J was woken up one morning by the tingling sensation and soreness over her right leg. She was shocked to see that the leg was swollen from the hip down to the ankle. The calf was also tender to touch. Her left leg looked normal.
With the help of her husband, she got up from her bed limping. Realizing that something was amiss, they rushed to hospital immediately.
J, a 32-year-old teacher had delivered her first baby normally two weeks ago. There were no complications during her antenatal period and labour. She was discharged well on the 3rd day after delivery.
On examination, her right leg was swollen from the hip downwards with pitting ankle oedema. The skin on the affected leg appeared bluish red and felt slightly warmer compared to that of her left leg. An urgent ultrasound doppler examination revealed a large blood clot in the deep veins of her leg. J was suffering from a potentially life-threatening condition called deep vein thrombosis (DVT).
What is DVT?
DVT is a condition where blood clots are formed in veins located deep inside the body. A blood clot is a clump of blood that has turned into a solid state.
The blood clots typically form in the thigh or lower leg, but they can also develop in other parts of the body. These blood clots can break loose, travel through the bloodstream and get stuck in the lungs, blocking the blood flow. The condition is called pulmonary embolism and requires emergency care as it can be fatal.
What are the symptoms of DVT?
DVT can occur without noticeable symptoms. According to the Centers for Disease Control and Prevention (CDC) of the USA, symptoms only occur in about 50% of patients.
Common symptoms include:
Swelling in the affected leg. Rarely, there are swelling in both legs.
Cramping pain in the affected leg that usually begins in the calf
A feeling of warmth in the affected leg
Skin over the affected area turns pale or has reddish or bluish coloration
Severe, unexplained pain in the foot and ankle
What are the causes and risk factors of DVT?
Any condition that slows down the blood flow or promotes blood clotting can cause DVT. This may occur when there is:
Damage to a blood vessel’s wall from surgery or trauma
Reduced mobility or inactivity which will slow down the blood flow in the lower extremities.
Inflammation of blood vessels due to infection
Drugs that increase the tendency of blood to clot
Risk factors include:
Pregnancy: Pregnant women are 5 to 10 times more likely to develop DVT than women who are not pregnant. This is because during pregnancy, the levels of blood-clotting proteins increase. Blood flowing back from the lower extremities to the heart also slows down due to compression of the pelvic veins by the expanding uterus. This risk of DVT continues for up to six weeks after delivery as in J’s case.
Prolonged sitting or bed rest
Injuries or surgery
Oral contraceptive pills
Family history of DVT
How is DVT diagnosed?
Besides the signs and symptoms, DVT is usually diagnosed by ultrasound examination of the blood flow of the veins. Blood level of a product of the blood clot (D-dimer) is also raised in almost all patients with severe DVT.
J was referred straightaway to the hematologist who put her on blood thinners (anticoagulant) to prevent the clot from getting bigger and reduce the risk of developing more clots. She also had to wear compression stockings. These stockings reduce the chances of blood pooling and clot forming. With timely intervention, the fatal complication of pulmonary embolism did not occur. The leg swelling gradually subsided after 4 months. She was advised to wear the stockings for 2 years. She is currently being monitored by the hematologist at regular intervals.