Barotraumatism
A barotraumatism is a touching accident the fabrics of the Human body. It is caused by a change of Pression of the Gaz in the body.
Concretely, a barotraumatism occurs when there is a difficulty of adaptation between the Pression of Air inside a Cavité of the body and the external Pression. These variations of Pression can occur at the time of activities like the Plongée underwater, the diving in Apnée or at the time of voyages in Avion. The variation of the pressures is stated by the law of Boyle-Mariotte.
The damage is caused in the parts of the human body around the cavities because the Gaz are compressible with the increase in pressure (they decrease by volume) whereas the fabrics are not it.
The external increase in the pressures involves a reduction in the volume of the gas which attracts towards the center of the Cavité fabrics forming the envelope.
On the contrary, the external pressure decrease involves an increase in the volume of the gas which will have tendency to pushes back the fabrics (phenomenon of the balloon of goldbeater's skin).
General information
Causes
On the surface, the Pression is known as atmospheric (it is then in general of 1 bar).
To 10 Meter S of depth, this same Pression is of 2 bars. The pressure thus doubles in the zone ranging between the surface and 10 meters of depth. This important variation generates greater risks of barotraumatisms in this zone. Thereafter, the Pressure increasing by 1 bar by section of 10 meters, the difference is less felt.
Demonstration
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with the descent:
-
with the increase:
- let us fill this bag again, to 10 Mètre S of depth this time, with 5 Liter S of air. Once gone up on the surface, its volume will have doubled.
So instead of the plastic bag, the container is a Cavité Human body (Oreille S, sine, Poumon, Dent S for example), the fabrics papering it will be attracted towards the center to the tear at the time of the descent and will be distended until the bursting at the time of the increase.
Localization of the accidents
List various zones likely to be of the hearths of accidents of the barotraumatic type in diving:
- the Oreille S
- the sine (causing accident of the Sinusitis S or the barotraumatic otitises)
- the Poumon S (with pulmonary risk of overpressure)
- the eyes (the variations of pressures of the air contained in the mask can cause a Placage of mask)
- the Dent S can cause problems in the event of bad condition
- the Peau (the port of a combination seals can cause cutaneous accident)
Prevention
These accidents can be avoided by the application of simple precautions.
During the immersion, the plunger must go down gently, in order to leave time to the internal and external pressures to balance. In the event of impossibility (sine stopped for example), it is necessary to stop the descent and to cancel the diving until re-establishment of the possibilities of balancing.
At the time of the increase, it is necessary to take care to empty in a continuous way the cavities in question in order to avoid any risk of swelling, even of explosion.
Squeeze
The word squeeze indicates the phenomenon of reduction in the volumes of air in spaces close to the skin (mask, combination seals) as well as the Douleur and the disadvantages which it can induce.
Various barotraumatisms
The Ear S
The barotraumatism can indifferently touch only one or the two ears. In the case of an auricular barotraumatism, it is the tympanum, strongly requested during the variations of pressure which can ignite.
Causes
The causes of a barotraumatism of the Oreille can be:
- an obturation partial or total of one or both Eustachian tubes due to mucosities encumbering the nasal fossae;
- an obturation of the auditory canal by a stopper of Cerumen;
- a operation of balancing too strong or carried out too tardily.
The barotraumatism of the Ear, causing an ignition of the tympanum, can give place to a barotraumatic Otite (congestion of the tympanum). This otitis, if it is sufficiently serious, can involve a perforation of the tympanum.
A barotraumatism of the Oreille intern (due in general to a too brutal Operation of Valsalva) is a serious case because reaching the centers of the Audition and the balance. It requires a hospitalization without delay.
Alterno-baric giddiness
This phenomenon enough current is due to a lack of permeability of the one of both Eustachian tubes. In the event of problem of balancing on one of both Ear S, the difference in information transmitted to the Cerveau by the two bodies of the balance which are the Oreille S causes short a giddiness and a confusion.
In this case, the action to be taken consists in swallowing without never making Manœuvre of Valsalva.
Symptoms
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pain
- Giddiness and/or nauseas
- Acouphène S (buzz, whistles)
- bursting of the tympanum
Treatment
In all the cases, it is necessary to cease the descent immediately (or increase) and to be placed at the depth where the symptoms disappear.
Once increase carried out slowly, to cease the diving for at least 12 hours and to consult a doctor specialized if the pain persists.
NB: not to put auricular drops without medical regulation because a tear of the tympanum could involve a penetration of the liquid in the middle ear and an infection
Prevention
Not to plunge caught cold, to rinse the nasal fossae with sea water while launching itself.
To carry out the Operations of balancing in a systematic and frequent way and this, at the beginning of the immersion.
The sine
Causes
Sinusal secretions (or mucus), can sometimes seal partially or completely the channels of connection between the sine and the nasal fossae. If these channels are sealed, they prevent the unrestricted passage of the air and thus limit balancing between Pression intern and external Pression.
Symptoms
More or less acute pain according to the pressure exerted on the Mucous S sinusal.
Treatment
To stop the descent or the increase and to place themselves at the depth putting an end to the pain. To rinse the nasal fossae with sea water by removing the mask.
Attention , this operation can appear very dangerous and must be carried out with the assistance of sound Binôme.
Prevention
Not to plunge caught cold and to rinse the nasal fossae with sea water at the time of the setting to water.
The eyes
Causes
At the time of the descent, the interior volume of the mask decreases with the increase in the Pression. The supple skirt of the mask makes it possible to accompany this movement until its elastic limit. Once this one reached, volume cannot decrease any more and the depression created will cause a bursting of the capillary located around the ocular orbit by an effect of suction.
Symptoms
Sometimes an embarrassment, disorders of the Vision, a épistaxis, even a more or less sharp pain accompany this accident. Nevertheless, most of the time, there remains painless and the plunger realizes there at the end of the diving because of or the Hématome (S) ocular (S).
Treatment
The effects disappear from themselves enters 24 and 48 hours after the diving. In the event of pain, to use a Eye lotion Disinfectant.
Prevention
It is necessary, at the time of the descent, to blow by the nose of time to others, in order to add a little air in the mask, which will cause it to take off of the face.
The Tooth S
Causes
See also: Tooth (plunged)
In the event of crack on a Tooth and if the increase is not stopped, it can burst with a risk of syncope.
Symptoms
Very violent pain sometimes, feeling of Cold on the tooth.
Treatment
To stop the increase and to leave time to L surplus of air to escape from the cavity. It is sometimes necessary to go down again a little in order to relieve the pain.
Prevention
It is recommended to pass a dental visit every year by specifying to the expert his quality of plunger.
Internal S and the Stomach
Causes
Two cases of figure can arise for this accident:
- the Gases imprisoned in the cavities (Stomach or Intestin S can be subjected to the variations of pressure without being able to balance, causing a dilation of the body;
- at the time of very long divings (case of the professional or hard-working plungers underwater), the production of Gaz at the bottom during the Digestion can cause pain to the increase.
Symptoms
Pains more or less important being able to go, in very rare case, until the syncope, even the cardiac arrest (following the compression of the Heart by the Stomach).
Treatment
It is first of all necessary to stop the increase then to try to evacuate the gas surplus, which is far from being easy under water (!).
Prevention
To take care to have a Food low in Food S generators of Gas.
The Lung S
The accident barotraumatic in the pulmonary zone is called pulmonary overpressure . It is undoubtedly the most serious accident which one can meet in this activity and can be invalidating with life, even mortal. It is important to know that it is also the simplest accident has to avoid, because it is enough never not to block its breathing.
Attention: this accident, particularly dangerous requires only one weak variation of Depth. It can occur in 3 to 5 meters of water. Indeed at the time of an increase of 5 meters (1,5 bar) on the surface (1bar) the volume of air contained in our lungs will have increased by 50% (30% of 3 meters on the surface).
Causes
In the event of closing of the Glottis (fear panic, contact of water with the Larynx, etc) or of spasmodic contraction of this one, the air remains imprisoned in the Poumon S. At the time of the increase which follows (in general precipitated), pursuant to the Loi of Mariotte, the pressure decreases and, if the plunger blocks its breathing, the volume of air contained in the Poumon S increases. The lungs will dilate until the elastic limit of the air cells. When the elastic limit is exceeded, of the cells tear, the gaseous exchange cannot be carried out more correctly.
Vital oxygen any more or is not conveyed almost more by blood towards the cells of the organization.
This accident breaks up into two phases:
- mechanical phase
- distension of one or more cell (S) then bursting of this one
- compression of the cell S neighbors, from where a reduction in the ventilatory capacity and a Pneumothorax plain or bilateral
- tearing of two layers of the Plèvre with passage of air in the Médiastin which can precede a compression by a still healthy Lung and/or cardiac muscle
- passage of the air in the subcutaneous zone of the Neck causing a subcutaneous Emphysema.
-
neurological phase
Directed towards the Aorte they go, in the aortic stick, to pass in the Carotide S, vertically laid out then to find itself in the circuit of irrigation of the Cerveau. This one being in tree structure with increasingly small ramifications, the bubbles of air will end up being wedged (cerebral aéro-embolism), then preventing the Oxygène from passing and contributing to create a Nécrose cerebral nervous zones.
Other bubbles of air can pass in the Artère S coronary S and come to disturb the operation of the Cœur, depriving it of the contribution in vital Oxygène with its operation.
Symptoms
-
mechanical phase
-
neurological phase
- state of shock: Pulse fast, palenesses, or dyed purplished
- turbid of the Word and/or the Vision
- loss of sensitivity
- loss of motricity (generally in the form of Hémiplégie left, even right)
- ventilatory Stop and/or circulatory
- dead
Treatment
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put under Oxygénothérapie normobare in order to stage at the ventilatory distress
- immediately alert the qualified helps according to the zone or the country (Pompier S, CROSS-COUNTRY RACE, daN, life guard, etc)
- to evacuate towards worms a hospital medium without delay by applying the gestures of First aid which is essential (Cardiac massage, artificial Ventilation, etc)
- if the state of the victim allows it and that it is not allergic, to make him take Aspirine at a rate of 500 Mg for an Adult and the to hydrate.
Prevention
In order to prevent this type of accident, it is permanently necessary to make it possible the air to be evacuated while expiring with the increase. The hyperextension of the Cou is particularly effective in this case since it prohibits the closing of the Glotte. This instruction takes all its importance in the case of gone up not controlled (misuse of the waistcoat, Panique, Essoufflement) during which a little tested plunger will not inevitably think of expiring.
One should not either make Apnée in Plongée underwater out of bottle in order to avoid the risks of overpressure to the increase. Same manner, one should not give air on its Détendeur for a apneist or an underwater hunter, who will not be inevitably accustomed to expiring with the increase.
The Asthma nonallergic or the Bronche S to valves is counter-indications with the practice of the Plongée underwater in order to prevent the risks of pulmonary overpressure.
See too
Related articles
External bonds
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Encyclopedia of the urgency
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