Hyperbaric oxygen for children with cerebral palsy: a randomised multicentre trial. HBO-CP Research Group.
Collet JP, Vanasse M, Marois P, Amar M, Goldberg J, Lambert J, Lassonde M, Hardy P, Fortin J, Tremblay SD, Montgomery D, Lacroix J, Robinson A, Majnemer A.

Randomised Clinical Trial Unit, Jewish General Hospital, Montreal, Quebec, Canada. jpcollet@epid.jgh.mcgill.ca

BACKGROUND: The use of hyperbaric oxygen for children with cerebral palsy has spread worldwide, despite little scientific evidence of efficacy. We did a randomised trial to assess the efficacy and side-effects of this form of therapy in children with cerebral palsy. METHODS: 111 children with cerebral palsy aged 3-12 years were randomly assigned hyperbaric oxygen (n=57) or slightly pressurised room air (n=54). All children received 40 treatments over 2 months. Hyperbaric oxygen treatment was 1 h in 100% oxygen at 1.75 atmospheres absolute (ATA); children on slightly pressurised air received air at 1.3 ATA (the lowest pressure at which pressure can be felt, thereby ensuring the maintenance of masking). The main outcome measure was gross motor function. Secondary outcomes included performance in activities of daily living, attention, working memory, and speech. FINDINGS: For all outcomes, both groups improved over the course of the study, but without any difference between the two treatments. The score on the global gross motor function measure increased by 3.0% in the children on slightly pressurised air and 2.9% in those on hyperbaric oxygen. The mean difference between treatments was -0.40 (95% CI -1.69 to 0.90, p=0.544). Other changes were seen in speech, attention, memory, and functional skills. Ear problems occurred in 27 children treated by hyperbaric oxygen and in 15 treated with hyperbaric air (p=0.004). INTERPRETATION: In this study, hyperbaric oxygen did not improve the condition of children with cerebral palsy compared with slightly pressurised air. The improvement seen in both groups for all dimensions tested deserves further consideration. 

Review by David Weismantel, MD, Michigan State University family practice physician, CPON Co-Investigator.

What is the purpose of this study?

This study was undertaken to determine whether children with cerebral palsy benefit from hyperbaric oxygen treatment.

How was the study done?

The study enrolled 111 children with cerebral palsy between the ages of 3 and 12, recruited from 17 rehabilitation centers in Quebec. The children were randomized, in a double-blind, controlled trial, to either receive hyperbaric oxygen (1 hour in 100% oxygen at 1.75 atmospheres) or to receive slightly pressurized air (1 hour at 1.3 atmospheres). None of the investigators, children, or parents were aware of which child got which treatment. Over an 8-week study period, each child received 40 treatments.

For all of the measured outcomes, all children improved slightly, whether or not they were treated with hyperbaric oxygen.> There was no detectable difference in  improvement between the two groups. The score for global gross motor function increased by 2.9% with hyperbaric oxygen and by 3.0% with slightly pressurized air. Ear problems occurred in 27 children treated with hyperbaric oxygen but only in 15 treated with hyperbaric air (p+0.004).

This study was a randomized, double-blind study, which is considered the most rigorous study design for evaluating a treatment. It enrolled a substantial number of children. It was not possible for the parents, the treating doctors or the children themselves to know which treatment was received by which child. The children had a level of severity of CP that should have enabled the investigators to see improvement if it had been produced by the treatment.

What are the weaknesses of this study?

The children in this study were already receiving physical therapy services at the time of enrollment and may not represent those children who are not currently receiving such attention. Alternate or extended treatment schedules were not evaluated.

These results strongly suggest that hyperbaric oxygen is an ineffective way to improve motor function in most children with CP.