Circulatory and immune system

• The Heart


  • It is a powerful organ responsible for pumping blood throughout the body
  • It is made up of four chambers, each with a unique function
• Blood Vessels


  • They include arteries, veins, and capillaries, each with a different function in maintaining adequate blood flow
• Blood cells


  • Red blood cells
  • White blood cells
  • Platelets
• How Blood Circulates in the Body

  1. Pulmonary Circulation - The circulation that carries deoxygenated blood from the heart to the lungs and oxygenated blood back to the heart

  2. Systemic Circulation - The circulation that carries oxygenated blood from the heart to the body and deoxygenated blood back to the heart

  3. Coronary Circulation - The circulation that supplies oxygen and nutrients to the heart itself through its own blood vessels
• Red Blood Cells - Erythrocytes


  • Transport oxygen from lungs to heart and around the body and some carbon dioxide to the lungs
  • Contain haemoglobin (Hb) which is a red protein that combines with oxygen
  • No nucleus; allows them to contain more oxygen
  • Biconcave in shape to give greater surface area for maximum oxygen absorption
  • They are small and flexible to fit through narrow blood vessels
  • Formed in the bone marrow
• Normal Red Blood Cell Count

  • Adult Males: 13.5-18 g/dl
  • Adult Females: 12-15 g/dl
  • Children: 11-16 g/dl
  • Pregnancy: Typically above 10 g/dl
• If someone has a low haemoglobin level

  They might be tired, tire easily, feel cold, have headaches, be breathless on movement and feel light headed
• What might be done for someone with a low Hb?

  1. Eat iron rich foods

  2. Iron or B12 supplements

  3. In severe cases a blood transfusion might be necessary
• Haemoglobin Disorders


  • Anaemia - Low Hb
  • Polycythemia - High Hb
• Platelets - Thrombocytes


  • Small discs with no nuclei
  • Lifespan of 8-11 days
  • Blood clotting, secreting clotting factors, vasoconstricting agents to cause vascular spasm
  • Form platelet plugs
  • Also dissolve old blood clots, destroy bacteria and attract neutrophils and monocytes to infected sites by chemical messages
  • Formed in the bone marrow
• White Blood Cells - Leucocytes

  • Granulocytes
  • Agranulocytes
• Immune System


  • It is made up of various organs, cells, and proteins that work together to defend the body against infections and diseases
• White Blood Cells


  They are the key players in the immune system and are responsible for recognizing and fighting off foreign invaders such as bacteria, viruses, and cancer cells
• Phagocytes


  A type of white blood cell that engulf and destroy foreign invaders to protect the body from infection
• Immune System Defence Mechanisms

  1. Innate (Natural) Immune Response - A general defense mechanism that's always active, providing immediate protection against infections

  2. Adaptive Immune Response - A specific defense mechanism that's activated when the innate immune response is overwhelmed. It involves the production of antibodies and the activation of T and B cells to fight off specific invaders

  3. Memory Cells - Specialized cells that "remember" a previous encounter with a specific antigen and can quickly mount an immune response if exposed to it again, providing long-term protection
• Antibodies


  Proteins produced by the immune system that can recognize and neutralize specific invaders such as bacteria and viruses
• T Cells


  Specialized immune cells that recognize and destroy cells infected with viruses and some types of cancer cells
• B Cells


  White blood cells that produce and release antibodies to neutralize invaders
• How do Antibiotics Work?

  • Kill or slow down the growth of bacteria
  • Attack the cell wall
  • Interfering with bacteria reproduction
  • Blocking protein production of the bacteria
  • Antibiotics cannot kill viruses
• Blood Pressure


  The force of the blood against the walls of the blood vessels. High blood pressure can pose health risks such as heart failure, stroke, and kidney disease
• How to Measure Blood Pressure?

  1. The best way to monitor blood pressure is through a blood pressure cuff or machine

  2. It's typically measured using two numbers: systolic pressure (when the heart is contracting) and diastolic pressure (when the heart is resting)
• Tips to Maintain Healthy Blood Pressure Levels

  Lifestyle changes such as eating a balanced diet, regular exercise, maintaining a healthy weight, and managing stress can help maintain healthy blood pressure levels
• Monitoring Blood Pressure


  1. Inform patient and seek consent

  2. Ensure the patient has been sat/resting for at least 5 minutes

  3. Ensure legs are uncrossed

  4. Place cuff on the arm

  5. Have arm in line with heart

  6. Advise the patient to relax and advise not to talk

  7. Press Start and wait for cuff to deflate fully

  8. Record and report readings
• Normal Range for Blood Pressure

  • 90/60 – 120/80
  • High BP = over 140/90 (hypertension)
  • Low BP = below 90/60 (hypotension)
  • Babies & Children have lower BP than adults
• Maintaining a healthy circulatory and immune system

  • Can lead to a reduced risk of heart disease, stroke as well as other illnesses related to poor circulation and weakened immune systems
  • Can deliver oxygen and nutrients to all parts of the body, leading to an overall increase in energy and vitality
  • Can help manage stress and reduce the risk of chronic stress-related diseases