DVT. Results Indirect MDCT venography disclosed DVT in 19 patients, and 12 of whom also had PE. Seventeen patients with thrombosis in the femoropopliteal veins were identified in both indirect MDCT venography and sonography. The sensitivity and specificity of indirect MDCT venography for femoropopliteal DVT, as compared with sonography, were both 100%. In one patient DVT in the superficial femoral vein was detected using only indirect MDCT venography. MDCT venography also showed superior extension of femoropopliteal DVT to the inferior vena cava and iliac veins in four patients and thrombosis isolated to the inferior vena cava and common iliac vein thrombosis in one patient. Conclusions Indirect MDCT venography is as accurate as sonography in the diagnosis of femoropopliteal DVT. MDCT venography can further reveal thrombus in large pelvis veins and the inferior vena cava, an important advantage over sonographic screening for DVT.

Screening for deep venous thrombosis in children undergoing scoliosis surgery

Kaabachi, O.1; Aloui, N.2; Toumi, N. H.3; Jelel, C.1; Nessib, M. N.1; Ben Ghachem, M.1 Author Information

Sonography of polyethylene liners used in total knee arthroplasty.

We investigated the ability of sonography to reveal the polyethylene liner used in total knee arthroplasty with the hopes of establishing a possible relationship between the sonographic measurement of the actual thickness of the polyethylene liner and the estimated thickness based on conventional radiography. Twenty-four consecutive patients who were referred for Doppler screening for deep venous thrombosis after total knee arthroplasty were evaluated. The polyethylene liner was identified on sonography, and three measurements were obtained from four locations: anteromedial joint line (just medial to the midline incision), along the medial joint line, anterolateral joint line (just lateral to the midline incision), and along the lateral joint line. These sonographic measurements were compared with radiographic measurements of the radiolucent polyethylene liner and with the manufacturers' stated size of the polyethylene liner. Linear regression analyses were then performed. The polyethylene liner is seen on sonography as a strong linear echogenic interface with posterior acoustic shadowing. Linear regression analyses showed a high correlation (r = 0.8) between the sonographic measurements and the radiographic measurements. A relatively poor correlation (r = 0.2) was noted between the manufacturers' stated size of the liner and the sonographic measurements. We found that the polyethylene liner used in total knee arthroplasty can be clearly identified during sonographic evaluation of the knee. We also found a high correlation between the longitudinal measurement of the polyethylene liner with the thickness of the radiolucent polyethylene as measured on conventional radiographs. We propose that sonography could potentially be a useful noninvasive imaging modality to screen for subtle cases of polyethylene wear.

Screening for deep venous thrombosis after total hip and knee arthroplasty

Screening for deep venous thrombosis after total hip and knee arthroplasty

Surveillance for venous thromboembolic disease after total knee arthroplasty.

The value of deep venous thrombosis screening after total knee arthroplasty is controversial. The purpose of the current study was to examine the value of routine surveillance for venous thrombosis after total knee arthroplasty done with modern operative and perioperative treatment. Computerized search engines were used to identify papers published between 1985 and July 2000 relevant to the purpose of the study. Papers that met the inclusion criteria for review were categorized as follows: the frequency of deep venous thrombosis; the natural history of deep venous thrombosis; the accuracy of screening methods for venous thrombosis; and efficacy of screening in reducing morbidity attributable to venous thromboembolism after total knee arthroplasty. Several studies have shown a low complication rate related to venous thromboembolic disease when compression ultrasound is used for screening as part of a clinical algorithm after knee arthroplasty. However, the only large prospective randomized trial evaluating ultrasound screening failed to show a reduction in morbidity with a surveillance protocol. The benefits of surveillance depend on factors specific to each surgeon's practice including the type and duration of venous prophylaxis, the rate of symptomatic and asymptomatic thromboembolic disease associated with that protocol, and the accuracy of screening tests used for surveillance.

Catheter-related upper extremity deep venous thrombosis in cancer patients: a prospective study based on Doppler US.

This prospective study extending for more than 3 years had two objectives: (a) to use Doppler ultrasonography (US) to estimate the incidence of asymptomatic catheter-related upper extremity deep venous thrombosis (DVT) in a large population and (b) to study the effect of the catheter position as an individual risk factor for catheter-related DVT. Between October 1995 and June 1998, a total of 145 patients who had oropharyngeal tract cancer and who were fitted with the same totally implantable central venous catheters (CVCs) were included in the study. Follow-up included (a) estimation of the position of each catheter tip on a chest radiograph obtained immediately after surgery and (b) regular monthly Doppler US screening for catheter-related DVT. Seventeen patients developed catheter-related DVT; 13 of them were asymptomatic. The mean interval between CVC implantation and detection of thrombosis was 42.2 days. Correct positioning of the distal catheter tip was associated with a significantly lower rate of catheter-related DVT. Only five of 87 patients with a correctly positioned distal catheter tip (ie, either in the superior vena cava or at the junction between the right atrium and the superior vena cava) developed thrombosis, compared with 12 of 26 patients with a misplaced catheter (P <.001). The side on which the CVC was implanted did not influence the catheter-related DVT rate. The rate of asymptomatic catheter-related DVT is high and could be lowered with correct initial CVC positioning.

Attitudes of Orthopaedic Trauma Surgeons Regarding Current Controversies in the Management of Pelvic and Acetabular Fractures

A closed-ended questionnaire was mailed to all 363 active members of the Orthopaedic Trauma Association. It directed, toward practicing pelvic and acetabular surgeons, questions pertaining to practice demographics and preferred methods for detection and prevention of deep venous thrombosis (DVT), nerve injury, and heterotopic ossification (HO). Questionnaires were received from 226 surgeons (62 percent). Of the surgeons who responded, 181 (80 percent) perform pelvic-fracture and acetabular-fracture surgery; only questionnaires from this group were analyzed. Standard statistical methods were used to perform both univariate and multivariate analyses. Preoperative DVT screening was performed by 48 percent of the surgeons; ultrasound was the most commonly used modality (82 percent). Preoperative DVT prophylaxis was administered by 88 percent of those surveyed; the majority (78 percent) used sequential compression devices. Postoperative prophylaxis was used by 99 percent; the most commonly used modality was sequential compression devices. Analysis suggests that fellowship-trained surgeons and surgeons in practice for fewer than twenty years are more likely to use preoperative DVT prophylaxis. HO prophylaxis was administered by 88 percent; the most commonly used modality was indomethacin. Intraoperative nerve monitoring was performed by only 15 percent of the respondents. Most surgeons employed prophylactic measures to prevent DVT and HO. The wide variation in type of prophylaxis and reasons for use suggests that controversy will continue, and a standard of care for these conditions has yet to be defined. Very few surgeons use intraoperative nerve monitoring routinely.

A meta-analysis of thromboembolic prophylaxis in total knee arthroplasty

Deep venous thrombosis (DVT) is common in total knee arthroplasty (TKA). Because of the rarity of the most serious outcomes, most randomized controlled trials lack the power to analyze these outcomes. A meta-analysis was performed for agents used in DVT prophylaxis in TKA employing a Medline literature search. Study inclusion criteria were randomized controlled trials comparing prophylactic agents in elective TKA with mandatory screening for DVT by venography. Fourteen studies (3,482 patients) met inclusion criteria. For total DVT, all agents except dextran and aspirin protected significantly better than placebo (P <.0001). For proximal DVT rates, low-molecular-weight heparin was significantly better than warfarin (P =.0002). There was a trend that aspirin was better than warfarin (P =.0106). No significant difference was found for symptomatic pulmonary embolism, fatal pulmonary embolism, major hemorrhage, or total mortality.

Potential risk factors for deep venous thrombosis in burn patients.

Risk factors and prophylaxis for prevention of deep venous thrombosis (DVT) and pulmonary embolism remain controversial in burn patients. From January 1996 through June 1999, we reviewed all adult burn patients admitted to our burn center with the in-hospital diagnosis of DVT and assessed each affected patient for DVT risk factors. There were 8 symptomatic DVTs and 2 pulmonary embolisms detected in 327 adult burn patients (2.4% incidence). No DVT patient had the risk factors of morbid obesity, previous DVT, congestive heart failure, or neoplastic disease. One patient was older than 65 years. All of the DVTs occurred in veins draining a burned extremity. Seven of 8 patients had burn wound infections as complications. Burns on the extremity developing the DVT as well as the diagnosis of a burn wound infection were significant risk factors for DVT formation. These findings prompt us to consider routine screening for DVT in burn patients with these risk factors.

Prevention and diagnosis of venous thromboembolism in critically ill patients: a Canadian survey.

Venous thromboembolism (VTE) confers considerable morbidity and mortality in hospitalized patients, although few studies have focused on the critically ill population. The objective of this study was to understand current approaches to the prevention and diagnosis of deep venous thrombosis (DVT) and pulmonary embolism (PE) among patients in the intensive care unit (ICU). Mailed self-administered survey of ICU Directors in Canadian university affiliated hospitals. Of 29 ICU Directors approached, 29 (100%) participated, representing 44 ICUs and 681 ICU beds across Canada. VTE prophylaxis is primarily determined by individual ICU clinicians (20/29, 69.0%) or with a hematology consultation for challenging patients (9/29, 31.0%). Decisions are usually made on a case-by-case basis (18/29, 62.1%) rather than by preprinted orders (5/29, 17.2%), institutional policies (6/29, 20.7%) or formal practice guidelines (2/29, 6.9%). Unfractionated heparin is the predominant VTE prophylactic strategy (29/29, 100.0%) whereas low molecular weight heparin is used less often, primarily for trauma and orthopedic patients. Use of pneumatic compression devices and thromboembolic stockings is variable. Systematic screening for DVT with lower limb ultrasound once or twice weekly was reported by some ICU Directors (7/29, 24.1%) for specific populations. Ultrasound is the most common diagnostic test for DVT; the reference standard of venography is rarely used. Spiral computed tomography chest scans and ventilation-perfusion scans are used more often than pulmonary angiograms for the diagnosis of PE. ICU Directors recommend further studies in the critically ill population to determine the test properties and risk:benefit ratio of VTE investigations, and the most cost-effective methods of prophylaxis in medical-surgical ICU patients. Unfractionated subcutaneous heparin is the predominant VTE prophylaxis strategy for critically ill patients, although low molecular weight heparin is prescribed for trauma and orthopedic patients. DVT is most often diagnosed by lower limb ultrasound; however, several different tests are used to diagnose PE. Fundamental research in critically ill patients is needed to help make practice evidence-based.