Introduction:
Hip and knee replacement surgeries are one of the most commonly performed surgeries around the globe. It is done to improve a person's walk and function and is considered one of the most life-changing surgeries. However, there is always a chance of dislodgement of clots or clotting fragments released into the system when removing the soft tissues or smoothing the bony part, which further induces thromboembolism. Thromboembolism is the obstruction of a blood vessel by a blood clot dislodged from another site of the body. Venous thromboembolism is a clinical condition characterized by blood clots in the veins, which can result in serious complications when left undiagnosed.
How Commonly Does Venous Thromboembolism Occur?
Venous thromboembolism is a common complication while performing a hip and knee arthroplasty. The incidence of venous thromboembolism is around 1.5 percent of patients even after following the prophylactic drug within three months of the postoperative period.
What Are the Methods of Preventing Venous Thromboembolism?
The doctors and the surgical team take a lot of care in preventing the dislodgement of an embolism from occluding the blood vessels. Various methods reduce the risk of ventricular thromboembolism, but the concern for potential bleeding is always a possibility. Various cautions and measures are taken to achieve this, and they are:
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General Medical Management: The first line of management is achieved by putting the patients on medications. These are steps done while operating on the patient. The injured part is removed as quickly as possible with care followed by full surgical procedures and establishing adequate hydration during surgery.
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Mechanical Management: This is a non-surgical way of preventing ventricular thromboembolism. Patients are asked to wear a compression stocking, while for patients undergoing complete knee arthroplasty (it is the procedure in which the worn-out knee cartilages are trimmed), mechanical foot or calf compressors provide easy backflow of the blood and prevent dislodgement of the clot. However, these compressors can be expensive, making it difficult for patients to afford them.
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Choice of Anesthesia: The choice of anesthesia used while performing the procedure can also affect the thrombus. The anesthesia generally preferred is neuraxial anesthesia, which is preferred to be given using a spinal or epidural catheter to reduce nerve bleeding, especially when an anti-clotting medication is given side by side. It is important to follow the timing and dosage guidelines for anesthesia.
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Anti-Blood Clotting Medications: Anti-blood-clotting medicines act on the blood, thinning it out and reducing the blood pressure preventing the clotting of blood.
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Older Medications: The older blood clotting medicines that were widely used are Aspirin and Warfarin. But these drugs had certain drawbacks, like Aspirin being a weak clotting agent while Warfarin needs regular monitoring, is expensive, and is very time-consuming to show the effect.
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Newer Medications: With the emergence of developing medicine, newer blood clotting drugs are preferred. These drugs have the benefit of administering both orally and intravenously. Although these drugs are essential, there is no direct comparison between the older and newer drugs.
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Injectable Medications: Heparin is the preferred drug of choice and is used as an injectable anti-clotting medication.
How Is Venous Thromboembolism Surgically Managed?
Venous thromboembolism is surgically managed by treating the patient with a less strenuous and minimally invasive procedure. Surgical management is done by minimally invasive and less traumatic techniques. These minimally invasive surgical procedures include laparoscopy or arthroscopy, where a fiber-optic camera is inserted by making a small lesion and is operated by micro instruments controlled by the surgeon externally with the help of camera visuals, where the tissue tear is less, which in turn causes fewer fragments of the blood clot that prevent occlusion in the blood vessels.
What Are the Guidelines to Be Followed to Prevent Venous Thromboembolism?
A diagnostic workup is made before treating the patients when venous thromboembolism is suspected, as per the prophylaxis guidelines given by the American Academy of Orthopedic Surgeons.
The use of Aspirin is avoided before the surgery. The use of anti-clotting medications or compression bands is generally advised after surgery. However, those with a higher risk of thromboembolism should use both chemical and mechanical methods, whereas patients with a higher risk of bleeding are put on mechanical compressions.
The other clinical guidelines provided by the European Society are:
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A balanced treatment approach is to be followed. This is done by proper clinical assessment, treatment plan, and discussing the cost value.
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Choosing the correct combination of treatment: Both mechanical and chemical treatments are provided, but a correct knowledge of the treatment and to whom it is used should be considered.
How Is a Venous Thromboembolism Diagnosed?
Venous thromboembolism can be diagnosed by the following methods:
Duplex Ultrasonography: The most common method for diagnosing an embolism is through a procedure called duplex ultrasonography. Duplex ultrasonography is a method of imaging technique used to test the movement of the blood in deep veins using sound waves. This is especially used for detecting blockages in the veins or blood clots circulating in the system.
D-dimer Blood Test: A D-dimer blood test is a type of blood test that measures the amount of blood released when a clot breaks. This test is done to measure the output of fragments broken during thromboembolism.
Contrast Venography: It is a special type of radiographic imaging where a dye is injected into the veins of the leg, in the foot, or ankle and is monitored till the circulation in the hips is completed. This is used to assess the presence of any clot or obstruction in the veins.
Magnetic Resonance Imaging (MRI): Magnetic resonance imaging is a three-dimensional test that uses magnetic waves to image soft tissues. This is an imaging technique that helps to study soft tissues using sound waves. The test provides images of clots or embolisms located in the veins.
Conclusion:
Venous thromboembolism associated with total knee arthroplasty and hip arthroplasty is a very commonly occurring condition, but with the developing improvements in medications, a significant decline in the incidence of venous thromboembolism is seen. Along with medical management, an adaptation of new surgical management methods has also played a significant role in the reduction of the rate of venous thromboembolism.
