Table of Contents  
Year : 2019  |  Volume : 6  |  Issue : 4  |  Page : 262-265

Profile of deep-vein thrombosis patients in service hospital with specific reference to high-altitude thrombosis

1 Department of Vascular Surgery, Army Hospital (Research and Referral) Delhi Cantt, New Delhi, India
2 Department of Surgery, Air Force Hospital, Jodhpur, Rajasthan, India
3 Department of Surgery, Military Hospital Namkum, Ranchi, Jharkhand, India
4 Department of Reconstructive Surgery, Army Hospital (Research and Referral) Delhi Cantt, New Delhi, India
5 Medical Branch, Jalandhar, Punjab, India
6 Department of Vascular Surgery, Sir Ganga Ram Hospital, New Delhi, India

Date of Submission14-Jul-2019
Date of Decision13-Sep-2019
Date of Acceptance13-Oct-2019
Date of Web Publication20-Dec-2019

Correspondence Address:
Dr. Atul Kotwal
Medical Branch, Jalandhar, Punjab
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ijves.ijves_41_19

Rights and Permissions

Background: Deep vein thrombosis (DVT) often goes unrecognized and can cause severe morbidity and even mortality. Exposure to high altitude, immobilization, trauma and surgery are commonly recognised risk factors. Thrombophilia is also one of the important risk factors for recurrent thromboembolic events in younger population. Material and Methods: A prospective case series conducted at a zonal service hospital, in the chain of rearward evacuation from high altitude area in north India, among all the patients diagnosed with DVT (N=144) during the study period from Jan 2014 to Dec 2016. After history and clinical examination, the patients proven to have DVT with Colour Doppler Flow Imaging (CDFI) were included in the study. All the patients were treated with low molecular weight heparin (LMWH) initially and overlapped with oral anti-coagulants (OAC). Results: DVT accounted 0.41 % of total hospital admissions. Exposure to high altitude was recognised as the commonest predisposing factor in 25.7% cases. Immobilization, trauma, and surgery were the other common causes identified. Lower extremities, especially left lower limb was found to be most commonly affected in 57.6% cases. Involvement of multiple anatomical venous segments was commonly observed. The incidence of pulmonary embolism was 0.69%. LMWH followed by OAC proved to be an effective treatment modality with 81.2% patients showing improvement,4.9% remaining static and only 13.9% showing worsening.Conclusion: Acute DVT is responsible for the substantial burden of venous thrombo embolism (VTE) in healthy personnel posted to high altitude (HA). Exposure to high altitude, immobilization, trauma and surgery are common predisposing factors of DVT.

Keywords: Deep-vein thrombosis, high-altitude thrombosis, thrombophilia

How to cite this article:
Agrawal V, Anand V, Lal A, Choudhury A, Chatterjee P, Kotwal A, Reddy T S, Bedi V. Profile of deep-vein thrombosis patients in service hospital with specific reference to high-altitude thrombosis. Indian J Vasc Endovasc Surg 2019;6:262-5

How to cite this URL:
Agrawal V, Anand V, Lal A, Choudhury A, Chatterjee P, Kotwal A, Reddy T S, Bedi V. Profile of deep-vein thrombosis patients in service hospital with specific reference to high-altitude thrombosis. Indian J Vasc Endovasc Surg [serial online] 2019 [cited 2023 Jan 30];6:262-5. Available from:

  Introduction Top

Deep-vein thrombosis (DVT) is a common condition that often goes unrecognized and may cause unexplained morbidity and even mortality. It may lead to sudden death due to pulmonary embolism (PE) or long-term morbidity due to postthrombotic syndrome (PTS).[1] In majority of patients with identified predisposing factors, it can be prevented by appropriate prophylaxis. Risk factors for DVT are not exhaustive and include old age, immobilization, surgery, hemophilia, pregnancy, estrogen use, and carcinoma.[2] Exposure to high-altitude (HA) climate is a recognized predisposing factor for the development of DVT, and the risk increases with the duration of exposure. In addition, spontaneous vascular thrombosis may occur both in recreational climber and personnel of the armed forces who get deployed in HA areas.[3] Individuals who remain to stay in HA for longer duration tend to develop a late hypercoagulability state, which peaks at 5 months and persists for as long as the individual stays at HA.[4] The cardinal principle for the prevention of HA thrombosis is to avoid a quick ascent.[3] It is important to avoid dehydration, immobility, cold, and constrictive clothing during ascent to HA. There is no specific prophylactic strategy, although some authors advocate prophylactic antiplatelet agents, acetazolamide, or homocysteine-lowering vitamins.[5],[6] In the Indian population, after a major orthopedic trauma, the incidence of venous thromboembolism among patients receiving thromboprophylaxis was significantly less (8%) as compared to (14.49%) patients not receiving any form of prophylaxis.[7] Thrombophilia, either hereditary or acquired, is one of the important recognized risk factors for DVT and responsible for recurrent DVT in younger patients without any apparent cause.[8] This case series attempts to document the clinical profile and predisposing factors for DVT among personnel of the armed forces in a zonal hospital in HA area.

  Materials and Methods Top

The present study was conducted among DVT patients in a zonal service hospital in the chain of rearward evacuation from HA area (2700-m above the sea level) in North India. This was a prospective case series study among all the patients diagnosed with DVT (n = 144) during the study period from January 2014 to December 2016 in the study hospital. The study participants included both the patients evacuated from the HA areas as well as the patients in the vicinity of the hospital. After obtaining relevant clinical history, clinical examination was performed and color Doppler flow imaging (CDFI) was done to confirm the diagnosis. The criteria for the diagnosis of DVT included occurrence of one of the following parameters in CDFI: absence of phasic (with respiration) pattern of venous blood flow, lack of compressibility, reduced spontaneous/augmented flow, and visible thrombus.[9] All the confirmed patients were treated with low-molecular-weight heparin (LMWH) and overlapped with oral anticoagulants (OAC) till international normalized ratio reached 2–3. They were also given Class II compression stockings and advised limb elevation and rest. Anticoagulation was continued for at least 6 months. The patients were further advised to wear Class II compression stocking lifelong. Patients requiring catheter-directed thrombolysis (CDT) or stenting were further transferred to a vascular center at a tertiary care hospital. Patients were sent on sick leave for 4–6 weeks following which they were re-evaluated. After which, the patients were employed in non-HA area and were advised to follow-up in the nearby hospital. Follow-up data were collected from the surgeon, or directly from the patients telephonically, at 6–12 months. Pain and swelling grossly reduced, with considering >50% recanalization as significant improvement and 20%–30% recanalization as mild improvement for the study purpose. Informed written consent was obtained from all the patients before including them in the study. Institute's ethical committee clearance was sought and obtained before the study was begun. Descriptive statistics was presented in the form of means and proportions for continuous and categorical variables, respectively.

  Results Top

A total of 144 patients of DVT were hospitalized during the study period. The age of the patients varied from 18 to 57 years, with a mean of 26.2 ± 10.5 (standard deviation [SD]) years. Most of the cases (38.3%) were between 19 and 29 years of age. Only 14 cases (11.7%) were above 45 years of age. Majority (95.8%) of the cases were males. Left lower limb involvement was observed in 83 cases (57.6%), whereas 42 cases (29.1%) had right lower limb involvement and 8 cases (5.5%) had bilateral lower limb involvement. Eleven cases (7.6%) had the involvement of upper limb and neck veins [Table 1].
Table 1: Limb involvement

Click here to view

Exposure to HA for >6 months was the most common identifiable predisposing factor (25.7%). Twenty cases (13.9%) had DVT after trauma; 13 cases (9.03%) had undergone prior major operation; three cases (2.1%) had malignancy; two cases (1.3%) had prolonged immobilization due to paraplegia; and 8 cases (5.6%) had other risk factors such as ulcerative colitis, excessive exercise, and ischemic heart diseases. However, 59 cases (40.1%) remained idiopathic, even after detailed evaluation [Table 2].
Table 2: Risk factors for deep-venous thrombosis

Click here to view

All the patients presented with swelling and pain of the affected part. Majority had pain preceding swelling by 2–3 days (94%). Only 4% had the onset of pain and swelling simultaneously and 2% noticed swelling before pain. On examination, the patients exhibited swelling, tenderness, and fever. A total of 74 cases (51.4%) had swelling and tenderness, 39 (27.1%) cases had swelling and fever, whereas 29 (20.1%) cases had all the three features. The difference in the circumference of two limbs varied from 2 to 8 cm. Majority of them, 86 cases (59.7%), had difference of circumference of the limbs of 4–7 cm. Fifty-two cases (36.1%) had difference of 3 cm; three cases (2.1%) had 2 cm, while three cases (2.1%) had 8-cm difference of the circumference of the limbs. The involvement of the venous segments in the patients of the study group is listed in [Table 3]. Involvement of multiple segments was commonly seen in 121 cases (84.03%). Involvement of a single segment of the vein was seen in only 23 patients (15.9%).
Table 3: Vein segment involved

Click here to view

Two patients having impending venous gangrene were transferred to a higher center where they underwent CDT with fairly good result. One patient had PE, confirmed by computed tomography pulmonary angiography. As the symptoms were mild, this patient was treated conservatively with anticoagulation only. Only four patients (2.8%) had minor petechial hemorrhages, which were controlled with adjustment of OAC. Novel OACs were not used for any patients. At 6 to 12-month follow-up, 12 patients (8.3%) became asymptomatic, 62 patients (43.1%) showed significant improvement, 41 patients (28.5%) showed mild improvement, 7 patients (4.9%) remained static, 20 patients (13.9%) had worsening of symptoms (swelling of leg), and one patient (0.69%) of Stage IV gall bladder carcinoma died few days after the onset of DVT.

  Discussion Top

Personnel of the armed forces who are deployed into HA places are usually healthy with no documented morbidity before being inducted. In such places, they are more prone to develop DVT. They usually present with nonspecific pain and swelling of the lower limbs. A provisional diagnosis of DVT is often made on clinical suspicion. It is, therefore, essential to sensitize the environment that pain or swelling of the lower limbs should be considered seriously keeping in mind of DVT, investigated by color Doppler, and treated promptly. However, accurate diagnosis of DVT based on clinical presentation is difficult at times. CDFI has higher accuracy, is of low cost, has portability, and lacks any radiation.[10] Patients were defined as a case of DVT based on CDFI findings in our study.

The incidence of DVT in the general population varies from 2 to 3/10,000 persons/year at the ages of 30–49 to 20/10,000 persons/year at the ages of 70–79.[11] In the present study, age of the patients varied from 18 to 57 years, with a mean of 26.2 ± 10.5 (SD) years. This is in contrast to a review of various studies, which indicates that increasing age is a predictive factor for DVT.[12] This difference in the age of presentation may be due to the fact that our study population was mainly young personnel serving at HA areas. In addition, the study predominantly had male patients (95.8%) due to the fact that our dependent population is largely of male-serving personnel. In general, in civilian population, thrombosis is more common in females, possibly due to the use of oral contraceptive pills and obesity.[13]

Lower limb involvement was noted in 92.4% of our patients; 7.6% of patients had upper limb and neck vein involvement. In the lower extremities, left lower limb alone was involved in 57.6% of cases. This could be possibly because the right iliac artery crosses over the left iliac vein, causing pressure and potential stasis in the left iliac veins and sometimes, it may cause May–Thurner syndrome. It is now well established that endothelial fibrinolytic activity is less in lower extremities, leading to the more common occurrence of DVT in the lower limbs. Upper extremity DVT mostly occurs in young men aged <45 years, particularly during body-building exercises, and accounts for 4%–10% of all DVT cases. Long-term central venous catheters are also associated with upper limb DVT with an incidence of 0.3%–28.3%.[14]

An Indian study documented that HA is an important predisposing factor for thrombosis of deep veins and arteries. Prophylactic antiplatelet agents, acetazolamide, or homocysteine-lowering vitamins are recommended in HA climbers.[6] In an Indian study conducted among 1692 armed forces personnel aged <45 years posted at HA areas for >6 months found that 46% of the personnel had thrombosis-related disease, and long-term stay at HA in associated with thirty times higher risk of spontaneous DVT/PE.[15] In our study, 25.7% cases of DVT were exposed to HA areas (above 10,000 ft altitude) for >6 months' duration. Immobilization, chemotherapy, and central venous line increase the risk of thrombosis.[16] The incidence of postoperative DVT in patients with malignancies is twice that of seen with other surgical patients. A higher proportion of DVT patients had trauma as the predisposing factor in the present study, which is an important occupation hazard in the context of the present study population.

LMWH is more effective than unfractionated heparin in the treatment of DVT with better safety profile. LMWH is also an effective alternative to warfarin for long-term treatment.[17] CDT decreases recurrent thrombosis and PTS, and therefore helps in improving the quality of life.[18] CDT and stenting was not done at our center, and hence we transferred the cases to a higher center for the same. More than one-third of the patients with DVT tend to develop PTS, and 5%–10% of patients develop severe PTS, which may manifest as venous ulceration.[19] Sufficient follow-up was not available in the present study to assess PTS. At short-term follow-up (12 months), 17 patients (11.8%) reported worsening of their symptoms.

One of the shortcomings of our project is that thrombophilia evaluation was not done at our hospital for which we referred all patients at a higher center after 6 months of anticoagulation. The study population being relatively younger and predominantly male, the findings of the present study should be interpreted and compared with those of the general population exercising caution.

  Conclusion Top

Exposure to HA is the most common predisposing factor for DVT in healthy defense personnel, apart from immobilization, trauma, and surgery. DVT involving lower extremities is encountered frequently than DVT involving upper extremities. Multiple anatomical venous segments were involved in majority of the cases. Treatment with LMWH overlapping with OACs and Class II compression stockings along with rest and limb elevation proved to be an effective treatment modality in DVT.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Cohen AT, Agnelli G, Anderson FA, Arcelus JI, Bergqvist D, Brecht JG, et al. Venous thromboembolism (VTE) in Europe. The number of VTE events and associated morbidity and mortality. Thromb Haemost 2007;98:756-64.  Back to cited text no. 1
Deep Venous Thrombosis (DVT) Risk Factors. Treasure Island (FL): StatPearls Publishing; 2019. Available from: [Last accessed on 2019 May 09].  Back to cited text no. 2
Gambhir R, Anand V, Khatana SS, Bedi V. A brief review of high altitude thrombosis. Indian J Vasc Endovasc Surg 2014;1:20.  Back to cited text no. 3
  [Full text]  
Kumar S. High altitude induced deep venous thrombosis: A study of 28 cases. Indian J Surg 2006;68:84-8.  Back to cited text no. 4
Kotwal J, Chopra G, Kotwal A, Sharma Y, Bhardwaj J. High altitude: A hyper coagulable state: Results of a prospective cohort study. Am Soc Hematol 2004;23:4040.  Back to cited text no. 5
Wright A, Brearey S, Imray C. High hopes at high altitudes: Pharmacotherapy for acute mountain sickness and high-altitude cerebral and pulmonary oedema. Expert Opin Pharmacother 2008;9:119-27.  Back to cited text no. 6
Sen RK, Tripathy SK, Singh AK. Is routine thromboprophylaxis justified among Indian patients sustaining major orthopedic trauma? A systematic review. Indian J Orthop 2011;45:197-207.  Back to cited text no. 7
[PUBMED]  [Full text]  
Kreidy R, Irani-Hakime N. Is thrombophilia a major risk factor for deep vein thrombosis of the lower extremities among Lebanese patients? Vasc Health Risk Manag 2009;5:627-33.  Back to cited text no. 8
Naz R, Naz S, Mehboob M, Achakzai A, Khalid GH. Diagnostic yield of color Doppler ultrasonography in deep vein thrombosis. J Coll Physicians Surg Pak 2005;15:276-9.  Back to cited text no. 9
Katz DS, Hon M. Current DVT imaging. Tech Vasc Interv Radiol 2004;7:55-62.  Back to cited text no. 10
Fowkes FJ, Price JF, Fowkes FG. Incidence of diagnosed deep vein thrombosis in the general population: Systematic review. Eur J Vasc Endovasc Surg 2003;25:1-5.  Back to cited text no. 11
Heit JA. Venous thromboembolism: Disease burden, outcomes and risk factors. J Thromb Haemost 2005;3:1611-7.  Back to cited text no. 12
Vandenbroucke JP, Rosing J, Bloemenkamp KW, Middeldorp S, Helmerhorst FM, Bouma BN, et al. Oral contraceptives and the risk of venous thrombosis. N Engl J Med 2001;344:1527-35.  Back to cited text no. 13
Verso M, Agnelli G. Venous thromboembolism associated with long-term use of central venous catheters in cancer patients. J Clin Oncol 2003;21:3665-75.  Back to cited text no. 14
Anand AC, Jha SK, Saha A, Sharma V, Adya CM. Thrombosis as a complication of extended stay at high altitude. Natl Med J India 2001;14:197-201.  Back to cited text no. 15
Prandoni P, Falanga A, Piccioli A. Cancer and venous thromboembolism. Lancet Oncol 2005;6:401-10.  Back to cited text no. 16
Kakkar VV, Gebska M, Kadziola Z, Saba N, Carrasco P, Bemiparin Investigators. Low-molecular-weight heparin in the acute and long-term treatment of deep vein thrombosis. Thromb Haemost 2003;89:674-80.  Back to cited text no. 17
Baldwin ZK, Comerota AJ, Schwartz LB. Catheter-directed thrombolysis for deep venous thrombosis. Vasc Endovascular Surg 2004;38:1-9.  Back to cited text no. 18
Kahn SR. How I treat postthrombotic syndrome. Blood 2009;114:4624-31.  Back to cited text no. 19


  [Table 1], [Table 2], [Table 3]


Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  In this article
   Materials and Me...
   Article Tables

 Article Access Statistics
    PDF Downloaded124    
    Comments [Add]    

Recommend this journal