Chapter 5 - Diving Related Disorders Flashcards
What are the different types of tissue?
Blood Nerves Organs Muscles Bone Cartilage Fat
What are fast tissues?
Blood and tissues with good blood supply because they absorb and release nitrogen quickly
What are slow tissues?
Fat, cartilage and bone that take longer to absorb and release nitrogen
What is the absorption and release of nitrogen known as?
On gassing - absorb
Off gassing - release
What are the symptoms of DCI?
Dizzy Loss of balance and coordination Rashes and itches Joint aches Collapse Loss of sensation and motor control
When do DCI symptoms mostly occur?
After the diver has surfaced - less than an hour (50%) within 6 hours (90%)
What are the two principal components to the descriptive term used?
Evolution - progression of the illness
Manifestation - the signs and symptoms noted
Acute (evolution) (manifestation) decompression illness
What is progressive evolution?
The severity of the signs and symptoms is increasing
What is static evolution?
Neither the number or severity of the signs and symptoms increases
What is spontaneously improving evolution?
Certain signs and symptoms may improve without recompression treatment
What is relapsing evolution?
Cases where they spontaneously improved may undergo a secondary deterioration
What is pain only manifestations?
Limb pain - joints most common
Girdle pain - poorly localised aching or constricting feeling in the abdomen, pelvis or chest
What is a neurological manifestation?
Loss of memory, seizures, loss of coordination and balance, loss of strength and loss of sensation etc
What is nystagmus?
The rapid uncontrolled movement of the eyes, the pupils appear to tremble and wobble
What is the neurological manifestation of the spinal cord?
Pins and needles
Numbness
Muscular weakness
Paraplegia - paralysis
What is an audio vestibular manifestation?
Barotrauma and tissue injury may be involved
Symptoms are... Vertigo Tinnitus Nystagmus Hearing loss Loss of balance Severe nausea
What is a pulmonary manifestation?
May be caused by nitrogen bubbles released into the blood or by lung over pressurisation
What is a cutaneous manifestation?
Severe itching around the shoulders that develops into a rash then mottling or marbling of the skin
What is a lymphatic manifestation?
Lymph nodes may become enlarged and tender - may be associated with oedema (excess fluid in body tissues)
The skin feels thick and may have a the pitted appearance of orange peel
What is a constitutional manifestation?
Non specific signs and symptoms that occur after diving eg. Headache Fatigue Malaise Anorexia (loss of appetite)
How many types of pulmonary decompression illness are there?
4
What is pulmonary DCI - Venous gas embolism?
Micro bubbles are formed in the venous system. Under a controlled ascent they are trapped in the lung fields and dissolve.
When the ascent isn’t controlled, masses of bubbles may be formed causing cardio-pulmonary consequences
What are the symptoms of Venous gas embolism?
Chest pain Cough Haemoptysis Shortness of breath Cyanosis Shock
What is pulmonary DCI air embolism?
Caused by excess pressure. It allows air to leak through the alveolar wall into the blood stream. The air bubbles can be lodged anywhere within the human body.
What are some of the signs and symptoms of air embolism?
Giddiness Numbness Paralysis Visual disturbances Respiratory problems Heart failure Death
What is pulmonary DCI pneumothorax?
Caused by air escaping the alveoli and getting trapped in the pleural cavity cause a collapsed lung.
What is the most serious form of pneumothorax?
Tension pneumothorax where the size of the collapsed lung increases in size with each breath.
What are the signs and symptoms of pneumothorax?
Pain on respiration Shortness of breath Cyanosis Displacement of the trachea Frothy blood from mouth or nose
What is pulmonary DCI emphysema?
Air migrates to other parts of the body. In diving it usually moves towards the chest and neck area
What are the three different types of emphysema?
Mediastinal - air trapped in the chest
Subcutaneous - air trapped below the skin
Interstitial - air trapped in and around tissues
What are the signs and symptoms of emphysema?
Difficulty swallowing
Difficulty breathing
A swollen neck
A change in voice tone
What is the first aid for DCI?
- Diver kept still - lying down and warm
- Fluids administered at a rate of >1 litre per hour
- 100% oxygen
- Primary assessment conducted
- Immediate transportation to a recompression chamber
Which factors may increase DCI?
Obesity Hard work Dehydration Alcohol Cold Being female Increase in age Infection Drugs Previous DCI Patent Foramen Ovale - atrial septal defect Lack of fitness Sawtooth profile dives - ups and downs
What is hyperventilation?
When you take a series of long deep breaths to get more time on a snorkel dive underwater
What does hyperventilation do?
Delays the urge to breathe by lowering the levels of carbon dioxide in your body which is dangerous
What are the effects of taking deep breaths before snorkel diving?
It takes longer before any stimulus to breathe is triggered
Oxygen is required but not replenished
Oxygen levels fall
Unconsciousness quickly follows
What is anoxia?
No oxygen and would cause death
What is hypoxia?
A partial lack of oxygen
What are the causes of hypoxia?
A gas mixture with a bad percentage of oxygen
Obstruction in the respiratory tract - asphyxia
Diseased or damaged lungs
Blood defect such as anaemia
General lack of blood
Carbon monoxide
What are the causes of hypoxia specific to divers?
Incorrect gas mixture Running out of air Equipment malfunction Contamination Restriction in the bloods ability to transport oxygen - DCI embolism
What are he signs and symptoms of hypoxia?
Cyanosis
Become less and less pink in colouration - blue colour develops at the nail beds, ear lobes and lips
What is the first aid for hypoxia?
Removal from immediate danger
Alert EMS
CPR if required
Administer oxygen
What are the causes of asphyxia?
Lack of oxygen Drowning Airway obstruction Poisoning Disease Electric shock
What are the signs and symptoms of asphyxia?
Shortness of breath Dizziness Rapid pulse Swelling of veins Cyanosis Unconsciousness
What is the first aid for asphyxia?
Remove from source
Alert EMS
CPR if required
Oxygen administration
What is pulmonary oedema?
Fluid in the lungs
What are the causes of pulmonary oedema?
High blood pressure
Water in the lungs from drowning
Heart failure
What are the signs and symptoms of pulmonary oedema?
Shortness of breath Dizziness Cyanosis Weak pulse Unconsciousness
What is the first aid for pulmonary oedema?
Treat as for asphyxia
What is exhaustion?
When the body is mentally or physically incapable of meeting the demands placed on it
What are the causes of exhaustion?
Over exertion
Stress
What are the signs and symptoms of exhaustion?
Breathlessness Anxiety Erratic pulse Muscular complaints Skin might take on bright red appearance
What is the first aid for exhaustion?
Stop activity
Hold on to a stable object
Stabilise breathing pattern - control/extend the exhalations
Change work or abort dive
What is hypothermia?
Caused when heat loss is greater than the heat production. Defined as a 2° loss of core body temperature
How much quicker does water conduct heat away from the body than air?
25x faster
At what sea temperature is the body incapable of maintaining the core body temperature?
23°
What are the causes of hypothermia?
Exposure to wind chill
Immersion in cold water without sufficient thermal protection
Exposure to cold air temperatures
What are the signs and symptoms of hypothermia?
Shivering at first Skin cold, dry and pale Disorientation and apathy Irrational behaviour Lethargy Unconsciousness Pulse slows and weakens Finally cardiac arrest
What is the first Aid of hypothermia?
Remove from cause
Primary assessment
Remove all wet clothing
Wrap the patient in anti hypothermia blanket
Monitor patients vital signs and symptoms
Always be gentle
What is hyperthermia?
When the temperature of the body rises. First the capillaries dilate and try to lose heat through radiation and then the sweat glands begin to produce more sweat and finally an increase in breathing rate.
What are the two types of hyperthermia?
Heat exhaustion and heat stroke
What are the causes of heat exhaustion?
A loss of salt and water from the body
What are the signs and symptoms of heat exhaustion?
Exhausted but restless Headache Tired Dizzy Nausea Muscular cramps Pale cold and clammy skin Rapid and weak pulse Breathing fast and shallow Casualty may faint if moved suddenly
What is the first aid for heat exhaustion?
Cool place
Sips of cold water
Add salt if they have been sweating
Primary assessment if they fall unconscious
What is the causes of heat stroke?
Feverish illness
High humidity or temperature
What are the signs and symptoms of a heat stroke?
Headache Dizzy Feeling of being hot Restlessness Flushed appearance Dry skin Full and bounding pulse
What is the first aid for a heat stroke?
Same as heat exhaustion as well as a cold wet sheet being placed over the victim
What are the causes of vomiting under water?
Seasickness
Dysbaric vertigo
DCI
Consumption of too much food or fluids
What are the signs and symptoms of vomiting underwater?
A feeling of nausea
What is the first aid of vomiting underwater?
Breathe with great control to prevent panic
Use the purge button and aim the stream of air towards the lips whilst vomiting
This will blow away the vomitus
When vomiting has ceased the diver will automatically take in a big gulp of air. If the free flowing air is pointed over the lips they should breath in air rather than water
What should you do when the person has finished vomiting underwater?
Achieve positive buoyancy
Remove breathing apparatus
Ensure airway is clear
Remove from water and conduct primary assessment
Administer oxygen and or take to the nearest recompression chamber
What are the causes of drowning?
Caused by the inhalation of liquid.
Causes a blockage of the airways
Leads cells to become hypoxic and then eventually anoxic
How are liquids, food and drink distinguished?
By the pharynx which directs liquids and foods down the oesophagus and air down the trachea.
What do you do if food or liquid accidentally enters the trachea?
Cough to remove them. This is caused by the laryngeal spasm. This helps to push the obstruction back up.
What is the difference between wet and dry drowning?
In 20-25% of casualties the laryngeal spasm is so powerful that little or no fluid enters the lungs
In 75-80% of casualties water is found in the lungs - wet drowning
How long should a nearly drowned patient be observed?
3 days
What is secondary drownif?
When after successful resuscitation the lungs may start to fill with fluid again - should be treated in hospital immediately
What are the causes of underwater blast injuries?
Explosions underwater represent a serious risk to divers due to the shock wave and noise of detonation.
What happens when there is an explosion underwater?
Explosion produces bubbles of gas which rapidly expands and collapses due to temperature and pressure. This means there are a number of repeated blows which become progressively weaker over time.
Why do divers need to be out of the water if explosives are being used?
Pressure waves are transmitted over a greater distance and with potentially lethal intensity. Pressure waves near the seabed can inflict more damage. The extent of the damage will be influenced by the initial charge, depth and distance from the diver
What are the signs and symptoms of underwater blast injuries?
The pressure waves pass through the body so the areas of most damage are lungs, sinuses, ear cavities and the abdomen. A shredding effect can take place and tissues can end up torn apart
What is the first aid for underwater blast injuries?
Admitted to hospital - May have internal injuries
