Portable Hyperbaric Chambers

[DiveTheGalapagos]

Thanks everyone. You have confirmed what I suspected...oxygen concentrators will be the way to go. Glad to know about the SOS Hyperlite.

 

[Dr Deco]

Hello readers:

Regrettably, the situation where one really needs a hyperbaric chamber is for an arterial gas embolism. These result from rapid ascents such as panic attacks with breath holding. There are many scenarios - most bad.

Laboratory tests indicate that pressures equal to about 100 fsw are required to cause the gas embolus to shrink and pass through the capillaries [of the brain or spinal cord] and move to the venous side of the circulation.

Portable chambers today do not allow for such high pressures. It is questionable how clinically useful they might be. Certainly, the ability to provide food and water for an extended duration is important. Monitoring blood pressure and pulse rate is important although without medical assistance little might be done anyway. Removal of waste from the patient is also necessary.

When I was with NASA, we looked at this problem and decided that return from orbit to Earth was best. In addition was the problem of storage of equipment and the training of the outside operators. Loss of ability and skill with time was considered to be a factor.

Dr Deco :doctor:

 

[Gene_Hobbs]

Below is a list of publications I pulled together a while back for a Government agency that was working on a justification for the purchase of oxygen concentration equipment and a portable chamber, you might find them interesting:

Wells JM, Dinsmore DA. Evaluation of Atmospheric Oxygen Concentrators as a Source of Oxygen and Oxygen Rich Mixtures for Treatment of Diving Accident Victims in Remote Areas. In: Brueggeman P, Pollock NW, eds. Diving for Science 2008. Proceedings of the American Academy of Underwater Sciences 27th Symposium. Dauphin Island, AL: AAUS; 2008. RRR ID: 8023

Potkin R, Wells JM. Feasibility of In Water Recompression for Precautionary and Treatment of Decompression Illness in Remote Locations. In: Brueggeman P, Pollock NW, eds. Diving for Science 2008. Proceedings of the American Academy of Underwater Sciences 27th Symposium. Dauphin Island, AL: AAUS; 2008. RRR ID: 8016 (Additional reading on IWR can be found here)

Krock, Galloway, Sylvester, Latson, Wolf Jr. Into the Theater of Operations: Hyperbaric Oxygen on the Move. Presented at the NATO "Operational Medical Issues in Hypo- and Hyperbaric Conditions" Meeting in 2000. RRR ID: 5496

Other papers on the evaluation of this system are below if you need them for any future proposals.

Wright and Krock. 2002. AIR FORCE DEPLOYMENT OF THE EMERGENCY EVACUATION HYPERBARIC STRETCHER. UHMS Abstract. RRR ID: 1087

Sylvester, Krock, and Eshelman. 2000. Testing and Evaluation of the SOS, Ltd., Hyperlite, Emergency Evaluation Hyperbaric Stretcher, Model 24/88/SAT/70. USAF - Brooks AFRL-HE-BR-TR-2001-0069 RRR ID: 4981

Latson and Zinszer. 1999. Evaluation of Emergency Evacuation Hyperbaric Stretchers (EEHS). NEDU-TR-5-99 on project NAVSEA-TA-97-022. RRR ID: 3574

Latson and Flynn. 1999. Use of Emergency Evacuation Hyperbaric Stretcher (EEHS) in Submarine Escape and Rescue. NEDU-TR-4-99. RRR ID: 3563



An additional text that is well worth the time to look over is the DAN sponsored workshop on remote locations:

Mitchell SJ, Doolette DJ, Wachholz CJ, Vann RD (eds.). 2005. Management of Mild or Marginal Decompression Illness in Remote Locations Workshop Proceedings. Durham NC: Divers Alert Network. 240 pages. RRR ID: 5523

 

[Bubbletrubble]

Laboratory tests indicate that pressures equal to about 100 fsw are required to cause the gas embolus to shrink and pass through the capillaries [of the brain or spinal cord] and move to the venous side of the circulation.

@Dr Deco: In the past, pressurizing to 100 fsw was recommended protocol in the setting of cerebral AGE. However, I was under the impression that the prevailing notion nowadays is that the benefit of doing this versus pressurizing to only 60 fsw is inconclusive. In fact, I think that the standard recommendation now is to initially treat with oxygen using a US Navy Table 6 treatment and then, if clinical results are judged to be suboptimal, to consider deeper recompression or extension of the treatment table.

I think you're discounting the potential clinical utility of these portable hyperbaric chambers. In an emergent situation with the appropriate expertise on-hand, I think they could be very helpful. And, in case you were wondering, the SOS Hyperlite does allow IV access, a ventilator option, and other types of physiological monitoring.

 

[Wayan]

Hello readers:

Regrettably, the situation where one really needs a hyperbaric chamber is for an arterial gas embolism. These result from rapid ascents such as panic attacks with breath holding. There are many scenarios - most bad.

Laboratory tests indicate that pressures equal to about 100 fsw are required to cause the gas embolus to shrink and pass through the capillaries [of the brain or spinal cord] and move to the venous side of the circulation.

Portable chambers today do not allow for such high pressures. It is questionable how clinically useful they might be. Certainly, the ability to provide food and water for an extended duration is important. Monitoring blood pressure and pulse rate is important although without medical assistance little might be done anyway. Removal of waste from the patient is also necessary.

When I was with NASA, we looked at this problem and decided that return from orbit to Earth was best. In addition was the problem of storage of equipment and the training of the outside operators. Loss of ability and skill with time was considered to be a factor.

Dr Deco :doctor:

Doc The Hytech Dart has a WP of 5.5 bar and could be used for the start some of the Deep re-compression tables whilst transferring to a TUP (Transfer Under Pressure) capable Hyperbaric unit. It seems that it is preferred if a COMEX 30 table used for these type case if necessary. The trouble being most centres do not have COMEX capabilities as the cost is extraordinary high for the limited no of times that it is used.

Certainly would not want to be the Tender inside as these duocom units are very small and cramped and for some people quite claustrophobic.

As you say it is important to be able to physically monitor the progress of the patient, extremely difficult to do in a lot of circumstances even if talking to them over an intercom in the same room.

 

[Wayan]

@Dr Deco: In the past, pressurizing to 100 fsw was recommended protocol in the setting of cerebral AGE. However, I was under the impression that the prevailing notion nowadays is that the benefit of doing this versus pressurizing to only 60 fsw is inconclusive. In fact, I think that the standard recommendation now is to initially treat with oxygen using a US Navy Table 6 treatment and then, if clinical results are judged to be suboptimal, to consider deeper recompression or extension of the treatment table.

I think you're discounting the potential clinical utility of these portable hyperbaric chambers. In an emergent situation with the appropriate expertise on-hand, I think they could be very helpful. And, in case you were wondering, the SOS Hyperlite does allow IV access, a ventilator option, and other types of physiological monitoring.

Understand what you saying, however, we need to be cognisant of the fact that this is an prescribed medical treatment and not a decision to be made by lay people.

Now I am not saying it is impossible but the operator if they decide to have one on-board or at a remote location would need to have appropriately trained operators and medics and have a 24 hour qualified Hyperbaric Medical Doctor Support which is what a lot of the commercial diving rigs will do. (this is not cheap in itself). Then they would need to think about indemnity insurance and the likes.

You are correct that it is general accepted protocol international to start the initial treatment with an USN TT6, it thne becomes a medical decision depending on the capabilities of the unit and the needs of the patient as to whether the table is converted into a COMEX 30 or USN TT6A (COMEX 30 is preferred)

 

[Bubbletrubble]

Understand what you saying, however, we need to be cognisant of the fact that this is an prescribed medical treatment and not a decision to be made by lay people.

I agree. I was thinking that products like the SOS Hyperlite would be useful for helicopter evac, military missions, commercial diving ops and possibly marine science expeditions. I seriously doubt that a recreational liveaboard would ever go to the trouble and expense of having such an item on-board and paying for trained personnel to operate the device. Many live-aboards feature a hot tub that is broken for one reason or another. If they can't keep a hot tub working, how can I trust them to make sure that a portable hyperbaric chamber is in tip-top shape?

Thank you for the information regarding hyperbaric treatment protocols for AGE.

 

[Wayan]

I agree. I was thinking that products like the SOS Hyperlite would be useful for helicopter evac, military missions, commercial diving ops and possibly marine science expeditions. I seriously doubt that a recreational liveaboard would ever go to the trouble and expense of having such an item on-board and paying for trained personnel to operate the device. Many live-aboards feature a hot tub that is broken for one reason or another. If they can't keep a hot tub working, how can I trust them to make sure that a portable hyperbaric chamber is in tip-top shape?

Thank you for the information regarding hyperbaric treatment protocols for AGE.

Sure depending on the Helicopter both the DUOCOM and HYTECH DART might be able to be used for these. Normally they are used in fixed wing A/C. With the Helicopter option I would expect that the range of these would be reduced with the extra weight.

The biggest problem I see with it is that it does not appear to have TUP facility so the patient would need to remain inside this until completion of the TT6 (nearly 5 hours).

 

[Bubbletrubble]

Sure depending on the Helicopter both the DUOCOM and HYTECH DART might be able to be used for these. Normally they are used in fixed wing A/C. With the Helicopter option I would expect that the range of these would be reduced with the extra weight.

The SOS Hyperlite weighs 110 lbs. I think the DUOCOM and HYTECH DART are substantially heavier. Can you confirm this?

The biggest problem I see with it is that it does not appear to have TUP facility so the patient would need to remain inside this until completion of the TT6 (nearly 5 hours).

I don't know how much it costs to upgrade a hyperbaric facility so that it is TUP-capable. It probably isn't cheap. Since the use of portable hyperbaric chambers isn't very common at present, the demand for TUP facilities is very low. If their use does become more popular, then perhaps hyperbaric facilities will consider investing in the necessary upgrades.

Depending on how emergent the situation is, one option would be to allow the patient to finish up the TT6 in the portable chamber and then standby at the hyperbaric facility for further treatment.

Another option would be to conduct a shorter recompression protocol (TT5?) while the patient is in-transit. One obstacle to this approach is that probably very little research exists on the effectiveness of treating first with TT5 and then subsequently with more aggressive recompression schedules. Just a few thoughts...

 

[hyperbaricjosh]

Well I see some folks are for the Hyperlite some others are not. We in Quebec Canada commonly dive in remote areas where the nearest hyperbaric chamber is 6 to 7 hours away. We opted to buy these wounderful unit call the Hyperlite. Built to last an easy to use. No wounder why the US Navy and US Coast Guard are using them. Plus they went through the most extensive testing in the world in order to get the US Navy approval which the GSI didn't get. We bought one unit and installed it in a remote area called Les Escoumins where about 2500 to 3000 divers visit a year. We are in the process of installing another one in another remote area of Quebec. The have currently many protocoles in place for transfering patient wether under pressure or surface transfer. Helicopter transfer or ambulance transfer. My military training and Diving medicine training was always to put the patient (diver) under pressure asap (1 hour) in order to reduce any sequelea of the DCS. Press to 3 ATA and reassess the patient. Those units will not only permit such treatment it is transferable to the nearest HBO facility under pressure and at altitude if required. For the price it is worth it sinc the life of someone is priceless. I strongly recommend a Hyperlite for your need. If you want more info email me and I'll gladly give more info on it.