Hyperbaric
oxygen did not improve outcome in head injury patients with coma.
Clinical
Bottom Line:
1.
No evidence for improvement in mortality or wakefulness in head injured
patients treated with hyperbaric oxygen
2.
Some weak evidence of effect in young, initially unresponsive patients with
brain stem contusion on sub-group analysis.
Appraised
by:
Mike Bennett, Dept of Diving and Hyperbaric Medicine
Prince
of Wales Hospital, Sydney; Thursday,
21 January, 1999
Clinical
Scenario:
A 30 year old male with a traumatic head injury resulting in coma and with
global cerebral oedema.
Three-part
Question:
In comatose patients following head injury, does the administration of
hyperbaric oxygen in addition to all usual care, result in any improvement in
recovery from brain injury?
Search
Terms:
Hyperbaric oxygenation, head injury, brain injuries.
The
Study:
Non-blinded
randomised controlled trial with intention-to-treat.
Patients
with history of head injury leading to coma and admitted to a neurological
intensive care unit.
Control
group (N = 29; 29 analysed): Usual management including intubation, mechanical
ventilation and frusemide administration in the majority. Operative neurosurgery
where indicated.
Experimental
group (N = 31; 31 analysed): As above plus oxygen at 2.5 ATA for 60 minutes (90
minute cycle) for 10 days with 4 days break and repetition of the cycle until
return of consciousness or death. Average 10.5 sessions.
The
Evidence:
|
Outcome |
Time
to Outcome |
Control
rate |
HBO
rate |
Relative
risk reduction |
Absolute
risk reduction |
NNT |
|
Death |
1
year |
0.55 |
0.48 |
12% |
0.068 |
15 |
|
95%
CI: |
|
|
|
-33%
to 58% |
-0.18
to 0.32 |
NNT
= 3 to INF NNH =
5 to INF |
Non-Event
Outcomes Control
group HBO group P-value
Duration
of coma
(days)
32.7
28.2
>0.05
Comments:
1.
60 patients out of 185 recruited due to chamber availability- selection bias may
reduce validity of this study.
2.
Subgroup analysis of patients <30 years with brain stem contusion and
initially unresponsive to painful stimuli suggest there may be a benefit in this
group.
3.
Due to complications and logistic difficulties, only 17 of 31 HBO patients
received 4 or more HBO sessions, reducing any treatment effect.
4.
Somewhat inconclusive study.
Expiry
date:
September
2005
References:
1.
Artru F, Chacornac R, Deleuze R. Hyperbaric oxygenation for severe head
injuries. Preliminary results of a controlled study. European Neurology 1976;
14:310-318.
