Contains the full lesson along with a supporting toolkit, including teachers’ notes.
The Age of Medical Devices
In general, any device that is used for medical purposes, whether for diagnosis, treatment or surgery is called a medical device. This definition covers a very wide range of products including X-ray machines, thermometers and wheelchairs. The use of the correct device can have a significant impact, saving lives, extending life span and improving the quality of life for many people. One of the devices that has enriched many lives in the last decade is the stent. In this lesson, we examine the operation of the human cardio-vascular system and some associated medical problems. We then describe how the stent is used and discuss the advent of the most modern drug-eluting stent from Cordis in Co. Tipperary.
Overview of the Human Cardiovascular System
The cardiovascular system is made up of the heart and circulatory system. The circulatory system has two parts. Pulmonary circulation passes through the lungs. Systemic circulationpasses through the remainder of the body.
The heart is often described as a pump. Its function is to circulate blood. This blood plays a crucial role in the maintenance of life. It delivers oxygen and nutrients to the organs, tissues, and cells of the body and removes carbon dioxide and waste products. Oxygenated blood is transported around the systemic circuit from the left heart through a network ofarteries, arterioles (smallarteries), and capillaries. Twenty major arteries branch off into narrower arterioles and these branch off into even smallercapillaries. These capillariesdeliver the oxygen and nutrients. The blood then returns to the right heart through venules (smallveins) which connect to veins.
The right heart then sends this deoxygenated blood through thepulmonary artery to the lungs. Having picked up oxygen from the lungs, the blood returns to the left heart through the pulmonaryveins.