What Are The Bends In Scuba Diving?
One of the few risks to be aware of when scuba diving is the bends, also known as decompression sickness. Every diver out there dreads The Bends, and we all take a number of precautions to help ward it off every single time we dive, but what exactly is it, and how do we avoid it?
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What Are The Bends In Scuba Diving?
Decompression sickness, also known as “the bends,” is well-known both within the diving community and in general culture, but most people are unaware of what it actually means. Also known as Caisson disease, it is a condition that does not occur in freediving, but can happen when a diver is using a breathing regulator. The symptoms can affect virtually any part of the body, including the joints, lungs, heart, skin, and brain.
The bends are caused by dissolved gases (primarily nitrogen) that bubble up out of solution as a result of decompression in scuba divers, high altitude events, or aerospace phenomena. Joints, lungs, hearts, skin, and the brain are just a few of the body parts that they can harm.
F.C. classified the symptoms of the bends, also known as decompression sickness. As of 1960, Golding was:
- “Type I (‘simple’)” for symptoms involving only the skin, musculoskeletal system, or lymphatic system”
- “Type II (‘serious’)” for symptoms where other organs (such as the central nervous system) are involved.”
While the bends are becoming much less common than they once were, they can still be very serious if contracted. Exposure to the bends can be managed through proper decompression prevention.
Divers control their ascent speed and prevent decompression sickness by using computers and tablets.)
What Causes The Bends?
The pressure is higher underwater than it is at sea level when you are diving.
The gases in your air tank could dissolve into the tissues of your body as you dive due to the pressure. “On-gassing” is another name for this.”
The pressure will then decrease as you surface, and the gases should gradually escape the tissue. This is frequently referred to as “off-gassing.””
The gas won’t safely exit your body’s tissues, though, if the ascent is too rapid. Instead, it will form and hold onto tiny bubbles of it. The bends are a result of this.
Think of it as a bottle of soda. Everything is fine inside the pressurized, closed bottle. When the top is removed and the pressure is released, the carbon dioxide bubbles in the beverage only begin to fizz out in full.
Nitrogen is the problematic gas, though any type of gas in a diver’s tank can be impacted in this way. As a result, nitrogen is useless to your body. All it does is accumulate in the tissues, obstruct healthy blood flow, and strain or harm the nerves.
The released gas can also result in an embolism, blood clotting, or the release of vasoactive compounds, which are substances your body naturally produces and which can lower or raise blood pressure or heart rate.
These factors raise the risk of DCS:
- The depth of the dive
- The duration of the dive
- The rate of ascent
What Are The Bends’ Symptoms?
Depending on the person, the bends symptoms can range from minor to excruciating and necessitate varying degrees of treatment. When diving, if someone exhibits any of these signs, you should give them an oxygen mask as soon as you can and get help from a doctor.
Muscoskeletar -localized, intense discomfort as well as joint pain. A dull ache can occasionally be excruciating.
Skin– Face, neck, and upper body itching. Skin occasionally has a marbled or puffy appearance.
Fatigue – a profound sense of fatigue.
The Chokes -Shortness of breath, chest pain, a dry cough, and breathing difficulties.
The Staggers – hearing and balance problems, nausea, vomiting, and dizziness.
How Do You Treat The Bends?
Decompression sickness treatment should be sought out right away if you or anyone diving with you exhibits any of the possible bends symptoms.
In order for the physician or staff at the emergency care facility you visit to be aware that DCS is a likely cause of your condition, it is crucial to inform them that you have been diving within the previous 48 hours.
Professional treatment for the Bends
The tool required to treat DCS is a hyperbaric recompression chamber:
- Depending on how severe the symptoms are, hyperbaric treatment can last up to 12 hours or longer.
- The pressurized environment of the chamber causes the bubbles to condense and aids in their absorption.
- Additionally, it gives the tissues that have been damaged a lot of oxygen.
Before beginning therapy in the re-compression chamber, the patient will typically undergo testing and have IV and oxygen lines attached.
The next step is likely to be hospital admission for status monitoring.
Emergency care for DCS
Your first port of call whenever a case of the bends is reported should always be the local emergency services.
Make sure the professional you are speaking to comprehends:
- Decompression sickness affects the diver.
- They must be moved while lying flat on their backs.
- If possible, the vehicle should travel below 1000 feet when being airlifted, or it should be pressurized to sea level.
- They will be taken to a hospital that needs to have a hyperbaric chamber because it will almost certainly be necessary for their treatment there. On the Divers Alert Network website, you can conduct an online search to find the closest chamber to you.
There are a few things you can do to keep someone with the bends stable until assistance arrives if you are absolutely unable to get them to a hospital in time:
- 1. Keep them warm with blankets if their body temperature drops.
- 2. Don’t forget to put their oxygen mask on if you have one.
How Can The Bends Be Prevented?
Divers must control their ascent rate and follow a decompression schedule as needed to prevent decompression sickness by stopping the release of bubbles that can harm the body.
Divers must stay at each specific depth until enough gas has been eliminated from the body; each of these is referred to as a decompression stop; this is necessary for them to safely ascend from a deep scuba diving session.
Divers use dive computers, decompression tables, and decompression software to precisely measure decompression stops both before and during a diving session. These are frequently built using a mathematical model of the body’s inert gas absorption and release under varying pressures.
During the decompression phase of the dive, breathing mixtures with significantly less inert gas can help reduce the amount of time needed for decompression before ascending.
Other Things Keep The Bends Away
- Always begin your ascent at least a few minutes before you reach the limits set by your dive computer. Never dive right up to them.
- The more senior you get, the less effective your circulatory system is, which has an impact on nitrogen elimination.
- You should be aware that because nitrogen is easily dissolved in fat tissue, chubby funbodies may absorb more nitrogen when diving if you’re a bit of a fatty (or big-boned like me).
- While diving in cold water, your circulation may decrease as your extremities cool, which will affect nitrogen removal.’
- Avoid diving while high or intoxicated! This is something we should never do because not only will it impair your judgment, but it will also dehydrate you and increase your heart rate, increasing the likelihood of those annoying bubbles forming.
- After a dive, a hot shower or bath will cause your capillaries to enlarge, drawing blood away from other areas and causing your body to expel nitrogen more slowly.
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When Scuba Diving What Are the Bends?
The bends also known as Decompression Sickness (DCS) is one of the most common injuries in scuba diving. If you are new to scuba diving and the terms used you are probably wondering what are the bends.
When scuba diving the bends are a term used to refer to injuries resulting from nitrogen bubble buildup in the body tissues or in the bloodstream. This happens when scuba divers ascend very fast, fly too soon after scuba diving or participate in activities such as hiking to high altitudes immediately after scuba diving.
The bends is a term initially used to describe the illness resulting from nitrogen buildup in the body. Probably due to the fact that those with the illness tend to suffer from joint pain which can cause bending.
Today the term Decompression sickness (DCS) is widely used but there is no harm in using other terms such as ‘the bends’. When talking to someone with scuba diving experience or a doctor they will understand you perfectly.
The bends can onset immediately after surfacing or take up to 48 hours to show any signs or symptoms. Depending on the individual it’s important to keep an eye on your health and seek medical attention if you notice any signs or symptoms of DCS.
In this article, we’ll look deeper into DCS, what happens when you get DCS, at what depth you can DCS, and how to treat and prevent the illness among other factors.
Keep reading to learn more!
What Do the Bends Feel Like
The bends or decompression sickness can range from mild body aches to very painful joints.
Some scuba divers describe the bends as very uncomfortable, one feels like something is stubbing you from inside their body.
The severity of the bends differs causing differences in how each diver feels. In mild cases this can feel like you are just tired or experience dull body aches, in severe cases, the feeling will vary from sharp back pains, ear pain, skin irritation, confusion, blurred vision, nausea, ringing ears, and memory loss.
Every diver with the bends is most likely to describe a unique feeling of what their body is going through. We all have different tolerance levels to pain which can also cause differences in how one feels.
However, some symptoms are quite common among all divers with the bends. Some of these may include unexplained fatigue, and body, and joint aches.
First-time divers are particularly encouraged to look out for any symptoms that may suggest one has the bends. Since it’s your first time diving you may lack the knowledge of what it feels like or what to look out for.
Experienced divers can easily note when thy have the bends or when their buddy shows symptoms.
It’s also very common for divers to be in denial of having the bends. For this reason, it’s important to look out for your buddies even after the dive.
What Depth Do You Get the Bends
Anyone can get the bends if your ascent was fast despite the diving depth.
Decompression sickness is however most common among deep divers. This is because they use highly compressed air (enriched air) such as oxygen mixed with helium or nitrogen.
Divers diving over 60 ft. have a higher chance of developing DCS if they fail to ascend properly. At these depths, divers use highly compressed air which increases the chances of absorbing a lot of nitrogen during the dive.
In addition, depending on the dive length divers will absorb more nitrogen in the body. When a diver spends more time underwater, they need to spend more time ascending.
Dive computers and dive tables guide divers on how much time they can safely spend at given depths and how much time they will need to ascend.
Making stops during the ascent is necessary to allow for off-gassing of the excess nitrogen.
Recreational scuba divers also follow the guidelines provided to prevent the bends. This is important since pressure changes as we dive underwater. Air pressure in the air cylinder also increases compared to the air we breathe while at sea level.
This change in pressure increases the amount of nitrogen absorbed even at 30 or 20 ft. underwater.
Ascending correctly and following the dive computers or tables, it’s quite easy to avoid “the bends”
What Happens When Scuba Divers Get The Bands?
When drivers fail to follow the dive tables or computers and ascend too fast, the body fails to release the excess nitrogen. Dissolved nitrogen turns into bubbles during the fast ascend which remains trapped in the joints, body tissues, and the bloodstream.
When this happens it’s said the diver has the bends, signs, and symptoms will appear after surfacing.
Think of an ascending scuba diver as a shaken bottle of soda or any other carbonated drink. Opening the bottle the drink comes out at very high pressure in form of bubbles. This same principle applies to ascending for scuba divers.
Nitrogen absorbed turns into bubbles as it tries to get out of the body. There are other risks associated with fast ascend such as gas embolism.
Some scuba divers will notice the symptoms within an hour after surfacing or less. In other individuals, it may take up to 36 hours before any sign is visible.
When a scuba diver has the bends they may feel very tired after doing absolutely nothing or very light activities. Other divers will feel joint pains, experience difficulty breathing, confusion, losing balance, back pains, and ear pain among other signs and symptoms.
Upon noticing these signs, seek immediate medical attention. Divers are advised against taking any pain relievers unless prescribed by the doctor.
During the intervention period, it’s important to record all signs and symptoms visible. Rerecord activities done after the dive, any occurrences during the dive such as emergencies that may have resulted in fast-paced ascent among others.
All this information is important to help in the treatment and also access the severity of the bends.
How Are the Bends Prevented and Treated
Luckily the bends can be prevented and treated if addressed immediately.
As mentioned above, denial is very common among divers. Look out for your buddies for any signs or symptoms of the bends. The goal is to address the issue as soon as it’s noticed.
Preventing the bends
To prevent the bends, always dive with professionals from reputable agencies. These are especially important for beginners and first-time divers. The instructors guide you on how to ascend making necessary stops to allow enough off-gassing.
Get certification or training with a qualified diving agency. Certifications in diving equip divers with all necessary skills to safely scuba dive. Certification shows you have knowledge of what is expected of you and that you are aware of the risks involved.
Follow dive tables or dive computer guidelines when ascending and when taking multiple dives in a day.
Other ways to prevent the bends include, taking time to off gas before flying to your next destination. Avoid hiking immediately after scuba diving since this can have the same effect as flying after scuba diving.
Chang in altitude and pressure can onset DCS as it’s like a fast-paced ascent. It’s recommended to at least have 18-24 hours after scuba diving before you can fly.
Treating the Bands
When addressed as soon as possible the bends are easily treated and full recovery is seen among divers.
Call the nearest medical facility for help when you or your buddy has DCS signs and symptoms. Next contact the local DAN.
Divers in denial or who take some time to see if the signs go away are putting their lives at risk. If not treated early, the bends can be fatal.
Treatment includes administering 100% oxygen, and fluids. This helps in recompressing and stabilizing the diver.
Dives with DCS then receive a neurological exam to establish if any of the nervous parts are affected and could need special treatment.
Rashes or pain on specific body parts could be an indication of a neurological issue.
Can You Survive the Bends
Yes, you can survive the bends. Many dives have at one point had the bends and many recover fully.
Staying alert and taking note of any unusual feeling in the body is important in surviving the bends. Don’t ignore anything unusual or feel shy to seek medical advice. I would rather feel stupid asking if what I’m feeling could be the bends than ignore the signs and put my life at risk.
Many severe and fatal cases of the bends happen when divers are in denial that they have the bends or by simply ignoring the early signs.
Remember you can get the bends even after following the required ascend rates and guidelines. You can also get the bends even as an experienced diver.
We’ve looked at what are the bends in scuba diving, what happens when you get the bends, and how to prevent and treat the bends.
Although the most common injury among scuba divers, you can fully recover and go on scuba diving. The most important thing to do is seek immediate medical attention once you notice any of the signs associated with the bends.
I hope this article provides useful information on the bends and how to prevent them.
Can You Get The Bends From Freediving?
Freediving can be an extremely safe sport if participants learn and follow safety guidance, including measures to lower the risks of DCS. You should always exercise care while freediving and remain within your competence for length and depth of dive, gradually increasing these as your skill and physical capacity grow.
You can get “the bends”, the informal term for decompression sickness, from freediving, although it isn’t as common as in scuba diving. Some people may naturally have a greater vulnerability to DCS than others. Diving very deeply, diving for long periods and taking multiple dives over a short period, are amongst the factors which can increase the risk of decompression sickness.
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Many people still think that only scuba divers are at risk of the bends, or decompression sickness (DCS), caused by nitrogen bubbles forming in the body on diving ascent. Time to think again! Even though freedivers are not inhaling compressed air or other gas mixtures which saturate the body with nitrogen, they could still develop DCS from a single lungful of ordinary air, especially during longer, deeper dives.
At what depth do you get the bends freediving?
There is no single absolute depth limit beyond which you will definitely develop the bends while freediving. Similarly, while DCS risk rises with depth, limiting yourself to shallower dives doesn’t confer 100% protection. Length of dive, physical characteristics and environmental factors may all have an influence on the chances of getting the bends.
Common advice is that whatever the depth of your freedive, you should spend at least three times your dive time in recovery on the surface between dives. For example, after a two minute dive, you should wait 6 minutes at the surface before undertaking another dive.
Can you get the bends in 30 feet of water?
You can get the bends in 30 feet (around 9.1 meters) of water. While the bends is less likely to be an issue while diving in shallower water, it is still possible.
Some people may have a greater predisposition to DCS than others due to innate, lifestyle or environmental factors and therefore may be at risk of triggering some degree of DCS even at 30 feet. Dehydration, cold and a high carbon dioxide level could all raise the risk of getting the bends.
Length of dive and number of dives are also significant risk factors for DCS as well as depth. Undertaking multiple shallow dives over a longer period without sufficient rest time at the surface, may lead to accumulating more dissolved nitrogen in the bloodstream than undertaking a single shallow dive.
No matter what the depth of dive, spearfishers, recreational freedivers and competitive divers should all take care to limit the duration of their dives, rest sufficiently between dives and stay warm in the water.
If you’re thinking of diving at a 30 feet depth, we’ve written a whole article on freediving at 30 feet (opens new tab) which you should find useful.
Can freedivers get decompression sickness?
Decompression sickness is another name for the bends, a condition affecting divers which can cause pain, serious injury, or even death. While causal links between freediving and DCS are still the subject of research, there is significant evidence connecting them. The US National Institute of Health (NIH) has recorded over 90 cases of freediving-linked decompression sickness.
The air that we breath is made up of 78% nitrogen, 21% oxygen, and 1% other gases. Both oxygen and some nitrogen dissolve in the blood under normal pressures at sea level. When someone freedives, the massive pressure of the water on their body including the lungs, causes higher levels of both nitrogen and oxygen to dissolve into the bloodstream as they descend.
Oxygen in the bloodstream will be gradually consumed by the body during a freedive, but the nitrogen remains there. If they ascend slowly, this should allow nitrogen to dissolve gradually and safely out of the blood and body tissue. Ascending fast reduces pressure on the body too quickly and allows nitrogen gas to dissolve out from the bloodstream and be released as bubbles.
These nitrogen bubbles can cause painful blockage of blood vessels in limbs, rupture lung blood vessels, or trigger a heart attack or stroke.
Getting on an airplane shortly after diving, while dissolved blood nitrogen levels might still be higher than normal, could also trigger or worsen DCS. Ascending quickly to a great height, with commensurately lower air pressure, has similar effects as ascending too quickly in water. After scuba diving or freediving, you should allow a waiting period before getting on a plane to allow excess nitrogen to leave the blood.
How deep can you freedive without decompression?
We know that the deeper you dive, the greater the pressure exerted on the body by water, the more nitrogen may dissolve in the bloodstream, and the greater the risk of getting DCS. However, it’s difficult to give an exact figure for how deep you can dive before needing to make decompression stops on ascent.
Decompression stops are one way in which scuba divers mitigate the risk of DCS during their ascent. The term means pausing for a short period at each stage return to the surface, in order to allow the body to adjust and nitrogen levels in the blood to reduce.
During shallower freedives, decompression stops are not necessary. When diving moderately deeply, it’s better for freedivers to ascend slowly rather than stop completely. On very deep freedives (e.g. during elite “no limits” freediving competitions), decompression stops are very definitely necessary, and you should plan carefully these with your diving buddy or support team according to depth and your own previous experience and competence.
The deepest freedive on official record was a “no limits” freedive by Herbert Nitsch which reached a depth of 253 m (830 ft) in 2012. Nitsch developed DCS after this extremely deep dive, even while trying to make decompression stops.
How slow do you have to ascend to avoid the bends?
Freedivers should ascend at a moderate speed of 1m/s (3ft/s) or less, slowing down further during the last 10 meters. This should give nitrogen dissolved in your blood sufficient time to dissolve out without forming dangerous bubbles.
How to avoid the bends freediving
There are a number of measures you can take to help avoid developing the bends while freediving. These include: