Evidence of a centrally mediated anti-inflammatory or direct anti-nociceptive effect of hyperbaric oxygen following a standard experimental thermal burn model

Clinical Bottom Line:

1. HBO reduced the area of secondary hyperalgesic response in this burn model

2. There was no difference shown in the area of primary hyperalgesia

3. Combined, these findings suggest the action of HBO is centrally mediated and may be anti-nociceptive or anti-infammatory.

Citation/s:1. Rasmussen VM, Borgen AE, Jansen EC, Rotbøll Nielsen PH, Werner MU. Hyperbaric oxygen therapy attenuates central sensitization induced by a thermal injury in humans. Acta Anaesthesiologica Scandinavica. 2015 Jul 1;59(6):749-62

Lead author's name:Per Rotboll Nielsen E-mail: per.rotboll.nielsen@regionh.dk

Three-part Clinical Question:For volunteers subjected to a thermal injury model, does a hyperbaric oxygen exposure, compared to no specific intervention, result in any evidence of an anti-nociceptive action?

Search Terms:Thermal burn; volunteer; nociception

The Study:Non-blinded randomised cross-over trial with intention-to-treat.

The Study Patients:Adult healthy male volunteers recruited from those previously volunteering for a thermal injury studies.

Control group(N = 19; 17 analysed): Thermal injury to calf area by application of a probe at 47C, immediately followed by observation in a 1ATA air environment

Experimental group(N = 19; 17 analysed): As above but injury followed immediately by one 90 minute session breathing 100% oxygen at 2.4 ATA

The Evidence:


Control Group

HBO Group



95% CI



Area under curve of secondary hyperalgesia per min (cm2) over 237 minutes


31.1 to 71.4


22.9 to 39.8


Area under curve of secondary hyperalgesia per min (mN) over 237 minutes


55 to 209


101 to 226




1. Warm detection threshold, cool threshold and heat pain thresholds were not different between groups

2. There was a statistically evident reduction in secondary hyperalgesia in the control group who had previously had the HBO exposure. (A crossover effect).

3. There is a possibility of bias due to the lack of blinding.

Appraised by:Mike Bennett Friday, 18 January 2019 Email: [m.bennett@unsw.edu.au]

Kill or Update By:December 2024