The Human Heart (Circulatory System)

Some interesting facts regarding the Human Heart.

1. It is the central organ of the cardiovascular system
2. It is a hollow, muscular organ that contracts at regular intervals, forcing blood through the circulatory system
3. It is cone-shaped
4. It is about the size of a clenched fist
5. It lies between the lungs and behind the sternum
6. It is tilted slightly towards the left
7. It is enclosed within a protective membrane known as pericardium whose task is to maintain lubrication of the heart to reduce friction during beating of the heart
8. The right side of the heart pumps blood (Darker shade of red) from the body into the lungs (Deoxygenated Blood)
9. The left side of the heart pumps blood (Brighter shade of red) from the lungs to the rest of the body (Oxygenated Blood)
10. The left side of the heart is thicker than the right side of the heart
11. The left side of the heart is 5 times more powerful than the right side of the heart
12. Veins in the body contains deoxygenated blood
13. Arteries in the body contains oxygenated blood
14. Veins in the heart contains oxygenated blood
15. Arteries in the heart contains deoxygenated blood
    

How does the blood flow within the heart?

I will divide the heart into the Left and Right portions. From the Left, it comprises of aorta, left atrium and left ventricle. From the Right, it is made up of pulmonary trunk, right atrium and right ventricle.

The Right Atrium receives De-Oxygenated Blood from the body via the Superior and Inferior Vena Cava. The blood is then pumped into the Right Ventricle via the Tricuspid Valve. It will flow through the Pulmonary Semi-Lunar Valve into the Pulmonary Artery. The deoxygenated blood will be carried by the pulmonary artery to the lungs to be replenish with Oxygen via Gas Exchange. Oxygenated Blood are brought back to the heart by Left and Right Pulmonary Veins into the Left Atrium. The blood goes through the Mitral Valve (aka Bicuspid Valve) into the Left Ventricle. It will then pass through the Aortic Semi-Lunar Valve into the Aorta (biggest artery in the body) before it begins the journey throughout the rest of the body through the vast networkof arteries.

The Picture below depicts the route I had written above:-

The Cardiovascular System consists of 2 circuits. They are the "Pulmonary Circuit" and "Systemic Circuit". The pulmonary circuit carries blood to and from the lungs. The systemic circuit transports the blood to and from the body.

The above picture shows another diagram of the heart. This picture is extracted from Wikipedia, the free online encyclopedia.

Recovery Position

The recovery position or semi-prone position is a technique recommended for assisting people who are unconscious or semi-conscious and are able to breath on their own. It is also known as semi-supine laying position.

Two main risk factors are present when an unconscious or semi-conscious person is lying facing upwards. It can lead to suffocation of the person.

• The person's tongue can fall backwards and obstructs the airway due to loss of muscular control.
• Fluids like blood, vomit or saliva can collect at the back of the person's throat thereby creating the possibility of drowning the person.

When a person is lying face up, the esophagus (gullet) tilts down slightly from the stomach towards the throat. This, combined with loss of muscular control, can lead to the stomach contents flowing into the throat. This is known as passive regurgitation.

As well as obstructing the airway, fluid which collects in the back of the throat can also flow down into the lungs via the trachea (windpipe). Stomach acid will then be able to attack the inner lining of the lungs and cause a condition known as aspiration pneumonia (AP).

***AP develops due to the entrance of foreign material (including food, saliva or nasal secretions) that enters the bronchii. Depending on the acidity of the foreign material, a chemical reaction can occur and presence of bacteria may add to the inflammation***

The main purpose of teaching recovery position in lifesaving is such that the victim can lie down comfortably and breath on their own while the rescuer can maintain a watchful eye for any changes that is shown by the victim.

A good recovery position in my opinion comprises of:

• Ensure victim's airway is open at all times (head-tilt-chin-lift position)
• Ensure victim's mouth is downwards (facilitate in draining of blood and saliva)
• Ensure chest and stomach does not lay flat on the ground surface (easier to breath)
  
• Ensure victim's arm and knee are locked to maintain stability
  
• Rescuer is able to maintain visual contact of the victim while checking for signs of circulation every 5 min

In the recovery position, the law of gravity will keep the tongue from obstructing the airway as well as enables the draining of fluid from the mouth such that the victim will not choke on their own vomit or saliva.

For pregnant victims, they should always rest on her left side as lying on her right side may cause the uterus to compress the Inferior Vena Cava thereby making death a possibility!

For victims with torso wounds, it is recommended to place the wounds closest to the ground to minimize the possibility of blood going into the lungs causing a condition known as asphyxiation.

***Asphyxia is a condition of severely deficient supply of oxygen to the body***