Screening For Deep Venous Thrombosis Research Articles

Dépistage clinique de la thrombose veineuse profonde après prothèse de hanche et de genou. Proposition d’un score de prédiction pour guider l’indication de l’échographie-Doppler veineux

To assess the most accurate clinical signs and clinical scoring for selecting patients who could benefit from duplex sonography screening of deep venous thrombosis (DVT) after total hip replacement (THR) and total knee replacement (TKR). Four hundred and eighty consecutive patients with THR or TKR were included. Post-operative physical examination and venous duplex sonography (day 6-10) were performed in all of them. DVT was diagnosed in presence of at least 3mm thick and 3 cm long incomplete venous compressibility. Clinical prediction scores were built from clinical parameters, which were significantly associated with DVT in univariate analysis, one of them weighted from logistic multivariate regression coefficients. Recent DVT was diagnosed in 74 patients (15.7%) (29.6% after TKR and 8.4% after THR). There was no isolated proximal DVT and extensive DVTs were very rare (TKR 1.2% vs. THR 1%). Two TKR patients developed pulmonary embolism (1.2%). One died (0.6%). Univariate analysis showed significant association between provoked localized limb pain, pitting edema and difference in calf circumference (DCC), and DVT (P<0.0001). DCC> 3 cm was significantly associated with DVT (32.4% vs. 16.6%, OR 2.4 [1.3-4.2] ; P=0.001). In multivariate analysis the only two clinical manifestations independently associated with DVT were provoked localized limb pain (adjusted OR 2.3 [1.3-4.1] ; P<0.01) and DCC> 3 cm (adjusted OR 2.0 [1.1-3.8] ; P=0.04). A clinical score value greater or equal to 4 was associated with a risk of DVT of 34%, and a value<4 with a risk of 9%. After THR or TKR, DCC> 3 cm or a clinical risk score greater or equal to 4 could be used as an accurate and easy clinical test for assessing the need for further DVT screening by sonography.

Incidence of Pulmonary Embolus in Combat Casualties With Extremity Amputations and Fractures

The objective of this retrospective study was to determine the incidence of pulmonary embolism (PE) in casualties of wartime extremity wounds and specifically in casualties with a trauma-associated amputation. Records of all combat-wounded evacuated and admitted between March 1, 2003, and December 31, 2007, were retrospectively reviewed. Continuous and categorical variables were studied with the Student's t test, Fisher's exact test or χ² test; multivariate analysis was performed using a stepwise regression logistic model. A total of 1,213 records were reviewed; 263 casualties met the inclusion criteria. One hundred three (41.5%) had amputations and 145 (58.5%) had long-bone fractures not requiring amputation. The observed rate of PE in these 263 casualties was 5.7%. More casualties with amputations, 10 (3.7%), developed PE than those with long-bone fractures in the absence of amputation, 5 (1.9%) (p = 0.045). Casualties with bilateral lower extremity trauma-associated amputations had a significantly higher incidence of PE compared with those sustaining a single amputation (p = 0.023), and the presence of bilateral lower extremity amputations was an independent risk factor for development of a PE (p = 0.007, odds ratio 5.9) (univariate and multivariate analysis, respectively). The cumulative incidence of PE was 5.7%. The incidence of PE is significantly higher with trauma-associated amputation than with extremity long-bone fracture without amputation. Bilateral amputations, multiple long-bone fractures, and pelvic fractures are independent risk factors for the development of PE. The use of aggressive prophylaxis, deep venous thrombosis screening with ultrasound, and use of prophylactic inferior vena cava filters should be considered in this patient population.

Duplex ultrasound screening detects high rates of deep vein thromboses in critically ill trauma patients

American College of Chest Physician (ACCP) guidelines stratify deep venous thrombosis (DVT) risk in trauma patients based on injury pattern and pharmacologic prophylaxis. Screening is only recommended for patients with high-risk injuries who are unable to receive pharmacologic prophylaxis. However, the prevalence of lower extremity DVT (LEDVT) in trauma patients may be higher than reported in previous studies as many studies on DVT screening have not investigated calf vein DVTs (CVDVT) and have not exclusively targeted critically ill patients. Given that current ACCP guidelines recommend treatment of CVDVTs, we investigated the efficacy of duplex ultrasound (DUS) screening in critically ill trauma patients for all LEDVTs, including CVDVT, regardless of injury pattern, risk factors, or pharmacologic prophylaxis. Medical records of 264 intensive care unit trauma patients who received DUS screening for LEDVT were retrospectively examined for the presence of injuries conferring high risk for LEDVT, patient specific DVT risk factors, and low molecular weight heparin (LMWH) prophylaxis. Forty (15.2%) patients had LEDVTs found on DUS screening, 24 (60%) were CVDVT, and 30% of all DVTs were diagnosed within 1 week of admission. Patients without high-risk injuries receiving LMWH had a 13.5% DVT rate, which did not differ significantly from the 19.7% DVT rate in high-risk injury patients not receiving LMWH (P = .667). Lower extremity DVT is common in critically ill trauma patients, particularly in the first week following injury, regardless of injury pattern, DVT risk factors, or pharmacologic prophylaxis. Previous studies have underestimated DVT rates by not investigating CVDVTs and not exclusively targeting critically ill patients. We recommend early and continued DUS DVT screening of all critically ill trauma patients.

Deep venous thrombosis screening in patients with inherited bleeding disorders and central venous catheters

Children with inherited bleeding disorders often require central venous catheters (CVCs). Although CVCs are known to be complicated by deep venous thrombosis (DVT), little is known about the timeline of DVT development or risk of post-thrombotic syndrome (PTS). The aim of this study was to determine the timeline and confirm the incidence of thrombosis in patients with bleeding disorders who have CVCs. In 2002, we instituted a screening programme to monitor for CVC-related complications in children with haemophilia and von Willebrand disease. This is a retrospective review of this cohort. All children with CVC followed up between 1 January 2000 and 1 June 2009 were evaluated for DVT every 24 months with contrast venography and Doppler sonography. An institutional PTS severity scale was utilized at each visit. Thirty-six patients had 37 CVCs placed. Thirty patients had imaging studies, with DVT observed in 14 (47%). Most cases of DVT were diagnosed at the first venogram (median CVC duration 26 months). There were no abnormal ultrasound results. Sixteen patients (44%) had clinical findings consistent with PTS, including 10 (71%) with an abnormal venogram. Dilated chest wall veins appeared to be more strongly associated with underlying DVT (positive predictive value of 0.8) than arm circumference discrepancy. Successful transition to use of peripheral veins occurred at a median of 11 months after abnormal venograms. CVC-related DVT is common in children with inherited bleeding disorders and likely occurs earlier than previously thought. Clinical signs of PTS are also common, but long-term sequelae and severity of PTS are not known.

The utility of screening for deep venous thrombosis in asymptomatic, non-ambulatory neurosurgical patients

Decisions regarding deep venous thrombosis (DVT) prophylaxis are complicated in neurosurgical patients because of the potential for catastrophic bleeding complications. Screening with venous duplex ultrasound (VDUS) may improve outcomes, but can strain hospital resources. Since there is little data to guide VDUS surveillance, we investigated the utility of a comprehensive VDUS screening program in neurosurgical patients. Medical records of patients admitted to the neurosurgical service at a university-affiliated hospital from October 2007 through January 2010 who underwent weekly VDUS of the lower extremities until ambulatory or discharged were retrospectively reviewed. Demographics, comorbidities, interventions, and use of DVT prophylaxis were recorded. All patients in this study were asymptomatic for clinical evidence of DVT. When DVT was identified, VDUS reported its location and progression. One hundred seventy-four consecutive patients were screened according to the established protocol. They had 312 VDUS studies, 68 (21.8%) of which were positive in 40 (23%) unique patients; 10 were bilateral and two catheter-related. There were no documented pulmonary emboli in this series. Seventeen patients (37.7%) had isolated calf DVT, four of which were bilateral (totaling 21 thrombi), and 9 (20%) had coexistent thrombi in calf and proximal veins. Of the 21 isolated calf DVTs, 15 had follow-up studies and two progressed to the popliteal or ileofemoral vein on follow-up (13.3%). Mechanical prophylaxis was uniformly utilized, but chemical prophylaxis varied based on surgeons' assessment of bleeding risk. DVT developed in 19.3% (28/145) of patients receiving prophylactic medication (unfractionated heparin or low-molecular weight heparin) and 41.4% (12/29) receiving no chemoprophylaxis (P < .001). The only patient characteristic that correlated with DVT risk was a body mass index <30 (9.1% vs 29.4%, P = .01). Despite the uniform application of mechanical DVT prophylaxis and the use of chemoprophylaxis in a majority of patients, we found a 23% incidence of DVT in these hospitalized, nonambulatory, neurosurgical patients. No patients with isolated calf DVT had an embolic complication but 13.3% progressed proximally in short-term follow-up. While chemical prophylaxis significantly reduced DVT risk, no factor was sufficiently predictive to exclude patients from screening. These data substantiate the importance of full leg VDUS screening and maximizing DVT prophylaxis in this high risk population.

Outcomes of Asymptomatic Screening for Deep Venous Thrombosis in Neurosurgical Patients

Outcomes of Asymptomatic Screening for Deep Venous Thrombosis in Neurosurgical Patients

Screening for deep venous thrombosis after idiopathic scoliosis surgery in children: a pilot study

Venous thrombosis remains an uncommon disorder in childhood. However, the incidence appears to be increasing for a multitude of reasons. The aim of the study was to detect asymptomatic deep venous thrombosis and prothrombotic diseases in nonsyndromic children undergoing scoliosis surgery. A prospective study including forty successive teenagers scheduled for posterior spinal fusion. Patients with scoliosis with a history of hemoglobinopathies, cardiac defects, blood clots, early onset osteoporosis, as well as patients with skeletal dysplasias and nonskeletal dysplastic syndromic entities have been excluded. The protocol was designed for active screening of deep venous thrombosis using color Doppler ultrasonography on a day before surgery and repeated on the 3rd, 7th and 15th day postoperatively. Evaluation of prothrombotic disorders included antithrombin and protein C activities, and total protein S antigen level. No patient has manifested clinical symptoms of venous thrombosis in our study. Preoperative Doppler and ultrasound examinations were normal in all patients. Although repeated Doppler ultrasonography demonstrated a transient small clot in two patients. Congenital antithrombin deficiency of 5% has been observed in one child only, without the development of deep venous thrombosis. Thromboembolic event seems to be rare after scoliosis surgery. Prophylaxis for venous thrombosis should not be recommended in such patient. But, larger series are required to confirm such results.

Excluding deep venous thrombosis in symptomatic outpatients: is fibrin monomer aid to D-dimer analysis?

Many studies have investigated the clinical accuracy of the D-dimer test in combination with pretest probability score for deep venous thrombosis (DVT) exclusion. However, few have evaluated its potential when combined with additional markers such as fibrin monomer. The aim of this study was to test the incremental usefulness of fibrin monomer for DVT screening in a bi-marker approach. This was achieved by adding the fibrin monomer to logistic models that included different D-dimer tests. Plasma concentrations of D-dimer and fibrin monomer were measured in 96 outpatients suspected of having DVT and in 76 patients selected from the total patient group according to pretest probability score (termed the DVT-unlikely group). We constructed receiver operating characteristic curves for three different D-dimer assays. Predictive probabilities from different logistic regression models and pair-wise comparisons of the areas under the receiver operating characteristic curve (AUCs) were calculated without and with fibrin monomer included in the models. For all three D-dimer assays, the AUCs were higher in the DVT-unlikely group compared with AUCs in the total patient group [but the differences were without statistical significance (P > 0.05)]. The calculated fibrin monomer AUCs (0.724 in the total patient group and 0.683 in the DVT-unlikely group) were lower than the D-dimer tests' AUCs. The AUCs obtained from logistic regression models that included the three D-dimer tests in the total patient group and the DVT-unlikely group were significantly increased when fibrin monomer was included in the model to such an extent that the AUCs for one of them indicated outstanding discriminative abilities. Simultaneous D-dimer and fibrin monomer determination provides a more valuable approximation for DVT exclusion compared with just D-dimer analysis. Bearing in mind that the fibrin monomer assay is now both more practical and more suited for routine clinical use, fibrin monomer determination could be a more commonly used parameter together with D-dimer and pretest probability score for DVT diagnosis in the future.

Serial compression B‐scan and Doppler sonography for the screening of deep venous thrombosis in patients with spinal cord injuries

To evaluate the usefulness of serial compression B-scan and Doppler sonography (US) in screening for deep venous thrombosis (DVT) of the lower extremities in patients with spinal cord injuries. Patients with paraplegia and tetraplegia due to spinal cord injuries were screened by a serial compression B-scan and Doppler US protocol for DVT of the bilateral lower extremities within the first 36 hours after admission, at day 7 and at day 21. In patients with DVT, a follow-up US examination was performed 3 weeks after diagnosis to assess thrombi distribution. Between January 2007 and March 2008, a total of 115 patients (75 males, 40 females), aged 19 to 85 years, were included. The first US examination documented a DVT in 44 cases (38.3%). After an initial negative scan, sonography after 7 days and 21 days showed DVT in 6 patients and 2 patients, respectively. Cumulative rate of DVT after the first 3 weeks was 45.2% (n=52). Follow-up US after 3 weeks in patients with DVT documented a complete recanalization in 19 patients (36.5%), no change in 12 patients (23.1%), and residual thrombi with partial recanalization in 21 patients (40.4%). Our study supports the use of serial compression B-scan and Doppler US as a screening tool for DVT of the lower extremities in patients with spinal cord injuries early after injury.

Thrombelastography Versus AntiFactor Xa Levels in the Assessment of Prophylactic-Dose Enoxaparin in Critically Ill Patients

A standard dose of enoxaparin is frequently used for deep venous thrombosis (DVT) prophylaxis. Evidence suggests inconsistent bioavailability in intensive care unit (ICU) patients. Antifactor Xa activity (anti-Xa) has been used to monitor enoxaparin dosing but its accuracy and availability are problematic. Thrombelastography (TEG) is used to evaluate coagulation in diverse settings. The purpose of this study was to analyze whether TEG could be used to predict which enoxaparin-treated patients would develop DVT. Two hundred sixty-one simultaneous enoxaparin-active (active) and enoxaparin-neutralized (neutral) TEGs were performed in 61 surgical ICU patients over four consecutive days. Patient characteristics and anti-Xa were collected. DVT screening was per ICU protocol. Mean (+/-SEM) age was 54 (+/-2.3) years and Acute Physiology and Chronic Health Evaluation II score was 17 (+/-0.7). There were 30 trauma and 31 general surgery patients (69% men). The DVT rate was 28%. Time to clot formation (R) and percent lysis at 30 minutes were different between active versus neutralized blood (p < 0.001). R time was 1.5 minutes shorter in patients with DVT versus those without (p < 0.001) indicating hypercoagulability in DVT patients. Anti-Xa levels were similar in patients with (0.135 +/- 0.012) and without (0.135 +/- 0.007) DVT (p = 0.97). There were no differences in age, body mass index, injury severity score, Acute Physiology and Chronic Health Evaluation II score, or trauma status between DVT and non-DVT groups. TEG demonstrates differences between enoxaparin-neutralized and enoxaparin-active blood in ICU patients that may be used to guide dosing. TEG differentiates enoxaparin-treated patients who subsequently develop DVT while anti-Xa levels do not. TEG demonstrates an enoxaparin-related increase in fibrinolysis.

Incidence of deep venous thrombosis after subarachnoid hemorrhage

The aim of this study was to determine the efficacy of venous ultrasonography in screening for deep venous thrombosis (DVT) after subarachnoid hemorrhage (SAH). A large cohort of patients who had suffered SAH was evaluated with the primary end points of ascertaining the incidence of asymptomatic DVT with venous Doppler ultrasonography screening and of identifying risk factors for the development of DVT and subsequent pulmonary embolism. Data from patients with aneurysmal SAH who had been admitted to the neurosurgical intensive care unit (ICU) between December 2002 and October 2006 were retrospectively evaluated. Patients who had undergone surgical or endovascular treatment of an aneurysm following SAH and survived > or = 15 days were included in the study. The overall incidence of DVT among the entire study cohort was 18%. A subgroup analysis identified all patients, with or without symptoms for DVT, who had undergone venous Doppler ultrasonography screening. The incidence of asymptomatic DVT was 24%. Univariate analysis of all patients revealed a significant correlation between the risk of DVT and Hunt and Hess grade (r = 0.38, p < 0.0001), Fisher grade (r = 0.31, p < 0.0001), total hospital stay (r = 0.49, p < 0.0001), and number of days in the ICU (r = 0.48, p < 0.0001). Multivariate analysis demonstrated that the total hospital stay and number of days in the ICU were significant predictors of DVT in all patients (p < 0.0001 and p < 0.0002, respectively). In the subgroup of screened patients, Hunt and Hess grade, total hospital stay, and number of days in the ICU were significant predictors of DVT. Although screened patients were more likely to have DVT (chi(2) = 6.0976, p < 0.02), there was no significant difference in the incidence of DVT or pulmonary embolism between patients who did and those who did not undergo routine lower-extremity Doppler ultrasonography screening. Routine compressive venous Doppler ultrasonography is an efficient, noninvasive means of identifying DVT as a screening modality in both symptomatic and asymptomatic patients following aneurysmal SAH. The ability to confirm or deny the presence of DVT in this patient population allows one to better identify the indications for chemoprophylaxis. Prophylaxis for venous thromboembolism in neurosurgical patients is common. Emerging literature and anecdotal experience have exposed risks of complications with prophylactic anticoagulation protocols. The identification of patients at high risk-for example, those with asymptomatic DVT-will allow physicians to better assess the role of prophylactic anticoagulation.

AUA Best Practice Statement for the Prevention of Deep Vein Thrombosis in Patients Undergoing Urologic Surgery

Summary of VTE prophylaxis recommendations Level of risk Prophylactic treatmentLow Risk ● No prophylaxis other than early ambulationModerate Risk ● Heparin 5000 units every 12 hours subcutaneous starting after surgery ● OR *Enoxaparin 40 mg. (Cr Cl 30 ml/min. 30 mg.) subcutaneous daily ● OR Pneumatic compression device if risk of bleeding is highHigh Risk ● Heparin 5000 units every 8 hours subcutaneous starting after surgery ● OR *Enoxaparin 40 mg. (Cr Cl 30 ml/min. 30 mg.) subcutaneous daily ● OR Pneumatic compression device if risk of bleeding is highVery High Risk ● *Enoxaparin 40 mg. (Cr Cl 30 ml/min. 30 mg.) subcutaneous daily and adjuvant pneumatic compression device, or ● Heparin 5000 units every 8 hours subcutaneous starting after surgery and adjuvant pneumatic compression device* Guidelines and Cautions for Enoxaparin Use ● In patients with a body weight 150 Kg. consider increasing prophylaxis dose of Enoxaparin to 40 mg. subcutaneous every 12 hours. ● Withhold Enoxaparin generally for at least 2 to 3 days after major trauma, and then only consider use after review of current patient condition and risk benefit ratio.

Subclinical Deep Venous Thrombosis Affects 10 % of Haemophiliacs Undergoing Major Orthopaedic Surgery.

The management of venous thromboembolism (VTE) in patients with haemophilia undergoing major orthopaedic surgery requiring intensive replacement therapy remains controversial. Information about the incidence of proven VTE in this setting is lacking. Despite the absence of data, half of haemophilia comprehensive centers in Europe recently reported the use of pharmacological antithrombotic prophylaxis in this setting.We conducted a prospective study to evaluate the occurrence of deep venous thrombosis (DVT) of the lower limbs in all consecutive patients with haemophilia referred for major orthopaedic surgery at the Cliniques universitaires Saint-Luc, Brussels, Belgium. Screening for DVT by unilateral (13) or bilateral (16) compression ultrasonography (US) of the lower limbs was performed 5 to 12 days after 29 major orthopaedic surgeries (total hip replacement (5), total knee replacement (TKR) (15), ankle arthrodesis (4), decompressive laminectomy for lumbar stenosis (1), femoral osteosynthesis (4)) in 22 patients with severe (16), moderate (4) or mild (2) haemophilia A (20) or B (2), intensively treated with continuous infusion of clotting factor concentrate. None of the patients received pharmacological anti-thrombotic prophylaxis with LMWH. There was no case of clinical DVT or pulmonary embolism during the 3-months post-operative clinical surveillance. However distal DVT involving a single peroneal vein without proximal extension was identified in two patients with severe HA after TKR and in one patient with mild HB after decompressive laminectomy. The latter was efficiently treated with a short course of LMWH. The two others resolved spontaneously without antithrombotic therapy.In conclusion, sub-clinical DVT affects up to 10 % of patients with haemophilia undergoing major orthopedic surgery. All thrombotic events were distal and resolved spontaneously or with a short course of LMWH without complications. This study suggests that routine screening for DVT by compressive US is indicated in patients with haemophilia undergoing major orthopaedic surgery and not receiving pharmacological thromboprophylaxis. Further studies are needed to determine if systematic pharmacological prevention of DVT is required in this setting as in patients without haemophilia.

Deep Venous Thrombosis Screening of Hemophilia Patients with Central Venous Catheters.

Introduction: Central venous catheters (CVC) are employed to manage patients with severe bleeding disorders. However, up to 50% of these children may develop CVC-related deep vein thrombosis (CVC-DVT). Due to the high risk of CVC-DVT, in 2001 we instituted a DVT screening program consisting of performing contrast venograms and Doppler sonograms every two years after CVC insertion and regular assessment for signs or symptoms of post-thrombotic syndrome (PTS). Identification of early vascular changes prompted transitioning of patients to peripheral vein (PV) access within the following 12 months. We now report the outcome of this screening program.Methods: We reviewed all patients with inherited bleeding disorders who had CVCs placed during 2000–08. Data collected included CVC type, location, duration, associated complications, and imaging results. Examination findings of prominent chest wall veins and arm circumference discrepancies were also recorded. We evaluated the time to transition to PV infusions.Results: Thirty-six patients were studied, of whom 28 had Factor VIII deficiency, 6 Factor IX deficiency, and 2 severe von Willebrand disease. Thirty catheters were placed for prophylaxis and 7 for immune tolerance induction. One patient had 2 lines placed. Median age at line placement was 25 months. Catheters were inserted into the subclavian (n=15), external jugular (n=16), internal jugular (n=3), or facial vein (n=1); the site of 2 catheters is unknown. CVCs were in place a median of 41.3 ± 22.8 months. In 27 patients, the first venogram was performed at a median time of 25.5 months after placement. Of the other 9 patients (10 catheters), 5 catheters were in place ≤ 24 months, 1 CVC was removed without imaging, 2 patients transferred to other programs, 1 CVC was removed for infection within one month after placement, and 1 child died from sepsis with CVC in place (Haemophilia 2006; 12: 183–6). Thirteen patients (36%) had evidence on venogram of DVT (defined as: 1) thrombosis, 2) stenosis, 3) post-stenotic dilation, or 4) multiple visible collaterals). Ten abnormalities were detected on first venogram and 3 on the second. None had an abnormal sonogram. Of the patients with abnormal venograms, 6 CVCs were in the subclavian and 7 in the external jugular vein. Median time from insertion to DVT identification was 26 ± 19.7 months. There was no difference in CVC duration between patients with and without abnormal venogram results. Seven CVCs were removed in patients with positive venograms. Median time between the abnormal venogram result and CVC removal was 10 months. Delay in removal of CVC was secondary to difficult peripheral access or parental resistance. Nine (69%) patients with CVC-DVT had dilated chest wall veins and/or ipsilateral arm swelling (conventional signs of PTS). Excluding symptomatic joint disease, no patient complained of arm pain or dysfunction.Conclusion: Early screening identified a CVC-DVT incidence of 28% within 2 years and 36% within 4 years. Successful transition to PV infusion is usually possible within a year after vascular changes and before 5 years of CVC use. In addition, 69% of those with CVC-DVT had evidence of mild PTS. The late sequelae of CVC-DVT are unknown. Therefore, screening for DVT, early transition to PV, and long-term follow-up is essential when CVCs are used for children with inherited bleeding disorders.

Disease-specific screening for deep venous thrombosis and pulmonary thromboembolism using plasma d-dimer values after total knee arthroplasty

We prospectively evaluated the disease-specific features of the early postoperative plasma d-dimer value and the relationship with deep venous thrombosis and/or pulmonary thromboembolism (DVT/PE) in 95 patients following total knee arthroplasty. Patients in whom DVT/PE was highly suspected were diagnosed by high-resolution multi-detector row computed tomography scanning (MDCT). Forty-nine knees in 46 patients with rheumatoid arthritis (RA, 24 knees) or osteoarthritis (OA, 25 knees) were finally recruited. DVT/PE was detected in 28 (57.1%) of the 49 cases examined by diagnostic MDCT: 12 (50.0%) of the 24 cases of RA, and 16 (64.0%) of the 25 cases of OA. Of these, PE was found in 11 cases (39.2%), but none of them showed clinical symptomatic signs of dyspnea or chest pain. In both RA and OA cases, there were statistically significant differences in the d-dimer value on postoperative day 3 (P = 0.027) and after day 28 (P = 0.037) between the groups with and without DVT/PE. In OA cases, there were significant differences between the two groups on postoperative days 1 (P = 0.034), 3 (P = 0.020), 5 (P = 0.005), and 7 (P = 0.045), respectively. At the baseline, perioperative d-dimer levels in the RA group without DVT/PE were higher than in the OA group. However, multivariate logistic regression analysis showed that RA was not a significant risk factor of DVT/PE in comparison with OA. In conclusion, individual evaluation of the d-dimer level between RA and OA should provide a more precise predictive indicator of early postoperative DVT/PE.

Disease-specific screening for deep venous thrombosis and pulmonary thromboembolism using plasma d-dimer values after total knee arthroplasty

We prospectively evaluated the disease-specific features of the early postoperative plasma D: -dimer value and the relationship with deep venous thrombosis and/or pulmonary thromboembolism (DVT/PE) in 95 patients following total knee arthroplasty. Patients in whom DVT/PE was highly suspected were diagnosed by high-resolution multi-detector row computed tomography scanning (MDCT). Forty-nine knees in 46 patients with rheumatoid arthritis (RA, 24 knees) or osteoarthritis (OA, 25 knees) were finally recruited. DVT/PE was detected in 28 (57.1%) of the 49 cases examined by diagnostic MDCT: 12 (50.0%) of the 24 cases of RA, and 16 (64.0%) of the 25 cases of OA. Of these, PE was found in 11 cases (39.2%), but none of them showed clinical symptomatic signs of dyspnea or chest pain. In both RA and OA cases, there were statistically significant differences in the D: -dimer value on postoperative day 3 (P = 0.027) and after day 28 (P = 0.037) between the groups with and without DVT/PE. In OA cases, there were significant differences between the two groups on postoperative days 1 (P = 0.034), 3 (P = 0.020), 5 (P = 0.005), and 7 (P = 0.045), respectively. At the baseline, perioperative D: -dimer levels in the RA group without DVT/PE were higher than in the OA group. However, multivariate logistic regression analysis showed that RA was not a significant risk factor of DVT/PE in comparison with OA. In conclusion, individual evaluation of the D: -dimer level between RA and OA should provide a more precise predictive indicator of early postoperative DVT/PE.

Gestational related changes in the deep venous system of the lower limb on light reflection rheography in pregnancy and the puerperium

To assess whether light reflection rheography testing is affected by the changes that occur in the deep venous system of the lower limb in pregnancy and the puerperium. Twenty five women with a singleton pregnancy were recruited to undergo duplex Doppler ultrasound examinations of the common femoral vein to measure the vessel diameter and the blood flow velocity. Light reflection rheography testing was subsequently performed and the rate of venous emptying in the lower limb calculated. Serial measurements using both techniques were made at 15, 28, 36 weeks, and term gestation and at 2 days and 6 weeks postpartum. Duplex Doppler ultrasound confirmed that there is progressive dilatation of the deep venous system in pregnancy, which reaches a maximum at term and reverses after delivery. There is an accompanying reduction in blood flow velocity, which reaches a nadir at term and increases after delivery. The rate of venous emptying as measured by light reflection rheography decreases with increasing gestation, but did not fall to a level consistent with venous occlusion by a deep venous thrombosis. Light reflection rheography has been shown to provide reliable results in pregnancy and the puerperium. Therefore, it is a potential tool for screening for deep venous thrombosis in this population.

Role of Screening Tests for Deep Venous Thrombosis in Asymptomatic Adults With Acute Spinal Cord Injury

Systematic review. To examine the evidence to support practice guidelines for screening for DVT in asymptomatic adults with acute traumatic spinal cord injury (SCI) who undergo pharmacologic thromboprophylaxis. Despite the fact that pharmacologic thromboprophylaxis has been widely used since the 1980s, deep venous thrombosis (DVT) and subsequent pulmonary embolism (PE) still account for approximately 10% of deaths during the first year following SCI. MEDLINE and EMBASE were searched from the earliest achievable date to December 2005. We only included clinical studies that used a screening test for DVT and the gold standard diagnostic tests for DVT (i.e., lower limb venography) and for PE (i.e., lung arteriogram) in adults with traumatic SCI who underwent drug thromboprophylaxis during the acute stage after SCI. The search yielded 188 articles, of which 9 articles fulfilled the criteria to be included in our review. Screening for DVT was performed in 3 randomized clinical trials and 6 case series. The protocol of these studies included the use of D-Dimer (1 of 9), I-labeled fibrinogen (2 of 9), ultrasound (1 of 9), impedance plethysmography (1 of 9), impedance plethysmography and Doppler in combination (1 of 9), Duplex (1 of 9) or venography (2 of 9) as screening test for DVT. Based on the pooled data of these studies, asymptomatic DVT was detected in 16.9% of SCI population. Only 4 studies reported the occurrence of PE in 4.4% of cases. There is insufficient evidence to support (or refute) a recommendation for routine screening for DVT in adults with acute traumatic SCI under thromboprophylaxis. However, there is level II-2 evidence that screening could detect asymptomatic DVT in 22.7% of those individuals. Although additional investigation is needed, we hypothesize that weekly screening for DVT during the first 13 weeks post-SCI could detect most of the asymptomatic DVT events in this patient population. D-Dimer, ultrasound, and MR venography could be considered as potentially useful screening tests for DVT in the SCI population in future research studies.

Accuracy of Compression Ultrasound in Screening for Deep Venous Thrombosis in Acutely Ill Medical Patients

Ultrasound Quarterly: June 2007 - Volume 23 - Issue 2 - p 151 doi: 10.1097/01.ruq.0000277017.39146.f7

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

Background: 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. Methods: 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. Results: 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. Conclusions: 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. Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.