Blood and heart physiology, sleep and related conditions

The heart functions as a pump and acts as a double pump in the cardiovascular system to provide a continuous circulation of blood throughout the body. This circulation includes the systemic circulation and the pulmonary circulation. Both circuits transport blood but they can also be seen in terms of the gases they carry. The pulmonary circulation collects oxygen from the lungs and delivers carbon dioxide for exhalation. The systemic circuit transports oxygen to the body and returns relatively de-oxygenated blood and carbon dioxide to the pulmonary circuit. Blood flows through the heart in one direction, from the atria to the ventricles, and out through the pulmonary artery into the pulmonary circulation, and the aorta into the systemic circulation. The pulmonary artery (also trunk) branches into the left and right pulmonary arteries to supply each lung. Blood is prevented from flowing backwards (regurgitation) by the tricuspid, bicuspid, aortic, and pulmonary valves.

Plasma contains 91% to 92% of water and 8% to 9% of solids. It mainly comprises of: Coagulants, mainly fibrinogen, aid in blood clotting. Plasma proteins, such as albumin and globulin, that help maintain the colloidal osmotic pressure at about 25 mmHg.

Some women have high blood pressure during pregnancy. This can put the mother and her baby at risk for problems during the pregnancy. High blood pressure can also cause problems during and after delivery. The good news is that high blood pressure is preventable and treatable. High blood pressure, also called hypertension, is very common. In the United States, high blood pressure happens in 1 in every 12 to 17 pregnancies among women ages 20 to 44.3 High blood pressure in pregnancy has become more common. However, with good blood pressure control, you and your baby are more likely to stay healthy. The most important thing to do is talk with your health care team about any blood pressure problems so you can get the right treatment and control your blood pressure—before you get pregnant. Getting treatment for high blood pressure is important before, during, and after pregnancy.

Getting good sleep isn’t just important for your energy levels—it’s critical for your heart health, too. Learn how sleep is connected to heart health. Sleep is not a luxury. It is critical to good health. Sleep helps your body repair itself. Getting enough good sleep also helps you function normally during the day.

Most adults need at least 7 hours of sleep each night. However, more than 1 in 3 American adults say they don’t get the recommended amount of sleep. While this may be fine for a day or two, not getting enough sleep over time can lead to serious health problems—and make certain health problems worse.

Adults who sleep less than 7 hours each night are more likely to say they have had health problems, including heart attack, asthma, and depression.3 Some of these health problems raise the risk for heart disease, heart attack, and stroke. These health problems include: High blood pressure. During normal sleep, your blood pressure goes down. Having sleep problems means your blood pressure stays higher for a longer period of time.4 High blood pressure is one of the leading risks for heart disease and stroke. About 75 million Americans—1 in 3 adults—have high blood pressure. Type 2 diabetes. Diabetes is a disease that causes sugar to build up in your blood, a condition that can damage your blood vessels. Some studies show that getting enough good sleep may help people improve blood sugar control. Obesity. Lack of sleep can lead to unhealthy weight gain. This is especially true for children and adolescents, who need more sleep than adults. Not getting enough sleep may affect a part of the brain that controls hunger.

Diabetes mellitus refers to a group of diseases that affect how the body uses blood sugar (glucose). Glucose is an important source of energy for the cells that make up the muscles and tissues. It's also the brain's main source of fuel. The main cause of diabetes varies by type. But no matter what type of diabetes you have, it can lead to excess sugar in the blood. Too much sugar in the blood can lead to serious health problems. Chronic diabetes conditions include type 1 diabetes and type 2 diabetes. Potentially reversible diabetes conditions include prediabetes and gestational diabetes. Prediabetes happens when blood sugar levels are higher than normal. But the blood sugar levels aren't high enough to be called diabetes. And prediabetes can lead to diabetes unless steps are taken to prevent it. Gestational diabetes happens during pregnancy. But it may go away after the baby is born.