Hyperbaric chambers Hyperbaric medicine

multiplace hyperbaric chambers, showing control panel, monitoring facilities, , different chamber sizes in spanish facilities


construction

the traditional type of hyperbaric chamber used therapeutic recompression , hbot rigid shelled pressure vessel. such chambers can run @ absolute pressures typically 6 bars (87 psi), 600,000 pa or more in special cases. navies, professional diving organizations, hospitals, , dedicated recompression facilities typically operate these. range in size semi-portable, one-patient units room-sized units can treat 8 or more patients. larger units may rated lower pressures if not intended treatment of diving injuries.

a rigid chamber may consist of:

a pressure vessel made of steel or aluminium view ports (windows) made of acrylic;
one or more human entry hatches—small , circular or wheel-in type hatches patients on gurneys;
the entry lock allows human entry—a separate chamber 2 hatches, 1 outside , 1 main chamber, can independently pressurized allow patients enter or exit main chamber while still pressurized.
a low volume medical or service airlock medicines, instruments, , food;
transparent ports or closed-circuit television allows technicians , medical staff outside chamber monitor patient inside chamber;
an intercom system allowing two-way communication;
an optional carbon dioxide scrubber—consisting of fan passes gas inside chamber through soda lime canister;
a control panel outside chamber open , close valves control air flow , chamber, , regulate oxygen hoods or masks;
an over-pressure relief valve.
a built-in breathing system (bibs) supply , exhaust treatment gas.
a fire suppression system.

flexible monoplace chambers available ranging collapsible flexible aramid fiber-reinforced chambers can disassembled transport via truck or suv, maximum working pressure of 2 bar above ambient complete bibs allowing full oxygen treatment schedules. portable, air inflated soft chambers can operate @ between 0.3 , 0.5 bars (4.4 , 7.3 psi) above atmospheric pressure no supplemental oxygen, , longitudinal zipper closure.

hard chambers , soft chambers not equivalent in efficacy , safety different in many aspects.

oxygen supply

a recompression chamber single diving casualty

in larger multiplace chambers, patients inside chamber breathe either oxygen hoods – flexible, transparent soft plastic hoods seal around neck similar space suit helmet – or tightly fitting oxygen masks, supply pure oxygen , may designed directly exhaust exhaled gas chamber. during treatment patients breathe 100% oxygen of time maximise effectiveness of treatment, have periodic air breaks during breathe chamber air (21% oxygen) reduce risk of oxygen toxicity. exhaled treatment gas must removed chamber prevent buildup of oxygen, present fire risk. attendants may breathe oxygen of time reduce risk of decompression sickness when leave chamber. pressure inside chamber increased opening valves allowing high-pressure air enter storage cylinders, filled air compressor. chamber air oxygen content kept between 19% , 23% control fire risk (us navy maximum 25%). if chamber not have scrubber system remove carbon dioxide chamber gas, chamber must isobarically ventilated keep co2 within acceptable limits.

a soft chamber may pressurised directly compressor. or storage cylinders.

smaller monoplace chambers can accommodate patient, , no medical staff can enter. chamber may pressurised pure oxygen or compressed air. if pure oxygen used, no oxygen breathing mask or helmet needed, cost of using pure oxygen higher of using compressed air. if compressed air used, oxygen mask or hood needed in multiplace chamber. monoplace chambers can fitted demand breathing system air breaks. in low pressure soft chambers, treatment schedules may not require air breaks, because risk of oxygen toxicity low due lower oxygen partial pressures used (usually 1.3 ata), , short duration of treatment.

for alert, cooperative patients, air breaks provided mask more effective changing chamber gas because provide quicker gas change , more reliable gas composition both during break , treatment periods.