Rusyniak

The use of hyperbaric oxygen therapy does not decrease disability following ischaemic stroke.

Clinical Bottom Line: 1. Hyperbaric oxygen therapy does not decrease disability after acute ischemic stroke 2. There is a trend for worse outcome following hyperbaric oxygen therapy.

Citation/s: Rusyniak DE, Kirk MA, May JD et al. Hyperbaric oxygen therapy in acute ischemic stroke. Results of the hyperbaric oxygen in acute ischaemic stroke trial pilot study. Stroke 2003;34:571-574. Lead author's name and fax: Daniel E. Rusyniak, MD

Three-part Clinical Question: In patients with acute ischaemic stroke, does the application of hyperbaric oxygen compared to standard measures result in any reduction in disability or death? Search Terms: Cerebrovascular accident, brain infarction

The Study: Double-blinded concealed randomised controlled trial with intention-to-treat. The Study Patients: Adults greater than 18 years of age with clinical characteristics of acute ischaemic stroke less than 24 hrs in duration. No haemorrhage on C/T. Control group (N = 16; 13 analysed): Single 'sham' treatment with 100% oxygen for 60 minutes at 1.14 ATA in a monoplace hyperbaric chamber Experimental group (N = 17; 17 analysed): Single treatment with 100% oxygen for 60 minutes at 2.5 ATA in a monoplace hyperbaric chamber

The Evidence:

Outcome	Time to Outcome	Sham rate	HBO rate	Relative risk reduction	Absolute risk reduction	NNT
Favourable NIHSS score	24 hrs	0.313	0.176	44%	0.14	7
95% CI				-49% to 100%	-0.15 to 0.43	NNT2 to INF NNH7 to INF
Favourable NIHSS score	90 days	0.500	0.294	41%	0.21	5
95% CI				-24% to 100%	-0.12 to 0.53	NNT2 to INF NNH=8 to INF
Death	90 days	0.188	0.118	37%	0.07	14
95% CI				-93% to 100%	-0.18 to 0.32	NNT3 to INF NNH=6 to INF

Comments: 1. NIHSS is a widely used disability scale specifically designed for stroke assessment. Favourable outcome was improvement >4 points or score of 0 at 24hrs, and score <=1 at 90 days. 2. Missing and dead patients allocated to unfavourable outcome in the 90 day analysis above. Analysis excluding these subjects difficult to interpret. 3. Single 60 min hyperbaric oxygen treatment is an unusual intervention. 4. Co-morbidities not described as potential confounders. 5. The control group was younger and predominantly white. Effect on result unknown. 6. Authors used results to abandon further investigation. 7. Three additional stroke scales used for 90 day analysis with no major differences.

Appraised by: Benjamin Kliot MD and Mike Bennett, Prince of Wales Hospital, Sydney;

• • Monday, 10 March 2003. Email: [| bkliot@mac.com].

Kill or Update By: July 2022