Deep vein thrombosis in stroke. The use of plasma D-dimer level as a screening test in the rehabilitation setting

Risk factors for lower extremity deep vein thrombosis in acute stroke patients following endovascular thrombectomy: a retrospective cohort study

Background

Deep vein thrombosis (DVT) in lower extremities as a common complication of acute ischemic stroke (AIS) has long been studied. However, as the therapeutic options for AIS continue to advance, the pathogenic mechanisms behind DVT may change. Endovascular thrombectomy (EVT) has replaced intravenous thrombolysis and become the preferred treatment for AIS patients with large vessel occlusions. Therefore, it is important to update our understanding of DVT and its management. This study aimed to determine the prevalence and risk factors of DVT in AIS patients following EVT.

Methods

In this retrospective study, 245 AIS patients who had received EVT were recruited between January 2020 and December 2021. Within 10 days (median 4 days) of thrombectomy, DVT was diagnosed by ultrasonography. Demographic characteristics, clinical findings, and therapeutic procedures were compared between patients with and without DVT using univariate analysis. Cutoff points were defined for EVT time and plasma D-dimer concentration. Multivariable logistic regression was then used to determine the independent risk factors for DVT and evaluate their predictive power.

Results

The prevalence of DVT in AIS patients after EVT was 27.3%. Multifactorial logistic regression analysis showed that age (OR 1.036, 95% CI 1.001-1.073; P = 0.045), female sex (OR 3.015, 95% CI 1.446-6.289; P = 0.003), lower limb muscle strength less than grade three (OR 7.015, 95% CI 1.887-26.080; P = 0.004), longer EVT time (OR 1.012, 95% CI 1.004-1.020; P = 0.003), and higher D-dimer levels (OR 1.350, 95% CI 1.150-1.585; P < 0.001) were independently associated with higher DVT risk in AIS patients following EVT. The cutoff points for operative time of EVT and plasma D-dimer were 65.5 min and 1.62 mg/L, respectively, above which the risk for DVT was dramatically increased with OR > 4 in AIS patients.

Conclusion

AIS patients are at increased risk of developing DVT following EVT particularly if they have undergone prolonged thrombectomy procedures and exhibit high plasma levels of D-dimers. However, the results of our study need to be validated by a multicenter prospective study with a larger population of stroke patients.

Risk factors and predictors for venous thromboembolism in people with ischemic stroke: A systematic review

Identification of individuals with ischemic stroke at particularly high risk of venous thromboembolism (VTE) is crucial for targeted thromboprophylaxis. To guide clinical decision-making and development of risk prediction models, increased knowledge on risk factors and biomarkers is needed. Therefore, we set out to identify risk factors and predictors for VTE in people with ischemic stroke by conducting a systematic review of the literature. Medline and Embase were searched from January 1990 and onwards. Studies investigating demographic, clinical, and/or laboratory factors for stroke-related VTE were considered. Two reviewers screened all retrieved records, independently and in duplicate. Risk of bias assessments were guided by a structured framework (PROSPERO-ID: CRD42020176361). Of 4674 identified records, 26 studies were included. Twenty-six demographic, clinical, and laboratory factors associated with increased risk of stroke-related VTE after multivariable adjustments were identified. The following factors were reported by ≥2 studies: prior VTE, cancer, prestroke disability, leg weakness, increasing lesion volume of the brain infarct, infection, low Barthel Index, increasing length of hospital stay, biochemical indices of dehydration, as well as elevated levels of D-dimer, C-reactive protein, and homocysteine. The majority of the studies were of poor quality with moderate or high risk of bias. In conclusion, this systematic review informs on several potential risk factors and predictors for VTE in people with ischemic stroke. To improve risk stratification and guide development of risk prediction models, further confirmation is needed because there were few high-quality studies on each factor.

A Systematic Review of the Predictive Value of Plasma D-Dimer Levels for Predicting Stroke Outcome

Background: Stroke is a leading cause of morbidity and mortality. Over the past decade, plasma D-dimer levels have emerged as a biomarker for predicting stroke outcome. However, no consensus in the literature currently exists concerning its utility for predicting post-stroke functional outcome and mortality. Objective: To systematically review the effectiveness of plasma D-dimer levels for predicting functional outcome and mortality following stroke. Methods: Five academic databases were screened according to PRISMA guidelines for eligible studies. With these studies, we conducted a random-effect meta-analysis to evaluate the impact of plasma D-dimer levels for predicting functional outcome and mortality post-stroke. We also conducted subgroup analyses to evaluate differences in predictive capacity for different stroke subtypes. Results: Nineteen studies were included, containing data on 5,781 stroke patients (mean age: 65.26 ± 6.4 years). Overall methodological quality for the included studies was high. Meta-analysis showed that increased D-dimer levels were predictive of worsened functional outcomes (Hazard ratio: 2.19, 95% CI: 1.63-2.93) and elevated overall mortality (2.29, 1.35-3.88). Subgroup analysis showed that plasma D-dimer levels were more predictive of poorer functional outcomes for ischemic (2.08, 1.36-3.18) stroke as compared to intracerebral hemorrhage (2.62, 1.65-4.17). We also noted that predictive capacity was similar when it came to mortality in patients with cryptogenic ischemic stroke (2.65, 0.87-8.08) and intracerebral hemorrhage (2.63, 1.50-4.59). Conclusion: The study provides preliminary evidence concerning the capacity of plasma D-dimer levels for predicting functional outcomes and mortality following stroke and reports that higher D-dimer levels of are associated with poorer functional outcomes and higher mortality.

The Risk Factors for Death within 6 Months After Ischemic Stroke in Patients with Cancer

OBJECTIVES

While the intravenous recombinant tissue plasminogen activator (rt-PA) therapy for acute ischemic stroke patients with cancer is recommended when survival of ≥ 6 months is expected, the risk factors for death and stroke recurrence within 6 months after stroke are not well known. Thus, we aimed to identify markers for death and recurrence risks within six months from stroke onset in patients with cancer.

MATERIALS AND METHODS

In a retrospective cohort study, the subjects comprised acute ischemic stroke patients with cancer hospitalized at St. Marianna University hospital from 2008 through 2019. To evaluate the associations between the clinical factors within 24 h of the initial stroke and death or stroke recurrence events within 6 months from stroke onset, Logistic analysis and Cox proportional hazards regression analysis was used respectively. Next, the optimal cutoff point of markers for different mortality groups was determined using the receiver operating characteristic curve analysis and cumulative outcome rate of each group was compared using the Kaplan-Meier method.

RESULTS

Among 194 patients with cancer who developed acute stroke, 167 were ultimately selected for analysis. 47 subjects (28.14%) passed away within 6 months following stroke onset, and 20 subjects (11.98%) had stroke recurrence. High D-dimer levels, low fibrinogen levels, high Glasgow prognostic scores (GPS), and multiple vascular territory infarctions was independently associated with death, where higher death rate was significantly confirmed in the group with D-dimer levels of ≥3.95 mg/dl, fibrinogen levels <277.5 mg/dl and GPS scores of 2. Low fibrinogen level, lack of antithrombotic therapy, and the presence of metastasis were associated with stroke recurrence.

CONCLUSIONS

When patients with cancer suffer stroke, D-dimer levels, fibrinogen levels, GPS, and multiple vascular territory infarctions would be associated with the risk of death within 6 months. Low fibrinogen levels, lack of antithrombotic therapy, and the presence of metastasis correlated with high risk of stroke recurrence.

Prevention of Venous Thromboembolism After Stroke

Venous thromboembolism (VTE) is a common complication following acute ischemic and hemorrhagic stroke. Pulmonary embolism (PE), the most serious consequence of deep vein thrombosis (DVT), can result in significant morbidity and death. Patients with stroke are at particular risk because of limb paralysis, prolonged bed rest, and increased prothrombotic activity. Preventive measures should be taken at all levels of care and can include mechanical calf compression, antiplatelet agents, and the use of anticoagulants such as heparin and low molecular weight heparin. Prevention of VTE should be incorporated into all stroke care pathways.

Usefulness of the computed tomography venography for evaluation of leg edema including deep vein thrombosis in rehabilitation patients

Objective

To investigate the usefulness of computed tomography venography (CTV) for evaluation of leg swelling, especially deep vein thrombosis (DVT), in rehabilitation patients.

Methods

A hundred twenty-three patients, who had performed CTV performed because of suspected DVT in our clinic, were enrolled. We performed chart reviews retrospectively and categorized CTV findings as follows: DVT distal to inguinal ligament and no compression lesion; DVT proximal to inguinal ligament and no compression lesion; DVT distal to inguinal ligament and anatomical variant (for example, May-Thurner syndrome); DVT due to compression of mass (cancer or cyst); DVT and other incidental abnormal finding; and no DVT and other possible causes of leg swelling.

Results

DVTs were found in 65 (53%) patients. DVTs were found at distal level (thigh or lower leg) to inguinal ligament in 47 patients. DVTs were found at proximal to inguinal ligament, usually undetectable with duplex ultrasonography, in 6 patients. DVTs caused by external compression, such as femoral vein and cancer mass, were found in 12 patients (10%), which are also not easily detected with duplex ultrasonography. Other various causes of leg edema without DVT were found in 22 (18%) patients.

Conclusion

CTV can evaluate more extensively venous problems in the pelvis and abdomen and detect other possible causes of leg swelling. Therefore, CTV can be a useful tool not only for easy detection of DVT but also for evaluating differential diagnosis of leg edema in rehabilitation patients.

Prevention of venous thromboembolism in patients with hemorrhagic stroke

Deep venous thrombosis (DVT) and pulmonary embolism (PE) are part of the spectrum of venous thromboembolism (VTE). It is one of the most frequent medical complications in stroke patients. The risk of VTE is even higher after hemorrhagic stroke. This article reviews various screening methods, diagnostic techniques, and pharmacologic as well as nonpharmacologic means of preventing VTE after hemorrhagic stroke.

[Association of location of deep venous thrombosis and d-dimer value in acute intracerebral hemorrhage]

AIM

We investigated the association of the presence and the location of deep venous thrombosis (DVT) with D-dimer value in acute intracerebral hemorrhage (ICH).

METHODS

We analyzed the data regarding DVT in patients with ICH. Based on an ultrasonographic examination 2 weeks after the occurrence of ICH, the patients were divided according to the presence/absence and the location of DVT, i.e. no evidence of DVT (n-DVT), calf DVT (c-DVT), and proximal DVT (p-DVT). D-dimer value was measured 2 weeks later and compared among the groups.

RESULTS

The numbers of patients with n-DVT, c-DVT and p-DVT were 27, 19, and 2, respectively. Univariate analysis indicated that D-dimer values were significantly different between patients with n-DVT and c-DVT and between patients with n-DVT and p-DVT (p<0.05, respectively). The cut-off value for estimating the presence of DVT and p-DVT was 3.9 µg/mL and 18.5 µg/mL, respectively.

CONCLUSION

D-dimer value assessment after 2 weeks may be associated with the presence and the location of DVT in patients with ICH.

Deep vein thrombosis in stroke patients admitted to a rehabilitation unit in Singapore

BACKGROUND

Studies have shown that deep vein thrombosis (DVT) is common after an acute stroke. Less common are studies documenting DVT in stroke patients admitted to rehabilitation. The purpose of this study was to determine the frequency and risk factors of DVT in stroke patients admitted to a rehabilitation unit in Singapore.

METHODS

A prospective observational single-center study of patients with ischemic and hemorrhagic stroke with lower limb paresis admitted to a rehabilitation center in Singapore. The screening protocol consisted of quantitative D-dimer assay (DDA) within 24-48 h of rehabilitation admission followed by duplex ultrasound scan of the paretic lower extremity if DDA level was elevated (equal or greater than 0.34 microg/ml).

RESULTS

Altogether, 341 patients were screened at a mean of 23 days poststroke. One hundred and ninety-eight (58.1%) patients had an elevated DDA and all underwent ultrasound scans. The frequency of lower limb DVT was 9% (18) - seven proximal and 11 distal. DVT was significantly related to higher D-dimer levels (P=0.029) and cortical strokes (P=0.004), but not to age, gender, race, nature of stroke, atrial fibrillation, severity of lower limb weakness, and ambulatory and functional status. No patients had clinical pulmonary embolism during rehabilitation.

CONCLUSIONS

Lower limb DVT is uncommon in stroke patients admitted to rehabilitation in Singapore. Future research should include evaluation of the cost-effectiveness of such a screening protocol.

Is D-dimer helpful in evaluating stroke patients? A systematic review

D-dimer (DD) is a fibrin degradation product present in negligible amounts in healthy individuals, but in thrombotic/fibrinolytic conditions substantially increases in plasma. Over the last two decades numerous studies have explored whether DD measurements would help stroke clinicians. An easy, reliable, and inexpensive test for stroke diagnosis, determination of stroke subtype, severity, prognosis, and recurrence risk is being sought. We searched the database, of studies indexed in English on MEDLINE, using the keywords 'cerebral venous thrombosis, D-dimer, deep vein thrombosis, intracerebral hemorrhage, ischemic stroke, outcome, prognosis, and subarachnoid hemorrhage' for relevant studies. Here, we systematically review current evidence on plasma DD levels in patients with ischemic and hemorrhagic strokes, transient ischemic attacks, and cerebral venous thrombosis. Numerous studies showed that patients with various strokes and stroke-related diseases had acutely increased plasma DD levels. Plasma DD levels, however, are neither sensitive nor specific enough to be utilized in stroke diagnostics and cannot replace either clinical or radiological evaluation. Regarding prediction of patient outcome, good clinical evaluation is clearly superior to DD testing.

Prevalence and risk factors of asymptomatic lower extremity deep venous thrombosis in Asian neurorehabilitation admissions in Singapore

OBJECTIVE

To determine the local prevalence and risk factors of asymptomatic lower limb deep venous thrombosis (DVT) among neurorehabilitation admissions.

DESIGN

A prospective observational single-center study.

SETTING

Tertiary rehabilitation center affiliated to a public hospital.

PARTICIPANTS

A total of 419 Asian neurorehabilitation admissions with a mean of 26 days to rehabilitation.

INTERVENTION

Admission screening protocol included quantitative D-dimer assay within 24 to 48 hours of rehabilitation admission and targeted hemiplegic/weaker lower-extremity venous duplex ultrasonography was performed if D-dimer assay level was elevated at 0.34 microg/mL or higher.

MAIN OUTCOME MEASURES

There were 251 (59.9%) men, and the subjects were predominantly Chinese (76.6%). Subjects had a mean age of 59+/-15 years. Admitting diagnoses included ischemic stroke (212), hemorrhagic stroke and subarachnoid hemorrhage (129), traumatic brain injury (59), and nontraumatic brain injury (19). The screening protocol included a quantitative D-dimer assay within 24 to 48 hours of rehabilitation admission, and hemiplegic/weaker lower-extremity venous duplex ultrasonography was performed if D-dimer assay level was elevated at 0.34 microg/mL or higher.

RESULTS

Altogether, 247 (58.9%) patients had an elevated D-dimer assay, and all underwent venous duplex ultrasonography. The incidence of lower-limb DVT was 5.01% (21), including 11 proximal and 10 distal DVT. No patients had clinical pulmonary embolism. Using 247 venous duplex ultrasonography results for analyses of correlates with logistic regression analyses, no significant demographic or clinical predictive factors for DVT were found.

CONCLUSIONS

This study confirms that asymptomatic lower limb DVT is indeed uncommon in Asian neurorehabilitation admissions. Possible reasons include genetic or ethnic protective factors, early walking initiated at rehabilitation, and timing of the admission protocol (median of 14 days postevent) when the maximal thrombotic risk was on the decline.

The value of D-dimer in the detection of early deep-vein thrombosis after total knee arthroplasty in Asian patients: a cohort study

Background and purpose

The relationship of D-dimer and deep-vein thrombosis (DVT) after total knee arthroplasty (TKA) remains controversial. The purpose of this study was to assess the value of D-dimer in the detection of early DVT after TKA.

Methods

The measurements of plasma D-dimer level were obtained preoperatively and at day 7 postoperatively in 78 patients undergoing TKA. Ascending venography was performed in 7 to 10 days after surgery. The plasma D-dimer levels were correlated statistically with the venographic DVT.

Results

Venographic DVT was identified in 40% of patients. High plasma D-dimer level >2.0 μg/ml was found in 68% of patients with DVT and 45% without DVT (P < 0.05). Therefore, high D-dimer level greater than 2.0 μg/ml showed 68% sensitivity, 55% specificity, 60% accuracy, 50% positive predictive rate and 72% negative predictive rate in the detection of early DVT after TKA.

Conclusion

High plasma D-dimer level is a moderately sensitive, but less specific marker in the detection of early of DVT after TKA. Measurement of serum D-dimer alone is not accurate enough to detect DVT after TKA. Venography is recommended in patients with elevated D-dimer and clinically suspected but asymptomatic DVT after TKA.

Early Deep Vein Thrombosis: Incidence in Asian Stroke Patients

Introduction: Deep venous thrombosis (DVT) is thought to be less common in Asians than in the Caucasian population. The incidence of asymptomatic DVT in high-risk groups in the Asian population has not been well studied. While DVT incidence among Caucasian stroke patients has been extensively studied and the need for prophylaxis established, the lack of data in Asian patients leaves physicians with no firm basis for adopting prophylactic protocols in the local population. Our aim was to prospectively establish the incidence of early DVT in immobilised stroke patients in a heterogenous Asian population. Materials and Methods: We screened 44 patients with significant hemiplegia from acute stroke. Doppler ultrasound, the currently accepted method of investigation for DVT, was used to study patients on admission and at 1 week post-stroke. While there was no standard prophylactic regime in use, none of the patients received heparin and only 2 were given compression stockings. Results: The incidence of DVT at 1 week was 2.4%. Review at 1 month detected another patient with DVT, bringing the overall incidence at 1 month to 4.8%. This is lower than in Caucasian populations, but is similar to another local study on a different group of high-risk patients. Conclusion: The low incidence of early DVT in hospitalised stroke patients of Asian ethnicity does not justify routine screening for this population. Further research to validate this should ideally include a comparison test for DVT as ultrasound may have inherently lower sensitivity in an asymptomatic population. Key words: Doppler ultrasound

Cost-effectiveness of screening for deep vein thrombosis by ultrasound at admission to stroke rehabilitation

OBJECTIVE

This project was a cost-effectiveness analysis of the practice of routine Doppler ultrasound screening for deep vein thrombosis (DVT) in patients with ischemic stroke at the time of admission to rehabilitation.

DESIGN

A decision-analysis model was created to compare 2 approaches for detecting DVT in a stroke population: (1) screening all patients with acute ischemic stroke at admission to stroke rehabilitation for DVT by Doppler ultrasound with subsequent treatment; or (2) clinical surveillance for signs of DVT and treatment after confirmation by Doppler ultrasound. The prevalence of DVT, risk of complication from DVT, and risk of complication from treatment were obtained from published reports. Costs are in 2004 dollars and the effectiveness was measured in quality-adjusted life-years (QALYs) gained. We conducted these analyses from a societal perspective.

SETTING

Inpatient stroke rehabilitation unit.

PARTICIPANTS

Not applicable.

INTERVENTION

Screening all patients with acute ischemic stroke at admission to stroke rehabilitation for DVT by Doppler ultrasound with subsequent treatment.

MAIN OUTCOME MEASURE

Cost in 2004 dollars per QALY gained by screening all patients with acute ischemic stroke at admission to stroke rehabilitation for DVT by Doppler ultrasound with subsequent treatment.

RESULTS

The expected utility of screening patients with ischemic stroke for DVT by Doppler ultrasound on admission to rehabilitation is 1.875 QALYs and that of not screening is 1.872 QALYs. The expected gain is .0026 QALYs (23 h). Obtaining this increase in quality-adjusted life incurs additional cost of 168 dollars per stroke patient and a marginal cost-effectiveness of 67,200 dollars for each QALY gained.

CONCLUSIONS

This study estimates that the cost-effectiveness ratio is considerably higher than that reported in other rehabilitation conditions and higher than the commonly stated level for an intervention to be considered cost-effective. The difference from previous reports primarily relates to the shorter life expectancy following stroke, the prevalence of occult DVT at admission, rate of complications of anticoagulation, and the estimates of the screening's test characteristics used in our study. Further study of these areas is likely to contribute to improving our understanding of the most appropriate care of these patients.

Variation in the diagnostic performance of D-dimer for suspected deep vein thrombosis

BACKGROUND

Numerous studies have evaluated the accuracy of D-dimer in diagnosing suspected deep vein thrombosis (DVT), but results are conflicting.

AIM

To overview estimates of the diagnostic accuracy of D-dimer and identify causes of variation.

DESIGN

Systematic review, meta-analysis and meta-regression.

METHODS

We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, citation lists, and contacted manufacturers. We selected studies that compared D-dimer to a reference standard in patients with suspected DVT. Data were analysed by random effects meta-analysis and meta-regression.

RESULTS

We included 97 studies reporting 198 assays in 99 different patient groups. Overall estimated sensitivity and specificity of D-dimer were 90.5% and 54.7%, but both estimates were subject to significant heterogeneity (p < 0.001). Meta-regression identified that some heterogeneity was explained by study setting, exclusion criteria, whether recruitment was consecutive or the study prospective, whether D-dimer and the reference standard were measured blind, and whether the D-dimer threshold was determined a priori. Sensitivity and specificity also varied between ELISA (94% and 45% respectively), latex (89% and 55%) and whole blood agglutination assays (87% and 68%). Sensitivity was higher for proximal than distal DVT. Specificity was dependent upon whether clinical probability of DVT was high (specificity 51%), intermediate (67%) or low (78%).

DISCUSSION

D-dimer has good sensitivity, but poor specificity, for DVT. Estimates are subject to substantial heterogeneity from various sources. D-dimer specificity appears to be strongly dependent upon the pre-test clinical probability of DVT.

Screening for proximal deep vein thrombosis after acute ischemic stroke: a prospective study using clinical factors and plasma D-dimers

Deep vein thrombosis (DVT) remains common in patients with acute ischemic stroke (AIS) receiving aspirin and graded compression stockings (considered standard thromboprophylaxis in the UK), most events occurring in patients with Barthel indices (BI) of <9 ('severe stroke') around the time of admission. In the absence of data indicating improved clinical outcomes with use of low-dose anticoagulant thromboprophylaxis, we evaluated the hypothesis that plasma D-dimers (D-d) might be a valuable initial screening test for proximal DVT (PDVT), facilitating selective use of imaging. One hundred and two unselected AIS-patients receiving aspirin/graded compression stockings thromboprophylaxis were screened for DVT using magnetic resonance direct thrombus imaging, a highly accurate non-invasive technique which directly visualizes thrombus. D-d (VIDAS and IL test D-d assays) were measured on recruitment and at weekly intervals. Median D-d were significantly higher throughout the study in patients with severe stroke who developed PDVT vs. those with severe stroke not developing PDVT, differences being most marked around day 9. Depending on the discriminatory threshold used, a single D-d measurement at this time in patients with severe-AIS allowed identification of a subgroup with ~50% prevalence of PDVT. Sensitivity of these strategies for PDVT was 67-83%, at a cost of imaging 22-30% of the entire cohort of patients. A single measurement of BI around the time of admission and D-d level at day 9 in AIS-patients receiving aspirin/graded compression stockings thromboprophylaxis allows identification of a subgroup containing a substantial proportion of all PDVTs who could be selectively imaged.

The relationship between acute ischaemic stroke and plasma D-dimer levels in patients developing neither venous thromboembolism nor major intercurrent illness

The true relationship between plasma D-dimers and acute ischaemic stroke (AIS) is uncertain as previous studies investigating this have not screened for subclinical deep vein thrombosis. We addressed this as part of a study in which we screened AIS patients for venous thromboembolism (VTE). We also assessed the performance characteristics of two D-dimer assays as exclusionary tests for VTE in these patients. One hundred and two unselected AIS patients were screened for VTE using magnetic resonance direct thrombus imaging. D-dimers were analysed on days 2, 9, 14 and 21 using the VIDAS immunofluorescent assay (cut-off >or= 500 ng/ml) and the IL test D-dimer immunoturbidimetric assay (cut-off >or= 255 ng/ml). The relationship between D-dimers and AIS was examined in 52 patients neither developing VTE nor intercurrent illness. D-dimers were elevated throughout the study. Median values at the four time points were 652, 692, 737 and 686 ng/ml (VIDAS assay) and 260.5, 268.5, 273 and 283 ng/ml (IL assay). D-dimers were higher in patients aged older than 70 years, with severe stroke or with total anterior circulation infarcts: only age older than 70 years was significantly associated with D-dimer values greater than the median on univariate and multivariable analysis. Both assays were 100% sensitive for VTE. Specificities were 30% (VIDAS assay) and 34% (IL assay). Specificity was adversely affected by age older than 70 and severe versus non-severe stroke. D-dimers are elevated in the first 3 weeks post-AIS after eliminating the confounding effect of subclinical deep vein thrombosis. The VIDAS and IL assays remained sensitive tests for VTE but the specificity was low, limiting their exclusionary efficiency in these patients.

The effectiveness of anticoagulant and antiplatelet agents in preventing venous thromboembolism during stroke rehabilitation: a historical cohort study

OBJECTIVE

To determine the effectiveness of anticoagulant and antiplatelet agents in preventing venous thromboembolism (VTE) during stroke rehabilitation.

DESIGN

Historical cohort study.

SETTING

Acute inpatient rehabilitation hospital.

PARTICIPANTS

Consecutive patients (N=1506) with ischemic and hemorrhagic stroke admitted for rehabilitation.

INTERVENTIONS

Documented use of anticoagulants (warfarin or anticoagulant doses of heparin), heparin in prophylactic doses, and antiplatelet agents.

MAIN OUTCOME MEASURE

Occurrence of deep vein thrombosis detected by ultrasound or venography or pulmonary embolism detected by ventilation perfusion scan, spiral computed tomography, or pulmonary angiography.

RESULTS

Fifty-eight VTE events occurred (3.9% incidence or 1.36 events per 1000 patient days), with higher risk in patients with severe stroke. Only therapeutic anticoagulation had a statistically significant protective effect for VTE risk in univariate analysis (odds ratio [OR]=.44; 95% confidence interval [CI],.20-.98). After adjusting for multiple medication use and other factors, including age, stroke onset to admission interval, length of rehabilitation stay, cause of stroke, and admission National Institutes of Health Stroke Scale score, therapeutic anticoagulation gave strong protection against VTE (OR=.37; 95% CI,.15-.88), followed by heparin (OR=.48; 95% CI,.23-.98) but not by antiplatelet agents (OR=.79; 95% CI,.40-1.57). No medications were associated with significant bleeding complications.

CONCLUSIONS

Use of therapeutic anticoagulants or prophylactic heparin prevented VTE in stroke patients during inpatient rehabilitation.

Risks of acute hospital transfer and mortality during stroke rehabilitation

OBJECTIVE

To identify demographic, medical, and functional factors associated with transfer of stroke patients to acute hospital services and/or mortality during stroke rehabilitation.

DESIGN

Two case-control studies in which logistic regression was used to control for clinical traits associated with differences in likelihood.

SETTING

A total of 542 US inpatient and rehabilitation units.

PARTICIPANTS

A total of 64,471 patients discharged during 1995.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Transfer to an acute hospital service and death.

RESULTS

There were 5847 (9.1%) acute hospital transfers and 320 (0.5%) deaths. Greater disability at admission was associated with higher odds of both acute hospitalization and mortality. Cardiopulmonary arrest, chest pain, gastrointestinal problems, bleeding disorders, hypercoagulable states, and acute renal difficulties increased the relative odds of acute hospitalization from 3.1 (95% confidence interval [CI], 2.3-4.2) to 12.7 (95% CI, 9.2-17.6). The likelihood of mortality for patients 85 years of age or older was more than 2-fold (2.5; 95% CI, 1.7-3.6) that of patients 65 years of age or younger for blacks, it was nearly 2-fold (1.7; 95% CI, 1.3-2.3) compared with whites, after adjusting for clinical differences.

CONCLUSION

Higher likelihoods of mortality among older patients versus younger, black patients versus white, and patients with more rather than less disability at admission suggest the need for greater vigilance in monitoring medical status.

Stroke rehabilitation. 2. Co-morbidities and complications

This self-directed learning module highlights new advances in the understanding of co-morbid conditions and medical complications of stroke. It is part of the chapter on stroke rehabilitation in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This article covers co-morbid conditions of stroke patients, including cardiovascular disease, diabetes, and sleep apnea. It reviews recent information on complications of stroke, including deep venous thrombosis, dysphagia and aspiration, hospital-acquired infections, depression, falls, spasticity, shoulder pain, and seizures. Treatment advances in diabetes, depression, and spasticity are highlighted. Recent information is presented regarding exercise guidelines for the stroke patient with cardiovascular disease, the relationship between stroke and sleep apnea, prophylaxis of deep venous thrombosis, the changing spectrum of hospital-acquired infections, malnutrition in stroke patients, the problem of falls during rehabilitation, the evaluation and management of poststroke shoulder pain, and the risk of seizures after stroke.

New developments in managing transient ischemic attack and acute stroke

During this decade, which has been designated the decade of the brain, the event of transient ischemic attack (TIA) or acute ischemic stroke is considered a brain attack requiring rapid diagnosis and treatment. This increased focus on the clinical problems of TIA and stroke has resulted in rapid advances in management of this patient population. This article will highlight for critical care nurses some of the many advances in patient management of TIA and stroke that have occurred in the past few years. Advances in the areas of diagnostic studies, pharmacologic interventions, and nursing care will be covered. Furthermore, some of the new developments on the horizon will be summarized.