Pressure

Pressure

DEFINE PRESSURE
1. Pressure is an effect when force is applied to any given area
  1. Small area = greater pressure Larger area = less pressure
    1. Pressure = Force/Area
      1. Force= mass x acceleration
    2. Needle has greater force than finger
HOW DO WE MESSURE PRESSURE
1. Pascals Pa or Kilopascals kPA
  1. Notmal air pressure = 101.3kPA Blood gas - 13.3kPA
  2. Blood gases: partial pressure of o2 (Po2) =13.3kPA
2. Brritish units = Pounds/square inch (psi)
  1. Gas cylinders in operating theatres
3. Atmospheric pressure
  1. Messured in Millimetres of mecury
    1. 1Atm = 760mmHg
MEASURING PREESURE IN BODY
1. Blood pressure
  1. Pressure that blood exerts on the wall, measure at teh brachial artery
  2. Systolic blood pressure – first korotkoff sound, when heart is contracting (90-140mm HG)
  3. Diastolic – fifth korotkoff sounds, when heart is relaxing (70-90mmHG)
2. Manometers- Some have water and saline
  1. Cm water and Cm saline - used to record contiuies blood pressure without cuff
Describe and apply the properties of pressure and static liquids
1. Pressure is dependent on the DEPTH of Liquid GREATEST DEPTH =Highest flow rate
2. Pressure is dependant on the DENSITY = GREATEST DENSITY = highest pressure
3. PASCALS LAW
  1. Pressure is exerted equally in all directions in a static liquid - THINK BABY IN BELLY AND FALL

Resource summary

	Created by Clarissa Mackay over 8 years ago

	Copied by abby_levin26 over 8 years ago