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| ORIGINAL ARTICLE |
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| Year : 2023 | Volume
: 18
| Issue : 3 | Page : 347-352 |
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Assessment of risk factors of deep-vein thrombosis after lower limb surgery
Gajanan Pisulkar, Ankur Salwan, ShaunakBabanrao Taywade, Abhiram Awasthi, Amit Saoji
Department of Orthopedics, Jawharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Sawangi(M), Wardha, Maharashtra, India
| Date of Submission | 06-Aug-2022 |
| Date of Decision | 18-Jan-2023 |
| Date of Acceptance | 02-Feb-2023 |
| Date of Web Publication | 29-Aug-2023 |
Correspondence Address:
Dr. ShaunakBabanrao Taywade
Assistant Professor, Department of Orthopedics, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Sawangi(M), Wardha, Maharashtra
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jdmimsu.jdmimsu_351_22
Background: Deep vein thrombosis is one of the most common condition affecting adults worldwide. The condition is characterized by the presence of blood clots in the veins. The clots commonly develop in the lower limb veins. Deep vein thrombosis is the most common complication after any lower limb surgery and is a prominent complication post-orthopaedic surgery in individuals of any age due to failure of the valves. Aim and Objectives: The aim of our study is to assess the risk factors following lower limb surgery. Methodology: The individuals who fulfill the inclusion criteria were tested using ultrasonography and duplex color Doppler unit examination at 7.5 MHz and 10 MHz using high frequency probes to assess the presence of thrombus in the deep veins of the individuals who have undergone the surgeries. The assessment was recorded on the assessment sheet and analyzed using SPSS statistical software, and the results were drawn. Results: In this study, the individuals were mostly from the age group 59–68 years and a total of 202 patients were included. 136 patients are diagnosed as suffering from DVT following orthopedic surgery. Conclusion: We conclude that the occurrence of DVT after lower limb surgery depends on various factors such as the duration of surgery, the period of immobilization, prior history of DVT and post-operative stay, and various other factors such as age and gender. We found that extramedullary implants have a relative risk of 2.93. Additionally, we also concluded that clinical signs and symptoms are not reliable measures to identify incidence of DVT.
Keywords: Deep-vein thrombosis, Doppler, pulmonary embolism
How to cite this article:
Pisulkar G, Salwan A, Taywade S, Awasthi A, Saoji A. Assessment of risk factors of deep-vein thrombosis after lower limb surgery. J Datta Meghe Inst Med Sci Univ 2023;18:347-52 |
| Introduction | |  |
Clinically, venous thromboembolism appears as pulmonary embolism (PE), deep-vein thrombosis (DVT), or both. It has three major complications: postthrombotic syndrome, fatal PE, and recurring nonfatal venous thromboembolism (VTE). In patients with symptomatic DVT or PE, the probability of recurrent nonfatal thromboembolism is estimated to be 5%−10% in the 1st year following diagnosis and around 2%−3% every year beyond that. Following a DVT, 20%−30% of people develop postthrombotic syndrome, which is characterized by chronic venous insufficiency, discomfort, and limb edema. There are no reliable estimates of the probability of lethal PE; the most feared consequence of PE and DVT.[1] The THRIFT classification, which was modified by the Fifth ACCP consensus statement and has been used to classify the most well-studied venous thromboembolism risk in surgery as low, moderate, or high-risk factors assessment based on the types of surgery.[2],[3] Medical patients have been featured in this category.
Minor surgery (less than 30 minutes): Patients with no co morbidities other than advanced age (> 40age). There are no extra risk factors in a procedure lasting less than 30 minutes.
Moderate surgeries: The moderate surgeries last longer than 30 minutes, and the major risk factors for such patients are age over 40 and the presence of co-morbidities such as heart disease, lung disease, or cancer. Burns or severe trauma patients with a history of deep vein thrombosis, pulmonary embolism, or thrombophilia are more likely to have minor surgery, trauma, or illness.[4],[5]
Group at high risk procedures include fractures and severe orthopaedic surgery on the pelvis, hip, or lower limb. Surgery to remove cancer from the abdomen or pelvic.[6] Individuals suffering from deep vein thrombosis, significant surgery, trauma, or illness.[7] Thrombosis, pulmonary embolism, or thrombophilia are all terms for the same condition. paralysis of the lower limbs (hemiplegia, stroke or paraplegia) and amputation of the entire limb.[8],[9]
Materials and Procedures
After getting the approval from the institutional ethical committee (DMIMS (DU)/IEC/2022/435) the observational study was commenced in the AVBRH hospital. The sample size for the study was calculated using G* Power analysis the sample was 202 individuals and the study was initiated in the month of October 2022 to December 2022.
Inclusion Criteria
Individuals who have undergone any major orthopedic surgeries (THR, TKR, supracondylar femur fracture, midshaft tibia fracture), Individuals above the age of 18.
Exclusion Criteria
Individuals below the age of 18.
Compound Grade III (Gustilo Anderson) fracture of the lower limb.
Preoperative and postoperative patient and procedural characteristics were recorded:
- Age,
- Gender,
- History of smoking,
- History of cancer,
- Previous VTE history,
- VTE in the family,
- Varicose veins
- Obesity (a BMI of 30 or above),
- Whether the patient undergoing hormonal replacement treatment or not,
- Thrombophilia history,
- Tourniquet usage during the operative period.
- The use of regional anaesthesia.
- Surgery lasting more than two hours,
- Postoperative immobility for more than 72 hours.
Analysis statistical
A total of 202 patients were included based on the projected incidence of documented deep-venous thrombosis and sudden death at discharge (primary end goals) and follow-up following surgery. The following quantitative and qualitative data were analyzed: A number of instances, mean, median, standard deviation, and range are all quantitative data. A number of cases, relative risk, and percentage with a 95% confidence interval to identify risk variables, univariate, and multivariate analyses were used. There are relative hazards and their 95% confidence intervals presented.
Analysis of data
The information was classified into four categories: All postsurgery patients' epidemiological data evaluation of risk factors GraphPad Prism 4 software was used to analyze all of the data.
Materials
We screened all of the patients in our research using a noninvasive duplex color Doppler on the sixth post-operative day and an invasive contrast venography technique on the seventh post-operative day.[10],[11] The material used for the treatment are mentioned below
- Ultrasonography & Duplex colour Doppler Unit duplex colour Doppler examination 7.5 MHz and 10 MHz high frequency probes.
- Digital Subtraction Angiography Unit for Invasive Venography Phillips Allura FD 20Contrast - Iohexol 350 mg diluted 50% are required for the assessment.
Methods
Duplex colour Doppler examination was conducted by an expert radiologist utilising 7.5 or 10 MHz linear transducer probes. The operated lower leg was scanned from the calf to the groin area on the sixth post-operative day. The anterior and posterior tibial vessels, popliteal vessels, peroneal vessels, superficial and common femoral veins were all visible. Non-compressibility and the presence of an intra-luminal thrombus were seen as a good indicator of DVT. [Table 1] below showing the reliability of the diagnostic test for diagnosing DVT.
During their hospital stay, an experienced orthopedic surgeon checked the patients twice daily for clinical signs or symptoms of underlying VTE, such as fever, calf edema, pain, or calf soreness. If underlying VTE was suspected, the duplex color Doppler examination was conducted as soon as feasible, regardless of the day of the study.
Invasive contrast venography
Of the 7th postoperative day, ascending contrast venography on the operated lower leg was performed. Previously, venography was conducted when there was a suspicion of clinical DVT or PE. We used the technique outlined by Rabinov and Paulin (1972), as well as the Lensing et al.[12],[13] thrombosis diagnostic criteria (1992).
The venograms were interpreted as being:
- Normal
- Showing thrombosis
- Inadequate or filling defect.
Each venogram series was independently interpreted by two radiologists, and any disagreements were addressed to establish a consensus. Thrombi in the calf were categorized as distal, while those in the popliteal or femoral arteries were classified as proximal. The risk factor assessment for DVT is mentioned in [Table 2] below.
| Results and Observations | | |
Ours is a prospective study performed on 202 Indian patients undergoing major lower limb surgery. The study was carried out in the Department of Orthopedics, J. N. Medical College and AVBRH, DMIMSU Sawangi (Meghe) from October 2022 to December 2022. In this study, the age range of the 202 patients varied from 18 to 99 years. The majority of the patients were in the age of 59 to 68 years, i.e. 25.74%. The mean age of the patients is 51.57 years with standard deviation of 19.27. In our study, although the maximum patients (52) were of age group of 59–68, the maximum number of DVT-positive patients[3] were in the age group of 69–78. Out of 202 patients, 136 (67.3%) are males and 66 (32.6%) are females. Of 12 patients who tested positive for DVT, seven were male and five were female which shows equal sex incidence. When we analyzed our data for the type of fracture, out of 202 patients, the largest group was formed by intertrochanteric fracture, i.e. 85 patients (42.08%) followed by fracture neck femur 37 cases (18.32%), shaft femur 35 cases (17.33%), and fracture tibia 26 cases (12.87%); other diagnoses are THR 7 cases, TKR 2 cases, fracture proximal femur 4 cases, supracondylar femur fracture 4 cases, and miscellaneous 2 cases. Out of 12 cases positive for DVT, 7 (58.33%) showed proximal thrombi and 5 cases (41.67%) showed distal thrombi. Again out of 12 patients, 11 (91.67%) showed ipsilateral DVT, whereas one (8.33%) showed evidence of contralateral DVT is compiled in the following heads as mentioned in the [Figure 1] below.
| Discussion | | |
The age range of the 202 patients in this research ranged from 18 to 99 years. The average age of the patients in our research was 51.5 years. The majority of the patients, or 25.74%, were between the ages of 49 and 68. The incidence of DVT was greatest in the age range of 69–78 years, accounting for 8.10%. It was shown that the prevalence of DVT rose with age. In our analysis, two DVT-positive individuals were between the ages of 18 and 28, which is a quite substantial number. The analysis of risk variables reveals that these two instances were related with a substantial number of risk factors (smoking history, tourniquet usage, surgery lasting more than 2 h, and postoperative immobilization lasting more than 72 h).
Several studies have shown a relationship between increasing age and an increased risk of VTE. Patients over the age of 40 are at much greater risk than younger patients, and the risk almost doubles with each subsequent decade. As a consequence, risk classification based on a simple dichotomy of age above or below 40 years fails to account for the significantly elevated risk among the elderly. VTE is rare in children, and most have severe risk factors, such as repetitive trauma, limb fractures, or indwelling central venous lines.
Out of 202 patients, 136 (67.3%) are men and 66 (32.6%) are girls, with 7 and 5 testing positive for DVT, respectively. Thus, the male population has a DVT incidence of 5.14%, whereas the female population has a DVT incidence of 7.57%. Our findings are consistent with those of Stulberg et al.,[9] who found a higher incidence of DVT in females. However, Stringer et al.[10] found a similar prevalence of DVT in both sexes. According to Silverstein et al.,[10] the incidence of DVT increases with age in females, whereas according to Geerts et al.,[2] the gender of the patients has no effect on the development of DVT.
When we reviewed our data for fracture type, we found that intertrochanteric fracture was the most common, accounting for 85 patients (42.08%), followed by fracture neck femur 37 cases (18.32%), shaft femur 35 cases (17.33%), and fracture tibia 26 instances (12.87%). Other diagnoses include THR in seven instances, TKR in two cases, proximal femur fracture in four cases, supracondylar femur fracture in four cases, and miscellaneous in two cases. When the incidence of DVT was broken down by the type of injury, intertrochanteric fracture had the highest incidence of 8.23%, followed by fracture shaft femur 5.71% and tibial fracture 3.84%. Supracondylar fracture and proximal femoral fracture had the greatest incidence of 25%. There were no DVT cases among THR and TKR patients. This might be explained by the minimal number of instances in this group. Our findings are close to those of Mitra et al.,[12],[14] who found a trochanteric fracture rate of 11.8%. This contradicts Agarwala et al.,[15] who observed venographic indications of DVT in 55%–60% of their TKR patients. Mavalankar et al.[16] discovered that DVT occurred more often after surgery for a femoral neck fracture, and that DVT incidence was lowest in TKR patients (3.4%). Jain et al.[17] discovered no DVT cases in TKR patients. Other Asian studies, including as those of Fujita et al.,[18] Sudo et al.,[19] and Dhillon et al.,[20] found that TKR was associated with the greatest incidence of DVT, followed by THR surgery. Stulberg et al.[9] observed similar results, demonstrating DVT in 84% of patients. Stringer et al.[9] established that TKR has a substantial risk of ipsilateral DVT in 56.4% of cases. Clarke et al.[21] also observed a 66% incidence of DVT following TKR and a 32% prevalence after THR.
Seven (58.33%) of the 12 DVT patients had proximal thrombi, whereas 5 (41.67%) had distal thrombi. Again, 11 (91.67%) of the 12 patients had ipsilateral DVT, whereas 1 (8.33%) had contralateral DVT. The patient with contralateral DVT had a history of DVT and was also clinically diagnosed with PE. Our findings are analogous to those of Jain et al.,[17] who discovered proximal DVT in two individuals (100%) but no distal DVT. Dorfman et al.[22],[23] similarly observed a 78% incidence of proximal DVT. Piovella et al.[23] similarly found a 17.1% proximal DVT rate. These results contradict those of Bagaria et al.,[24] Agarwala et al.,[25] Ciccone et al.,[26] and Davidson et al.,[27] who found a greater incidence of distal DVT than proximal DVT.
In terms of thrombi side, our results are consistent with those of Stulberg et al.,[4] who found a greater incidence of thrombi in the ipsilateral limb compared to the contralateral limb. Davidson et al.[27] found that ipsilateral surgery was a significant predictor of DVT in their sample. They found that screening limbs that have not been operated on for DVT in asymptomatic patients is unnecessary.
Identifying the risk factors for the development of VTE is important because it allows clinicians to identify at-risk people and administer appropriate prophylaxis. Several studies have been undertaken in the west to determine the risk factors for VTE in individuals undergoing high-risk orthopedic surgery. We evaluated the following factors for their significance in VTE causation or association based on the outcomes of these investigations. Age, female gender, smoking history, history of malignancy, prior history of DVT, family history of DVT, varicose vein, obesity, known hormone medication, known thrombophilia, and preoperative duration >7 days are patient-related variables. The use of a tourniquet, the kind of anesthetic used, and the length of the operation (more than 2 h) are all surgery-related variables.
The following risk variables were found to be prevalent in the current study: 46.5% of patients were over 60, with female patients accounting for 66% (32.67%). Out of 202 patients, 33 (16.34%) were smokers, 24 (11.88%) were obese, and 22 patients were diabetic (10.89%). The preoperative stay was more than 7 days, a tourniquet was used in surgery in 27 instances (13.36%), the length of operation was >2 h in 38 cases (18.81%), and the duration of postoperative immobilization was >72 h in 47 cases (22.27%). One hundred and ninety-nine (98.5%) of the 202 patients underwent surgery under regional anesthetic.
In our investigation, the risk variables that were determined to be significant were postoperative immobility for more than 72 h, operation length of more than 2 h, a prior history of DVT, and a preoperative stay of more than 7 days. The existence of comorbid variables such as obesity and diabetes mellitus in one female patient, infection, and the advent of signs and symptoms of DVT in the other two patients might explain the lengthier period of postoperative immobilization in our patients.
DVT patients often have many risk factors, including as immobility, surgery, or trauma. It may be difficult to tell which reason is largely responsible for DVT, and the potential of synergistic effects should never be ruled out.[21]
Age is not commonly regarded as a risk factor. The incidence of thrombosis is linearly proportionate to age, according to Borow and Goldson; (1981)[28] however, Stulberg et al. (1984)[9] observed no such association. Davidson et al.[27] discovered advanced age to be a substantial risk in the postoperative condition, with a 50% rise in the occurrence of DVT every decade of life, but Dhillon et al.[20] discovered no variations in the mean age of patients with and without DVT.
Goldson and Borow (1981).[28] and Dhillon et al.[20] discovered that increasing the time of the procedure is directly proportional to DVT. In our analysis, this was determined to be a substantial risk factor, with a relative risk of 2.21. These findings are analogous to those of Bagaria et al.[24] Dhillon et al.[20] discovered no significant incidence of DVT in relation to operation time.
Male gender has been demonstrated in several studies, such as Davidson et al.[27] and Cogo et al.,[29] to be a risk factor for DVT in patients who have not been operated on. In our research, ladies had a higher incidence of DVT than men. Stulberg et al.[4] discovered female gender to be a major risk factor.[5]
Heit et al.[7] found that neither obesity nor smoking was independent risk factors for DVT, although prior research by Cogo et al.[29] found that obesity and smoking enhanced the risk of DVT. Obesity is a substantial risk factor for DVT, according to Kakkar et al.[30] and Kim et al.[31],[32] According to Anderson and Spencer.,[5] overweight adults, whether defined by weight or BMI, may be at higher risk, although the link between excess weight and VTE is weak.
When the treatment options for 202 individuals were evaluated, 64 instances were treated with intramedullary implants and 138 with extramedullary implants. Thus, the incidence of DVT is 9.37% in patients treated with intramedullary implants and 4.34% in patients treated with extramedullary implants. Mitra et al.[26] discovered a higher incidence of DVT with extramedullary implants.
When all patients' follow-up data were evaluated, 199 (98.51%) had uncomplicated recovery, while two patients died for reasons unrelated to surgery. A solitary instance (0.50%) of re-surgery was performed in the form of debridement owing to infection. One patient (0.50%) was readmitted after 3 weeks owing to worsening discomfort at the operated location, and one case was lost to follow-up.
| Conclusion | | |
Several risk factors lead to the development of DVT. Period of operation >2 h, preoperative stay >7 days, postoperative duration of immobilization >72 h, and prior history of DVT were revealed to be significant risk factors in our research. As a result, we propose that high-risk patients are evaluated for DVT, ideally using color Doppler, since our research demonstrated no difference in specificity and sensitivity between the two. As a result, color Doppler is preferred over venography since it is less intrusive and less expensive.
Age, female gender, tourniquet time, obesity, and other risk variables reported by prior research but not shown to be relevant in our study include because these comorbid variables increase the incidence of DVT, it is advised that these individuals be evaluated.
- We discovered that extramedullary implants had a relative risk of 2.93
- We noticed that clinical signs and symptoms did not help us identify DVT. Only 4 of the 12 DVT-positive people were symptomatic for DVT, while the other eight were asymptomatic and may have gone undiagnosed if not tested for DVT.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1]
[Table 1], [Table 2]
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