How can divers identify potentially life-threatening conditions after a dive. What are the top signs of decompression sickness and other diving-related injuries. When should a diver seek immediate medical attention after experiencing post-dive symptoms.

Understanding Post-Dive Symptoms: When to Be Concerned

Scuba diving, while exhilarating, can sometimes lead to serious medical conditions if proper precautions are not taken. Recognizing the difference between normal post-dive discomfort and symptoms of potentially life-threatening conditions is crucial for every diver. This comprehensive guide will explore the top signs of serious diving injuries, helping divers make informed decisions about their health and safety.

Chest Pain: A Red Flag for Pulmonary Barotrauma

Chest discomfort after diving should never be ignored. Are you experiencing pain or discomfort when swallowing following a dive? This could be a sign of pulmonary barotrauma. Sharp pain localized to one side of the chest or a feeling of tightness may indicate a pneumothorax, commonly known as a collapsed lung.

Other symptoms associated with pulmonary barotrauma include:

• Shortness of breath
• Rapid heart rate
• Accelerated breathing
• Persistent cough
• Unusual fatigue
• Blueish skin tone (cyanosis)

If you experience any combination of these symptoms, it’s crucial to seek immediate medical attention. Pulmonary barotrauma can rapidly escalate into a life-threatening situation if left untreated.

Paralysis and Weakness: Potential Signs of Decompression Sickness

Paralysis or partial paralysis affecting any part of the body is a severe symptom that may indicate Type II Decompression Sickness (DCS). Additionally, weakness or paralysis in the extremities could be a sign of Arterial Gas Embolism (AGE), an extremely serious condition.

AGE symptoms may also include:

• Bloody froth from the mouth or nose
• Convulsions
• Loss of consciousness (most common sign)

Any suspicion of AGE warrants immediate evacuation to a medical facility equipped to handle diving-related emergencies. Time is of the essence in treating these conditions, and delays can result in permanent damage or even fatality.

Joint Pain: Not Just Muscle Soreness

While some muscle soreness is normal after diving, persistent joint pain should raise concerns. Are you experiencing steady or throbbing pain, particularly in larger joints like shoulders and elbows? This could be indicative of Type II DCS.

The pain may initially feel similar to a muscle sprain, but it’s essential to err on the side of caution. Any unusual joint discomfort following a dive should be evaluated by a qualified medical professional, preferably one with experience in diving medicine.

Differentiating Between Normal Soreness and DCS

Normal post-dive muscle soreness typically:

• Affects muscle groups rather than joints
• Improves with rest and gentle stretching
• Doesn’t worsen over time

In contrast, joint pain associated with DCS often:

• Focuses on specific joints
• May worsen with time or movement
• Can be accompanied by other symptoms like fatigue or skin changes

Skin Manifestations: More Than Just a Rash

Skin issues following a dive can be more than just a reaction to saltwater or sun exposure. A rash, itchy feeling, or skin marbling may indicate a type of Type I DCS known as a “skin bend.” While it might seem less severe than other symptoms, skin bends have been linked to more serious neurological DCS symptoms.

Characteristics of skin bends may include:

• Mottled or marbled appearance of the skin
• Intense itching
• Raised, red patches
• Sensation of skin burning or crawling

It’s crucial to treat any unusual skin changes after diving as seriously as other diving-related injuries. Early recognition and treatment can prevent the progression to more severe forms of DCS.

Vertigo: When the World Keeps Spinning

Vertigo is often misunderstood and confused with general dizziness. True vertigo creates a sensation that the world is spinning around you, even when you’re perfectly still. If you experience vertigo during or after a dive, it’s essential to assume it’s dive-related and respond accordingly.

Potential causes of dive-related vertigo include:

• Decompression sickness
• Impure breathing gas
• Imbalance in ear equalization

Persistent vertigo may indicate a more serious underlying condition and may require evaluation by an ENT (Ear, Nose, and Throat) specialist. Don’t hesitate to seek medical attention if vertigo persists or is accompanied by other symptoms.

Differentiating Vertigo from General Dizziness

Understanding the difference between vertigo and general dizziness can help divers communicate their symptoms more effectively to medical professionals:

• Vertigo: A sensation of spinning or the environment moving around you
• Dizziness: A feeling of lightheadedness, unsteadiness, or faintness

Both symptoms warrant attention, but vertigo is more likely to be associated with serious diving-related conditions.

Headaches: A Warning Sign of Multiple Conditions

Headaches after diving can be a symptom of various conditions, ranging from mild dehydration to severe neurological issues. It’s crucial to consider the context and accompanying symptoms when evaluating the seriousness of a post-dive headache.

A headache combined with the following symptoms may indicate dehydration or heat stroke:

• Hot, dry skin
• Amber-colored urine
• Difficulty urinating
• Nausea or vomiting
• Mental status changes
• Body temperature exceeding 104°F / 40°C

On the other hand, a headache accompanied by these symptoms could suggest Type II DCS:

• Muscle weakness
• Difficulty walking
• Confusion or cognitive impairment
• Vertigo or dizziness
• Impaired balance

In either case, immediate medical attention is necessary. Heat-related illnesses and DCS can both escalate rapidly if not treated promptly.

The Dangers of Symptom Denial: A Cautionary Tale

Experienced divers are often prone to downplaying or ignoring post-dive symptoms, attributing them to normal fatigue or minor discomfort. However, this approach can lead to severe consequences, as illustrated by the following case study:

A male diver in his sixties experienced weakness, dizziness, and confusion shortly after surfacing from a dive. Despite having completed four consecutive days of diving within his computer’s parameters, he initially dismissed these symptoms. After resting, the dizziness and confusion subsided, leading him to further ignore the warning signs.

The next day, the diver reported weakness and muscle spasms in his legs, along with difficulty urinating. This delay in seeking treatment resulted in the need for multiple recompression treatments and left the diver with some residual sensory deficits.

This case underscores the importance of taking all post-dive symptoms seriously, regardless of diving experience or adherence to dive tables. Early intervention with first aid oxygen and prompt medical evaluation could have potentially prevented the progression of symptoms and long-term consequences.

Lessons Learned from Delayed Treatment

• Never underestimate early symptoms, even if they seem mild
• Administer first aid oxygen at the first sign of potential DCS
• Seek professional medical evaluation for any unusual post-dive symptoms
• Remember that symptoms can worsen over time if left untreated

When in Doubt: The Importance of Seeking Professional Help

Given the potential severity of diving-related injuries, it’s always better to err on the side of caution. If you or a fellow diver experience any of the symptoms discussed, don’t hesitate to seek professional medical advice.

Resources available to divers include:

• DAN’s Medical Information Line: +1 919-684-2948 ext. 6222
• Local emergency services
• DAN’s Emergency Hotline (for urgent situations)

Remember, delay in seeking care is a common problem in the proper treatment of diving-related accidents. Early intervention can make a significant difference in the outcome of many diving injuries.

The Role of Dive Insurance in Emergency Situations

Many divers are unaware that standard medical insurance plans often do not cover the full scope of diving-related emergencies. For instance, while hyperbaric treatments might be covered, the cost of transportation to a hyperbaric chamber (which averaged US$20,000 for air ambulance services in 2016) may not be included.

Consider the following when evaluating your insurance coverage:

• Does your current plan cover diving-specific treatments?
• Are evacuation and transportation costs included?
• What is the coverage limit for diving-related emergencies?
• Are there any geographical restrictions on coverage?

Organizations like DAN offer specialized dive accident insurance that can provide crucial coverage in emergency situations. Investing in comprehensive dive insurance can provide peace of mind and potentially save significant out-of-pocket expenses in the event of a diving accident.

Preventive Measures: Minimizing the Risk of Diving Injuries

While recognizing and responding to symptoms is crucial, preventing diving injuries should be every diver’s primary goal. By following best practices and maintaining overall health, divers can significantly reduce their risk of experiencing serious diving-related conditions.

Pre-Dive Precautions

• Maintain physical fitness and overall health
• Stay well-hydrated before, during, and after diving
• Get adequate rest between dives and diving days
• Perform thorough equipment checks before each dive
• Plan conservative dive profiles, especially for multi-day diving

During the Dive

• Ascend slowly and perform safety stops
• Monitor dive computer and stay within no-decompression limits
• Avoid rapid changes in depth, especially near the end of the dive
• Practice proper buoyancy control to avoid rapid ascents
• Breathe normally and avoid holding your breath

Post-Dive Care

• Avoid flying or ascending to altitude for at least 24 hours after diving
• Stay hydrated and avoid alcohol consumption
• Monitor for any unusual symptoms in the hours and days following a dive
• Perform light exercise to promote circulation and off-gassing

By incorporating these practices into your diving routine, you can enhance your safety and reduce the likelihood of experiencing serious diving injuries. However, it’s important to remember that even with the best precautions, diving carries inherent risks, and being prepared to recognize and respond to potential injuries remains crucial.

Advancing Dive Safety: The Role of Education and Research

As our understanding of diving physiology and medicine continues to evolve, so too does our ability to prevent and treat diving-related injuries. Staying informed about the latest developments in dive safety can help divers make more informed decisions and potentially save lives.

Continuing Education for Divers

Diving safety doesn’t end with initial certification. Continuing education can help divers:

• Stay updated on the latest safety protocols and best practices
• Learn advanced techniques for dive planning and execution
• Understand the physiological impacts of diving more deeply
• Develop skills in emergency response and first aid

Consider taking advanced courses or attending diving seminars to expand your knowledge and skills. Many diving organizations offer specialized courses in areas like dive physiology, technical diving, and dive medicine that can enhance your understanding of diving risks and how to mitigate them.

The Importance of Dive Research

Ongoing research in dive medicine and physiology plays a crucial role in improving diver safety. Some areas of current research include:

• Long-term effects of repetitive diving
• Improvements in decompression algorithms
• Advanced treatments for decompression sickness
• Effects of diving on specific populations (e.g., older divers, those with pre-existing conditions)

Supporting and staying informed about this research can help divers make more informed decisions about their diving practices. Consider joining diving research initiatives or participating in studies when possible to contribute to the advancement of dive safety.

Technology in Dive Safety

Advancements in diving technology continue to enhance safety measures. Some recent developments include:

• More sophisticated dive computers with advanced algorithms
• Improved breathing gas analysis tools
• Enhanced communication systems for underwater use
• Wearable devices that monitor physiological parameters during dives

While these technological advancements can greatly improve safety, it’s important to remember that they are tools to aid in decision-making, not replacements for diver education and good judgment.

By staying informed, continuing to learn, and embracing new safety technologies, divers can significantly reduce their risk of experiencing serious diving injuries. However, the ability to recognize and respond to symptoms of diving injuries remains a critical skill for every diver, from novice to expert.

Top 6 Signs of a Serious Diving Injury

Diving is a physical activity so it’s not unusual for divers to experience muscle soreness or other post-dive discomfort. But sometime those aches and pains are signs of a serious medical problem. Recognizing the early signs of decompression sickness (DCS), heat stroke, and other conditions can help an injured diver get the medical attention they need.

Know the Signs

1. Chest Pain

Divers who experience chest pain or discomfort when swallowing after a dive may have pulmonary barotrauma. Sharp pain on one side of the chest or feeling tightness in the chest may be signs of a pneumothorax, also known as a collapsed lung. Other symptoms include: shortness of breath, rapid heart rate, rapid breathing, cough, fatigue and/or blueish skin.

2. Paralysis, Partial Paralysis or Weakness

Paralysis of one or more parts of the body may be a sign of Type II DCS. Weakness or paralysis in the extremities may also be a sign of arterial gas embolism (AGE). Other symptoms of AGE include bloody froth from the mouth or nose and convulsions, although the most common sign of an AGE is loss of consciousness. AGE is considered extremely serious and suspicion of AGE symptoms warrants immediate evacuation to medical care.

3. Joint Pain

Steady or throbbing pain particularly in larger joints such as the shoulders and elbows may be a ;sign of Type II DCS. The pain may feel like a muscle sprain, but it’s important to be proactive and have any symptoms evaluated by a qualified professional.

4. Skin Issues

A rash, itchy feeling, or skin marbling may be a sign of a type of Type I DCS known as a skin bend. This type of DCS has been linked to more serious neurological DCS symptoms, and should be treated as seriously as other diving related injuries.

5. Vertigo

Vertigo is often confused with dizziness, but true vertigo feels like the world is spinning. If vertigo occurs during or after a dive, assume the cause is related to the dive and respond accordingly. Vertigo can be caused by decompression sickness, impure breathing gas, or an imbalance in ear equalization. Persistent vertigo may be the sign of a more serious underlying condition, and evaluation by an ENT may be required.

6. Headache

A headache combined with hot, dry skin, amber-colored urine, or problems urinating are possible signs of dehydration and/or heat stroke. Other symptoms of heat stroke may include: a pronounced change in mental status, nausea or vomiting, loss of consciousness, cessation of sweating and/or a body temperature exceeding 104°F / 40°C. Read more about the symptoms and treatment of heat-related illnesses.

A headache along with other nervous system issues such as: muscle weakness, difficulty walking, confusion or impairment of cognitive functions, vertigo, dizziness and/or impaired balance may be signs of DCS II. Read more about the signs and symptoms of DCS and call EMS right away if you suspect a diver has DCS.

Case Summary:

What Happens When Symptoms Are Ignored

A male diver in his sixties felt weak, dizzy, and confused twenty minutes after surfacing from a dive. The man had been diving for four consecutive days, and the dives were uneventful and within the parameters of his computer. He returned to his room and, after resting, the dizziness and confusion resolved. The next day, he called DAN reporting weakness and muscle spasms in his legs and difficulty urinating.

This is an example of a diver underestimating his symptoms. The early post-dive onset of weakness, dizziness and confusion are some of the typical symptoms of DCS. First aid oxygen should have been administered from the onset of symptoms, not delayed until next day. This diver was fortunate his leg weakness did not progress to full paralysis. Several recompression treatments were needed before the diver regained full control of his bladder and strength of his legs, however, some loss of sensory functions remained.

When in Doubt, Call DAN

If you or another diver experience these symptoms, don’t hesitate to call DAN’s Medical Information Line (+1 919-684-2948 ext. 6222) to review your case with a medic. If you are experiencing an emergency call local emergency services first then call DAN’s Emergency Hotline. Delay in seeking care is a common problem in the proper treatment of diving-related accidents.

Be Prepared, Get Insured

Many medical insurance plans only cover the cost of hyperbaric treatments and not the cost of getting you to the chamber (average cost for an air ambulance in 2016 was US$20,000). Read questions every diver should ask their insurance provider and why every diver should consider DAN Dive Accident Insurance.

Join DAN

Symptoms Scuba Divers Should Never Ignore

Denial, the joke goes, is not just a river in Egypt. But sometimes it’s the most experienced divers who are the first to shrug off aches and pains as part of the dive life. Most of the time, that’s true. But sometimes it can lead to serious issues.

The problem, says Neal Pollock, Ph.D., former research director of Divers Alert Network, is that people have such faith in their computers and in their belief that if they do everything “right,” then nothing can go wrong. “The first rule of dive-related injury is it can happen to you, no matter how careful you are,” Pollock says. “You can minimize risk, but you can’t eliminate it. So it’s very important to, of course, dive conservatively, but also listen to your common sense and not brush off symptoms, because with many of these conditions, when you wait, things only get worse.”

Keep an eye out for these key symptoms after diving.

iStockphoto

That said, we all know that it’s common to feel a little “off” during a dive trip. We get headaches. We get nauseated. We get lightheaded. All pretty par for the course for a long day on the water. How’s a diver to know what’s serious and what’s standard fare? If you remember nothing else, remember this, says Pollock: “Any symptom that is unusual, new or intense deserves your attention.” So if you have a bum knee or chronic tennis elbow, it’s probably nothing if those joints flare up in a familiar way after a long day of diving. But if they hurt more than usual or they hurt in a new way, pay attention to it. If it continues nagging at you for more than 15 or 20 minutes, consider it a symptom to be checked out.

Likewise, if a symptom shows up very shortly after surfacing, it should raise suspicions, says Jake Freiberger, M.D., MPH, director of Duke Dive Medicine. “Research shows 50 percent of symptoms appear within 10 minutes of returning to one atmosphere, and only 15 percent of symptoms are delayed for more than one hour,” he says. Still not sure if those tingling fingertips are cause for concern? Here are seven symptoms you should never ignore:

Neurological Troubles

(i.e., confusion, dizziness, weakness)
DAN puts these at the top of its list of symptoms you should worry about. These are signs that you may have decompression sickness affecting your spinal cord or brain, and that’s considered serious and severe. Seek immediate medical attention.

There are a few symptoms diver should never ignore.

iStockphoto

Chest Pain, Breathing Difficulties, Hoarseness

Heart attack is one of the most common causes of death underwater. If you have some undiagnosed heart-disease risks (like high blood pressure and hardening of the arteries), the stress of diving can overload your system and leave your heart without enough oxygen, which brings on what we know as a heart attack. Never, ever ignore chest pain before, during or after a dive. Even if your ticker is running like a Timex, chest pain also may be a sign of another serious event known as pulmonary barotrauma–literally lung damage caused by overinflation of the lungs (usually caused by holding your breath while ascending). The result is that air bubbles leak out and enter the blood, which can cause pulmonary embolism or arterial gas embolism, both very serious and potentially fatal conditions. Again, seek medical help ASAP.

Belly Pain

We’re not talking about garden-variety gas here, but girdle- or corset-like abdominal pain that hurts all the way around and comes on within minutes of a dive. “This is the type of mild [but new and unusual] symptom that comes on rapidly and that deserves attention,” says Freiberger. “I would move rapidly to recompress a person with this symptom because it’s been associated with the development of severe spinal cord involvement minutes to hours later.” In other words, that little something can turn into a big something if you ignore it.

Compromising Pain

Joint pain can be easy to dismiss because you’re moving your bones through so many strange positions during a dive as you hoist heavy tanks, climb ladders, shoulder overstuffed bags, and so on. “If you have low-grade shoulder pain that feels better when you massage it, it’s probably OK,” explains Pollock. “If you can’t raise your arm more than a few inches, that’s a problem.” As a rule of thumb, if it hurts enough to compromise your physical abilities, get it checked.

READ MORE: How To Perfect Your Buoyancy Control

Tingling

(as a side symptom)
Your hands and feet can tingle for lots of reasons. You got too cold. Your wetsuit is too tight. They fell asleep while you were sitting in some awkward position on a hard bench. But if you have tingling in your skin along with other symptoms like numbness, weakness and (obviously more seriously) paralysis anywhere, it can be a sign of serious DCS or arterial gas embolism; take it seriously.

Headache

(as a side symptom)
Obviously, you don’t want to be running to the chamber every time you have a boomer behind your eyes. Headaches are the dandelions of diving; you find them all over the place and they’re hard to completely resolve. But if your throbbing head is accompanied by skin rash, joint pain, swelling, itching, dizziness, nausea, tunnel vision, blind spots, weakness, exhaustion or other troubling symptoms, it’s likely DCS and needs attention.

Skin Mottling

We’re not fish, so our skin is bound to look a little funny when we’re done with a long day of being waterlogged. But anyone who’s soaked in the bathtub too long knows what that looks like. If you have spotty skin discoloration, mottled or marbled-looking skin, that’s likely a skin hit. Skin bends are also accompanied by itching or the feeling of little bugs crawling over you. Though minor skin hits may not require treatment, more serious problems can pop up, so it’s important to be evaluated by a medical professional.

Finally, no list like this can be completely comprehensive. For other symptoms not covered here, always refer to rule No. 1: If it’s unusual, new or intense, pay attention. A minor nosebleed or reverse squeeze is a common occurrence. Crippling pain never is. Use your head and stay safe.

Well, now what? on Tetis.ru

Decompression sickness can overtake anyone. Read about what to do if you think this has happened to you.

Step 1 – Check for symptoms

Do you feel numbness, skin tingling, dizziness, joint pain, chest pain, unexplained fatigue, shortness of breath and shallow breathing? Usually these symptoms appear 15 minutes to 12 hours after diving, but in the most severe cases they may appear while you are still in the water. You may recognize several symptoms or just one of them.

Step 2 – Don’t dismiss the problem

Don’t wait for your symptoms to get better. Do not be shy! Don’t think, “This can’t happen to me” just because your computer doesn’t show that there was a no decompression violation. The algorithms of decompression meters are based on averaged data, the accuracy of their readings is not one hundred percent. There are cases when the computer did not give a warning, and the diver was subjected to decompression sickness.

Rely more on your head than on your computer. Decompression sickness requires immediate treatment. Delaying procedures can result in either more serious health consequences or longer treatment and recovery times.

Step 3 – Tell your divemaster

Report your problem to the divemaster who escorts the group, the dive boat captain, or someone in charge of diving. Describe all the symptoms and everything you feel.

Don’t play down your problems!

If the divemaster does not take your claims seriously, be firm and continue to insist on medical examination and treatment (if necessary). You are the one who feels the symptoms and the divemaster must believe you. The person responsible for the dive must provide timely necessary and sufficient medical assistance to the victim.

Step 4 – Use Oxygen

Breathe 100% oxygen or a gas mixture with as much oxygen as possible, as long as the ship’s supply is sufficient. Lie on your back or follow the divemaster’s instructions. Try not to move.

Step 5 – Call or radio the nearest emergency medical service

Someone should contact a specialized medical service immediately and get you transported to a medical center or recompression chamber as soon as possible.

Step 6 – Contact DAN

The Divers Alert Network (DAN) Hotline is available 24 hours a day at (919) 684-4DAN or (919) 684-43-26.

In addition, you can seek the help of any qualified person who can help you properly assess the situation and the risk of decompression sickness.

DAN staff can advise you on which service is best for you, as well as where and how to access our global network of over 300 recompression stations. DAN operators can ensure your immediate evacuation from the scene to the nearest medical center.

Please note that divers not insured by the DAN network will bear 100% of the costs associated with their evacuation and treatment.

Step 7 – Keep your computer with you

Don’t forget to take your computer to the hospital or recompression chamber. His testimony will help doctors more correctly and accurately assess the extent of your disease.

Before the dive boat leaves the pier, check for:

1. Oxygen (Oxygen). Make sure the boat has oxygen, not empty cylinders.
2. Radio (Radio). And also someone who knows how to use the means of communication.
3. First aid kit (First-aid kit). As well as someone trained in first aid.

Diving & Tropics | Clinic Rassvet

During my vacation I would like to try diving. What should I pay attention to in terms of health, and what dangers, besides drowning, can lie in wait for me?

Problem: hypothermia

The body loses heat 25 times faster under water than in air. Therefore, in water, which always has a temperature below the average temperature of the human body, a spasm of the blood vessels of the skin occurs to reduce heat transfer. The diver feels this as “getting used to” the cool water. However, if you stay in the water for too long, vasoconstriction alone will not be enough, and the second warming mechanism will turn on – muscle contraction, which is felt as a strong trembling. If you ignore the symptoms of heat loss, hypothermia develops with increased trembling, loss of sensation in the limbs. Hypothermia develops when body temperature drops to 35*C, a further decrease in body temperature significantly reduces a person’s ability to adequately assess the situation, and body temperature below 32*C is life-threatening.

How to avoid: special “wet” suits made of neoprene of different thicknesses are used to protect against cold underwater. The thicker, the warmer. The suit should fit in size, too tight will impede movement, too spacious it will be cold due to an excessive layer of water between the skin and the suit. If you are prone to freezing in everyday life, choose a thicker suit. Use hoods – up to 25% of heat loss comes from the head. If you feel that you are cold – interrupt the dive, go up to the land, warm up.

Problem: ear barotrauma

Under normal conditions, a person does not feel air pressure on the body. However, when the pressure around changes – for example, in an airplane while climbing – often there is a feeling of congestion in the ears. Since water is much denser and heavier than air, when diving even to a shallow depth, the environmental pressure on the body increases. The tympanic membrane is a partition between water on one side and air in the tympanic cavity on the other side. Since the water presses on the outside of the eardrum more than the air on the inside, the eardrum flexes inward, compression of the middle ear cavity occurs, and the diver experiences ear discomfort. If you do not correct this situation, you can get an injury to the eardrum. The most significant pressure fluctuations occur at a shallow depth (most often at the level of 4. 5 – 6 m).

How to avoid: equalize the pressure. To do this, pinch your nose and exhale gently through it. At the same time, the air exhaled from the lungs through the auditory tube enters the middle ear cavity, the pressure in it increases, the eardrum takes its normal position, the pain disappears. This manipulation is called “blowing”. It is very important to start blowing at the very beginning of the dive and repeat this procedure several times as the depth increases. It is better to practice in advance, still on dry land. If during the dive at some point it is not possible to blow out, and the pain in the ears increases, you need to rise a little higher to reduce the pressure.

Important: If at the time of diving the diver has a runny nose of an infectious or allergic origin, the auditory tubes, as well as the paranasal sinuses, may be blocked by edema or mucus. In this case, blowing out will be difficult or impossible, and excessive force when blowing can also lead to injury to the eardrum. If the dive is successful, the diver may experience pain in the sinus area – between the eyes, in the upper jaw, forehead area. It is better to refrain from diving until recovery.

Problem: nitrogen narcosis

On land, we breathe air containing about 21% oxygen, 78% nitrogen and about 1% other gases. Nitrogen is a gas that the body does not normally use in any way. The chemical compound of nitrogen – nitrous oxide – is used in medicine for inhalation anesthesia. It is also referred to as “laughing gas” because low concentrations of nitrous oxide cause a mild inebriation and drowsiness. In water, under high pressure, nitrogen can have a similar effect on a person. The diver may develop unusual cheerfulness, nervousness, slowing down of motor reactions and mental activity, it becomes difficult to control buoyancy, to monitor instrument readings. These symptoms increase with increasing depth. If you do not track the first signs in time and do not take action, nitrogen anesthesia can cause disorientation, dizziness and loss of consciousness underwater.
For what reasons nitrogen affects the human body under water in such a way, why this happened to one diver, but not to another, swimming nearby, scientists cannot answer at the moment. It has been established that at depths shallower than 18-24 m, divers do not experience this phenomenon.

How to avoid: getting out of nitrogen anesthesia is quite easy – you need to slowly rise to a shallower depth, and all symptoms will disappear without leaving consequences. However, in order to do this, it is important to notice and correctly assess the first signs of the emerging impact of nitrogen. Therefore, next to an inexperienced diver, there should always be a professional dive guide, whose task is not only to show interesting objects, but also to monitor the safety of the dive. Don’t dive alone. Let your dive guide know if you experience unusual sensations underwater. Nitrogen anesthesia is one of the main reasons why recreational divers are not allowed to dive deeper than 30m. Do not seek to break this rule in the hope of “maybe”. It is possible to overcome this limit after passing the appropriate theoretical and practical training, with the acquisition of diving experience.

Problem: decompression sickness

The risk of developing decompression sickness is associated with the fact that under water a person breathes at a high partial pressure of nitrogen, and the deeper it is, the higher it is. Harmful nitrogen bubbles form in a diver’s body if he ascends too quickly from great depths. When a diver ascends slowly, the nitrogen dissolved in the blood has time to gradually exit through the lungs. At the same time, it must be remembered that if you hold your breath when ascending, the expanding air will not be able to leave the lungs naturally and will begin to look for others. If the ascent occurs quickly, the pressure drops sharply, nitrogen passes into a gaseous state in the blood, with the formation of a bubble in organs, tissues and blood vessels. The most famous everyday illustration of this process is a bottle of champagne. In a closed bottle, the drink is transparent, without bubbles, since the gas is dissolved in the liquid under pressure. If you open the cork, the pressure in the bottle drops sharply, the gas passes from a liquid state to a gaseous state with the formation of bubbles.

Symptoms of decompression sickness depend on where the blisters form:

• if in subcutaneous capillaries, itching and skin rash;
• with lung damage – shortness of breath, cough, burning in the chest;
• with the formation of bubbles in the muscles and joints – pain;
• dizziness, paralysis, visual disturbances, loss of consciousness are formidable signs of brain damage.

Usually the first symptoms appear immediately after ascent, in the interval from 15 minutes to 12 hours. However, signs may appear later if the diver flies an airplane or climbs high into the mountains shortly after the dive.

How to avoid: When ascending, breathe evenly, as usual, inhaling and exhaling without holding your breath, so that “excess air” freely leaves the lungs. Ascend slowly, allowing nitrogen to be released from tissues and blood without going into a gaseous state. Make a safety stop – at a depth of about 6 m, stop for 3-5 minutes. Do not plan dives the day before flights or mountain climbs. Treatment of decompression illnesses is carried out by recompression in special hyperbaric chambers, so check the location of the nearest medical center equipped with a pressure chamber in advance when planning a dive.

Important: Tissue uptake and elimination of nitrogen can be adversely affected by fatigue, sleep deprivation, medication, alcohol or drug use, as well as infectious diseases and dehydration. It should be noted that dehydration often accompanies traveler’s diarrhea, even if it is mild. In most cases, diving takes place in countries with a warm and hot climate, often with an insufficient level of hygiene. To prevent diarrhea and dehydration from spoiling your diving experience, follow these general preventive rules:

• drink only bottled water, more than usual when diving; remember that ice cubes for drinks can be made from raw water;
• wash your hands with soap and water as often as possible, use sanitizers;
• wash fruits and vegetables thoroughly before eating with hot water;
• store food at a safe temperature;
• eat well-cooked food;
• if vomiting and/or diarrhea develops, use oral rehydration solutions;
• When planning a trip to tropical countries, do not forget about the risk of contracting hepatitis A. The virus is easily transmitted through the alimentary route through contaminated food and water, affecting about 10 million people worldwide every year. You can protect yourself in advance with the help of vaccination: two injections of the vaccine Havrix 1440 or Avaxim-160 with an interval of 6-12 months will provide you with protection for a period of at least 25 years. Vaccines are approved for use from the age of 1 year.

Problem: Potentially dangerous marine life

Under normal conditions, no underwater inhabitants consider a person as food, people are too big for this. Most often, the resulting injuries are the result of inattention, negligence or aggressive behavior of the diver himself. Lovers of touching everything can stumble upon fire coral and get a serious painful burn; the phlegmatic beauty lionfish, with which it is so beautiful to be photographed, is the owner of poisonous thorns. If you grab onto the surface of coral reefs, you can prick yourself on the spikes of the master of disguise – the scorpion fish or its close relative – the stone fish, whose poison is very dangerous. If a diver wants to take away a souvenir from the day of the sea, he can turn up a very beautiful shell – a silk cone that shoots a poisonous sting hidden inside, and this can be fatal. Wounds inflicted by a stingray thorn, sea urchin needles heal for a long time, jellyfish burns are painful, and some jellyfish are even poisonous.