Hyperbaric Oxygen Therapy - Patient Frequently Asked Questions

How does the HBO work?

Hyperbaric oxygen works through a combination of increased ambient pressure and oxygen concentrations.  Please click below for a more complete discussion of this topic.

Mechanism of Action

What Happens when I come in for a consult?

Of course, each patient's experience will be somewhat different, but in general, the following events will occur:

  • You will be seen by the hyperbaric physician who will perform a history and physical.  He or she will determine if hyperbaric treatments are appropriate for you, order any necessary tests, and will discuss the treatment options. 

  •  You will speak with a respiratory therapist who will discuss in detail the sequence of events during a dive, discuss the scheduling of treatments, and review applicable risks and safety precautions.

  • If you are being seen because of a chronic wound, pictures will be taken to help judge the progress of treatments and a Trans-Cutaneous Oxygen Measurement (TCOM) test may be performed.

Are Hyperbaric treatments covered by insurance?

Yes. The Undersea and Hyperbaric Medicine Society has recommended hyperbaric oxygen treatments for several disease states. Medicare and private insurers , to a greater or lesser degree, have accepted these recommendations and will pay for HBO treatments for these indications. However, if there are any questions about insurance coverage, our billing staff can look into the matter and confirm coverage prior to starting treatments.

What happens during a treatment?

There are several stages during a typical treatment (or dive).  The first stage is compression (or diving) in which the chamber is pressurized to the prescribed pressure (or depth), most commonly 2.4 atmospheres absolute (the equivalent of 45 feet below the surface of the ocean, i.e. 45 feet of sea water).  The chamber is maintained at this pressure (depth) and the patients breathe 100% oxygen via a hood.  Patients are given two “air breaks” during this oxygen-breathing period where they can take off the hood to get a drink of water, etc.  After the oxygen periods are finished, the chamber is depressurized (or surfaced) and the treatment is finished.

How long does a treatment last, how many treatments will I need, and how often?

A typical treatment generally lasts a bit over two hours:

Of course, treatments can sometime take longer, especially if patients have difficulty clearing their ears during the pressurization phase.

The number and frequency of treatments needed varies with the specific condition that is being treated.  However, for most conditions, one treatment a day (Monday-Friday) is given for a total of 20-30 treatments (i.e. 4-6 weeks total).

Pressurizing the chamber 7-10 minutes
First oxygen period  30 minutes
First air break  10 minutes
Second oxygen period  30 minutes
Second air break 10 minutes
Third oxygen period  30 minutes
De-pressurization   7-10 minutes
Total time 124-130 minutes

What will I feel during a treatment, will it hurt?

Once inside the chamber, the patient will hear the air beginning to circulate. Patients are able to see and talk with the chamber staff member, who will tell them when the gradual increase in pressure has begun. This is called compression.  The feeling is similar to landing in an airplane. 

When the prescribed pressure is reached, patients are asked to place a hood or mask over their heads in order to receive 100% oxygen while in the chamber. The attendant will assist with this. The hood is clear plastic which will allow unobstructed vision.  At this point, no further pressure sensation are typically felt.

Near the end of the treatment, the staff will gradually decrease the chamber pressure. This is the decompression phase, which usually lasts for about 7 minutes. During decompression, patients will experience an automatic "popping" sensation in the ears as a result of the decreasing pressure. This may be similar to what is felt in an airplane on takeoff.

Hyperbaric treatment is painless, but patients may have the sensation of a fullness in the ears, similar to what is experienced when driving up or down a mountain road, changing altitudes in an airplane, or changing depths in underwater diving. The feeling of fullness occurs as the eardrums respond to the changes in atmospheric pressure.

What is meant by "clearing my ears", how do I do it, and what happens if I can't?

Clearing the ears” is a term that is used to indicate actively equalizing the pressure across the eardrum (i.e. making the pressure in the middle ear behind the eardrum equal to the outside pressure). 

There are several techniques that can be used.  They range from simply yawning or swallowing to closing the mouth and pinching the nose while blowing out/bearing down (a procedure known a valsalva maneuver).  Our attendants work very closely with new patients during their first few dives until the patient finds the method that works best. 

If the ears are not cleared, the build-up of pressure can eventually lead to pain, hearing damage, and even ruptured ear drums.  If patients absolutely cannot clear their ears, they are sent to the Otolaryngology (ENT) department for the placement of myringotomy tubes, which are small tubes placed directly into the ear drum that allow air to pass freely in and out of the middle ear.

What do patients wear a hood during treatments?

During hyperbaric oxygen treatment, patients need to breathe 100% oxygen.  However, due to fire safety concerns, the amount of oxygen in the air in the chamber itself must be kept to a minimum.  Therefore, patients wear a hood which is designed to have oxygen pumped into it and then exhausted outside the chamber.

Are there any risks or side-effects associated with HBO?

As with any medical treatment, there are possible risks and side-effects with hyperbaric oxygen therapy.  Most are mild and self-limited, but some can be severe.  Please click below for a more thorough discussion.

Risks and Side Effects of HBO

What should I do to prepare for a treatment?

As with any medical treatment, there are possible risks and side-effects with hyperbaric oxygen therapy.  Most are mild and self-limited, but some can be severe.  Please click below for a more thorough discussion.

Risks and Side Effects of HBO

What can I do in the chamber during a treatment and what can I bring with me?

To help pass the time during a treatment, patients are allowed to do things such as read, write, do word puzzles, converse with other patients and staff, work on small handicrafts (such as needlepoint), even take a nap.

However, due to fire concerns in a hyperbaric environment, many items are not allowed in the chamber.

  • Personal electronic devices such as pagers, cell phones, PDA's, music players, handheld games, and laptop computers are not allowed.

  • Any item that may be a source of fuel or ignition, such as lighters, smoking materials, and hand warmers, are also proscribed.

  • Any make-up, hair spray, perfume, or shaving lotion containing a petroleum or alcohol base is not allowed during the treatment session.

  • Clothing: Patients are provided with a 100% cotton scrub suit to wear during treatment. No articles, including undergarments, containing nylon or polyester are to be worn in the chamber.

  • Watches and prosthetic devices should be removed before treatment.

Prior to their first treatment, patients will given a list of allowed and non-allowed items.  Of course, this list cannot be all-inclusive and unique situations will be judged on a case-by-case basis.

What if I am Claustrophobic?

Due to the size of our chamber, even patients with claustrophobia are usually able to tolerate treatments without difficulty.  However, if necessary, sedation can be provided on a case-by-case basis after consultation with the medical staff.

Should I eat or drink before a treatment?

Definitely.  While drinks and snacks can be provided during a dive under certain circumstances, our ability to do so is significantly restricted.  In addition, we have found that patients, especially those with diabetes, tolerate treatments better if they are well hydrated and have had something to eat prior to the treatment.  However, please bear in mind that restroom options are extremely limited during the two-hour treatment, so excess fluid intake should be avoided.

How does HBO effect diabetes?

Strict glucose control is an integral part of wound care.  Thus, patients are encouraged to work closely with the physician that is caring for their diabetes to maintain optimal blood glucose levels.  We encourage patients to continue with their normal insulin and nutrition regimens during their HBO treatments.  However, some patients with diabetes will experience a decrease in blood sugar during a dive.  Thus, blood glucose monitoring is performed in the chamber during dives to assure that the patient's blood sugar does not get too low.  In some circumstances, adjustments in a patient's insulin regimen may need to be made.

Are there any restroom facilities in the chamber?

No.  While there is a bathroom in the hyperbaric medicine clinic area, there are no facilities within the chamber itself.  During a treatment, bedpans and urinals are available, but privacy cannot be guaranteed. Therefore, patients are encouraged to use the facilities before entering the chamber.

Will those be anyone else int he chamber with me?

Yes. There is always an attendant inside the chamber with the patients during the entire dive.  Attendants may switch out during the dive, but one remains in the treatment chamber at all times.  In addition, there will usually be multiple patients undergoing treatments at the same time, up to the maximum chamber capacity of six patients plus one inside attendant.

Why do you use nautical terms and what do they mean?

We use nautical terms in hyperbaric medicine because many of our techniques and procedures were originally developed by naval organizations in response to diving operations and these terms have persisted as these procedures have been adapted for hyperbaric medicine.  Some of these terms and their meanings are:

  • dive: a single HBO treatment

  • dive the chamber: pressurizing the chamber for a treatment

  • surface the chamber: depressurizing the chamber at the end of a treatment

  • at depth: the chamber is pressurized

  • at the surface: the chamber is depressurized, or at sea level pressure

  • feet of seawater: a measure of pressure that is equal to being submerged in one foot of seawater

What is a TCOM test and what does it show?

The Trans-Cutaneous Oxygen Measurement (TCOM) test is used to determine the level of oxygen in tissues.  During the test, sticky probes are placed around the wound and measure the level of oxygen in the tissues at baseline and then while breathing 100% oxygen at sea level.  Occasionally, these readings are also taken while the patient breaths 100% at depth.  Based on the results of these tests, we can determine whether HBO is likely to help with wound healing or not.