ECGS and X-rays Flashcards
What is kinetic energy formula
1/2 mass x velocity squared
Charge of electron x voltage
What is the inverse square law
The intensity is 1 over the square of distance from the source
What makes a material good for absorbing radiation
The thickness and density of the material
What are cats ans and how do they work
They are a form of taking x rays. The patient is in a tube and the exray source is moved around in a circle around the patient. The detector moves opposite the source. Using a computer, a cross section image of the patient can be taken.
What is a fluoroscope
An x ray sourçe and digital detector. The patient is placed in between to make live images of the inside of the patient
Risks and benefits of cat scans and fluoroscope
Benefit
Painless and non invasive
No need for biopsy surgery
Cons
The radiation dosage is 10x the yearly background radiation dose
What is an action potentials
An electric signal sent to muscles to tell them to contract
How can egcs detect action potentials
Body is made up of lots of salty water, this means the body is a good conductor so the action potentials can travel through the body to the skin where they egg detected
What is the order of action potentials in the heart
Starts in atria, spreads to ventricles then to the base of the ventricles.
How does a pulse oximeter work and what does it do
Out over the tip of the finger. Two leds are shone through, a red light and an infrared light. On the other side of the finger is a detector. When the heart beats, it pushes oxygenated blood around the body. Oxygenated blood absorbs more infrared light and de oxygenated absorbs more red light. By detecting which light comes through, the pulse can be measured. It can also work out the percentage of O2 in the blood by comparing the absorbante of the red and infrared light
What does a pace asker do
They are put into people whos action potentials don’t spread through the heart well. The pacemaker detects the action potential and amplifies it so the heart beats correctly.
