No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
The wheelchair thrombosis syndrome
Abstract
To report a case of deep vein thrombosis (DVT) related to prolonged wheelchair use.
A 48-year-old patient with spastic quadriplegia usually spent 10-12 hours daily in a wheelchair. He suddenly developed marked swelling of his right foot, leg and thigh. His plasma D-dimer level was 1,030 (normal <500) ng/ml. A duplex ultrasound revealed common femoral vein thrombosis. He was hospitalized and anticoagulated; his extremity swelling decreased considerably by day 45. Hypercoagulability work-up disclosed previously subclinical mild elevation of serum cardiolipin immunoglobulin G (antiphospholipid syndrome). This patient will receive longterm anticoagulation.
Prolonged sitting in wheelchair may cause DVT. To enhance public recognition of this avoidable risk, we propose the term "wheelchair thrombosis syndrome."
... The potential interference from other reducing components that coexist in serum samples was also studied. As previously reported, the normal ranges of AA, Cys, GSH, Glu, urea, and DA in human serum samples are 34-114 µM [43], 5.0-15 µM [44], 0.26-0.34 mg mL −1 [45], 3.6-6.1 mM [46], 2.0-7.1 mM [47], and 0-888 pM [48], respectively. ...
In this work, we report a novel use of the distinctive metal-to-ligand charge-transfer (MLCT) absorption properties of the chromogenic Fe(BPDS)3⁴⁻ (BPDS = bathophenanthroline disulfonic acid) reporter for the visual detection of β-galactosidase (β-Gal) activity and sandwich immunoassay. The enzymatic hydrolysis of the substrate p-aminophenyl-β-D-galactopyranoside can switch on the reduction of Fe³⁺ to Fe²⁺ and the subsequent complexation of Fe²⁺ with the BPDS ligand to generate the Fe(BPDS)3⁴⁻ reporter, leading to the appearance of the intense MLCT absorption band at 535 nm and the colorless-to-red color change of the solution. Simply through a single step, the activity of β-Gal can be sensitively and selectively detected within the dynamic range of 0−220 mU mL⁻¹, with a limit of detection (LOD) of 1.69 mU mL⁻¹. This approach is applicable for the visual detection of β-Gal activities in the presence of complex human serum samples. Besides, when integrated with the sandwich immunoassay of carcinoembryonic antigen, a LOD of 1.16 ng mL⁻¹ can be achieved. In light of its prominent simplicity and practicality, our MLCT-based approach holds great potential in diagnostic and analytical applications.
... To demonstrate the interference immunity of our approach, the possible influence of other reducing interferents that coexist in serum samples on its colorimetric responses was investigated. The normal ranges of glucose, AA, urea, glutathione, cysteine, and dopamine in human serum samples are not higher than 6.1 mM [53], 114 mM [54], 7.1 mM [55], 0.34 mg mL À1 [56], 15 mM [57], and 888 pM [58], respectively. In our proof-of-concept experiments, the concentration of glucose, AA, urea, glutathione, cysteine, and dopamine were chosen as 6.5 mM, 120 mM, 7.5 mM, 0.4 mg mL À1 , 17 mM, and 1.0 nM, respectively. ...
We report a versatile approach for the colorimetric assay of alkaline phosphatase (ALP) activity based on the distinctive metal-to-ligand charge-transfer (MLCT) absorption properties of Fe(II)-phenanthroline reporter. In the presence of ALP, the applied substrate ascorbic acid 2-phosphate is enzymatically hydrolyzed to produce ascorbic acid, which then reduces Fe³⁺ to Fe²⁺. The complexation of Fe²⁺ with the bathophenanthroline disulfonate (BPS) ligand generates a blood-red Fe(BPS)3⁴⁻ reporter, which is characterized by an intense MLCT absorption band at 535 nm in the visible range. Under optimal conditions, the spectral output exhibits a good quantitative relationship with ALP activity over the range of 0–220 mU mL⁻¹ with a detection limit of 0.94 mU mL⁻¹. Moreover, the activity of ALP can also be conveniently judged through naked-eye observations. Results indicate that it is highly selective and can be applied to the screening of ALP inhibitors. In addition, it has been successfully employed to detect the endogenous ALP level of undiluted human serum samples, with a detection limit of 1.05 mU mL⁻¹ being achieved. This approach avoids any elaborately designed substrates and holds considerable simplicity and flexibility for reporter design. This study broadens the horizon of the applications of phenanthroline-based transition metal complexes. Furthermore, an efficient and practical method like this has the potential to be widely used in clinical applications and in the point-of-care testing.
Girls and young women with cerebral palsy face more difficulties than their nondisabled peers. In particular, reproductive health issues can be more complicated for adolescents with disabilities. This can be an area of significant apprehension and frustration for young women and their families. Medical providers often have limited training and comfort caring for young women with disabilities, especially with gynecologic issues in this population. As a result, adolescents with disabilities, and with cerebral palsy in particular, are less likely to receive education about reproductive health. In addition, confidentiality, a key tenet of adolescent health care, is often overlooked in this population. This chapter aims to provide education about reproductive health for young women with cerebral palsy, with a focus on menstrual management and contraceptive options.
Advanced age, obesity, and muscle weakness are independent factors in the onset of deep vein thrombosis (DVT). Recently, an association between sarcopenia and DVT has been reported. We hypothesized that sarcopenia related factors, observed by ultrasonography, are associated with the regression effect on the thrombus following anticoagulation therapy. The present study focused on gastrocnemius muscle (GCM) thickness and the GCM's internal echogenic brightness. We examined the association with DVT regression following direct oral anticoagulants (DOACs) treatment.
The prospective cohort study period was between October 2017 and August 2018. We enrolled 46 patients diagnosed with DVT by ultrasonography, who were aged >60 years old and treated with DOACs. Sarcopenia was evaluated using the Asian Working Group for Sarcopenia flowchart. The average DOACs treatment period was 94 days, and 29 patients exhibited thrombus regression. On univariate logistic regression analysis, sarcopenia, average GCM diameter index, and gastrocnemius integrated backscatter index were significantly associated with thrombus regression. In a multivariate model, only the average GCM diameter index correlated with thrombus regression.
The average GCM diameter index is associated with DVT regression treated with DOACs. Considering the GCM diameter during DVT treatment can be a marker to make a decision for the treatment of DVT.
The ability to directly detect alkaline phosphatase (ALP) activity in undiluted serum samples is of great importance for clinical diagnosis. In this work, we report the use of the distinctive metal-to-ligand charge-transfer (MLCT) absorption properties of the Cu(BCA)2⁺ (BCA = bicinchoninic acid) reporter for the visual detection of ALP activity. In the presence of ALP, the substrate ascorbic acid 2-phosphate (AAP) can be enzymatically hydrolyzed to release ascorbic acid (AA), which in turn reduces Cu²⁺ to Cu⁺. Subsequently, the complexation of Cu⁺ with the BCA ligand generates the chromogenic Cu(BCA)2⁺ reporter, accompanied by a color change of colorless-to-purple of the solution with a sharp absorption band at 562 nm. The underlying MLCT-based mechanism has been demonstrated on the basis of density functional theory (DFT) calculations. Needless of any sequential multistep operations and elaborately designed colorimetric probe, the proposed MLCT-based method allows for a fast and sensitive visual detection of ALP activity within a broad linear range of 20 – 200 mU mL⁻¹ (R² = 0.999), with a detection limit of 1.25 mU mL⁻¹. The results also indicate that it is highly selective and has great potential for the screening of ALP inhibitors in drug discovery. More importantly, it shows a good analytical performance for the direct detection of the endogenous ALP levels of undiluted human serum samples. Owing to the prominent simplicity and practicability, it is reasonable to conclude that the proposed MLCT-based method has a high application prospect in clinical diagnosis.
Fullsize Image
Disabilities are common in children and adolescents with >5% of children and adolescents affected by a physical or intellectual disability. The onset and progression through puberty may be challenging for girls with mental and physical disabilities and their families and caregivers. Gynecologic care may be underutilized in adolescents with disabilities, but pediatricians and pediatric and adolescent gynecologists should use a nonjudgmental approach, incorporating anticipatory guidance regarding pubertal changes and options for menstrual regulation, confidential care with the adolescent, and attention to parental concerns. Menstrual regulation can be useful to reduce symptoms of dysmenorrhea, reduce irregular menstrual bleeding, and decrease the frequency or amount of menstrual breeding. Options for menstrual regulation include combined hormonal contraceptives (available in pill, patch, and vaginal rings), progesterone-only contraceptives (including pills, injectables, implants, and IUDs), NSAIDs, and, as a last resort, surgical intervention. The ability to give consent for consensual sexual activity should be assessed in patients with disabilities. Adolescents with disabilities are at higher risk for sexual abuse and should receive sexual abuse prevention education at an appropriate level for their intellectual abilities.
The relationship between thyroid function and risk of venous thromboembolism (VTE) has not been addressed in population-based cohorts. We investigated the association between thyroid stimulation hormone (TSH) levels and risk of VTE in a general adult population.
Population-based cohort study Methods: TSH was measured in 11962 subjects, aged 25-89 years, who participated in Tromsø 4-6, starting in 1994-95. Incident VTE events were recorded through December 31, 2010. Cox`s regression models with TSH as time-varying exposure were used to calculate hazard ratios (HR) of VTE by TSH categories (<0.05 mU/L: low TSH, 0.05-0.19 mU/L: moderately reduced TSH, 0.20-4.00 mU/L: normal TSH, 4.01-5.00 mU/L: moderately elevated TSH, and >5.00 mU/L: high TSH), and within the normal range of TSH modelling TSH as a continuous variable.
There were 289 VTEs during 8.2 years of median follow-up. Subjects with low (prevalence: 0.22%) and high (3.01%) TSH had slightly higher risk estimates for VTE than subjects with normal TSH (multivariable HRs: 2.16, 95% CI 0.69-6.76 and 1.55, 95% CI 0.87-2.77, respectively), but the confidence intervals were wide. Moreover, there was no association between TSH within the normal range and VTE (HR per 1mU/L increase: 0.95, 95% CI: 0.82-1.11).
Serum levels of TSH within the normal range were not associated with risk of VTE, whereas low and high TSH levels were rare and associated with a moderate higher risk of VTE. Our findings suggest that only a minor proportion of the VTE risk in the population can be attributed to thyroid dysfunction.
Most obstetrician-gynecologists will encounter adolescents with disabilities in their practice, because developmental and physical disabilities are common in young patients (8.4%). Reproductive health issues such as puberty, sexuality, and menstruation can be more complicated for teenagers with disabilities and their families as a result of concerns surrounding menstrual hygiene, abuse risk, vulnerability, changes in seizure pattern, and altered mood. Teenagers with disabilities have gynecologic health care needs similar to those of their peers as well as unique needs related to their physical and cognitive issues. The gynecologic health visit for a teenager with disabilities should include an evaluation of the teenager's reproductive knowledge as well as an assessment of her abuse and coercion risk and her ability to consent to sexual activity. The menstrual history is focused on the effects of menstrual cycles on her daily life. Diagnostic testing is not different from other adolescents. Hormonal treatment is often requested by the patient and her family to alleviate abnormal bleeding, cyclic mood changes, dysmenorrhea, or a combination of these, to assist with menstrual hygiene, and to provide contraception. Menstrual manipulation can be used to induce complete amenorrhea, regulate cycles, or decrease regular menstrual flow. However, treatment risks and side effects may have a different effect on the lives of these adolescents. The comfort level of health care providers to respond to the special concerns of adolescents with disabilities is low, and several barriers exist. This review addresses the complex issues of puberty, menstruation, sexuality, abuse, and safety highlighting the distinctive needs of this population. The options and decisions around menstrual manipulation are highlighted in detail.
Background
Glycated hemoglobin (HbA1c), a marker of average plasma glucose during the last 8-12 weeks, is associated with future risk of cardiovascular disease (CVD) and all-cause mortality. Objectives
To examine the association between hyperglycemia, assessed by HbA1c, and future risk of VTE in a population based cohort. Methods
HbA1c was measured in 16 156 unique subjects (25-87 years) who participated in one or more surveys of the Tromsø study (Tromsø 4; 1994-95, Tromsø 5; 2001-2, and Tromsø 6; 2007-8). All subjects were followed, and incident VTE events were recorded through December 31, 2010. ResultsThere were 333 validated first VTE events, of which 137 were unprovoked, during a median follow-up of 7.1 years. HbA1c was not associated with future risk of VTE in analysis treating HbA1c as a continuous variable, or in categorized analyses. The risk of VTE increased by 5% per 1 SD (0.7%) increase in HbA1c (multivariable-adjusted HR 1.05; 95% CI 0.97-1.14), and subjects with HbA1c ≥ 6.5% had 27% higher risk compared to those with HbA1c below 5.7% (multivariable-adjusted HR 1.27; 95% CI 0.72-2.26). There was no significant linear trend for increased risk of VTE across categories of HbA1c (p=0.27). Conclusions
Serum levels of HbA1c were not associated with future risk of VTE in multivariable analysis. Our findings suggest that hyperglycemia does not play an important role in the pathogenesis of VTE.This article is protected by copyright. All rights reserved.
To assess the potential impact of controlling risk factors on the incidence of venous thromboembolism by estimating the population attributable risk (defined as the percentage of all cases of a disease in a population that can be "attributed" to a risk factor) for deep vein thrombosis and pulmonary embolism associated with venous thromboembolism risk factors.
Using data from a population-based, nested, case-control study of the 625 Olmsted County, Minnesota, residents with a definite first lifetime deep vein thrombosis or pulmonary embolism diagnosed during the 15-year period 1976 to 1990 and 625 unaffected Olmsted County residents matched for age and sex, we developed a conditional logistic regression model appropriate to the matched case-control study design and then estimated attributable risk for the risk factors individually and collectively.
Fifty-nine percent of the cases of venous thromboembolism in the community could be attributed to institutionalization (current or recent hospitalization or nursing home residence). Hospitalization for surgery (24%) and for medical illness (22%) accounted for a similar proportion of the cases, while nursing home residence accounted for 13%. The individual attributable risk estimates for malignant neoplasm, trauma, congestive heart failure, central venous catheter or pacemaker placement, neurological disease with extremity paresis, and superficial vein thrombosis were 18%, 12%, 10%, 9%, 7%, and 5%, respectively. Together, the 8 risk factors accounted for 74% of disease occurrence.
Factors associated with institutionalization independently account for more than 50% of all cases of venous thromboembolism in the community. Greater emphasis should be placed on prophylaxis for hospitalized medical patients. Other recognized risk factors account for about 25% of all cases of venous thromboembolism, while the remaining 25% of cases are idiopathic.
New clinical, laboratory and experimental insights, since the 1999 publication of the Sapporo preliminary classification criteria for antiphospholipid syndrome (APS), had been addressed at a workshop in Sydney, Australia, before the Eleventh International Congress on antiphospholipid antibodies. In this document, we appraise the existing evidence on clinical and laboratory features of APS addressed during the forum. Based on this, we propose amendments to the Sapporo criteria. We also provide definitions on features of APS that were not included in the updated criteria.
Deep vein thrombosis (DVT) is a serious health problem that affects more than 2 million people annually in the United States. Many of these patients develop asymptomatic DVT, but months to years later may experience symptomatic post-thrombotic syndrome (PTS). It is not known how many cases of PTS can be traced to "asymptomatic" DVT because venography is no longer routinely done and ultrasonography (US) may miss some asymptomatic clots. As a result, a clinical tool in addition to US to detect symptom emergence or exacerbation in patients after DVT would be of value.
Seventy-seven patients hospitalized with an acute DVT interviewed by telephone at 3-7 days, 30-40 days, and 12-months following discharge were included in this report. All were treated with a standard anticoagulation "Clinical Pathway Protocol" between April 1999 and January 2000. Using a 14-item Deep Vein Thrombosis Leg Symptom Index (DVT-LSI), patients were queried regarding leg pain, swelling, skin discoloration, cosmetic appearance, activity tolerance, emotional distress, and leg-related sleep problems.
The DVT-LSI for each leg was reliable at all assessments, with instrument reliability (alpha coefficients) greater than 0.70 at all time points (range 0.71-0.87). DVT-LSI scores, and the percentage of patients exhibiting symptoms, were higher in the DVT-affected leg at all time points. Among patients with unilateral disease, symptom severity ratings were significantly worse for patients in the affected leg compared to the normal leg at all time points, with the exception of those with a right-leg DVT at 12 months. Patients with bilateral thrombi did not have different scores on one leg compared to the other.
The DVT-LSI is useful in assessing symptomatic clinical outcomes in patients after diagnosis of DVT, and may represent a surrogate marker for DVT otherwise presumed to be asymptomatic.
To review the validity of the clinical assessment and diagnostic tests in patients with suspected deep vein thrombosis (DVT).
A comprehensive review of the literature was conducted by searching MEDLINE from 1966 to April 1997.
Individual symptoms and signs alone do not reliably predict which patients have DVT. Overall, the diagnostic properties of the clinical examination are poor; the sensitivity of the clinical examination ranges from 60% to 96%, and the specificity ranges from 20% to 72%. However, using specific combinations of risk factors, symptoms, and physical signs for DVT, clinicians can reliably stratify patients with suspected DVT into low, moderate, or high pretest probability categories of actually suffering from DVT. This stratification process in combination with noninvasive testing, such as compression ultrasonography, simplifies the management strategies for patients with suspected DVT.
Use of a clinical prediction guide that includes specific factors from both the history and physical examination in combination with noninvasive tests simplifies management strategies for patients with suspected DVT.
Pulmonary thromboembolism developed in eight patients shortly after travel. Preexisting vein disease was present in this group. Possible prophylactic measures are suggested.
The presentation of pulmonary embolism is variable in the elderly as in any age group. Common symptoms such as chest pain, dyspnea, and hemoptysis may be absent. Furthermore, precursors such as phlebitis, malignancy, and recent surgery often may be absent as well. Our intent was to examine the occurrence in a long-term care institution of pulmonary embolism at autopsy and the extent of missed antemortem diagnosis of this condition, and to compare patients with and without pulmonary embolism by chart and autopsy review. The incidence of pulmonary embolism in our study of elderly patients during a six-year period in a teaching nursing home was 12.8%. Although our series is small, consisting of 47 autopsies, our results are in accord with reports from other patient sites. Few autopsies are performed on nursing home patients and even fewer have been studied with regard to the occurrence and characteristics of pulmonary embolism in this population. The diagnosis remains difficult and uncertain, especially so in the elderly, because of the variability of presentation and association, the lesser pursuit of aggressive or invasive diagnostic methods, and the paucity of postmortem documentation.
In this study to determine the incidence of deep vein thrombosis (DVT) in spinal cord injury (SCI) patients, we evaluated 30 instances of bilateral ascending venography obtained in 31 patients. Every patient was on prophylactic low dose heparin anticoagulant therapy. The incidence of DVT was found to be 53.3%. Adverse effects due to venography were seen in 10% of patients. No major complications including postvenographic phlebitis and allergic reactions were observed.
We have previously demonstrated that a clinical model can be safely used in a management strategy in patients with suspected pulmonary embolism (PE). We sought to simplify the clinical model and determine a scoring system, that when combined with D-dimer results, would safely exclude PE without the need for other tests, in a large proportion of patients. We used a randomly selected sample of 80% of the patients that participated in a prospective cohort study of patients with suspected PE to perform a logistic regression analysis on 40 clinical variables to create a simple clinical prediction rule. Cut points on the new rule were determined to create two scoring systems. In the first scoring system patients were classified as having low, moderate and high probability of PE with the proportions being similar to those determined in our original study. The second system was designed to create two categories, PE likely and unlikely. The goal in the latter was that PE unlikely patients with a negative D-dimer result would have PE in less than 2% of cases. The proportion of patients with PE in each category was determined overall and according to a positive or negative SimpliRED D-dimer result. After these determinations we applied the models to the remaining 20% of patients as a validation of the results. The following seven variables and assigned scores (in brackets) were included in the clinical prediction rule: Clinical symptoms of DVT (3.0), no alternative diagnosis (3.0), heart rate >100 (1.5), immobilization or surgery in the previous four weeks (1.5), previous DVT/PE (1.5), hemoptysis (1.0) and malignancy (1.0). Patients were considered low probability if the score was <2.0, moderate of the score was 2.0 to 6.0 and high if the score was over 6.0. Pulmonary embolism unlikely was assigned to patients with scores < or =4.0 and PE likely if the score was >4.0. 7.8% of patients with scores of less than or equal to 4 had PE but if the D-dimer was negative in these patients the rate of PE was only 2.2% (95% CI = 1.0% to 4.0%) in the derivation set and 1.7% in the validation set. Importantly this combination occurred in 46% of our study patients. A score of <2.0 and a negative D-dimer results in a PE rate of 1.5% (95% CI = 0.4% to 3.7%) in the derivation set and 2.7% (95% CI = 0.3% to 9.0%) in the validation set and only occurred in 29% of patients. The combination of a score < or =4.0 by our simple clinical prediction rule and a negative SimpliRED D-Dimer result may safely exclude PE in a large proportion of patients with suspected PE.
A 5-year-old with spastic quadraparetic cerebral palsy suffered multiple strokes after extensive orthopedic surgery. Coagulation testing was undertaken to determine whether a familial thrombophilia was present. The patient was found to be heterozygous for factor V Leiden. Factor V Leiden may be a risk factor for central nervous system events in special-needs children, particularly when common medical conditions create additional procoagulant risks.
The risk factors and incidence of deep venous thrombosis were studied in a population of para- and tetraparesic patients institutionalized for long durations.
Retrospectively, the antecedents and risk factors of deep venous thrombosis were collected for each patient.
Data were available for 57 patients. The mean duration of hospitalization was 18 years. None of the patients presented thromboembolic pathology. Ninety-three per cent of the patients were spastic tetraparesic, 7% were spastic paraparesic. Sixty per cent of the patients presented added risk factors, mostly orthopaedic surgery, bone fractures and hormonal treatments.
Spasticity probably plays a role in preventing deep venous thrombosis in paralysed patients, but it does not fully explain the absence of deep venous thrombosis in this population.
In gynaecology, women are exposed to sex steroids when using oral contraceptives, hormone replacement therapy or when undergoing in vitro fertilization treatment and ovulation induction. Oral contraceptives and the use of hormone replacement therapy increase the risk of venous thrombosis. The risk is highest in the first year of use and higher among women with clotting defects. Women taking third-generation oral contraceptives have an almost twofold increased risk of venous thrombosis compared with those taking second-generation oral contraceptives. Inherited clotting defects, which are themselves risk factors of venous thrombosis, (e.g. factor V Leiden mutation, deficiency of protein C, protein S or antithrombin, high plasma levels of factor VIII, and prothrombin mutation) appear synergistically increase the risk of venous thrombosis caused by oral contraceptives. Recent studies also point to an interaction between hormone replacement therapy and coagulation defects in causing venous thrombosis. Emerging studies show that in vitro fertilization treatment and ovulation induction are also risk factors for venous thrombosis; the role of coagulation defects in this association is not yet clear.
To describe a cluster of cases of proximal deep vein thrombosis among nursing home residents treated with megestrol acetate, to identify other risk factors for deep vein thrombosis development among these patients, and to alert physicians to this potential complication of megestrol acetate therapy.
Retrospective review.
A 129-bed Maryland nursing home.
Nineteen residents prescribed megestrol acetate between November 1997 July 1998, identified by computerized pharmacy records.
Demographic data (including identification of known risk factors for deep vein thrombosis development) were collected along with information on the indications for megestrol acetate therapy and its duration, diagnostic studies related to detection of deep vein thrombosis and their results, and patient outcomes following diagnosis of deep vein thrombosis.
Megestrol acetate was prescribed for 18 nutritionally at-risk patients and one with uterine cancer. Six (32%) patients developed deep vein thrombosis signs and symptoms, and all diagnoses were confirmed as proximal deep vein thromboses with Doppler studies. (No diagnosis of deep vein thrombosis were made among any nursing home patients not being treated with megestrol acetate during the observation period.) All patients diagnosed with deep vein thrombosis were hospitalized and anticoagulated, but none were diagnosed with pulmonary embolus or died. The length [median (range)] of megestrol acetate treatment was similar regardless of whether deep vein thrombosis developed [117 (57-244) versus 143 (2-294) days, respectively, P = 0.83]. Stratification by length of treatment in 50-day increments revealed that most patients who developed deep vein thrombosis did so after 50 days of treatment (P = 0.046).
A high incidence of deep vein thrombosis was identified among nursing home residents treated with megestrol acetate, even among ambulatory individuals with no other known risk factors. Because the efficacy of megestrol acetate treatment in nursing home residents with weight loss is unproven, the risk of deep vein thrombosis must be considered when prescribing megestrol acetate, and its use to treat nutritionally at-risk nursing home residents should be limited.
The frequency and role of risk factors for venous thromboembolism related to air travel is uncertain. We aimed to establish the frequency of this disorder in a group of long distance air travellers and to investigate the role of potential risk factors.
We designed a prospective study into which we recruited individuals aged between 18 and 70 years, travelling for 4 h or more by aircraft. D-dimer measurement was done before and after travel. Participants with a negative D-dimer (<500 ng/L) before travel were included in the study. Those who became D-dimer positive or developed high clinical probability symptoms during the 3 months after travel were investigated with bilateral compression ultrasonography and CT pulmonary angiography. Suspected clinical and thrombophilic risk factors, and use of prophylactic measures, were assessed.
1000 individuals were recruited, with 878 meeting inclusion criteria and completing the study. All participants travelled at least 10 h, with a mean total duration of air travel of 39 h (SD 12.5). 112 patients underwent radiological assessment on return. Frequency of venous thromboembolism associated with travel was 1.0% (9/878, 95% CI 0.5-1.9), which included four cases of pulmonary embolism and five of deep venous thrombosis. Six patients with venous thromboembolism had pre-existing clinical risk factors, two had a recognised thrombophilic risk factor, two travelled exclusively in business class, five used aspirin, and four wore compression stockings.
Our results suggest an association between multiple long distance air flights and venous thromboembolism, even in individuals at low to moderate risk. The role of traditional risk factors and prophylactic measures in air travel-related venous thromboembolism needs further investigation.
A dangerous type of spontaneous venous thrombosis in the legs was seen in six men, during a two-year period. All of these men were over 6 ft. (182.88 cm.) tall, and four of them were 6 ft. 2 in. (187.96 cm.) or more. In none of these patients did the venous thromboses follow surgical operations, but in each case they appeared after severe physical strain or for no apparent reason. In all of the many other patients seen with thrombophlebitis over the same two-year period, the thromboses occurred either postoperatively or post-partum, or as a result of malignancy, prolonged illness, or involved superficial varicose veins.
In three of the tall patients pulmonary infarction was the first symptom, and five required either iliac or femoral vein ligation. All six of these patients had, initially or eventually, bilateral involvement. Two of the patients had pulmonary emboli while receiving anticoagulants, and a third
To determine the prevalence and risk factors of deep vein thrombosis (DVT) among neurorehabilitation admissions with acquired brain injury (BI).
In this prospective, sequential case series, 709 consecutive initial neurorehabilitation patients with BI < 120 days-including traumatic brain injury (TBI; n = 360), intracranial hemorrhage (ICH; n = 213), primary brain tumor (n = 66), and hypoxia/other BI (n = 70)--were screened for evidence of DVT with lower extremity venous duplex ultrasonography (VDU). The admission screening protocol combined VDU and a commercial d-dimer (Dimertest [DDLx]) latex agglutination assay. DVT was considered present based upon VDU results only.
DVT prevalence was 11.1%, and was higher with brain tumor (21.2%) and ICH (16%) than with TBI (6.7%) (chi2 test; p = 0.001). DVT risk factors identified by multivariable logistic regression analysis in the overall sample included older age (p = 0.002), type of BI (p = 0.04), DDLx (p = 0.0001), and greater postinjury duration (p = 0.0001), with a trend observed regarding lower Functional Independence Measure (FIM) locomotion (FIM-Loco) subscale score (p = 0.07). However, risk factors also varied with type of BI. Among patients with TBI, only DDLx (p = 0.001) and greater postinjury duration (p = 0.001) were associated with DVT.
Admission venous duplex ultrasonography revealed occult proximal lower extremity deep vein thrombosis in 11% of neurorehabilitation patients with acquired brain injury. Deep vein thrombosis risk is multifactorial in this heterogenous patient population, with relative factor risk influenced by type of acquired brain injury. Semiquantitative d-dimer latex agglutination assay correlated significantly with presence of deep vein thrombosis.
Risk factors for deep venous thrombosis in tetraparesic mentally retarded patients Vascular diseases of extremities Harrison's Principles of Internal Medicine Deep vein thrombosis: prevalence and rsk factors in rehabilitation admissions with brain injury
- M Rousseau
- B B Guillotel
- M Creager
- Dzau
- D Kasper
- E Braunwald
- A Fauci
Rousseau M, Guillotel B. Risk factors for deep venous thrombosis in tetraparesic mentally retarded patients. Brain Inj. 2001;15:1041-1044. B. Creager M, Dzau V. Vascular diseases of extremities. In: Kasper D, Braunwald E, Fauci A, et al, eds. Harrison's Principles of Internal Medicine. 16th ed. New York: McGraw Hill; 2005;chapter 232:1486-1494. 9. Yablon S, Rock W, Nick T. Deep vein thrombosis: prevalence and rsk factors in rehabilitation admissions with brain injury. Neurology. 2004;63:485-491.
Deep vein thrombosis: validation of a patient reported leg symptom index Health Qual Life Outcomes Postoperative stroke in a child with cerebral palsy heterozygous for factor V Leiden
- S Hudgens
- Cella
- M Steiner
- M Hodes
- M Shreve
- S Sundberg
- J Edson
Hudgens S, Cella D. Deep vein thrombosis: validation of a patient reported leg symptom index. Health Qual Life Outcomes. 2003;1:76-88. 10. Steiner M, Hodes M, Shreve M, Sundberg S, Edson J. Postoperative stroke in a child with cerebral palsy heterozygous for factor V Leiden. J Pediatric Hematol Onco. 2000;22:262-264.
Vascular diseases of extremities Harrison's Principles of Internal Medicine
- B Creager
- M Dzau
- V Kasper
- D Braunwald
- E Fauci
B. Creager M, Dzau V. Vascular diseases of extremities. In: Kasper D, Braunwald E, Fauci A, et al, eds. Harrison's Principles of Internal Medicine. 16th
ed. New York: McGraw Hill; 2005;chapter 232:1486-1494.
Venous and lymphatic disease Schwartz's Principles of Surgery
- E Lam
- M Giswold
- G Moneta
Lam E, Giswold M, Moneta G. Venous and lymphatic disease. In: Brunicardi F, Andersen D, Billiar T, et al, eds. Schwartz's Principles of Surgery. 8th
ed. New York: McGraw Hill; 2005;809-833.