Blood is a specialised fluid in the circulatory system of human beings and some other vertebrate animals. It is composed of red blood cells (also called RBCs or erythrocytes), white blood cells (also called WBCs or leukocytes), platelets and plasma. The plasma, which constitutes 55 per cent of blood fluid, is mostly water (about 92 per cent by volume), and contains proteins, glucose, mineral ions, hormones and carbon dioxide (plasma being the main medium for excretory product transportation). the blood cells themselves. Albumin is the main protein in plasma, and it functions to regulate the colloidal osmotic pressure of blood. The most abundant cells in vertebrate blood are red blood cells, which give blood its red colour. These contain haemoglobin, an iron-containing protein, which facilitates oxygen transport by reversibly binding to this respiratory gas thereby increasing its solubility in blood. In contrast, carbon dioxide is mostly transported extracellularly as bicarbonate ion transported in plasma.
Blood has many different functions, including, transporting oxygen and nutrients to the lungs and tissues. forming blood clots to prevent excess blood loss.
What’s a clot?
It’s a clump of cells and protein in your blood. A clot helps slow bleeding when you’re injured. It usually dissolves as you heal. But if it doesn’t, or if it forms when it’s not needed, it can clog up or completely block a blood vessel.
What problems can it cause?
An unexpected clot can lead to serious problems and even death. In an artery, it can give you a heart attack or a stroke. If it happens in a vein, you can feel pain and swelling. A clot deep inside your body is called a deep vein thrombosis (DVT). One in your lungs is a pulmonary embolism (PE). They’re both medical emergencies.
Know your chances
You can get a blood clot if you break a bone or pull a muscle badly. But sometimes you may not know why it happened or even realize you have one. There are clues though. Your odds of a clot are higher if you:
Are recovering from surgery or had to sit for many hours on a flight or in a wheelchair
Are overweight or obese
Have diabetes or high cholesterol
Are over 60
Signs of a clot
Swelling: When a clot slows or stops the flow of blood, it can build up in the vessel and make it swell. If it happens in your lower leg or calf, it’s often a sign of DVT. But you also can have a clot in your arms or belly. Even after it goes away, one in three people still have swelling and sometimes pain and sores from damage to the blood vessel.
Skin colour: If a clot plugs up veins in your arms or legs, they may look bluish or reddish. Your skin also might stay discoloured from the damage to blood vessels afterwards. A PE (pulmonary embolism) in your lung could make your skin pale, bluish, and clammy.
Pain: Sudden, intense chest pain could mean the clot has broken off and caused a PE. Or it could be a sign that a clot in your artery gave you a heart attack. If so, you also might feel pain in your arm, especially on the left. A clot often hurts where it’s located, like in your lower leg, stomach, or under your throat.
Trouble breathing: This is a serious symptom. It could be a sign that you have a clot in your lung or your heart. Your heart might also race, or you may feel sweaty or faint.
Location: Lung
Effect of location of clot
Lung: A clot can give you different symptoms based on where it is. A PE can give you a fast pulse, chest pain, bloody cough, and shortness of breath. Get to the hospital right away. You also might have no signs.
Heart: This can feel similar to a clot in the lung. But if it’s a heart attack, you also might feel nausea Brain: Pressure builds when blood can’t flow normally. A severe blockage sometimes can lead to a stroke. Without oxygen from the blood, your brain cells start to die in minutes. A clot in your brain can cause headaches, confusion, seizures, speech problems, and weakness, sometimes on just one side of the body.
Belly: Often, you have no symptoms at all. Blocked veins in the stomach or oesophagus, a tube that connects it to your throat, can rip and leak blood. That can hurt a lot. You may poop or vomit blood, and your stool might look black and smell unusually bad.
Kidneys: Also called renal vein thrombosis, these clots usually grow slowly and mostly in adults. You probably won’t have symptoms unless a piece breaks off and lodges in your lung. Rarely, especially in children, it can happen fast and cause nausea, fever, and vomiting. You also might have blood in your pee and go less often.
What to do if you suspect a blood clot
See your doctor or go to the emergency room right away. A clot can be deadly, and you won’t know for sure you have it until you get checked. Your doctor may give you a clot-busting drug or surgically thread a thin tube to the site of the clot to dissolve it.
Prevention tips
You can act to lower your odds of a clot. First, keep a healthy weight, eat right, and exercise. In addition, you should not sit or stay still for long, especially after a long trip or surgery. If you’re a desk jockey, get up and move at least every couple of hours. Flex your legs, feet, and toes in your chair.
Check if tight-fitting compression socks or garments can help your blood flow. Ask your doctor if you might need to take clot-fighting drugs called anticoagulants.
• Adapted from webmd.com
