It can be serious. It may make your leg hurt and swell. The clot might move and get stuck in a blood vessel in your lungs, brain, or heart. That could cause organ damage and even death -- within hours.
You're more likely to get a clot after any surgery that reduces blood flow to a part of your body or after major surgery on your legs, belly, or chest. That includes orthopedic surgery, such as a hip replacement, and abdominal surgery where you'll be under general anesthesia for more than 30 minutes.
The procedure could set tissue, protein, and fats loose in your veins. If the wall of a vein gets accidently damaged, it can release chemicals that trigger blood clotting.
Following major surgery, you'll probably be on bed rest. You won't be using your leg muscles, and that slows your blood flow.
Medical Conditions and Treatments
DVT can happen at any age, but being older than 60 makes it more likely.
Any illness that puts you in bed for more than 3 days can set you up for DVT. And if you've had circulation or clotting problems before, you could have them again.
These are some of the most common medical risk factors for DVT:
- An injury that lessens blood flow, such as a broken pelvis, hip, or leg
- Some cancers and cancer treatments
- DVT or pulmonary embolism in the past
- An inherited blood-clotting disorder
- Hormone therapy, for birth control or postmenopausal symptoms
- Pregnancy or recently giving birth, especially by C-section
- Varicose veins
- Previous heart attack, stroke, or congestive heart failure
- Inflammatory bowel disease
Your Lifestyle and Habits
When you spend a lot of time sitting or don't move much, like on a long plane flight or a long car trip, blood tends to settle in your legs.
Extra weight will put extra pressure on the veins in your lower body, which makes it harder to move the blood.
Smoking affects both circulation and clotting.
Although it's rare, you can get DVT in your upper body, too. A few things that can raise your chances are:
- Having a long, thin, flexible tube (catheter) in an arm vein
- Getting a pacemaker or implantable cardioverter defibrillator (ICD) for certain heart conditions
- Cancer near a vein
It's very unlikely, but overworking the muscles in your arms over time might lead to a clot in them.