Since bubble formation is an uncontrolled process, they can develop anywhere in the body, common sites being the shoulders, elbows, knees, and ankles. In most cases of altitude decompression sickness, the person generally complains of joint pains ("the bends") in which shoulder is the commonest site. When large joints like elbows, shoulders, hips, wrists, knees and ankles are involved, the person complains of localized deep pain that can be mild to excruciating. It is seen that active as well as passive movement of these joints increases the pain. Sometimes the pain can be reduced by bending the joint to a more comfortable position. If the pain is caused due to altitude change, then it can occur immediately or sometimes later too.

Neurological symptoms of headache and visual disturbances are present in 10% to 15% of decompression sickness cases. Cutaneous symptoms are seen in 10% to 15% of cases. The patient may suffer from altered sensation of paraesthesia or hyperesthesia. Confusion, amnesia, seizures, unconsciousness and unexplained mood changes can be seen. The person complains of itching generally around the ears, face, neck, arms and upper torso. Weakness or paralysis of legs, incontinence of urine and stool may be present. The patient may complain of a feeling of tightening or bending in the abdominal region. Generalized malaise and unexplained fatigue are commonly seen. Nausea, vomiting, dizziness, vertigo, hearing loss and loss of balance are present due to involvement of the inner ear [16]. Diver may complain of altered sensations as if tiny insects are crawling on the skin. Skin appears mottled or marbled along with itching at different sites. Swelling of the skin along with pitting edema. Pulmonary decompression sickness ("the chokes") is rarely seen in divers and is all the more rare in aviators because of oxygen pre-breathing protocols being introduced. The person may even complain of dry persistent cough and shortness of breath.

• Fatigue

  Symptoms can include fatigue and pain in muscles and joints. In the more severe type, symptoms may be similar to those of stroke or can include difficulty breathing and chest pain. [merckmanuals.com]

  […] commonly in divers; however, it can occur in aviation incidents, which this case report will discuss.CASE REPORT: Following an acute cabin depressurization incident, 36 patients presented to a small outpatient clinic with multiple symptoms, including fatigue [ncbi.nlm.nih.gov]

  ‘Diving while your body is dehydrated leads to aching muscles, fatigue and even decompression sickness - it's that serious.’ [en.oxforddictionaries.com]

  Fatigue is not uncommon after dives and by itself is not treated as VGE. If it is unusually severe, then there should be cause to do a complete neurological exam. A stricken diver may feel fatigued, or weak and attribute it to working to hard. [rescuediver.org]

• Unconsciousness

  Symptoms occur soon after the dive has finished and, in the most serious cases, it can lead to unconsciousness or death. [netdoctor.co.uk]

  He became unconscious and recovered after an emergency descent. The pilot collapsed and a pulmonary edema occurred 8 h after landing. [ncbi.nlm.nih.gov]

  If necessary (e.g., if the diver is unconscious), begin CPR and take immediate action to have the diver evacuated. Check for foreign bodies in the airway. [diversalertnetwork.org]

  This is extremely dangerous and can be identified by symptoms such as blurred vision, headaches, confusion and unconsciousness. [scubadiverlife.com]

• Malaise

  […] activation(17,18) and leukocyte-endothelial interaction.(19) The diagnosis of DCS is made on the basis of signs and/or symptoms after a dive or altitude exposure.(8) Manifestations most commonly include paresthesias, hypesthesia, joint pain, skin rash and malaise [uhms.org]

  […] obstruction tissue distortion causing pain embolisation (25% of people have PFO so can embolise to the brain) CLINICAL FEATURES cough -> respiratory failure Type I Decompression Sickness musculoskeletal pain (limbs, shoulders, elbows, hips, knees) anorexia malaise [lifeinthefastlane.com]

  People with DCS may also have headaches, dizziness, extreme fatigue, ringing in the ears, visual problems, chest pain and shortness of breath, a skin rash and itching, and malaise. [urmc.rochester.edu]

• Limb Pain

  Although the majority of cases are manifested by joint or limb pains (Type I DCS), patients may present with a wide array of symptoms, such as neurologic deficits, headache, fatigue, nausea, and respiratory difficulty. [ncbi.nlm.nih.gov]

  Joint and Limb Pain Decompression Sickness Aching and/or pain in the joints characterize type 1 DCS. The pain can be in one place or it can move around the joint. [scubadiverlife.com]

  Bubbles causing limb pain cannot be detected radiographically. Neither imaging nor neurophysiological studies should be relied upon to confirm the diagnosis of DCS or be used in deciding whether a patient with suspected DCS needs HBO2. [uhms.org]

  Joint and Limb Pain Decompression Sickness: This type is characterized by aching in the joints. It is not known precisely what causes the pain as bubbles in the joint would not have this effect. [scuba.about.com]

  Joint and Limb Pain Decompression Sickness : This type is characterized by aching in the joints. It is not known exactly what causes the pain as bubbles in the joint would not have this effect. [sssnetwork.com]

• Chills

  Terry Begnoche remembers every chilling second of his rapid rise from 220 feet deep in Lake Superior — how an ascent that should have taken at least 45 minutes took two minutes, how he couldn’t stop it, and how he hit the surface of the great lake knowing [startribune.com]

  Chilling and frostbite may occur if proper protective clothing is not worn or available. (e) Pressure. How Fast Will A Spaceship Decompress If It Gets Punctured? The decompression time will depend on how big the hole is. [geoffreylandis.com]

  Constitutional or Nonspecific: dizziness, fatigue, headache, nausea, vomiting, chills, diaphoresis, malaise, restlessness. [journals.plos.org]

• Cough

  […] endothelial activation -> capillary leak increased leukocyte adhesion, inflammatory response and reperfusion injury vessel obstruction tissue distortion causing pain embolisation (25% of people have PFO so can embolise to the brain) CLINICAL FEATURES cough [lifeinthefastlane.com]

  Symptoms include breathlessness, tachypnoea (increase in breathing rate), chest pain and coughing. Although symptoms may resolve, this should be regarded as a life-threatening condition as it may progress to fatal respiratory collapse. [sdm.scot.nhs.uk]

• Dyspnea

  A 51-year-old civilian pilot flying a high performance aircraft for the USAF presented for medical attention approximately 1.5 hours after developing substernal chest pain and dyspnea while flying unpressurized at FL 280 (8,534 meters) for 30 minutes. [ncbi.nlm.nih.gov]

  Symptoms include joint pain, dizziness, staggering, visual disturbances, dyspnea, and itching of the skin. Partial paralysis occurs in severe cases; collapse and insensibility are also possible. [medical-dictionary.thefreedictionary.com]

  More serious signs and symptoms include motor weakness, ataxia, dyspnea, urethral and anal sphincter dysfunction, shock and death.(8,20,21) Severe DCS may be accompanied by hemoconcentration and hypotension.(12-14,16) Severe symptoms usually occur within [uhms.org]

  He had no dyspnea, diaphoresis, visual or auditory symptoms, or alteration in consciousness. There was no previous history of similar symptoms or of pulmonary, cardiac, or neurologic problems. [pilotfriend.com]

• Painful Cough

  Sinus squeeze - Sinus pressure, pain, or nasal bleeding. Face mask squeeze - "Bloodshot" eyes and redness or bruising of the face under the mask. Lung squeeze - Chest pain, cough, bloody cough, and shortness of breath. [webmd.com]

  The chokes (respiratory decompression sickness) is a rare but grave manifestation; symptoms include shortness of breath, chest pain, cough, resulting from pulmonary edema. [merckmanuals.com]

• Tachypnea

  If pulmonary intravascular bubbling (chokes) occurs, the patient will develop symptoms consistent with pulmonary embolus and pulmonary edema with chest pain, tachypnea and cough. [divinghbo.com]

  […] decompression, with intravascular 'boiling' of nitrogen, and resultant morbidity or mortality; DS occurs in scuba divers and high-altitude pilots or workers in high-pressure environments Clinical, acute The 'bends' headache, N&V, vertigo, tinnitus, dyspnea, tachypnea [medical-dictionary.thefreedictionary.com]

• Abdominal Pain

  The patient subsequently presented to the Emergency Room with symptoms of shortness of breath and abdominal pain. [ncbi.nlm.nih.gov]

  Sharp knife like pain shooting down an extremity, or encircling the body, vague thoracic or abdominal pain, or pain moving from one area to another, should be treated as arising from the central nervous system. [rescuediver.org]

  Other symptoms may include fatigue, weak or numb upper extremities, chest or abdominal pains. [emedicinehealth.com]

• Chest Pain

  A 51-year-old civilian pilot flying a high performance aircraft for the USAF presented for medical attention approximately 1.5 hours after developing substernal chest pain and dyspnea while flying unpressurized at FL 280 (8,534 meters) for 30 minutes. [ncbi.nlm.nih.gov]

  Symptoms can include fatigue and pain in muscles and joints. In the more severe type, symptoms may be similar to those of stroke or can include difficulty breathing and chest pain. [merckmanuals.com]

  […] which may be accompanied in mild forms by fatigue and itching or burning of the skin and in more severe forms by shortness of breath, chest pain, paralysis, and confusion — called also bends, caisson disease [merriam-webster.com]

  Chest pain and shortness of breath associated with pulmonary barotrauma may require an ECG and a chest X-ray. [webmd.com]

• Hypotension

  Impaired endothelial function can lead to capillary leak with hemoconcentration and hypotension in severe cases. [ncbi.nlm.nih.gov]

  More serious signs and symptoms include motor weakness, ataxia, dyspnea, urethral and anal sphincter dysfunction, shock and death.(8,20,21) Severe DCS may be accompanied by hemoconcentration and hypotension.(12-14,16) Severe symptoms usually occur within [uhms.org]

  Decrease in blood pressure (hypotension). The resulting cerebral damage may result in the following symptoms. Severe headache. Paralysis. Numbness. Unconciousness. Symptoms similar to those of neurological DCS may also be present. [sdm.scot.nhs.uk]

  Most episodes are clinically silent or result in mild, transient hypotension. Penetrating chest injuries may produce a bronchopulmonary venous fistulae and arterial air emboli. [web.archive.org]

• Cyanosis

  […] cough -> respiratory failure Type I Decompression Sickness musculoskeletal pain (limbs, shoulders, elbows, hips, knees) anorexia malaise fatigue orange appearance of skin from local lymphatic obstruction pruritis (ears, trunk, wrists, hands -> trunk) cyanosis [lifeinthefastlane.com]

  Other symptoms include cough, difficulty breathing, and cyanosis (blue lips and skin) Divers with the chokes can progress to shock rapidly Neurologic Decompression Sickness (these symptoms may be the only DCS signs) The most common area affected in divers [emedicinehealth.com]

  Skin - itching, mottling/marbling, violet colour, cyanosis, or pallor Diagnostic techniques - Pain, frequently musculoskeletal, is present in a substantial number of DCI cases. [londondivingchamber.co.uk]

• Tachycardia

  As the patient then developed sinus tachycardia and with low oxygen saturations, a pulmonary embolism was imaged for by CTPA which was negative. [jintensivecare.biomedcentral.com]

  Increase in heart rate (tachycardia). Decrease in blood pressure (hypotension). The resulting cerebral damage may result in the following symptoms. Severe headache. Paralysis. Numbness. Unconciousness. [sdm.scot.nhs.uk]

  […] these changes in the pulmonary vascular bed, the following hemodynamic effects may be observed [1,5,12]: • Increased pulmonary vascular resistance • Pulmonary artery hypertension • Increased right ventricular pressure • Initial brief increase (due to tachycardia [web.archive.org]

  Treat the signs of tachycardia and postural hypotension with oral rehydration if the patient is conscious, or intravenously if the patient is unconscious. The treatment of DCS is less effective if dehydrated. [emedicine.medscape.com]

• Arthralgia

  Decompression sickness can be further clinically subdivided into: mild symptoms: arthralgia, skin marbling, small patchy hemorrhages, and lymphatic obstruction serious and life-threatening symptoms: affecting the brain, spinal cord, inner ear, and/or [radiopaedia.org]

  Sign In A 42-year-old man presented to the emergency department with skin changes, arthralgias, and vomiting after scuba diving. He was treated for decompression sickness. Qing Sun, M.D. Guangkai Gao, M.D. [nejm.org]

  […] and potentially death Applies To Bends Compressed-air disease Decompression sickness Divers' palsy or paralysis ICD-9-CM Volume 2 Index entries containing back-references to 993.3 : Aerobullosis 993.3 Aeroembolism 993.3 Air compressed, disease 993.3 Arthralgia [icd9data.com]

  […] in diseases classified elsewhere 2016 2017 2018 2019 Non-Billable/Non-Specific Code Code First underlying disease, such as: caisson disease ( T70.3 ) hemoglobinopathy ( D50 - D64 ) Aerobullosis T70.3 Aeroembolism T70.3 Air compressed, disease T70.3 Arthralgia [icd10data.com]

• Leg Pain

  The symptoms of the bends are varied, but most often include joint, arm, and leg pain. More serious symptoms include dizziness and difficulty speaking or walking. Serious cases of the bends can result in coma or death. [zocdoc.com]

• Skin Rash

  The other symptoms and signs that can be observed are: Blotchy skin rash Fatigue or weakness Skin itchiness Dizziness Shortness of breath Abdominal distress Chest pain Skin swelling The above signs and symptoms may occur when the diver is still underwater [divein.com]

  Symptoms of DCS or AGE can include joint pain, numbness, tingling, skin rash, extreme fatigue, weakness of arms or legs, dizziness, loss of hearing, and in serious cases, complete paralysis or unconsciousness. [virginiamason.org]

  Symptoms Symptoms of decompression sickness include: Joint pain Dizziness Headache Difficulty thinking clearly Extreme fatigue Tingling or numbness Weakness in arms or legs A skin rash Diagnosis Your diving history and symptoms are key factors in diagnosing [drugs.com]

• Pruritus

  […] hours of ascent: 90% Most common symptoms of Neurologic DCS Numbness (59%) Pain (55%) Dizziness (27%) Severe Fatigue (25%) Headache (24%) Weakness (23%) Nausea (14%) Abnormal Gait (12%) Hypoesthesia (10%) Visual disturbance (8%) Vision Loss Diplopia Pruritus [fpnotebook.com]

  Initially, there is erythema accompanied by pruritus, and then the rash spreads irregularly and deepens in color. It develops a mottled appearance, with areas of pallor surrounded by cyanotic patches. During recompression, the rash resolves. [nejm.org]

  Severe itching (pruritus), skin rashes, and skin mottling (cutis marmorata) are other relatively common symptoms. All of these are sometimes classified as manifestations of Type 1 or "mild" decompression sickness. [encyclopedia.com]

• Erythema

  Initially, there is erythema accompanied by pruritus, and then the rash spreads irregularly and deepens in color. It develops a mottled appearance, with areas of pallor surrounded by cyanotic patches. During recompression, the rash resolves. [nejm.org]

  713.3 ] diabetes 250.6 [ 713.5 ] diphtheria 032.89 [ 711.4 ] dracontiasis 125.7 [ 711.7 ] dysentery 009.0 [ 711.3 ] endocrine disorder NEC 259.9 [ 713.0 ] enteritis NEC 009.1 [ 711.3 ] epiphyseal slip, nontraumatic (old) 716.8 erysipelas 035 [ 711.4 ] erythema [icd9data.com]

• Suggestibility

  In line with this scenario is the low probability (approx. 15%) of inner-ear DCS presenting with concomitant symptoms suggestive of brain involvement. [ncbi.nlm.nih.gov]

• Hematuria

  Other symptoms may result from arterial gas embolism in any of the following: Coronary arteries (eg, arrhythmias, MI, cardiac arrest) Skin (eg, cyanotic marbling of the skin, focal pallor of the tongue) Kidneys (eg, hematuria, proteinuria, renal failure [merck.com]

• Dizziness

  Vertigo, dizziness, ringing in the ears, and loss of hearing also may occur, but they are hard to distinguish form ear trauma resulting from squeeze or reverse block. [rescuediver.org]

  Dizziness Divers experiencing DCS may come out of the water feeling dizzy or experience slight to severe vertigo. Along with the dizziness and vertigo, they may hear ringing in their ears. 5. [underseas.com]

  Symptoms: Cerebral Decompression Sickness Onset Within one hour of ascent: 50% Within 6 hours of ascent: 90% Most common symptoms of Neurologic DCS Numbness (59%) Pain (55%) Dizziness (27%) Severe Fatigue (25%) Headache (24%) Weakness (23%) Nausea (14% [fpnotebook.com]

  The decrease in air pressure releases body nitrogen in the form of gas bubbles that block the small veins and arteries and collect in the tissues, cutting off the oxygen supply and causing nausea, vomiting, dizziness, pain in the joints and abdomen, paralysis [infoplease.com]

  This blood vessel blockage causes pain and various other symptoms, for example, sometimes similar to those of a stroke (such as sudden weakness on one side of the body, difficulty speaking, or dizziness), or even flu-like symptoms. [merckmanuals.com]

• Headache

  A 33-yr-old man came to the emergency department with the chief complaint of a severe headache and decreased sensation in his right hand following a deep dive on scuba. [ncbi.nlm.nih.gov]

  Symptoms: Cerebral Decompression Sickness Onset Within one hour of ascent: 50% Within 6 hours of ascent: 90% Most common symptoms of Neurologic DCS Numbness (59%) Pain (55%) Dizziness (27%) Severe Fatigue (25%) Headache (24%) Weakness (23%) Nausea (14% [fpnotebook.com]

• Vertigo

  RESULTS: Significantly higher sway values obtained with the Quantitative Romberg test were observed in the group of DCS with vertigo relative to DCS without vertigo and healthy controls. [ncbi.nlm.nih.gov]

  Initial attempts to man the radar scope caused severe vertigo, nausea, and vomiting obviating his return to work. [armyaviationmagazine.com]

• Confusion

  The diagnosis and management of DCS is frequently a source of confusion. [ncbi.nlm.nih.gov]

  Fuzzy thinking, incoherent reasoning, confusion, and impaired manual dexterity are all symptoms of narcosis. [liveabout.com]

  […] high altitudes in a poorly pressurized aircraft) and that is marked chiefly by joint pain which may be accompanied in mild forms by fatigue and itching or burning of the skin and in more severe forms by shortness of breath, chest pain, paralysis, and confusion [merriam-webster.com]

• Stroke

  In the more severe type, symptoms may be similar to those of stroke or can include difficulty breathing and chest pain. People are treated with oxygen and recompression (high-pressure, or hyperbaric, oxygen) therapy. [merckmanuals.com]

  with implications for stroke or cognitive decline. [ncbi.nlm.nih.gov]

  He immediately went to the nearest medical facility with a hyperbaric chamber, but was told there that he was most likely having a stroke, and was not put in the chamber despite his concerns that it was DCS, and calling the Divers’ Alert Network (DAN) [armyaviationmagazine.com]

  Symptoms of DCS may include: joint pain areas of bone destruction (termed dysbaric osteonecrosis) skin disorders, such as cutis marmorata, which causes a pink marbling of the skin spinal cord and brain disorders, such as stroke, paralysis, paresthesias [cdc.gov]

  Depending on where this happens, very serious clinical pictures can arise, such as an arterial gas embolism in the brain, which is similar to a stroke. [aqua-med.eu]

There are no specific tests for decompression sickness; it is purely a clinical diagnosis. Most times, the treatment itself is the test, if the person improves when treated with hyperbaric oxygen, it invariably proves that the person was suffering from decompression sickness. When the patient’s history suggests involvement of diving, determine if the patient is suffering from any pressure-related injuries. Get the basic lab tests done and if you feel there is some change in mental state of the patient or he/she is in shock, a more detailed workup is called for.

Following tests should be done in case of change in mental status:

• Blood glucose level, full blood count
• Sodium, magnesium, calcium, and phosphorous levels
• Blood oxygen saturation
• Ethanol level and drug screen
• Carboxyhemoglobin level

To rule out shock following tests should be performed:

• Blood glucose level, full blood count
• Electrolytes and BUN level
• Creatinine levels, lactic acid
• Blood type and screen/cross
• Prothrombin time, activated partial thromboplastin time
• Carboxyhemoglobin level

Imaging studies like chest radiography, head CT scan and MRI can be done to rule out any other injury caused due to diving leading to present set of symptoms.

Each and every case of decompression sickness should be treated with 100% oxygen initially till hyperbaric oxygen therapy is made available. Generally, the "bends" and skin symptoms disappear during the descent from high altitude, but still these cases should be thoroughly evaluated. Hyperbaric oxygen therapy should be used in treating neurological symptoms, pulmonary symptoms, and mottled or marbled skin lesions if they develop within 10-14 days. It is seen that the recovery is faster when the oxygen is given within the first four hours of surfacing. The recompression therapy is more successful due to prompt administration of oxygen and decreases the number of recompression treatments needed later [17]. Fluids help in reduction of dehydration. It is a general practice to give aspirin in case of diving accidents for antiplatelet activity, provided the patient is not bleeding, but there is no data to support this practice [18]. Aspirin can mask the symptoms, hence should not be given routinely unless indicated. Cardiopulmonary resuscitation should be done if needed and needle decompression of chest should be performed if there is suspicion of tension pneumothorax. The person should be made comfortable and made to lie in supine position, or the recovery position if vomiting occurs [2]. Do not place the patient in Trendelenburg position as it increases the intracranial pressure and worsens the injury to blood-brain barrier [19].

The duration of recompression treatment depends on the severity of symptoms, the dive history, the type of recompression therapy used and the patient's response to the treatment. Treat the patient for nausea, vomiting, headache and pain. The general protocol that is used for treatment includes providing hyperbaric oxygen therapy with a maximum pressure equivalent to 60 feet (18 m) of seawater for a total time under pressure of 288 minutes, of which 240 minutes are on oxygen and the balance are air breaks to minimize the possibility of oxygen toxicity [20].

Early diagnosis and prompt treatment play a vital role in prognosis of decompression sickness. Decompression sickness when treated immediately with 100% oxygen, followed by recompression in a hyperbaric chamber, will help in maximum recovery in most of the cases with no long-term effects. Occasionally, decompression sickness can also lead permanent long-term injury.

Decompression sickness occurs due to a rapid decrease in ambient pressure which leads to the formation of bubbles of inert gases within tissues of the body. It can take place when one leaves a high-pressure environment, ascending from depth, or ascending to altitude, during free or assisted dives. It is seen in people involved with tunneling projects, in submarines during emergencies, and in breath-hold free diving, one can see the effects of decreased pressure too.

The occurrence of decompression sickness is rare. Studies suggest that around 2.8 cases per 10,000 dives suffer from decompression sickness. It is also seen that males are at 2.6 times greater risk than females. Approximately 1,000 US scuba divers are affected by decompression sickness per year [2]. Because of variability in reporting and collecting information, it is not easy to pen the exact statistics of diving-related injury in any mainstream medical journal publication. In order to improve the collection of this data, the divers alert network (DAN), based in North Carolina in the United States, functions as a center for medical information and referral service in case of diving-related injuries. The Divers Alert Network (DAN) formed "Project Dive Exploration" in 1999 so as to gather data on dive profiles and incidents. Between 1998 and 2002, 50,150 dives were recorded, of which 28 needed re-compressions. These included the incidences of arterial gas embolism (AGE) which were at the rate of about 0.05% [3] [4]. According to DAN, less than 1% of divers experience decompression sickness [5]. With changes in law and medical confidentiality becoming more stringent, it has become difficult to obtain these reports and much more difficult to follow them up in United States [6].

Generally, divers suffer from decompression sickness as they have breathed gas which is at higher pressure than the surface pressure because of the pressure of the surrounding water. There are two main factors that control the chances of diver suffering from decompression sickness, namely, the rate and duration of gas absorption under pressure and the rate and duration of outgassing on depressurization. The first parameter means that deeper or longer the dive, the more gas is absorbed into body tissues in higher concentrations than normal. The second parameter means that faster the ascent and shorter the interval between dives, the less time there is for absorbed gas to be offloaded safely through the lungs; the outcome being that these gases come out of solution too rapidly and form "microbubbles" in the blood.

When these gas bubbles are trapped in any of the organs, it is very uncomfortable, irrespective of their sizes. This holds true even for highly trained divers. The bubbles cause different reactions depending on their location. For example if a small bubble reaches the lungs, it can be simply filtered and exhaled, but if there is a right to left shunt, which is seen in case of a patent foramen ovale, then the bubbles bypass the natural filtering effect of the lungs and can reach the brain or other organs and could be fatal. It is believed that the nitrogen bubbles start as minute gas nuclei, present before the dive, and are not formed from supersaturation of the blood and tissues which are the foundation of large bubble formation [7]. All divers have bubbles [8], but only few of them suffer from decompression sickness. The probability of decompression sickness does not increase merely due to the presence of bubbles [9].

Microbubbles come into play before the formation of larger venous gas emboli [10]. These emboli can block the flow of blood in tiny blood vessels leading to infarcts. It is found that the dives and decompression stress increases the formation of microparticles from the vascular walls about 3.4 times and seem to trigger neutrophils along with their interaction with platelet membranes [8] [11]. The release of platelet microparticles specifically, can reflect the bubble-induced platelet aggregation. It can be the reason for coagulation and thrombosis, thereby interfering with blood flow [12]. As soon as the bubbles form, a foreign body interface is created to which platelets attach themselves [13]. Marked reduction in platelet count has been documented in case of severe decompression sickness. This depletion in platelet count can be used as a marker to determine the severity of injury [14] [15].

The most important measure that can be taken to prevent decompression sickness is always giving personal safety top most priority. Despite of taking all the safety measures, there are cases of decompression sickness. Following are the measures to be taken to minimize the chances of suffering:

• Breathing 100% FIO2 oxygen during the decompression stops may help prevent decompression sickness [21].
• Being active during the decompression stops may also decrease the likelihood of bubble formation [22] [23] [24].
• It is advisable to keep yourself hydrated before and after the dive as it has protective effects.
• The partial pressure of oxygen should be considered at the decompression stop depth in order to prevent toxicity.
• Always keep in mind to ascend slowly to prevent decompression sickness. The time for ascent has been increased for a 60-ft dive from 1 minute to a maximum of 7 minutes. It is advised to stop ascent at decompression stops to allow the exhalation of nitrogen gas, rather than it’s bubbling in the blood.
• Aerobic exercise has proved to have positive effects on human beings as it increases the uptake of oxygen. The most important thing is the timing of this exercise prior to the diving. Maximum benefits were seen when these exercises were done for 40 minutes at 20 hours and 24 hours, respectively, before the dive. It was found that it had marked long-lasting effects on the number and size of nitrogen bubble formation [25] [26] [27] [28].
• Breathing normobaric oxygen for 30 minutes prior to the dive decreases venous bubble formation for the subsequent dive and repetitive dives afterwards with no further pre breathing [29] [30].
• Studies show that antioxidants help in maintaining normal hemostasis, and prevent inflammatory responses that can help to stop the decompression sickness process from starting [31].

Decompression sickness, also known as Diver’s sickness, is a complex condition caused due to change in barometric pressure. It is generally an outcome of underwater diving, high altitude or aerospace related events [1]. This condition arises due to dissolved gases escaping the blood as bubbles inside the body when depressurized too rapidly.

Decompression sickness is generally seen when a person is exposed to sudden change in barometric pressure. It is commonly experienced by divers and people working in aerospace or high altitude related professions. Due to sudden change in pressure, the gases dissolved in the body form bubbles and when these bubbles get trapped they produce various signs and symptoms. Depending on the site of entrapment, the person presents with different cutaneous, neurological, pulmonary or musculoskeletal symptoms. There are various measures that can be taken to prevent this condition and if treated promptly the person can recover completely. It is best to follow the safety protocols so as to avoid this condition as far as possible. It is not a guarantee that you won’t suffer from decompression sickness even after taking all necessary precautions. One can make sure that you have all knowledge about it, including the first aid so as to avoid any long term damages. The diagnosis is purely clinical and improvement with recompression therapy is the only real confirmatory test.

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