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Deep venous thrombosis after major abdominal surgery in a Ugandan hospital: a prospective study

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Deep venous thrombosis (DVT) is a major cause of morbidity and mortality among postoperative patients. Its incidence has been reported to range between 16% and 38% among general surgery patients and may be as high as 60% among orthopaedic patients. The most important clinical outcome of DVT is pulmonary embolism, which causes about 10% of hospital deaths. In over 90% of patients, occurrence of DVT is silent and presents no symptoms until onset of pulmonary embolism and/or sudden death. The only effective way of guarding against this fatal condition is therefore prevention/prophylaxis. However, prophylaxis programs are usually based on the estimated prevalence of DVT in that particular community. There is currently no data concerning rates of postoperative DVT in Uganda.The purpose of the study was therefore to determine the prevalence of DVT among postoperative patients at Mulago Uganda's National Referral Hospital. A cross sectional descriptive study was conducted between March and June 2011. Eligible patients were identified and screened and patient details were collected. Clinical examinations were done on postoperative days (PODs) 1, 2, and 4 and Doppler ultrasounds were done on POD 7 and POD 21 to assess for DVT. Patients found with DVT were treated appropriately according to local treatment guidelines. A total of 82 patients were recruited, 4/82 (5%) had DVT. The most common risk factor was cancer. The overall mean age was 45 years (range 20--83 years). The male to female ratio was 1.6:1. Participants with more than one risk factor for DVT were 16/82 (20%). Prevalence of DVT among major post-abdominal surgery patients was low (5%). Cancer was the most common associated factor apart from surgery.
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... Prevalence of DVT in patients after surgery Three studies reported the prevalence of DVT in patients after surgery [18][19][20]: two from sub-Saharan Africa [18,19], and one from North Africa [20]. Overall, the prevalence of DVT following surgery in Africa varied between 2.4% and 9.6%. ...
... Prevalence of DVT in patients after surgery Three studies reported the prevalence of DVT in patients after surgery [18][19][20]: two from sub-Saharan Africa [18,19], and one from North Africa [20]. Overall, the prevalence of DVT following surgery in Africa varied between 2.4% and 9.6%. ...
... Overall, the prevalence of DVT following surgery in Africa varied between 2.4% and 9.6%. In sub-Saharan Africa, this prevalence was, respectively, 2.4% in the study by Adeleye et al. in Nigeria [19], and 5% in the study by Muleledhu et al. in Uganda [18] ( Table 2). The prevalence of DVT was 9.6% in Sudan [20]. ...
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Essentials Venous thromboembolism (VTE) is among the three main causes of cardiovascular disease worldwide. This review is the first to summarize the epidemiology of VTE in African populations. The prevalence of VTE in Africa is high following surgery, in pregnancy and post-partum. At least one quarter of patients at risk of VTE in Africa are not receiving prophylaxis. Summary: Background Venous thromboembolism (VTE) is among the three leading causes of cardiovascular disease worldwide. Despite its high burden, there has been no previous study summarizing the epidemiology of VTE in African populations. Hence, we conducted this systematic review to determine the prevalence, incidence and mortality associated with VTE, and to evaluate the use of VTE prophylaxis in Africa. Methods We searched PubMed, Scopus and African Journals Online to identify articles published on VTE in Africa from inception to November 19, 2016, without language restriction. The reference list of eligible articles were further scrutinized to identify potential additional studies. Results Overall, we included 21 studies. The great majority of the studies yielded a moderate risk of bias. The prevalence of deep vein thrombosis (DVT) varied between 2.4% and 9.6% in postoperative patients, and between 380 and 448 per 100 000 births per year in pregnant and postpartum women. The prevalence of pulmonary embolism (PE) in medical patients varied between 0.14% and 61.5%, with a mortality rate of PE between 40% and 69.5%. The case-fatality rate after surgery was 60%. Overall, 31.7-75% of the patients were at risk of VTE, and between 34.2% and 96.5% of these received VTE prophylaxis. Conclusion The prevalence of VTE and associated mortality are high following surgery, and in pregnant and postpartum women in Africa. At least one-quarter of patients who are at risk for VTE in Africa are not receiving prophylaxis. These results are generated from studies with small sample size, highlighting an urgent need for well-designed studies with larger sample size to evaluate the true burden of VTE in Africa.
... They found that 5% had DVT postsurgery and cancer was the commonest risk factor. [29] Fall et al. also did a 3 year cross-sectional case-control study of patients admitted to emergency wards on account of DVT or PE, in various hospitals in Dakar, Senegal. [30] Their results showed that cancer was a risk for VTE in 3.81% of the 105 patients evaluated during the study. ...
... Kotila et al. [27] Nigeria Retrospective Review of treatment of DVT and PE 178 22 (12.2) Kingue et al. [28] Cameroun Retrospective Sonological findings of suspected DVT 18 4 (22.2) Muleledhu et al. [29] Uganda Prospective Evaluating incidence of DVT in 82 patients postmajor abdominal surgery 4 4 (100) ...
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The burden of cancer is gradually increasing in developing countries in Africa. This has accounted for significant rates of morbidity and mortality. The development of thrombosis in cancer patients impacts significantly on the outcome of care. Cancer‑associated thrombosis may occur due to the stage of cancer, its organ site, treatment modality among other reasons. Some reports of studies of the management of patients with deep venous thrombosis (DVT) from African centers have identified malignancy as a significant risk factor for DVT. However, there are no reported studies in cancer patient groups to evaluate the prevalence, risk factors, and efficacy of prophylactic measures in Africa. This review focuses on the epidemiology, pathophysiology, risk indicators, and reports of thrombosis affecting cancer patients in Africa. The aim is to increase awareness and draw the attention of clinicians and oncologist in cancer management in Africa to the need for a robust multicenter research, establishing evidence‑based interventions, and guidelines for improved patient outcome.
... Among our patients, 4.5% suffered a DVT event following surgery. This finding is in line with results reported by other publications from Nigeria [30], and Uganda [31], which found that the prevalence of DVT in patients after surgery is 2.4 and 5%, respectively. The present study did not find sex to be a significant risk factor; however, among the female study participants, pregnancy, and the use of oral contraceptive pills increased the risk of developing DVT. ...
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Deep vein thrombosis (DVT) is a critical condition and a potential cause of mortality and morbidity in Africa and worldwide with a high recurrence rate. The study was designed to assess the roles of natural anticoagulants and fibrinolytic regulatory factors in the development of DVT in Sudanese patients. A case-control study was conducted in Omdurman Teaching Hospital, Khartoum State over a period of 1 year. The study enrolled 200 patients diagnosed with DVT and 200 age-matched and gender-matched controls. Demographic data and data on acquired risk factors were collected using a semi-structured questionnaire. Protein C (PC), protein S (PS), antithrombin III (AT-III), thrombin-activable fibrinolysis inhibitor (TAFI), and plasminogen activator inhibitor-1 (PAI-1) were measured in patients and controls. Among the patients with DVT, 5.5% had PC deficiency, 8.5% had PS deficiency, and 3% had AT-III deficiency. Elevated TAFI and PAI-1 levels were demonstrated in 1.5 and 0.5% of patients, respectively. Risk factors for DVT (overweight, surgical history, and family history of DVT) were remarkably higher in patients than in controls. Among the female participants, pregnancy and usage of oral contraceptive pills were the highest associated risk factors for DVT. The findings concluded that the early assessment of risk factors, including the measurements of natural inhibitors, can predict the occurrence of DVT before it is actually detected in patients.
... Deep venous thrombosis (DVT) is a major cause of morbidity and mortality among postoperative patients. Its incidence has been reported to range between 16% and 38% among general surgery patients and may be as high as 60% among orthopedic patients [17] . The most important complication of DVT is PE, which causes about 10% of hospital deaths. ...
Article
The preoperative evaluation of candidates to non-cardiac surgery requires a knowledge of factors related both to the type of surgery and to the risk of each patient, in order to predict the potential cardiovascular complications. Over the past several decades, the field of preoperative cardiac evaluation before non-cardiac surgery has evolved substantially on the basis of the current guidelines of international medical societies. The aim of this paper is to summarize available evidence on the risk of non-cardiac surgery, focusing on appropriate cardiovascular assessment prior to surgery.
... The incidence of VTE differs according to ethnicity, and studies from America showed that African-Americans have above 5-fold greater incidence than Asian-ancestry populations, while Hispanic and European populations have intermediate risk [15]. Generally, the incidence of VTE is 30% to 60% higher in blacks than in whites [16]. ...
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Venous thromboembolism (VTE) is a fatal complication in patients with active cancer. VTE is associated with substantial morbidity and mortality. The risk of VTE is usually precipitated by a combination of factors that includes surgery, trauma, hospitalization, cancer with or without chemotherapy, and also the use of central nervous catheters. A risk assessment model such as the modified Khorana risk score is needed to select ambulatory cancer patients for thromboprophylaxis. This study aims to provide a concise review of the use of the Khorana scoring system in the evaluation of the risk of VTE among cancer patients. A comprehensive literature search was done using search engines linked to academic databases including Google Scholar, Pubmed, Ebsco, Hinari, Scopus, etc. Studies involving venous thromboembolism in cancer patients were thoroughly studied. Only papers with risk of cancer-associated thrombosis and articles on Khorana risk scoring system were used. VTE is associated with increased morbidity and mortality among cancer patients due to the hypercoagulability and prothrombotic state of cancer. There is a paucity of information on the risk assessment of VTE in cancer patients using the Khorana scoring system in our environment. More advocacy of the use of the Khorana scoring system for the assessment of VTE among cancer patients should be encouraged to mitigate the increasing morbidity and mortality associated with cancer patients in Nigeria.
... Im Vergleich haben beispielsweise offene bauchchirurgische Eingriffe ein postoperatives Thromboserisiko von ca. 1,6-5 % [8,9]. ...
Article
Zusammenfassung Sämtliche in der Varizenchirurgie angewandten Verfahren beherbergen Risiken. Die Risiken der klassischen operativen Sanierung der Varikosis mittels Stripping sind in der Literatur sehr ausführlich beschrieben. Bei den neueren therapeutischen Optionen, wie z. B. den endovenösen Therapien oder der Schaumsklerosierung werden die möglichen Komplikationen erst in jüngerer Zeit systematisch ausgewertet. Dementsprechend liegen derzeit im Vergleich wenige Daten hierzu vor. Betrachtet man die Lebensqualität des Patienten in den neuesten Vergleichsstudien und Metaanalysen, zeigt sich, dass perioperativ kaum Unterschiede in der Mobilität, Mortalität und Lebensqualität des Patienten bei den unterschiedlichen Therapieverfahren bestehen [1]. Insgesamt ist davon auszugehen, dass die klassische operative Sanierung der Varikosis mittels Crossektomie, Stripping und Miniphlebektomien im Vergleich zu den endovenösen Therapieverfahren sowohl mit einem erhöhten Blutungsrisiko, also auch mit einem erhöhten postoperativen Infektionsrisiko einhergeht. Grundsätzlich ist das Blutungsrisiko, als auch das Infektionsrisiko jedoch auch bei der Operation als niedrig einzuschätzen. Das perioperative Nervenverletzungsrisiko scheint bei beiden Verfahren ähnlich häufig zu sein, wobei repräsentative Daten aus Vergleichsstudien fehlen. Das postoperative Thromboserisiko mit ggf. konsekutiver Lungenarterienembolie ist unseres Erachtens nach bei den endovenösen Verfahren höher einzustufen als nach einer klassischen operativen Sanierung der Varikosis. Kosmetisch beeinträchtigende, postinflammatorische Hyperpigmentierungen im OP-Gebiet treten häufiger nach endovenösen Therapieverfahren und nach Sklerosierungstherapien auf.
... The incidence of lower limb deep vein thrombosis in post-operative period in general surgery patients varies from 16% and 38%. 2 Hospitalized patients have over 100-fold increased incidence of acute DVT over community residents. 3 The reported incidence has not changed much over past couple of decades. ...
Article
Background: Deep vein thrombosis (DVT) is a common but elusive illness that can result in disability and death if not recognized and treated effectively. The reported incidence has not changed much over past couple of decades. The aim of this study was to identify the risk of deep vein thrombosis related to the number of days of immobility and the role of low molecular weight heparin in the prevention of deep vein thrombosis.Methods: A total of hundred (n=100) patients undergoing laparotomy were studied in the post-operative period between January 2014 and December 2016. Patients were divided into two groups alternatively; Group I patients did not receive any DVT prophylaxis and Group II patients were given low molecular weight heparin once a day till mobilization. From 3rdPOD, all the patients were evaluated with detailed history and lower limb examination. D-dimer study was done in all the patients and if positive then followed by Color Venous Doppler. Regular follow-ups were done weekly once for a month, every two weeks for next month and once a month thereafter, minimum for 6 months.Results: A total of hundred (n=100) patients, including 65 men and 35 women, with median age of 40 years underwent laparotomies in 2 years by a single unit. The incidence of Lower Limb DVT in Group I was 8%. The risk factors associated with DVT were sex, BMI, smoking and Malignancy. The signs and symptoms associated with DVT were swelling of lower limbs, pain and tenderness, fever and Homan’s and Moses signs. The D-dimer test results were positive in 9 patients. Color Venous Doppler identified DVT in 8 patients. On regular follow- ups, remissions of clinical symptoms were recorded and repeat Doppler scans showed recanalization in all the patients after 6 months.Conclusions: Deep Vein Thrombosis is multifactorial, and post-operative patients account for majority of cases. Early mobilization and Prophylactic Low Molecular Heparin prevents DVT in abdominal surgeries.
... In our results, male gender was also a risk factor of postoperative complications. Interestingly, there were studies revealed that male gender was associated with longer duration of surgery [33], higher risk of postoperative deep venous thrombosis [34], and increased mortality [35]. The association between gender and patients' outcome after surgery for pheochromocytoma needs to be further evaluated. ...
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Background Current evidences show that regional anesthesia is associated with decreased risk of complications after major surgery. However, the effects of combined regional-general anesthesia remain controversial. The purpose of our study was to analyze the impact of anesthesia (combined epidural-general anesthesia vs. general anesthesia) on the risk of postoperative complications in patients undergoing open surgery for pheochromocytoma. Methods This was a retrospective cohort study. 146 patients who underwent open surgery for pheochromocytoma (100 received combined epidural-general anesthesia and 46 received general anesthesia) in Peking University First Hospital from January 1, 2002 to December 31, 2015 were enrolled. The primary outcome was the occurrence of postoperative complications during hospital stay after surgery. Multivariate Logistic regression models were used to analyze the association between the choice of anesthetic method and the risk of postoperative complications. Results 17 (11.6%) patients developed complications during postoperative hospital stay. The incidence of postoperative complications was lower in patients with combined epidural-general anesthesia than in those with general anesthesia (6% [6/100] vs. 23.9% [11/46], P = 0.006). Multivariate Logistic regression analysis showed that use of combined epidural-general anesthesia (OR 0.219, 95% CI 0.065–0.741; P = 0.015) was associated with lower risk, whereas male gender (OR 5.213, 95% CI 1.283–21.177; P = 0.021) and perioperative blood transfusion (OR 25.879; 95% CI 3.130–213.961; P = 0.003) were associated with higher risk of postoperative complications. Conclusions For patients undergoing open surgery for pheochromocytoma, use of combined epidural-general anesthesia may decrease the occurrence of postoperative complications.
... Its incidence has been reported to range between 16 and 38% among general surgery patients and may be as high as 60% among orthopedic patients. The most important clinical outcome of DVT is PE, which causes about 10% of the hospital deaths [13]. ...
Article
Venous thromboembolism (VTE) occurs in about 5 percent of patients undergoing major abdominal surgeries. Prophylaxis of VTE is recommended using unfractionated heparin (UF) or low molecular weight heparin (LMWH) in high-risk patients. In spite of advantages and confirmed cost-effectiveness of LMWH, high costs of enoxaparin branded preparations limit its use. We aimed to compare the efficacy and safety of two enoxaparin preparations. In this open-label randomized clinical trial, 200 patients were recruited to recieve PDxane® or Clexane®, 40 mg subcutaneously daily, from the day of surgery for 10 days. The patients were evaluated for VTE occurrence and side effects considering clinical and laboratory examinations at the beginning and day 10. No cases of proximal or distal VTE or life threatening bleeding were observed among 102 and 98 patients who received PDxane® and Clexane®, respectively. The adverse effects observed in PDxane® and Clexane® groups included injection site reactions (rash: P = 0.97; pain: P = 0.55 and erythema: P = 0.33), anemia (P = 0.32), hematuria (P = 0.16), confusion (P = 0.3), and increased liver transaminases (AST ≥ 3 × ULN: P = 0.16 and ALT ≥ 3 × ULN: P = 0.66). In according to the study results PDxane® was of similar efficacy and safety compared to Clexane® in preventing VTE following major obstetric-gynecological surgeries. Considering lower cost of PDxane®, it could be a safe and effective alternate for VTE prophylaxis in the patients undergoing such types of surgeries.
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The incidence of venous thromboembolism has not been well described, and there are no studies of long-term trends in the incidence of venous thromboembolism. To estimate the incidence of deep vein thrombosis and pulmonary embolism and to describe trends in incidence. We performed a retrospective review of the complete medical records from a population-based inception cohort of 2218 patients who resided within Olmsted County, Minnesota, and had an incident deep vein thrombosis or pulmonary embolism during the 25-year period from 1966 through 1990. The overall average age- and sex-adjusted annual incidence of venous thromboembolism was 117 per 100000 (deep vein thrombosis, 48 per 100000; pulmonary embolism, 69 per 100000), with higher age-adjusted rates among males than females (130 vs 110 per 100000, respectively). The incidence of venous thromboembolism rose markedly with increasing age for both sexes, with pulmonary embolism accounting for most of the increase. The incidence of pulmonary embolism was approximately 45% lower during the last 15 years of the study for both sexes and all age strata, while the incidence of deep vein thrombosis remained constant for males across all age strata, decreased for females younger than 55 years, and increased for women older than 60 years. Venous thromboembolism is a major national health problem, especially among the elderly. While the incidence of pulmonary embolism has decreased over time, the incidence of deep vein thrombosis remains unchanged for men and is increasing for older women. These findings emphasize the need for more accurate identification of patients at risk for venous thromboembolism, as well as a safe and effective prophylaxis.
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When ultrasonography is used to investigate deep-vein thrombosis, serial testing is recommended for those who test negative initially. Serial testing is inconvenient for patients and costly. We aimed to assess whether the calculation of pretest probability of deep-vein thrombosis, with a simple clinical model, could be used to improve the management of patients who present with suspected deep-vein thrombosis. Consecutive outpatients with suspected deep-vein thrombosis had their pretest probability calculated with a clinical model. They then underwent compression ultrasound imaging of proximal veins of the legs. Patients at low pretest probability underwent a single ultrasound test. A negative ultrasound excluded the diagnosis of deep-vein thrombosis whereas a positive ultrasound was confirmed by venography. Patients at moderate pretest probability with a positive ultrasound were treated for deep-vein thrombosis whereas patients with an initial negative ultrasound underwent a single follow-up ultrasound 1 week later. Patients at high pretest probability with a positive ultrasound were treated whereas those with negative ultrasound underwent venography. All patients were followed up for 3 months for thromboembolic complications. 95 (16.0%) of all 593 patients had deep-vein thrombosis; 3%, 17%, and 75% of the patients with low, moderate, and high pretest probability, respectively, had deep-vein thrombosis. Ten of 329 patients with low pretest probability had the diagnosis confirmed, nine at initial testing and one at follow-up. 32 of 193 patients with moderate pretest probability had deep-vein thrombosis, three diagnosed by the serial (1 week) test, and two during follow-up. 53 of 71 patients with high pretest probability had deep-vein thrombosis (49 by the initial ultrasound and four by venography). Only three (0.6%) of all 501 (95% CI 0.1-1.8) patients diagnosed as not having deep-vein thrombosis had events during the 3-month follow-up. Overall only 33 (5.6%) of 593 patients required venography and serial testing was limited to 166 (28%) of 593 patients. Management of patients with suspected deep-vein thrombosis based on clinical probability and ultrasound of the proximal deep veins is safe and feasible. Our strategy reduced the need for serial ultrasound testing and reduced the rate of false-negative or false-positive ultrasound studies.