A common situation is that you are about to dive, approach the water, bend down to put on your fins, and suddenly you feel pain in the eyebrow area. If you do not pay attention to this, your pain may increase and cause you a lot of trouble when trying to dive into the depths. To understand this problem, we asked questions about this phenomenon to Candidate of Medical Sciences Irina Skidanova, head of the department of otorhinolaryngology, who is also a CMAS diver **.

When engaging in scuba diving - be it diving or freediving - it is important to remember the medical aspects of deep diving. Pressure changes during descent and ascent can cause damage to organs or tissues - barotrauma. This applies to cavities filled with gases, the volume of which is limited by the bone skeleton - the paranasal sinuses (barosinusitis).
There are two types of barotrauma: compression and reverse compression. During a dive, the air in the paranasal sinuses will compress, and upon ascent, it will expand in accordance with Boyle's law. On the surface we do not feel the slow equalization of pressure. And a rapid increase or decrease in hydrostatic pressure is accompanied by a change in the volume of air in these cavities, which can lead to pathological changes in the mucous membrane. Barotrauma is possible even for experienced divers, since every dive there is a change in hydrostatic pressure. If you ignore a slight runny nose, you increase the risk of barotrauma. Beginners often make the mistake of thinking that since we breathe underwater through our mouths, nasal breathing is not important. It is also necessary to take into account the fact that in healthy people, cold water can cause reflex swelling of the nasal mucosa, blocking the sinus anastomosis, increasing the risk of developing barotrauma. Therefore, dive slowly, controlling your sensations. If you have a history of ear or sinus pain at depth, consult an ENT doctor before your next dive.

What causes headaches when diving?

The cause of a sharp headache when diving to depth may be barotrauma of the paranasal sinuses. This is due to the pressure difference in the bone cavities, which are unable to stretch and contract. The reason for the violation of pressure equalization in the sinuses is the disruption of the normal functioning of their natural openings (ostia), which open into the nasal cavity. Anatomical features or inflammatory phenomena in the nasal cavity and paranasal sinuses contribute to the blockage of these openings. Air cannot enter the sinus, and a vacuum is created. Barotrauma of the paranasal sinuses is caused precisely by the pressure difference in closed cavities, increasing swelling of the mucous membrane, which puts pressure on the nerve endings, causing pain. By the location of the pain, you can tell exactly which sinus is affected. If there is no clear localization of the headache, it is necessary to measure blood pressure (BP). In case of high blood pressure, it is necessary to take appropriate medications, and only after normalization of blood pressure should the condition of the ENT organs be assessed. If the headache has stopped, most likely your sinuses are fine. In addition, when blood pressure increases, headaches occur more often on the surface. If you suffer from hypertension, your blood pressure should be monitored before and after diving to avoid causing problems at depth, such as nosebleeds.

What are the paranasal sinuses and where are they located?

The paranasal sinuses are cavities inside the facial part of the skull that open into the nasal cavity through small openings (ostiae). The inside of the nose is divided into two halves by the nasal septum; they are connected to the external environment through the nostrils, and to the nasopharynx through the nasal openings (choanae). In each half of the nose, there are three ridges on the side wall - the turbinates (superior, middle and lower), which form three nasal passages (superior, middle and lower). The anastomoses of the paranasal sinuses open into the middle and upper nasal passages. The two maxillary sinuses (maxillary sinuses) are the largest sinuses that are located in the body of the upper jaw; the projection of the sinuses is located on the sides of the wings of the nose. The two frontal sinuses are located above the bridge of the nose between the superciliary arches in the thickness of the frontal bone, they have varying degrees of air communication - the worse, the more difficult the pressure drop is tolerable. Cells of the ethmoid labyrinth are cells of the ethmoid bone located between the eye sockets at the level of the base of the nose. The sphenoid sinus, located in the body of the sphenoid bone, is divided into two halves by a septum.

What diseases of the upper respiratory tract are a contraindication to diving?

Contraindications to diving from the ENT organs are relative, since they can be eliminated by conservative or surgical treatment.
These are: acute and chronic rhinitis; acute and chronic sinusitis; malignant and benign formations of the paranasal sinuses; deviated nasal septum.
After the end of acute diseases of the upper respiratory tract, it is better to avoid diving for several days until nasal breathing and the body’s defenses are completely restored. After all, not only difficult nasal breathing is fraught with danger. Weakened immunity against the background of hypothermia in water can complicate even a mild acute respiratory infection. To make a decision whether to dive or not, you must base your health on the severity of your infection. Of course, immediately after surgical treatment of diseases of the nose and paranasal sinuses, you should not dive. Recovery after surgery in the nasal cavity and sinuses takes place within one month. And even after this period, you need to be careful when diving for the first time. The speed of descent and ascent should be minimal so that there is time to evaluate your sensations.

What happens in the sinuses at depth?

When diving to depth, air under pressure and low humidity begins to act on the mucous membrane of the nose and paranasal sinuses. This leads to response changes in the mucous membrane of the paranasal sinuses. If the area of ​​natural anastomosis is blocked, the pressure difference provokes swelling and infiltration of the nasal mucosa and paranasal sinuses, and with a further increase in pressure, a submucosal hematoma is formed.

How can one suspect that barotrauma of the paranasal sinuses has occurred?

In this case, when diving to depth, pain sharply appears in the paranasal sinuses, which is often so severe that it forces the diver to immediately surface. After ascent, the pain decreases if you managed to react quickly and the depth was shallow. Sometimes pain can also appear during ascent.

What are the symptoms of paranasal sinus barotrauma?

This is a sharp headache that can be compared in strength to a toothache. The localization of pain varies depending on the affected sinuses - the bridge of the nose, cheekbones, upper teeth, forehead. Occurs during diving or ascent and persists on the surface. Often barosinusitis is combined with barootitis, which is manifested by congestion, pain and noise in the ears. Other symptoms are variable - nasal congestion, mucous discharge from the nose, and nosebleeds are possible. Neurological symptoms may be associated with damage to the adjacent trigeminal nerve and infraorbital nerve.

What are the degrees of barotrauma and what is affected?

Depending on the severity of symptoms, three classes of severity of barotrauma are distinguished (V. Vaisman). 1st class. Just discomfort in the sinus area (not accompanied by changes on the x-ray) of the paranasal sinuses. 2nd grade. Severe headache lasting up to 24 hours (with thickening of the mucous membrane of the paranasal sinuses on x-ray). 3rd grade. Severe headache lasting more than 24 hours (with pronounced swelling in the paranasal sinuses on x-ray) and nosebleeds. In most cases of barotrauma, the frontal sinuses are affected, which is associated with the anatomically narrow nasofrontal canal, even in healthy people. Barotrauma of the maxillary, ethmoid and sphenoid sinuses is less common and in most cases is associated with acute respiratory infection. The magnitude of the pressure drop required for barotrauma is individual and depends on the size of the natural sinus anastomosis and the rate of immersion.

What to do if you have barotrauma of the paranasal sinuses?

If a headache occurs, it is necessary to make a controlled ascent. First aid is vasoconstrictor nasal drops - Nazivin, Xymelin, which should be in every diver's first aid kit. They will help restore nasal breathing and open the natural anastomosis of the paranasal sinuses, thereby ensuring equalization of pressure with environment. The use of antihistamines (Zyrtec, Erius, Cetrin, etc.) will reduce the developed swelling in the paranasal sinuses, and therefore reduce pain. The use of non-steroidal anti-inflammatory drugs (nurofen, pentalgin) is also justified, since the effect of the drugs can reduce inflammation and relieve pain. Naturally, upon return, it is necessary to take an x-ray of the paranasal sinuses and see an ENT doctor. For persistent pain and persistent swelling in the sinuses (an x-ray will show this), infusion decongestant therapy is indicated, for example, with calcium chloride and dexamethasone.

In what cases is it necessary to take an x-ray of the paranasal sinuses?

The indications are as follows. Before diving: acute inflammatory phenomena in the nasal cavity, accompanied by nasal congestion, mucous or purulent nasal discharge. After diving: severe headache that occurs when diving under water. Indications for CT scan of the paranasal sinuses are chronic processes in the nasal cavity and paranasal sinuses. This is necessary to prevent the occurrence of barotrauma.

How to avoid barotrauma of the paranasal sinuses?

Never dive if you can't breathe through your nose. This applies to both acute rhinitis and sinusitis of an infectious nature, and chronic pathology in which nasal breathing is blocked (polyps, benign and malignant neoplasms). A deviated septum is not a contraindication to diving if the degree of deviation does not affect nasal breathing and the ability to blow through the nose and does not block the natural openings of the sinuses. Sinus cysts are detrimental to diving because pressure changes can trigger or worsen pain. Therefore, before deep-sea diving, it is better to be examined by an ENT doctor and remove all possible factors that provoke barotrauma.

Is it possible to dive if there is a residual runny nose after a respiratory infection?

Many believe that immersion for residual acute rhinitis and sinusitis is possible with the use of vasoconstrictor drops. Indeed, these drugs make nasal breathing easier, but their duration of action is limited. If you plan to stay underwater for a long time, more than 1.5–2 hours, the effect of the drops upon ascent will decrease, increasing the risk of damage to the sinuses and middle ear. Exercise self-control before diving, since YOU make the decision to dive yourself!

To reduce the risk of developing barotrauma, you need to choose the optimal dive speed that does not affect your well-being and allows you to have time to ventilate. And most importantly, do not dive if you have problems with nasal breathing!


Text: Irina Skidanova – head of the department of otorhinolaryngology, CMAS diver Photo: Vladimir Gudzev

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Surface ships and submarines built for the Russian Navy during the late USSR can be criticized
to blame for the imbalance in the composition of weapons, the inability to use them at full range, the lack
combat information and control system like "Aegis" - for anything other than aesthetic imperfection.
Graceful predatory silhouettes of cruisers, BODs, destroyers, multi-purpose nuclear submarines, which we inherited from the Soviet
shipbuilding school, continue to please the eye and cause pride among Russian citizens and respect in half
with the envy of citizens of foreign countries (destroyers, unfortunately, only please the eye).

Judging by the designs of ships of the latest (fourth) generation, developed at the Northern Design Bureau and the Almaz Central Marine Design Bureau (22350 and 20380),
naval architecture continues to receive due attention and, despite the new requirements that run counter to aesthetics,
In addition to the radar signature of the NK, the frigates and corvettes under construction are just as pleasing to the eye as their predecessors. However,
a reverent attitude towards the long-standing traditions and canons of the genre, unfortunately, is not universal. To date
There have already been two alarm calls causing concern about the new look of the Russian Navy.

1. The bow wall of the APKR (SSBN) project 955 "Borey" wheelhouse fence inclined forward

The fencing of the APKR cabin, pr. 955 (slightly retouched photo from newsreaders.ru from skroznik, submitted by tsonyo from forums.airbase.ru)

They prefer not to mention this architectural absurdity in descriptions of the Boreev design, but questions arise among
many and sometimes they are even asked to the authors of the project. Quote : "(correspondent of the Central Naval Portal Dmitry
Glukhov) - Why is the bow part of the wheelhouse (more precisely, the fencing of the retractable devices) of the SSBN project "Borey" made so poorly?
Usually - with a negative angle of inclination? (former general director of the Rubin Central Design Bureau Andrei Dyachkov) - This was done because of the peculiarities
placement in this place of one of the stations of the boat's hydroacoustic complex" (link).

That is, earlier, throughout the entire design and construction of nuclear submarines here and abroad, there were no such features,
but, having suddenly arisen, they turned out to be so significant for the combat effectiveness of a strategic submarine cruise
ra that for this it was necessary to disfigure its silhouette (it is very difficult to imagine a car with a windshield
would be tilted outward or a dolphin with its forehead tilted forward). Doubts about the appropriateness of this constructive
solutions arise also because in A. Dyachkov’s commentary we are talking, of course, not about the main one, but about the auxiliary (secondary)
power) station GAK, presumably - mine detection (opinionCurious c forums.airbase.ru).


The point here is most likely something else. Central Design Bureau "Rubin" has never attached much importance to the form of fencing for the cuttings of its projects -
they were always either strictly rectangular (family 667, 877, 677) or almost (949/949A). Obviously, tired of this one-
image, the management of the bureau decided to go down in shipbuilding history with "new cabin concept " (phrase from Acoustic with
forums.airbase.ru). Unfortunately, the military reception, the navy's commander-in-chief and the state leadership did not have enough taste,
to hinder the architectural research of "Rubin" and order it to be done as it should be, that is, beautifully. Make it beautiful without
Damage to the performance of individual products is always possible - if there is a desire (I know from experience).

In fairness, it should be noted that in some photographs where APKR are captured from a three-quarters angle from the nose or
stern, the acquired ugliness is almost invisible, but the art of industrial design in particular consists in
his objects looked equally impressive from all sides.

2. Trimmed nasal end of the Mistral type DVKD


"Mistral" (photo from nemiga.info) -THIS is what will show off in our parade formation at Navy Day!

Any reasonable explanation as to why the tip of the Mistral's nose was neatly cut off like a piece
I couldn't find any sausages. The most incredible assumptions are put forward on the forums, such as reducing windage
(tiny bow and enormous freeboard! ) or redirection of incoming air flow in order to reduce
turbulence on the flight deck is a problem that for some reason the designers of all the others stubbornly did not want and do not want to notice
aircraft carriers on the globe.

Or maybe everything is much simpler, and the solution to cutting the stem of the DVKD lies in the banal savings of the contractor company
on metal and man-hours? Or in the reluctance (inability) of the designer to find another way to meet the requirements specified in the technical specifications
mass load and ensure normal alignment? After all, several tons of iron, removed with a slight movement of the hand (thought)
the very bow and the very top of the ship’s hull are capable of having a much greater influence on the position of its center of gravity than
several hundred tons, located amidships in the waterline area. Another option : a longer flight deck was not needed,
and it was not possible to make the body proportionally shorter (due to a cylindrical insert) (or simply did not want to)
I wanted to change the layout) - why bother with useless art, if you can ingeniously simply cut off the unnecessary.

In general, the cut-off Mistral fits well into the general picture of the degradation of European (if not world) aesthetics
naval architecture with its "Darings" and "Horizons". God bless them, it’s their choice, but why drag this decadence into
Russia? To be honest, right up until the launch of the Vladivostok, I childishly hoped that as part of the finalization of the project for
needs of the Russian Navy, the Russian "Mistral" will have a piece of its stem welded on so that it ("Mistral") is not too discordant
with the existing ship composition of the domestic fleet. It didn't come true. As in the case of the Boreys, the customer did not notice or
pretended not to notice the pronounced ugliness and did not insist on making changes to the project (the French were very
we need this order and they would probably try).

I would like to think that the unsightly "Boreas" and "Mistrals" are an unfortunate misunderstanding that will not happen again, and our military
ships were, are and will bethe most beautiful in the world .

Other photos of the new concept for the wheelhouse fencing of the Rubin Central Design Bureau

Looking at the ship in profile, you can appreciate its outlines and hull lines. The vessel itself consists of a frame, called a frame, and planking. The body kit serves to impart rigidity to the entire structure. It also shapes the appearance of the ship, its contours. You can notice that in the front (bow) part of the ship it has a special shape. The bow of the ship is specially made pointed so that when moving through the water, the ship experiences minimal resistance from the environment.

In nautical terminology, the front end of the ship is called the bow. In its location it is opposite to the stern. The bow of a ship most often has an elongated shape, narrowed from the sides. Its function is to cut waves that interfere fast movement vessel. This unique shape of the bow best suits the operating conditions of the ship.

Elements of the bow of the ship

The bow of the ship has a complex structure. It is designed to reduce resistance to a minimum water element. At the very end of the bow there is a stem. This is a thick beam, which is a kind of continuation of the keel. In the place where the stem approaches the waterline, a metal plate is often placed, which is called a “green” or “cutwater”.

In ancient times on the nose sailing ships Usually they placed decorations in the form of figures - rostras, which performed a decorative function. Such images made it possible not only to make the ship more attractive, but often gave warships an intimidating appearance. Roman warships, instead of decorative figures, often had massive rams at the front, which ended at the bow.

The deck elements of the front part of the ship also have their own names. Nasal space upper deck The ship is called "tank". On sailing ship the forecastle begins at the foremast and ends at the extreme forward end of the vessel. Sometimes a ship has an elevation on the deck in the front part - a forecastle. This structural element can occupy up to half the entire length of the vessel. Rigging and mooring equipment is installed on the forward part of the deck.

In the area of ​​the bow, the ship's hull has a reinforced structure. The set here is more durable and frequent, and the plating has significant thickness and strength. This is done so that the ship can confidently sail against the wind and strong waves. A strong bow is also needed when touching the pier during mooring. The bow, in any sailing conditions, takes on the main load of the external environment, so the requirements for its design are always more stringent.

When looking at an ocean-going vessel, it is not always possible to imagine how many parts it consists of. What first catches your eye is the external shape of the structure, the contours of the hull and the deck superstructures. Meanwhile, any ship is a complex system that includes a number of elements, each of which has its own purpose and name.

Main parts of the ship

The basis of any ship, be it a small vessel or a giant one ocean liner, is his body. It consists of a set that includes rigid longitudinal and transverse elements, as well as a skin that is attached to the set from the outside. The set in combination with the skin gives the vessel smooth outlines, guarantees water resistance and protection of the hull from damage. This is a kind of backbone, the skeleton of the ship.

Conventionally, the body can be divided into two parts. The front is called the bow, and the back is called the stern. The part of the ship that is below the waterline is called underwater. Everything that rises above the surface of the water is the surface part of the ship. The stern and bow on both sides of the center line are connected by sides.

The horizontal surface at the top of the hull is called the deck. It has long been assembled from boards tightly fitted to each other. One or more vertical masts are installed on the decks of sailing ships, to which sails and rigging equipment are attached.

Large ships are equipped with a superstructure in their upper part. This structure serves as a continuation of the sides and can occupy a significant part of the deck area. A massive superstructure allows efficient use of space on the deck, but impairs the stability of the ship and increases its windage. The control room, which is part of the superstructure, is used to control the ship.

Other ship design elements

In the middle and bow of the ship you can often see a continuation of the side, slightly rising above the surface of the deck. This lightweight structure made of wood or thick canvas is called a bulwark. It can be permanent or temporary. The bulwark is indispensable during heavy seas, when passing dangerous reefs and sailing.

They have their own names and elements of the vessel set. The main longitudinal part of the structure, which runs along the entire hull in its lower part, is called the keel. At the front, the keel becomes a sloping stem. The aft end of the keel is called the sternpost. The steering wheel is usually hung on it. A shaft can also be passed through the sternpost