Year : 2019 | Volume
: 12 | Issue : 2 | Page : 150--154
WACEM consensus paper on deep venous thrombosis after traumatic spinal cord injury
Boris Vladimir Cabrera Nanclares1, Huber Said Padilla-Zambrano1, Ayman El-Menyar2, Luis Rafael Moscote-Salazar3, Sagar Galwankar4, Ranabir Pal5, Amrita Ghosh6, Amit Agrawal7, Mendoza-Flórez Romario1,
1 Centro De Investigaciones Biomédicas, Cartagena Neurotrauma Research Group Research Line, Faculty of Medicine, University of Cartagena, Cartagena De Indias, Colombia
2 Department of Clinical Medicine, Weill Cornell Med College, Doha, Qatar
3 Neurosurgery-Critical Care, Red Latino Organizacion Latinoamericana De Trauma Y Cuidado Neurointensivo, Bogota, Colombia
4 Department of Emergency Medicine, Sarasota Memorial Hospital, Florida State University, Florida, USA
5 Department of Community Medicine, MGM Medical College and LSK Hospital, Kishanganj, Bihar, India
6 Department of Biochemistry, Medical College, College Street, Kolkata, West Bengal, India
7 Department of Neurosurgery, Narayana Medical College Hospital, Nellore, Andhra Pradesh, India
Dr. Amit Agrawal
Department of Neurosurgery, Narayana Medical College Hospital, Chinthareddypalem, Nellore - 524 003, Andhra Pradesh
The risk and outcome of deep vein thrombosis (DVT) in patients who sustained spinal cord injury (SCI) remain a challenge. We aimed to assess the incidence, risk, burden, and prophylaxis of DVT after SCI. Thirty-nine studies were identified from among 250 relevant articles based on firstly, broad criterion of DVT among SCI cases. secondly, “risk factors” impacting DVT, thirdly, published reports from apex bodies of global importance such as World Health Organization, Centre for disease control, Atlanta USA, and others were given due weightage for their authenticity. SCI is characterized by loss of motor, sensory, and autonomic function with partial or total damage of the anatomical structure leading to increased risk of thrombogenesis. SCIs present a higher risk of venous DVT constituting 9.7% of deaths in the 1st year of follow-up. Currently, prophylaxis with mechanical methods, vena cava filters and antithrombotic chemoprophylaxis in SCI are interventions for the management of DVT. DVT in SCI patients is not uncommon and needs a high index of suspicion and implementation of institutional prophylaxis protocol.
|How to cite this article:|
Nanclares BV, Padilla-Zambrano HS, El-Menyar A, Moscote-Salazar LR, Galwankar S, Pal R, Ghosh A, Agrawal A, Romario MF. WACEM consensus paper on deep venous thrombosis after traumatic spinal cord injury.J Emerg Trauma Shock 2019;12:150-154
|How to cite this URL:|
Nanclares BV, Padilla-Zambrano HS, El-Menyar A, Moscote-Salazar LR, Galwankar S, Pal R, Ghosh A, Agrawal A, Romario MF. WACEM consensus paper on deep venous thrombosis after traumatic spinal cord injury. J Emerg Trauma Shock [serial online] 2019 [cited 2021 Nov 28 ];12:150-154
Available from: https://www.onlinejets.org/text.asp?2019/12/2/150/259191
Spinal cord injury (SCI) has been considered a public health problem because patients require treatments throughout their lives, which generates an increase in costs in health services, loss of employment and a negative impact on the family nucleus. Globally, the prevalence of SCI is 12,000 cases per year,, an incidence between 5% and 63% and has high mortality rates., This has prompted the study and implementation of measures that contribute positively in the intervention of these patients, such as antithrombotic prophylaxis, which has become a useful pharmacological treatment for the prevention of the development of venous thromboembolism reduces mortality., We aim to describe the incidence, risk, burden, and prophylaxis of deep vein thrombosis (DVT) after acute SCI.
We conducted a traditional review of the potentially relevant articles. Studies were selected on, First; broad criterion of DVT among SCI cases. Second, “risk factors” impacting DVT were identified, thirdly, published reports. The terms employed in the search were: “SCI,” “DVT,” “thromboembolism,” “injury,” and they were combined using Boolean operators. Each author's search results were merged, and duplicate citations were discarded. The search was performed aiming at those studies comparing outcomes of DVT. No language restrictions were applied. We searched for, and assessed studies of SCI with and without DVT. No limitations were applied on ethnicity, the age of patients or interventions. Three authors independently reviewed the abstracts and articles. In addition, the reference lists of all relevant articles were scrutinized as well to find cross-references. For the purpose of this analysis, the eligible studies were independently evaluated by all coauthors for inclusion or exclusion from this analysis. In inclusion, baseline characteristics, methods of intervention, and outcomes were not considered. Data were independently collected by two investigators and checked by one-third investigator only from the retrieved articles. Disagreement on collected data was settled by consensus between these investigators. No any attempt was made to obtain specific or missing data from the authors. The following data were extracted:first author, year of publication, study design, number of patients, type of procedure, and primary and secondary measures. The primary outcome measure was the DVT in SCI. Secondary outcomes were interventions. All outcomes obtained from the studies used same parameters.
Epidemiology of spinal cord injury
The lesion at the medullary level is an entity that presents a cosmopolitan distribution. Although there is no reliable estimate of global prevalence, estimated annual global incidence is 40–80 cases per million population (12,000 new cases per year), up to 90% are due to trauma, though nontraumatic SCI appears to be growing.,
In countries, such as the United States, an incidence of 30–50 cases per 1 million inhabitants/year has been estimated. In the developing countries like India, Pakistan, Bangladesh, etc., there is an absence of national spinal injury programs or SCI registries resulting to population-based data. Indian estimates suggested incidence around 15–20 per million per year population.
Among the most frequent causes are accidents of automobile type, sports, injuries related to occupation, injuries by firearms and falls in the home,, with a higher prevalence in males with an age group corresponding to middle and young adults. Spinal cord injuries are more frequent in the thoracolumbar region and nearly half have outcomes of tetraplegia and paraplegia.,,
Pathophysiology of venous thromboembolism
Several models with numerous risk factors have been postulated for pathophysiology of venous thromboembolism in SCI. Bleeding in the spinal trauma begins in an early period, followed by interruption of the flow, leading to complications such as hypoxia, ischemia and finally localized infarction.,,, Causing edema and decreased nerve myelin causing deterioration of impulses., Further, there may be lack of energy due to cellular alteration due to hypoperfusion and ischemia which precipitates an oxidative type damage, elevation of glutamate levels, lipid deterioration by free radicals and reactive oxygen species, and excitotoxicity. All of the above causes a cascade of cellular injury, which is the fundamental basis of spinal cord damage., Conventionally, SCI, brain injury, pelvic fracture, and prolonged immobilization have been associated with this complication. Under the aegis of the American College of Surgeons, Knudson et al. could find six factors played their roles among 450,375 patients, significantly to develop thromboembolism, namely, surgical procedures, age over 40 years, venous injury, need of mechanical ventilation >3 days, brain injury, and more than three simultaneous fractures. Another transcendental point described in the literature is that SCI independently increases the risk of venous thromboembolism in patients.
Incidence of venous thromboembolism
The incidence of venous thromboembolism as a complication in SCI is quite high. Depending on the different diagnostic methods used, age of the patient, characteristics of the lesion, the event rate varies from 7% to 100% in different series of studies who did not receive antithrombotic prophylaxis or who received antithrombotic prophylaxis. Inadequate form., According to Teasell et al., the incidence range varies from 9% to 100%. Fujii et al. noted that the overall incidence of DVT in their series with SCI was around 57%. Venous thrombosis generates approximately 9.7% of deaths in the 1st year of follow-up in patients with SCI.,
Pathogenesis of venous thromboembolism
Thrombogenesis as a physiopathological process has been attributed for many years to the well-known Virchow triad (blood stasis, hypercoagulability and endothelial damage). The injuries considered major usually precipitate or amplify one of these three mentioned factors, propitiating states of hypercoagulability, leading to thrombogenesis as a complication. Owings et al. state that patients with trauma and especially with spinal cord injuries increase the probability of leading to an increased risk of thromboembolism.
Direct vascular injury could cause endothelial damage that can lead to thrombosis, added to this, lasting bed rest, immobilization as a complication, decreased perfusion, and paralysis increase the risk of venous stasis and consequently of thrombogenesis. Another proposed aspect is the decrease in antithrombin III values and the decrease in fibrinolysis in trauma patients. Okamura et al. and Peetz et al. found in their studies that levels of d-Dimer were higher in patients with various injuries. In addition, certain surgical-type procedures and to a greater extent, SCI, are highly related to an extremely high risk of postoperative thromboembolism.,
Clinical presentation for suspicion of venous thromboembolism
In the world literature, the term venous thromboembolism is used to describe two variants: thrombophlebitis and phlebothrombosis. This term of DVT was instituted for the first time Ochsner and DeBakey. Thrombophlebitis as an entity is the term used to describe a process of inflammatory thrombosis which is characterized by the presence of edema, febrile processes, inflammation, local hyperemic area, distal cyanosis, hyperesthesia, and congestion at the superficial venous level., Phlebothrombosis was the term described to characterize an asymptomatic thrombotic process. Within this process, a soft clot is described, which is not adherent to the walls of the vessel. To suspect a venous thromboembolism, a series of clinical signs must be taken into account. Within these signs are described: asymmetric edema between both legs (>1.5 centimeters that difference), hyperemic zone located next to the edema, sign of Homans (increased irritability and spasticity in the area), inflamed superficial veins, palpable induration, and sudden dyspnea accompanied by confusion and acute chest pain.
Clinical pretest probability for venous thromboembolism
The diagnostic impression of DVT begins with a pretest evaluation with clinical pretest probability (CPTP). This is greater if: (1) The signs and symptoms are consistent with the DVT clinic, (2) There are risk factors for DVT, (3) It is considered that DVT is the most likely diagnostic impression. The use of these pretest is facilitated, by the association with clinical prediction instruments such as the Well scale and the Geneva scale are widely used and validated. CPTP generally has a classification based on categories such as low probability, medium probability, or high probability, or it is classified as unlikely or probable., It must be taken into account that only with the CPTP can the diagnosis of DVT be discarded. The CPTP allows us to guide the use of additional tests (confirmation tests if it is probable or exclusion if it is unlikely), in addition it increases the diagnostic accuracy before the DVT.,,
What posttest probability “rules-in” or “rules-out” venous thromboembolism
Rules-in deep vein thrombosis
Usually, a high level of certainty is required to have a diagnosis of DVT. This is because the diagnosis of this entity leads to a psychological burden on the part of the patient and to a treatment with a series of inherent complications. Depending on the test used, cutting points will be taken to consider a more accurate diagnosis., For example, when the main test that was used for the diagnosis of pulmonary thromboembolism was ventilation-perfusion, a probability of ≥85% is considered as diagnostic certainty, that is, it corresponds to what is considered a very high probability exploration, which justifies the diagnosis and treatment.
Rules-out deep vein thrombosis
Just as a high level of certainty is needed to decide a diagnosis, so high certainty is needed to decide that an entity is not established. In the case of DVT, there must be great certainty, since it is associated with complications that increase morbidity and can lead to death. The level of certainty that excludes the diagnosis of DVT and justifies the suppression of both treatment and additional diagnostic tests, it is accepted that it is a probability ≤2%., A probability ≤2% of DVT indicates during follow-up: (1) It is similar to that observed after a pulmonary angiography and a negative venogram, (2) It is acceptable for the large number of patients and doctors, and (3) It is low enough for that when performing other additional tests there is some possibility of diagnosis.,,
Prophylaxis of venous thromboembolism in patients with spinal cord injury
Patients in the context of thromboprophylactic absence and SCI increase the likelihood of venous thromboembolism, compared to any other group of hospitalized patients. Adding to the problem of the increased risk of venous thromboembolism, we add another challenge characterized by the silent clinical thrombotic development resembling any other complication or medical eventuality.
The use of prophylactic measures in SCI patients is controversial as there are doubts based both on the effectiveness and safety of these measures on the individual. Due to these doubts, during the last years multiple clinical trials designed to evaluate the effectiveness and safety of these measures has been developed, making recommendations and promoting the individuality of the cases and the patient.
Several reviews of the world literature suggest that patients who have sustained SCI particulary with neurological deficits and who are planned for long and complex surgical procedures and also have known thromboembolic risk factors (paralysis, hypercoagulable state), should be considered for the use of postoperative chemoprophylaxis. However, prophylaxis of mechanical type (including boots or compression stockings, sequential pneumatic compression) would be indicated for any spinal surgery in patients who are hospitalized, due to the low rate of complications of these devices.
Prophylaxis with mechanical methods
Various kinds of external compression devices are commercially available that can be used for prophylaxis against venous thromboembolism in patients in immobile condition. These devices base their mechanism of action on the reduction of the diameter at the venous luminal level, which results in an increase in the flow velocity. They have an advantage characterized by ease of use and a much lower risk of bleeding compared to chemoprophylactic methods.,
Prophylaxis with vena cava filters
The vena cava filters (VCFs) were implemented and designed for the first time in the decade of the sixties, their design has progressively improved and their use has been increased nowadays. Its principle of action is based on a device in the form of a cone or network that is implanted at the level of the inferior vena cava, located in inferior portions of the renal vein outlet, by means of a percutaneous approach. Its indications include patients with a registered thromboembolic disease, with a contraindication to anticoagulant therapy (enteric bleeding, profuse bleeding).,, A second indication for this method is those patients with thromboembolic injury and a history of multiple pulmonary thromboembolism.,, Unfortunately, VCFs are not risk-free, because they do not protect the transient nature of the hypercoagulability states, so some surgical procedures have devalued their use. However, multiple authors have highlighted the importance of the placement of these devices in patients at high risk of thromboembolism. Within the world literature, there are various reports on the prophylactic use of VCF in patients with trauma, within which there is a decrease in the incidence of pulmonary embolism. Khansarinia et al. found significant data on mortality reduction due to pulmonary thromboembolism in high-risk patients.
Chemoprophylaxis antithrombotics in patients with spinal cord injury
With respect to pharmacological management, it has been widely established that low-molecular-weight heparins (LMWHs) are preferable for unfractionated heparins in the population of patients with SCI, due to the duration of their half-life, which is longer. LMWHs have a lower probability and a lower risk of hemorrhagic complications and have a more predictable effect with respect to their dose compared to other heparins. Another advantage of these heparins is that they present more efficient absorption in subcutaneous tissues, less variability in response, which translates into less need for extra dosages, or supervision by laboratories., In addition to the above, it has an antithrombotic effect equivalent to other heparins with a lower risk of bleeding. With respect to the rates of complications related to LMWH, these are lower (1.6%–10%), even when antithrombotic prophylaxis is restarted 24 h after surgery.,,
It has been found that several clinical trials guarantee the use of LMWH. The thromboprophylaxis research group in patients with SCI performed a randomized controlled clinical trial in which the use of unfractionated heparin and intermittent measures of compression versus LMWH was compared, following the same lines of administration. Among its results, the rates of thromboembolic symptoms were only 1.7% in patients treated with LMWH and the probability of bleeding was reduced by 14.8%.
Ideal time to start antithrombotic chemoprophylaxis
Several authors suggest that the ideal time to start chemoprophylaxis is immediately after the injury occurs or in a very short time lax after the event occurs. With this approach of immediate initiation of chemoprophylaxis several problems arise. First the patients with acute spinal injury are in constant operative procedures and second several studies have demonstrated the low incidence of venous thromboembolism in the first 3 days after the injury. Aito et al., conducted a study comparing two groups of patients (prophylaxis within the first 72 h versus late prophylaxis 72 h later and showed an incidence of thromboembolism within the first 60 days of 2% for the early prophylaxis group and 26% for the late prophylaxis group. Green et al. conducted a study based on the comparison of two groups with early onset of prophylaxis (before 72 h). Differentiated by the implementation of LMWH and fractionated heparin. They found a rate of venous thromboembolism of 10% after 8 weeks, with fewer complications in the group where LMWH was implemented compared to the other group studied.
When to stop chemoprophylaxis?
Patients with SCI are subjected to multiple stabilization and surgical procedures., These procedures temporarily require that the anticoagulant agents be stopped to prevent possible hemorrhagic complications., Multiple studies recommend the suspension of anticoagulant therapy 24 h before the surgical procedure, due to the possible lasting effect of heparin., Contrary to this findings, other researchers opined that by bridging therapy with a short-acting anticoagulant, namely LMWH, during the time when a long-acting anticoagulant administration (CF warfarin), may be withheld preoperatively till postoperative days when long-acting anticoagulant is resumed within the target therapeutic range. Due to the increased risk of thromboembolism in SCI patients, the resumption of prophylaxis was justified 6 h in the postoperative period. During this period of cessation, it is recommended that mechanical prophylaxis devices be applied.,
DVT in SCI patients is not uncommon and needs high index of suspicion and implementation of institutional prophylaxis protocol.
Implications of spinal cord injuries are generally overlooked and underestimated considering high burden in global health care delivery system. With a higher prevalence in males in the productive age group, SCIs present a higher death risk of DVT up to 10% in 1st year follow-up. At present, prophylaxis with mechanical methods, VCFs and antithrombotic chemoprophylaxis in SCIs are among vital interventions. Anticoagulant therapy is endorsed 24 h after surgery and postoperative prophylaxis continued for 6 h.
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Conflicts of interest
There are no conflicts of interest.
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