Dr. Marco Ha · author and medical reviewer
Paediatric surgery, trauma surgery, hyperbaric and diving medicine · Last medically reviewed
Direct answer
Hyperbaric Oxygen and Diving Medicine: Decompression Illness and Warning Signs
What hyperbaric oxygen therapy is used for, symptoms of decompression illness and when post-dive pain, numbness, weakness or breathing difficulty needs emergency care.
The full guide below explains assessment, options and warning signs. Online information cannot replace an examination.
What is hyperbaric oxygen therapy?
Patients breathe high-concentration oxygen in a chamber at pressure above normal atmosphere. It is not a universal treatment and requires assessment of indication, timing, risk and the patient’s condition.
Conditions that may be assessed
Common referrals include decompression illness, carbon monoxide poisoning, selected ischemic or infected wounds and other guideline-supported indications.
What to do after concerning post-dive symptoms
Joint or muscle pain, skin changes, dizziness, numbness, weakness, breathing difficulty, unsteady walking or altered consciousness after diving should stop further diving and prompt professional evaluation. Do not use self-directed in-water recompression.
What is reviewed before treatment?
Ear pressure equalization, lung condition, medications, pregnancy possibility and other contraindications or risks are assessed. The number of sessions depends on the condition and response.
Key points
When assessing “Hyperbaric Oxygen and Diving Medicine: Decompression Illness and Warning Signs,” the decision should not be based on one photograph, one symptom or a single test result.
Hyperbaric oxygen is a medical treatment in a pressurized chamber, not a wellness oxygen service. Neurologic symptoms, severe vertigo, breathing difficulty or unusual profound fatigue after diving require oxygen and emergency or hyperbaric consultation.
Why does it happen and what is the natural course?
Post-dive symptoms can result from decompression illness, arterial gas embolism, ear, sinus or pulmonary barotrauma, motion sickness, dehydration, hypoglycemia or an unrelated neurologic or cardiovascular disorder. Timing, depth, ascent rate, omitted decompression, flying or altitude exposure and symptoms in a buddy are important clues. The absence of classic joint pain does not exclude decompression illness.
Understanding the natural course of when decompression illness requires emergency and hyperbaric evaluation helps avoid two opposite mistakes: treating a normal developmental variation too aggressively, or delaying care because someone said children always grow out of it.
How is it evaluated in clinic?
Assessment includes a full dive profile, neurologic examination, ear, sinus and lung examination, vital signs and oxygen saturation. Chest imaging, ECG, laboratory tests or specialist ear assessment may be added. Decompression illness is primarily a clinical diagnosis, and oxygen or transfer should not be delayed while waiting for every test.
When is observation reasonable and when is treatment needed?
Stop diving, provide high-concentration oxygen, rest supine, avoid exertion and contact emergency or diving-medicine services. Hyperbaric oxygen is considered according to symptoms, neurologic findings and exposure history. Do not re-enter the water for improvised recompression and do not fly to a distant hospital without medical advice.
What would we risk by observing? Is there a nonoperative option?
Home care and preparation for the visit
Reasonable hydration, avoiding alcohol and excessive fatigue, following computer and training limits, and checking emergency oxygen and contact plans with a buddy reduce risk. If symptoms occur, preserve the dive-computer profile, gas information and a written timeline for the medical team.
Red flags that should not wait
Common myths and avoidable mistakes
In-water recompression without a trained medical system is hazardous and should not replace formal hyperbaric care.
Follow-up: how do we know the plan is working?
Return to diving after hyperbaric treatment depends on the diagnosis, residual symptoms, contributing factors and specialist review. Complete symptom resolution does not always mean immediate fitness to dive, especially after inner-ear or neurologic involvement.
Frequently asked questions
Can hyperbaric oxygen be used for general wellness or anti-aging?
Medical hyperbaric oxygen should be based on accepted indications and an individualized risk-benefit assessment.
Should a diver return underwater to complete decompression after a rapid ascent?
Do not attempt in-water recompression without an organized professional protocol. Review the dive profile and seek urgent care if symptoms occur.
Medical review and references
Reviewed against the following professional sources. Individual care still requires clinical assessment.
How sources are selected, reviewed and corrected: medical editorial and source policy.
Pediatric surgery, trauma surgery and hyperbaric medicine. Last updated: August 6, 2026.