Venous Stasis,Deep Venous Thrombosis and Airline Flight: Can the Seat be Fixed?

Deep venous thrombosis (DVT) and pulmonary embolization (PE) associated with air travel are directly related to the duration of flight and seating in non-aisle seats. In this study, we assessed a modification of a standard airline seat (NewSit) designed to decrease the incidence of DVT on long flights. This seat raises the feet from the floor, facilitates mobility, and permits intermittent calf compression. Air plethysmography (APG) was used to measure the ejected venous volume of the calves of 25 volunteers before and after sitting for 5 hours on the conventional and modified seats. The mean percent (+/- standard deviation [SD]) increase in venous volume for the conventional seat after 5 hours of continuous sitting was significantly greater than that for the modified seat (26.6 +/- 18.5% vs 3.5 +/- 13.1%, P < 0.0001 by paired, two-tailed t-test). Improvement (any) was seen in 23 of 25 patients, with 15 of the 23 (65%) being better than 1 SD of the mean (P < 0.0001 by Chi-square analysis). This study suggests that the leg movement and calf compression associated with the modified airline seat (NewSit) may decrease the probability of DVT due to prolonged periods of sitting by reducing venous stasis as measured by APG. Further studies involving a larger randomized patient cohort, as well as analysis of the effect of this modification on specific coagulation markers such as tissue plasminogen activator and fibrin D-dimer, are planned.     

Popliteal Venous Aneurysm—A Systematic Review

Background Popliteal vein aneurysm is a rare but potentially problematic disease with a risk of pulmonary embolism. Method A systematic literature search was performed. Results A total of 105 popliteal vein aneurysms were identified, with a slight female and left-sided preponderance. Dominating symptoms are caused by pulmonary embolism, followed by local symptoms with a palpable mass. In four patients arterial symptoms were reported. The most frequently used diagnostic test was phlebography, increasingly replaced by duplex ultrasonography in recent years. Because pulmonary embolism is a potential, it motivates surgical removal. In most cases excision and lateral suture is possible. Four fatal cases were reported. Unfortunately follow-up time and results are poorly documented. Conclusion Popliteal venous aneurysm is rare but should be considered as a local source of pulmonary embolism when no other explanation is found.     

Venous reconstructions using the superficial femoral–popliteal vein

Purpose: To demonstrate the feasibility of venous reconstructions with the superficial femoral–popliteal vein (SFPV).Methods: Seven patients who underwent a variety of major venous reconstructions using SFPV were reviewed in a retrospective, observational study.Results: Three central venous reconstructions (thoracic and abdominal) and four peripheral major venous reconstructions were performed with SFPV autografts. In all patients, the SFPV grafts provided an excellent size match and were of adequate length without the need for enlargement by paneling or spiraling techniques. Postoperative anticoagulation medication was not used. There were no early graft failures, and patency was documented by duplex ultrasound, venogram, or both in all patients at a mean of 20 months follow-up. Venous thromboembolism has not occurred, and lower extremity venous morbidity has been minimal.Conclusions: The SFPV graft demonstrates versatility and durability in selected patients who require large-caliber conduits for venous reconstruction. Because of its size and availability, the SFPV is an excellent conduit for major venous reconstruction. (J Vasc Surg 1997;26:829-37.)     

Presidential address to the 1998 American Venous Forum: Where are we now? Where are we going? Inching forward

J Vasc Surg 1998;28:761-6.     

Hepatic Portal Venous Gas: A Warning Sign!?

A case of an overwhelming amount of hepatic portal venous gas caused by intestinal ischemia is described.     

Venous thromboembolism in radical prostatectomy: is heparinoid prophylaxis warranted?

OBJECTIVE: To review the incidence of venous thromboembolism (VTE) after radical retropubic prostatectomy (RRP) and evaluate the need for heparinoid prophylaxis as opposed to mechanical compression devices after RRP. PATIENTS AND METHODS: RRP is classified as a category 1 (high risk) procedure for VTE by the American College of Chest Physicians and several international guidelines recommend subcutaneous heparinoids as the preferred prophylaxis. However, this regimen may be associated with a greater risk of bleeding. We have not used heparinoid prophylaxis but place a mechanical compression device for prophylaxis of VTE, and report our clinical experience over a 12-year period. Between 1992 and 2004, all RRPs carried out by one surgeon (M.S.S.) at our centre were retrospectively reviewed after obtaining institutional review board approval. The protocol for prophylaxis of VTE consisted of compression stockings and a sequential compression device from the time of entry into the operating room until complete ambulation (we encourage early ambulation). Patients were evaluated for VTE if they developed any clinical signs or symptoms. Patients were followed at 7 days, 6 weeks and 3 months after RRP in the first year and 6-monthly thereafter. All relevant clinical data and complications were entered in a database. RESULTS: In all there were 1364 RRPs; the mean (sd) age of the patients was 61 (7) years and the mean follow-up 44 (38) months. All patients had a mechanical compression device and ambulated on the first day after surgery. None received heparinoid prophylaxis. Three VTE events were identified (0.21%); two patients had a lower limb VTE and one an upper limb VTE. All were successfully treated with anticoagulation. No patient had a documented pulmonary embolus and none died from VTE. There was one death after RRP, from myocardial infarction. CONCLUSION: The incidence of VTE after RRP is low, possibly related to the use of a mechanical compression device and early aggressive mobilization. Despite the recommendations by some, we feel that routine heparinoid prophylaxis is questionable.     

Venous impulse foot pumps: should graduated compression stockings be used?

It is not known whether the effect of Foot Pumps (Novamedix, Andover, UK) is enhanced by simultaneous use of graduated compression stockings (by controlling calf compliance) or hindered (by restricting preload). To address this question, we studied 20 healthy volunteers with duplex ultrasound. The peak velocity in the popliteal vein was measured at rest with the legs flat, foot-up, and foot-down, then it was measured when the AV Impulse Foot Pump was activated. These measurements each were performed with and without graduated compression stockings. In each leg position, the use of simultaneous graduated compression stockings reduced the peak velocity. On physiologic grounds, graduated stockings should not be used simultaneously with Foot Pumps.     

Venous thromboembolic events in pediatric trauma patients: is prophylaxis necessary?

BACKGROUND: Venous thromboembolic events (VTE), such as deep vein thrombosis and pulmonary embolism, are major morbidities in adult trauma patients. Invasive and noninvasive prophylactic therapies are used to prevent VTE in trauma patients. The risk of VTE in pediatric patients is not well known. Is VTE prophylaxis necessary in the pediatric trauma population? METHODS: This is a retrospective study from the trauma registry of a Level I trauma center from January 1, 1994, through December 31, 2003. Three separate age groups were reviewed: Group I, age less than 13 years; group II, age 13 to 17 years; and group III, age greater than 17 years. Group I did not receive any VTE prophylaxis. All patients in group III received invasive and noninvasive prophylaxis if not contraindicated. In group II, VTE prophylaxis was administered at the preference of the attending surgeon. All patients were assigned an Injury Severity Score at discharge. RESULTS: A total of 13,880 patients were identified. Groups I, II, and III had 1,192; 1,021; and 10,568 patients, respectively. In group I, no patient developed a VTE. Two patients in group II developed VTE. Both had an Injury Severity Score of >24 and both had contraindication to invasive prophylaxis. In group III, 59 patients developed VTE. CONCLUSION: The risk of clinically significant thromboembolic event in trauma patients under age 13 is negligible. Therefore, VTE prophylaxis is unnecessary in pediatric patients with traumatic injury.     

Venous thromboembolism in trauma: a local manifestation of systemic hypercoagulability?

BACKGROUND: The purpose of this study was to evaluate the relative importance of systemic hypercoagulability, preexisting and acquired risk factors, and specific injury patterns in the development of venous thromboembolism (VTE) after injury. METHODS: Injured patients with an Injury Severity Score > or = 15 were followed with lower extremity venous duplex ultrasonography, prothrombin fragment 1 + 2, and quantitative D-dimer levels at 1 and 3 days and then weekly until discharge. RESULTS: Among 101 patients with a mean Injury Severity Score of 27.3 +/- 10.5 followed for 12.4 +/- 8.7 days, 28 (27.7%) developed a lower extremity thrombosis, 2 (1.9%) sustained a pulmonary embolism, and 1 (0.9%) had a symptomatic upper extremity thrombosis. Although admission fragment 1 + 2 and D-dimer levels were elevated in 81.4% and 100% of patients, respectively, mean levels were not significantly different in those with or without VTE. VTE was more common (p < 0.05) among those with obesity, age > 40 years, immobilization for > 3 days, spine fractures, and lower extremity fractures. However, only obesity (p = 0.004) and immobilization > 3 days (p = 0.05) were independent predictors of VTE in a multivariate analysis. CONCLUSION: Although elevated in seriously injured patients, neither markers of activated coagulation nor specific injury patterns are predictive of VTE. Associations with immobilization and obesity suggest that VTE after injury is a systemic hypercoagulable disorder with local manifestations of thrombosis related to lower extremity stasis.     

Venous ulcers of the lower limb: Where do we stand?

Venous ulcers are the most common ulcers of the lower limb. It has a high morbidity and results in economic strain both at a personal and at a state level. Chronic venous hypertension either due to primary or secondary venous disease with perforator paucity, destruction or incompetence resulting in reflux is the underlying pathology, but inflammatory reactions mediated through leucocytes, platelet adhesion, formation of pericapillary fibrin cuff, growth factors and macromolecules trapped in tissue result in tissue hypoxia, cell death and ulceration. Duplex scan with colour flow is the most useful investigation for venous disease supplying information about patency, reflux, effects of proximal and distal compression, Valsalva maneuver and effects of muscle contraction. Most venous disease can be managed conservatively by leg elevation and compression bandaging. Drugs of proven benefit in venous disease are pentoxifylline and aspirin, but they work best in conjunction with compression therapy. Once ulceration is chronic or the patient does not respond to or cannot maintain conservative regime, surgical intervention treating the underlying venous hypertension and cover for the ulcer is necessary. The different modalities like sclerotherapy, ligation and stripping of superficial varicose veins, endoscopic subfascial perforator ligation, endovenous laser or radiofrequency ablation have similar long-term results, although short-term recovery is best with radiofrequency and foam sclerotherapy. For deep venous reflux, surgical modalities include repair of incompetent venous valves or transplant or transposition of a competent vein segment with normal valves to replace a post-thrombotic destroyed portion of the deep vein.KEY WORDS: Compression therapy, surgery on veins, venous hypertension, venous ulcers Indian JouIn the course of a lifetime, almost 10% of the population will develop a chronic wound, with a wound-related mortality rate of 2.5%.[1] Of these, underlying venous pathology is the most common aetiology of lower extremity ulceration.[2] Even in the 21^st century, studies revealed the following effects of ulceration: pain, itching, altered appearance, loss of sleep, functional limitations, social isolation, depression and disappointment with treatment.[3,4] In 2011, an integrative review of previous studies on quality of life in patients with venous ulcers was published, which confirmed the negative impact of the disease on health-related quality of life.[5]Venous ulcers are the result of breakdown of skin due to failure of preventing the consequence of chronic venous insufficiency. The disease has been known for more than 3.5 millennia, with wound care centers established as early as 1500 BC. Unfortunately, still today, it is a very poorly managed clinical condition by most physicians despite acquiring a great deal of knowledge about the pathogenesis and treatment for venous ulcerations.[6]There is no available statistics related to the incidence of venous ulcers in India. But, an epidemiologic study on railway workers in 1972 found the incidence of varicose veins to be significantly higher in South Indians than in their northern counterparts.[7]The morbidity of the disease, inadequate management, necessary logistic support and prolonged continuous care makes this disease a financial burden both at a personal and at the Government level. In the US, 80% of the lower extremity ulcers are venous ulcers, and the financial burden is $2 billion per year.[8,9] Venous leg ulceration alone has been estimated to cost the NHS £400 m a year in the United Kingdom.[10] Studies in Germany calculated the mean total cost of a venous ulcer per patient per year to be €9569 (€8658-92% direct costs and €911-8% indirect costs).[11]     

Venous thromboembolism prophylaxis after general surgery: where are we now?

Venous thromboembolism (VTE) is a frequent complication in patients undergoing major surgery, with the possibility of long-term disability or fatal outcome. The rationale of the thromboprophylaxis in all patients can be summarized in three points: 1) the VTE is common in some types of surgery; 2) the VTE can be fatal; 3) thromboprophylaxis is highly effective and safe and, besides these clinical benefits, leads to lower total costs of treatment without further diagnostic and a new shelter for treating venous thrombosis. The surgical patients may present at admission one or more risk factors for VTE, The effect of this risk is cumulative, it is important to stratify the risk and to established an adequate prophylactic strategy. Today there is a unanimous consensus that the low molecular weight heparins are both effective and safe in preventing VTE in surgical patients. Unanimously approved guidelines can help surgeons in making decisions regarding VTE prophylaxis.     

Non-Insertion-Related Complications of Central Venous Catheterization—Temporary Vascular Access for Hemodialysis

The authors analyzed 309 central venous catheters (CVC) inserted in 147 hemodialysis patients before the maturation of the first or new arteriovenous fistula. One clinical manifestations of sepsis after CVC insertion was found. In all, 33.7% of the catheters were removed because of early minor complications: CVC occlusion, inadequate blood flow in CVC, shattered suture and malposition of CVC, fever, signs of infection at the site of CVC insertion, and bleeding at the site of CVC insertion. The most frequently isolated pathogenic bacteria at the tips of the catheters were coagulase-negative staphylococci highly sensitive to vancomycin and gentamicin.     

Venous thromboembolism after lower limb arthroplasty: is chemical prophylaxis still needed?

Background

Venous thromboembolism (VTE) is a significant complication of lower limb arthroplasty. The National Institute for Health and Care Excellence recommends routine use of chemical and mechanical prophylaxis to prevent VTE. Our high-volume, elective, arthroplasty unit adopted this guidance in 2008.

Purpose

We examined our incidence of VTE before and after introduction of chemical thromboprophylaxis to determine whether the incidence of VTE reduced.

Methods

We retrospectively gathered data on 2 cohorts of patients—from January 2004 to August 2007 (Group 1) and January 2010 to December 2012 (Group 2). Patients in Group 1 received mechanical prophylaxis only (unless particularly high risk for VTE), and patients in Group 2 received mechanical and chemical prophylaxis. We recorded VTE occurring within 6 months of surgery. Patients in Group 1 receiving chemical prophylaxis were excluded.

Results

Group 1 had 2320 cases of primary and revision lower limb arthroplasty, and Group 2 had 1430 cases. VTE occurred in 37 cases in Group 1 (1.6 %), and in 17 cases in Group 2 (1.2 %). This difference was not statistically significant (p = 0.26). In Group 1, 1 patient died within 6 months due to pulmonary embolism (0.04 %); there were no VTE-related deaths in Group 2 (0 %). This was also not statistically significant (p = 0.06).

Conclusions

Although our VTE rate reduced by 0.4 % and our VTE-related mortality reduced by 0.04 % after introduction of chemical thromboprophylaxis, these differences were not statistically significant. Chemical thromboprophylaxis may not be required in all patients undergoing arthroplasty providing appropriate mechanical prophylaxis is used.