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Three Part Question

In [patients with an above knee uncomplicated DVT] is [outpatient management with low molecular weight heparin or traditional inpatient management] feasible [and safer]?

Clinical Scenario

A 25 year old man presents at the Emergency Department with a 2 day history of a swollen and painful right leg. A DVT is suspected and an ultrasound confirms the presence of an extensive clot in the femoral vein. Otherwise he is fit and well. There are no beds in the hospital and you wonder whether the evidence exists to confirm that this patient can be treated safely as an outpatient using low molecular weight heparin.

Search Strategy

Medline 1966-07/00 using the OVID interface.
(Exp venous thrombosis OR "deep vein thrombosis".mp) OR (exp venous thrombosis OR "dvt".mp) OR [(exp thrombosis OR exp venous thrombosis OR "thrombosis".mp) AND (exp veins OR Veins$.mp OR veins$.mp)] AND [(exp hospitilization OR "hospitalisation".mp) OR ("inpatient".mp) OR ("outpatient".mp) OR (exp ambulatory care OR "ambulatory care".mp)] AND [(exp heparin OR exp heparin, low molecular weight OR "heparin".mp) OR (exp anticoagulants OR "anticoagulants".mp) NOT ("prophylaxis".mp) NOT (exp primary prevention OR "prevention".mp)] AND exp therapeutics OR "treatment".mp). Limit to human AND English language

Search Outcome

493 papers identified of which 485 were irrelevant or of insufficient quality for inclusion. The remaining 8 papers are shown in the table.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Lindmarker P and Holmstrom M, 1996, Sweden	434 patients withsymptomatic DVT, 239 proximal,195 distal. Patients were followed up for 3 months.	Cohort	Recurrent DVT, incidence of pulmonary embolus, bleeding events,Death.	Frequency of major events during the administration of LMWH was 0.92% with an exact 95% CI of 0.25-2.35%. During the 3 month follow up period there were 3 re-occurrences and 1 PE.There were no deaths during initial treatment with LMWH.	High incidence of distal DVT (45%) may have affected the complication rate.
Mattiasson I et al, 1997, Sweden	523 consecutive patients from 6 hospitals. Patients were followed up for 3 months.	Cohort	Any bleeding event, Pulmonary embolus (PE),Progression of thrombus	No serious bleeding event was reported.No serious thromboembolic complication was noted.	Excluded patients with thrombus involving the v. iliaca and v.cava, this may reflect the zero incidence of PE
			Eligibility
Grau E et al, 1998, Spain	71 consecutivepatients presenting to the ED with a DVT ( 56 proximal, 15 calf). Patients were assessed monthly for 6 months	Cohort	Recurrent venous thrombo-Embolic event (VTE) Ambulatory care	No patients had VTE recurrence during the 6 months of follow up. Ambulatory care was feasible in 39 (55%) of patients. 24 of these were not hospitalised at all and the remaining 15 were discharged within 2 days.	Small number of patients
Groce JB 3rd, 1998, USA	125/142 patients with acute proximal DVT	Cohort	Length of stay	From 5.4 to 0.97 days.84 patients were in hospital <=24 hours. The remaining 41 stayed between 1.1 and 3 days.	Preliminary results
			Recurrent DVT	1/125
			Bleeding	In 2/125
Harrison L et al, 1998, Canada	89/113 consecutive patients. 69 had proximal DVT, 11 calf vein DVT, 7 had upper extremity DVT, 2 had PE. Patients were followed up at 3 months after initial diagnosis	Cohort	Bleeding episode	There was 1 bleeding episode requiring admission.	Some patients were followed up at 3 months over the telephone which may affectvalidity of findings Possibility that satisfaction questionnaire not validated
			Recurrent VTE	5 cases of recurrent VTE were reported (all had malignant disease)1 death was reported.
			Patient satisfaction	75/82 (91%) were pleased at home treatment
Ting SB et al, 1998, Australia	100 consecutive patients with acute lower limb DVT (53 proximal, distal 47). Patients were followed up for 6 months.	Cohort	Bleeding	6 minor bleeding complications. In 2 of these Dalteparin was stopped.
			Recurrent VTE	4 patients had re – occurrence between 5-12 months.
			PE	No episodes of symptomatic PE reported.
Wells PS et al, 1998, USA	194/233 patients presenting with DVT were recruited into 2 care models. Patients were followed up for 6 months.	Cohort	Recurrent VTE	The overall recurrent event rate was 3.6% (95%CI,1.5%-7.4%).	As patients were cared for in a highly supervised research setting, evidence of their satisfaction/anxiety with the service could have been assessed
			Bleeding events	The overall rate of major haemorrahge was 2.0% (95% CI, 0.6%-5.2%).More than 184/194 patients were treated mainly at home.
Yusen RD et al, 1999, USA	195 hospitalised patients diagnosed as having a proximal DVT were assessed for outpatient treatment.	Cohort	Recurrent VTE,Major bleeding,Death	No complications were recorded in any of the 36 eligible or possibly eligible patients.	Criteria applied retrospectively Lack of documentation may have limited the ability to determine accurate complication rates
			Eligibility	Of the 159 patients classified as ineligible, 13 (8%;95% confidence interval [CI],4 to 12%) died or developed serious complications.

Comment(s)

There are no randomised control trials to answer the question posed. However all the cohort studies come to the same conclusion.

Clinical Bottom Line

Selected patients with uncomplicated proximal DVT can be treated safely as outpatients.

References

1. Lindmarker P, Holmstrom M. Use of low molecular weight heparin (dalteparin), once daily for the treatment of deep vein thrombosis. A feasibility and health economic study in an outpatient setting. Journal of Internal Medicine 1996;240(6):395-401.
2. Mattiasson I, Berntorp E, Bornhov S, et al. Out-patient treatment of acute deep vein thrombosis. Int Angiol 1998;17(3):146-50.
3. Grau E, Real E, Pastor E, et al. Home treatment of deep vein thrombosis: a two years experience of a single institution. Haematologica 1998;83(5):438-441.
4. Groce JB 3rd. Patient outcomes and cost analysis associated with an outpatient deep venous thrombosis treatment program. Pharmacotherapy 1998;18(6Pt3):175S-180S.
5. Harrison L, McGinnis J, Crowther M et al. Assessment of outpatient treatment of deep-vein thrombosis with low-molecular-weight heparin. Arch of Intern Med 1998;158(18):2001-2003.
6. Ting SB, Ziegenbein RW, Gan TE, et al. Dalteparin for deep vein thrombosis: a hospital-in-the-home program. Med J Aust 1998;168(6):272-276.
7. Wells PS, Kovacs MJ, Bormanis J, et al. Expanding eligibility for outpatient treatment of deep vein thrombosis and pulmonary embolism with low-molecular-weight heparin: a comparison of patient self-injection with homecare injection. Arch of Intern Med 1998;158(16):1809-1812
8. Yusen RD, Haraden BM, Gage BF, et al. Criteria for outpatient management of proximal lower extremity deep venous thrombosis. Chest 1999;115(4):972-979.