Correspondence
Deep-Vein Thrombosis
N Engl J Med 1995; 332:1447-1448May 25, 1995
- Article
To the Editor:
The review of deep-vein thrombosis by Weinmann and Salzman (Dec. 15 issue)1 states that thromboembolic disease during pregnancy occurs primarily in the postpartum period. We disagree with this assertion. The risk of thromboembolic disease has traditionally been thought to be greatest in the postpartum period. However, more recent data refute this position. In an 11-year review of 93 cases of thromboembolic disease among 169,776 pregnant women, Rutherford and associates reported that 75 percent of cases of deep venous thrombosis occurred before delivery, with 51 percent occurring by 15 weeks of gestation.2 In another retrospective study, involving 30 women with objectively diagnosed venous thrombosis, the condition occurred in 22.2, 40.7, and 37.1 percent of the women during the first, second, and third trimesters, respectively.3 Ginsberg and colleagues have reported that the frequency of venous thrombosis was the same in all three trimesters.4 When one is considering prophylactic regimens for pregnant women, it is important to recognize that the majority of cases of thromboembolic disease occur before delivery, which strongly suggests that prophylaxis should be administered throughout the pregnancy and not just after delivery, as Weinmann and Salzman recommend.
Diagnostic and treatment regimens for thromboembolic events in nonpregnant patients have been well established, as the authors show. Unfortunately, as with many other common medical disorders, treatment regimens and efficacy and outcome data for pregnant women are lacking.
4 ReferencesMarc R. Toglia, M.D.
Valerie M. Parisi, M.D., M.P.H.
Stony Brook Health Sciences Center, Stony Brook, NY 11794-80911
Weinmann EE ,Salzman EW . Deep-vein thrombosis. N Engl J Med 1994;331:1630-1641
Full Text | Web of Science | Medline2
Rutherford S ,Montoro M ,McGehee W ,Strong T . Thromboembolic disease associated with pregnancy: an 11-year review. Am J Obstet Gynecol 1991;164:286-286 abstract.3
Bergqvist D ,Hedner U . Pregnancy and venous thrombo-embolism. Acta Obstet Gynecol Scand 1983;62:449-453
CrossRef | Web of Science | Medline4
Ginsberg JS ,Brill-Edwards P ,Burrows RF , et al. Venous thrombosis during pregnancy: leg and trimester of presentation. Thromb Haemost 1992;67:519-520
Web of Science | Medline
To the Editor:
In their excellent review of deep venous thrombosis, Weinmann and Salzman refer to the “clinical lore” regarding treatment of this condition. A mundane yet important aspect of treatment not addressed in the article, though certainly subject to clinical dogma and lore, is the determination of an appropriate level of activity at the time of the diagnosis. An undetermined period of bed rest, from 24 to 72 hours, seems to be the preference of my colleagues, as well as instructors during my clinical training. The theory is that ambulation increases the risk of embolism. This view is supported by anecdotal reports of pulmonary embolism in patients allowed to walk, though not, to my understanding, by objective assessment.
I have never seen a referenced recommendation regarding the appropriate level of activity, which is an issue we all face each time we care for a patient with deep venous thrombosis. The recommended level of activity does have practical implications if one is considering treatment in an outpatient setting using subcutaneous low-molecular-weight heparin.
John L. Udell, M.D.
Gundersen Clinic, La Crosse, WI 54601To the Editor:
We wonder why Weinmann and Salzman do not mention external compressive therapy as part of the treatment for deep-vein thrombosis. As a consequence of thrombosis, the majority of patients have a post-thrombotic syndrome (chronic venous insufficiency) with edema, eczema, and venous ulceration, involving considerable morbidity and high costs for the health care system.1 It is therefore very important to try to prevent the development of this syndrome, and external compression may be an effective therapy to do so. It has been shown that compression therapy reduces venous volume in the leg2 and increases venous flow velocity.3 On the other hand, neither improvement in the venous muscle pump function nor reduction in venous reflux has been demonstrated. We recommend external compression from the first day that a patient with deep-vein thrombosis is ambulatory.
3 ReferencesVigfús Sigurdsson, M.D.
Abraham H. Preesman, M.D., Ph.D.
Willem A. van Vloten, M.D., Ph.D.
University Hospital Utrecht, NL-3508 GA Utrecht, the Netherlands1
O'Donnell TF Jr ,Browse NL ,Burnand KG ,Thomas ML . The socioeconomic effects of an iliofemoral venous thrombosis. J Surg Res 1977;22:483-488
CrossRef | Web of Science | Medline2
Christopoulos D ,Nicolaides A ,Belcaro G ,Duffy P . The effect of elastic compression on calf muscle pump function. Phlebologie 1990;5:13-193
Lawrence D ,Kakkar VV . Graduated, static, external compression of the lower limb: a physiological assessment. Br J Surg 1980;67:119-121
CrossRef | Web of Science | Medline
To the Editor:
Weinmann and Salzman state, “Anticoagulation should be the first-line treatment for patients with distal deep-vein thrombosis.” Although this assertion is unreferenced, we believe it is based on a study by Lagerstedt et al.1 involving 51 patients with venogram-positive distal thromboses. The investigators reported a dramatic difference in the rate of recurrences after three months: 0 percent in the group that received anticoagulation therapy, as compared with 29 percent in the group that did not receive such therapy. Given the poor sensitivity of noninvasive tests for distal thrombosis, noted in the review, should we be performing venography in all suspected cases to prevent this high incidence of recurrent thrombosis?
How do the authors reconcile the data reported by Lagerstedt et al. with data from more recent studies using serial noninvasive testing for deep-vein thrombosis? These studies, involving large numbers of patients, have had excellent results, in terms of subsequent pulmonary emboli as well as recurrent deep-vein thromboses, among patients with negative serial noninvasive examinations.2-4 These data tend to undercut the 29 percent recurrence rate reported by Lagerstedt et al., raising the question of whether anticoagulation therapy is required in all patients with symptomatic distal deep-vein thrombosis.
4 ReferencesGeoffrey A. Modest, M.D.
Julie Kaufmann, M.D., Ph.D.
Boston City Hospital, Boston, MA 021181
Lagerstedt CI ,Olsson C-G ,Fagher BO ,Oqvist BW ,Albrechtsson U . Need for long-term anticoagulant treatment in symptomatic calf-vein thrombosis. Lancet 1985;2:515-518
CrossRef | Web of Science | Medline2
Heijboer H ,Buller HR ,Lensing AWA ,Turpie AGG ,Colly LP ,ten Cate JW . A comparison of real-time compression ultrasonography with impedance plethysmography for the diagnosis of deep-vein thrombosis in symptomatic outpatients. N Engl J Med 1993;329:1365-1369
Full Text | Web of Science | Medline3
Moser KM. Pulmonary thromboembolism. In: Isselbacher KJ, Martin JB, Braunwald E, Fauci AS, Wilson JD, Kasper DL, eds. Harrison's principles of internal medicine. 13th ed. New York: McGraw-Hill, 1994:1214-20.
4
Huisman MV ,Buller HR ,ten Cate JW ,Vreeken J . Serial impedance plethysmography for suspected deep venous thrombosis in outpatients: the Amsterdam General Practitioner Study. N Engl J Med 1986;314:823-828
Full Text | Web of Science | Medline
Author/Editor Response
The authors reply:
To the Editor: When we reviewed the subject of deep venous thrombosis in the Journal 20 years ago,1,2 the relative merits of many treatment policies, not to mention matters of fact, were in dispute. Some of them still are. Today's physician, schooled in experimental design and able to reject all data except those that are unequivocal, may still be left with only clinical impressions, imperfect recollections, and personal reminiscences.
We do not agree with Toglia and Parisi that thromboembolism associated with pregnancy is primarily a disease in pregnant women, rather than in women in the postpartum state, as is usually believed. The evidence for their view is chiefly from the description by Rutherford et al.3 of the distribution, with regard to delivery, of 93 objectively diagnosed cases of venous thromboembolism among nearly 170,000 pregnancies. A considerably larger fraction of cases occurred before delivery than one would have expected. Unfortunately, Rutherford et al. do not provide us with a denominator indicating the size of the population they studied or the outcomes. Their data are published only in the form of an abstract. There is no sign of the more rigorous analysis that would be required to rule out serious bias in case selection or discernment of the gravity of complications. Since the report by Rutherford et al. is ambiguous, its implications for Toglia and Parisi's hypothesis are unclear.
Sigurdsson et al. provide no data on the use of external compression in the treatment of patients with acute deep-vein thrombosis, but this does not prevent them from advocating graduated limb compression as part of the treatment. They are convinced that they have a good idea, and they want to share it with us despite the absence of data. Maybe external compression would help. Who knows?
The use of phlebography to confirm a suspected diagnosis of calf-vein thrombosis, the use of anticoagulant agents to treat acute thrombosis confined to the calf, and the calculation of cost effectiveness to justify the selection of a course of action — all these controversial practices have their advocates. Effective noninvasive alternatives also exist; we await the results of comparative trials.
Meanwhile, we thank the correspondents for their kind reception of our review. We regret that because of the Journal's characteristic brevity, we are unable to engage in the depth of discussion that these interesting queries deserve.
3 ReferencesEran E. Weinmann, M.D.
Edwin W. Salzman, M.D.
Beth Israel Hospital, Boston, MA 022151
Clagett GP ,Salzman EW . Prevention of venous thromboembolism in surgical patients. N Engl J Med 1974;290:93-96
Full Text | Web of Science | Medline2
Adar R ,Salzman EW . Treatment of thrombosis of veins of the lower extremities. N Engl J Med 1975;292:348-350
Full Text | Web of Science | Medline3
Rutherford S ,Montoro M ,McGehee W ,Strong T . Thromboembolic disease associated with pregnancy: an 11-year review. Am J Obstet Gynecol 1991;164:286-286 abstract.
- Citing Articles (2)
Citing Articles
1
Beatrice K. Launius, B Diane Graham. (1998) Understanding and Preventing Deep Vein Thrombosis and Pulmonary Embolism. AACN Clinical Issues: Advanced Practice in Acute and Critical Care 9:1, 91-99
CrossRef2
LISA DIETHELM, HAIBO XU. (1996) Diagnostic Imaging of the Lung During Pregnancy. Clinical Obstetrics and Gynecology 39:1, 36-55
CrossRef
