Table 1 Physiological aspects of hyperbaric oxygen therapy (HBOT)

Definition [12]

Treatment of a disease or medical condition by the inhalation of near-100% medical grade oxygen at pressures greater than 1 ATA

Physiology [6, 12, 13]

To enrich plasma with oxygen, maximizing tissue oxygenation. As the oxygen is in solution, it can reach physically obstructed areas and can also enable tissue oxygenation even with impaired haemoglobin oxygen carriage (such as in carbon monoxide poisoning and severe anaemia).

Indications [7, 12, 13]

♣ Air or gas embolism

♣ Carbon monoxide poisoning; cyanide poisoning; smoke inhalation

♣ Clostridial myostitis and myonecrosis (gas gangrene)

♣ Compartment syndromes and other acute traumatic peripheral ischaemia

♣ Decompression sickness

♣ Exceptional blood loss anaemia

♣ Intracranial abscess

♣ Refractory osteomyelitis

♣ Delayed radiation injury (soft tissue and bony necrosis)

♣ Thermal burns

Physiological pressure/oxygen correlation according to Sahni et al. [14]

Total pressure

Content of oxygen dissolved in

blood plasma (vol%)

ATA

mmHg

Breathing Air

100% Oxygen

1

760

0.32

2.09

normal atmospheric pressure

2

1520

0.81

4.44

pressure during HBOT

2.5

1900

1.06

5.62

3

2280

1.31

6.8

> 3

only applied when oxygen fraction is reduced because of risk of oxygen toxicity

Adapted treatment protocol (according to U.S. Navy Treatment [15])

Monoplace (single person): Compression rate 18 kPa/min to 180 kPa, air filled (21%) chamber for approximately 105 min. Afterwards decompression rate 9 kPa/min to 90 kPa for 170 min in oxygen filled (100%) chamber. Decompression rate 9 kPa/min to ambient pressure. Total treatment time: 275 min.

Multiplace: Compression rate 18 kPa/min to 180 kPa for 75 min. Afterwards decompression rate 3 kPa/min to 90 kPa for 150 min. Decompression rate 9 kPa/min to ambient pressure. Oxygen breathing is interspersed (every 30 min) with short periods of air breathing (5 min) to lower risk of oxygen toxicity. Total treatment time: 295 min.

Decompression rate in case of CPR

According to possibility to perform high-quality CPR: If possible, consider protocol-based decompression. If CPR is not possible, consider maximum decompression rate (technically according to type of pressure chamber). Recommendation of UHMS (12): Ability to decompress a Class B monoplace chamber from 3 ATA to surface in less than 2 min. Start CPR as soon as possible and safe.