The Bends & Recompression
Hyperbaric Chamber Treatment for Decompression Sickness
Decompression sickness, or the bends, is a diving emergency treated by recompression in a hospital or dedicated dive chamber. If symptoms follow a dive, call 911 and the DAN emergency hotline. Generations Wellness is an outpatient center and does not provide emergency recompression.
This is a medical emergency. Call 911 or go to the nearest emergency room. If you or a dive buddy may have decompression sickness or another diving injury, also call the Divers Alert Network (DAN) emergency hotline at +1-919-684-9111, available 24/7. Breathe 100% oxygen if it is available and lie flat while you wait. Emergency recompression is delivered at hospital-based or dedicated dive chambers. Generations Wellness is an outpatient center in Modesto and does not provide emergency HBOT.
The Basics
What Decompression Sickness Is
When you breathe compressed air underwater, your body absorbs extra nitrogen. On the way back up, that nitrogen leaves your tissues. If you ascend too quickly, or stay too deep for too long, the nitrogen can form bubbles in your blood and tissues, much like bubbles appear when you open a bottle of soda. Those bubbles block blood flow, stretch tissue and trigger inflammation. That is decompression sickness (DCS), often called "the bends."
Two broad types
- Type I (milder forms): joint or limb pain, often in the shoulders or elbows; itching, rash or mottled skin; swelling from blocked lymph flow; unusual tiredness.
- Type II (serious forms): numbness, tingling or weakness; trouble walking or with balance; confusion; problems with bladder or bowel control; chest pain, cough or shortness of breath.
Mild symptoms can progress, so any symptom after a dive deserves a call to DAN or a doctor the same day.
When it starts
Most cases begin within a few hours of surfacing, and nearly all within 24 hours. Flying or driving to altitude soon after diving can bring on symptoms later.
What raises the risk
- Fast ascents or missed safety stops
- Deep, long or repeated dives, including multiple days of diving
- Flying or going to altitude too soon after diving
- Dehydration, heavy exertion, cold water and fatigue
- A patent foramen ovale (PFO), a small opening between the heart's upper chambers that some people have without knowing
The Mechanism
Why a Hyperbaric Chamber Is Used for Decompression Sickness
Recompression works in two ways at once.
Pressure shrinks bubbles. Gas takes up less space under pressure. This is Boyle's law. Raising the pressure around the body makes the nitrogen bubbles smaller, which can restore blood flow and ease pressure on nerves and tissue.
Oxygen pulls nitrogen out. Breathing close to 100% oxygen means there is almost no nitrogen in the lungs. That creates a steep gradient, so nitrogen leaves the bubbles and tissues faster. The extra oxygen also reaches tissue that has been starved of blood flow and helps limit swelling.
Pressure in a chamber is measured in atmospheres absolute. If that term is new, see what ATA means. For the bigger picture, read how pressure and oxygen act on gas bubbles. Decompression sickness is one of the FDA-cleared indications for hyperbaric chambers and is on the Undersea and Hyperbaric Medical Society (UHMS) indications list.
Treatment Tables
What Recompression Treatment Looks Like
The most widely used treatment is US Navy Treatment Table 6. It lasts about 4 hours and 45 minutes, and the team can extend it if symptoms have not resolved. It follows two main stages:
| Stage | Pressure | Breathing gas |
|---|---|---|
| Deep stage | 2.8 ATA (equal to 60 feet of seawater) | Periods of 100% oxygen with short air breaks |
| Shallower stage | About 1.9 ATA (equal to 30 feet of seawater) | Longer oxygen periods with air breaks |
| Total time | Slow return to surface pressure | About 285 minutes, longer if extended |
Treatment usually happens in a hospital multiplace chamber, where a trained attendant can sit inside with the patient, or in a dedicated recompression facility. Some divers need repeat treatments over several days if symptoms remain. Before arrival, first aid matters: 100% oxygen, lying flat, and fluids by mouth if the diver is fully awake and able to swallow.
Why an outpatient center is not a dive chamber
Emergency recompression can take many hours, may need to be extended without warning, and can require critical-care support for a seriously injured diver. Generations Wellness uses hard-shell monoplace (single-person) chambers for scheduled, physician-prescribed outpatient sessions. We are not set up for emergency recompression. For more on the difference, read why hospital chambers handle emergencies.
Near Modesto
Where Divers Are Treated Near Modesto
Divers should not search for a chamber and drive there on their own. Chamber availability changes from day to day, and a chamber listed online may not be staffed for emergencies.
- Call 911 or go to the nearest emergency department. Emergency physicians stabilize you and coordinate transfer to a hyperbaric facility when recompression is needed.
- Call DAN at +1-919-684-9111. DAN's 24/7 hotline connects you or your doctors with dive-medicine specialists who can help locate the nearest chamber that is staffed and available that day.
- Let the professionals arrange transport. Flying or driving over high mountain routes can make symptoms worse, so transport decisions belong to the medical team.
Honest Evidence
What the Evidence Shows
Recompression is the standard of care for decompression sickness. The evidence behind it is a different kind from most drug studies, and it is worth being clear about that.
| Source | Type of evidence | What it supports | Limitation |
|---|---|---|---|
| Naval and civilian treatment records | Decades of case series | Most divers improve with prompt recompression on standard tables | No placebo-controlled trials, because withholding recompression would be unethical |
| UHMS best practice guidelines | Expert consensus based on published data | Recompression with oxygen for DCS; first aid oxygen before arrival | Consensus guidance rather than randomized trial results |
| Retrospective analyses of delayed treatment | Observational studies | Many divers still benefit when recompression is delayed | Earlier treatment is still preferred; outcomes vary by severity |
No study can predict how any individual diver will recover. Serious neurological cases can leave lasting symptoms even with good treatment, which is one more reason to seek help quickly.
Follow-Up Care
After the Emergency: Residual Symptoms and Follow-Up
Many divers feel much better after their first treatment. Some have lingering numbness, weakness, fatigue or joint pain. Hospital hyperbaric programs may give more treatments over the following days while symptoms keep improving.
Follow-up after DCS usually includes:
- A check with the treating hyperbaric or dive-medicine physician before discharge
- Clear guidance on when it is safe to fly, drive to altitude or exercise hard
- Follow-up with your own doctor, and with a neurologist if nerve symptoms remain
- A fitness-to-dive evaluation before you dive again, sometimes including heart testing for a PFO
Return-to-diving and flying decisions are made by a dive-medicine physician. DAN can help you find one.
Generations Wellness
Our Outpatient Role, Honestly
Generations Wellness is a physician-directed outpatient center under Dr. Rajwinder Singh Bahia, MD. We do not provide emergency recompression, and we do not treat decompression sickness. If you have symptoms after diving, call 911 and DAN, not our office.
Your recovery plan after the emergency belongs with the hospital hyperbaric team and dive-medicine physicians who treated you. Once you are stable and home, our team is glad to talk with you and answer general questions about hyperbaric oxygen therapy. Physicians can find information for referring physicians, and you can see the conditions HBOT is cleared for. Arterial gas embolism, a related diving emergency, is covered on our page about arterial gas embolism and other hospital-only indications.
Dive Season
Prevention for Central Valley Divers
Divers from the Modesto area often travel to the coast or to mountain lakes. A few habits lower the risk of DCS on every trip:
- Ascend slowly and make safety stops. Follow your dive computer and stay well inside its limits.
- Wait before flying. DAN guidance is at least 12 hours after a single no-decompression dive and at least 18 hours after repetitive dives or multiple days of diving.
- Count the drive home. Driving over high mountain passes or up into the Sierra after diving is an altitude exposure, just like a flight. Plan your route and timing.
- Plan altitude dives properly. Lake Tahoe sits around 6,200 feet, so diving there calls for altitude-adjusted dive planning.
- Stay hydrated and rested, and avoid hard exercise right before and after diving.
Important
Generations Wellness does not provide emergency recompression. For a diving injury, call 911 and DAN at +1-919-684-9111. A physician assessment is required before beginning any HBOT at our center, and HBOT complements, and never replaces, the treatment prescribed by your doctors.
Questions
Decompression Sickness: Frequently Asked Questions
Is there a hyperbaric chamber for divers near Modesto?
Emergency recompression is arranged through 911 and the DAN hotline, which help direct you to the nearest staffed chamber. Outpatient centers like ours are not set up for emergency recompression.
How long is decompression sickness treatment?
A standard US Navy Table 6 lasts about 4 hours and 45 minutes at up to 2.8 ATA. It can be extended, and some divers need repeat sessions if symptoms persist.
Can decompression sickness start hours after a dive?
Yes. Most cases start within a few hours and nearly all within 24 hours, which is why any symptom after diving should be reported the same day.
Is the bends the same as an air embolism?
No. Arterial gas embolism comes from lung over-expansion and usually looks like a stroke within minutes of surfacing. Both are emergencies, and both are managed with recompression in a hospital or dive chamber.
Can I fly after treatment?
Only when the treating dive-medicine physician clears you. DAN can provide guidance on timing.
Sources
- Undersea and Hyperbaric Medical Society. UHMS Best Practice Guidelines: Prevention and Treatment of Decompression Sickness and Arterial Gas Embolism. uhms.org
- Divers Alert Network. Emergency Assistance. dan.org
- Centers for Disease Control and Prevention. CDC Yellow Book: Scuba Diving, Decompression Illness and Other Dive-Related Injuries. cdc.gov
- Naval Sea Systems Command. US Navy Diving Manual, Revision 7 (Treatment Table 6). navsea.navy.mil
- Undersea and Hyperbaric Medical Society. Hyperbaric Oxygen Therapy Indications. uhms.org
- U.S. Food and Drug Administration. Hyperbaric Oxygen Therapy: Get the Facts. fda.gov
This page is educational and not medical advice. For a diving injury, call 911 and DAN. Generations Wellness does not provide emergency hyperbaric treatment. See our full medical disclaimer, including emergency numbers.
If This Is an Emergency
Call 911 First
Emergency hyperbaric treatment happens in hospital settings. For follow-up questions once you are stable, our team is glad to talk.
Prefer to talk? (369) 222-0979