Triage
Triage (pronounced 'tree-ahz') is a French word used in the first aid and medical contexts to indicate the sorting and classification of casualties and the establishment of treatment priorities. It usually refers to a mass casualty situation, such as an earthquake or bus accident.
Even though triage generally applies to large numbers of casualties, it is also relevant to other first aid situations involving two or more casualties. There are times when members of the public, trained in first aid, make decisions on the treatment and care of casualties normally the responsibility of ambulance officers or a doctor. This is especially relevant in country areas where medical aid may be hours away.
A common example is when a member of the public travelling a remote country road comes across a motor vehicle accident involving several casualties.
Unfortunately, to effectively provide the best treatment for the most in need, some seriously injured casualties may have to be temporarily ignored. The requirement is for your limited first aid resources to be allocated to the casualties who will survive because of it and not to those who are likely to die.
To triage an incident, your approach has to be objective. To assume the responsibility for these decisions is an unenviable position to be in. You should ask yourself three questions:
- Who needs immediate treatment to save their life?
- Who will really benefit and who won't?
- If I treat one person, will others suffer seriously from lack of attention?
Safety, airway, breathing, circulation, control of severe bleeding, shock and burns are still the priorities when attending multiple casualties with little or no assistance.
Casualties in cardiac arrest are only given CPR if there are no other seriously injured casualties requiring life-saving treatment. If you become distracted with a casualty in cardiac arrest, you will be fully committed performing CPR (usually to no avail), at the expense of another who may be saved by your active intervention.
An unconscious casualty on their back, a person with severe bleeding, a casualty with a head injury going into shock - all are high priorities because without your intervention they may die. A conscious casualty with a fractured leg is less urgent and can wait until the more serious casualties are dealt with. A conscious casualty walking around, complaining of a sore shoulder, for example, is at the bottom of the triage list.
The most knowledgeable or experienced person present should undertake triage.
Oxygen administration
Oxygen is a colourless, odourless, tasteless gas essential for the body to function properly and survive. The air we breathe contains approximately 21% oxygen and the heart relies on oxygen to pump blood.
If not enough oxygen is circulating in the blood, it's difficult for the tissues of the heart to keep pumping. Supplemental oxygen is used to treat medical conditions in which the tissues of the body do not have enough oxygen.
Oxygen is a gas, but when administered as a supplement to normal atmospheric air, may also be considered a medication (or drug) in the way it is delivered.
The respiratory system
The anatomical features of the respiratory system involve those structures of the body that conduct air from outside the body to the lungs and those elements that control and facilitate the process.
The central nervous system (CNS)
The brain and the spinal cord make up the CNS and are the controlling mechanism.
The upper airway
The upper airway consists of those spaces and structures that assist and guide the movement of air from the nose and mouth to the 'wind pipe'.
Nasopharynx
Is the space behind the nose and extends over the roof of the mouth. It is into this cavity air is initially drawn when a breath is taken and dry air is warmed and moistened prior to its journey to the lungs.
Oropharynx
Is the cavity that extends from the nasal cavity to the hyoid bone above the opening to the 'wind pipe'? This cavity contains the tonsils.
Laryngopharynx
Is the space immediately above the larynx. The Laryngopharynx includes the glottis, the opening between the larynx and the vocal cords.
Larynx
Also known as the 'Adam's apple', is the cartilaginous structure located above the entry to the lower airway and close to the oesophagus, the entry to the stomach.
Lower airway
Trachea
Is a thin-walled tube approximately the same diameter as a garden hose. The trachea extends to the bronchial tree where the airway branches to the lungs.
Bronchi and bronchioles
The trachea branches into the left and right main bronchi, which successively branch into smaller bronchi, much like the structure of the branches of a tree. These smaller bronchi are located within the lobes of the lungs.
Lungs
The two lungs develop at the end of the bronchi and are contained within a cavity in the chest. The lungs are porous elastic organs that appear similar to a sponge.
Lobes
Each lung is composed of compartments called lobes; the right lung with three lobes, the left, two.
Alveoli
In the extremities of the lobes, groups of respiratory bronchioles terminate in clusters of structures called alveoli. The alveoli are small sacs composed of elastic tissue, covered by a thin membrane. It is through this membrane that gas exchange takes place.
Associated muscles
Diaphragm
A long, flat, smooth muscle attached to the lower six ribs, the sternum and the spine. When relaxed it is convex in shape, forming a 'dome' beneath the lungs. When the CNS stimulates the need for inhalation, the diaphragm flattens, enlarging the chest cavity and allowing expansion of the lungs.
Intercostal muscles
The intercostal muscles are the small smooth muscles between the ribs. When contracted, these muscles expand the chest cavity in an outward direction, providing an enlargement of the chest cavity.
Associated blood structures
Red blood cells
Red blood cells, or erythrocytes, are the most numerous and specialised cells in the body.
Erythrocytes
Erythrocytes are flexible concave microscopic discs, adapted to produce haemoglobin. Erythrocytes circulate through the lungs in the alveolar capillaries, collecting oxygen diffused through the membranes of the alveoli.
Haemoglobin
Haemoglobin is a hormone which attracts and binds oxygen and, to a lesser extent, carbon dioxide. It has a red pigment which gives blood its red colour. When oxygen combines with haemoglobin, it is known as oxyhaemoglobin and the enriched blood is a bright red colour. As carbon dioxide does not combine with haemoglobin as effectively, the resultant colour of the blood is dark red.
Respiration
The physiology (or function) of respiration involves all those anatomical features discussed previously. Respiration can be considered to start with the process of inhalation or 'breathing in'. At the start of each breath, our CNS is stimulated to direct the muscular diaphragm below the lungs to contract, as it contracts, or 'flattens', the chest cavity is enlarged. Because at this point the lungs are deflated, the pressure in them is low. As the air outside our body is at atmospheric pressure (14.7 psi or 100 kPa), it spontaneously moves into the lungs through the oropharynx to 'even up the pressure'.
The inhaled air moves through the upper and lower airways to the membranes of the lungs, into the alveoli. At this point, the oxygen content of the air is selectively moved through the walls of the alveoli.
Respiration occurs regularly, depending on the body's demands. An adult awake and at rest will generally have a respiratory rate of 14-18 breaths per minute. When the body is under stress, either physical or emotional, the rate rises accordingly and could be as high as 30 per minute. When deeply asleep, with the body completely at rest, the body's respiratory rate is around 7-8 breath's per minute.