Hyperventilation therapy for acute traumatic brain injury
Editorial Group: Cochrane Injuries Group
Published Online: 20 OCT 1997
Assessed as up-to-date: 6 JAN 2008
Copyright © 2009 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Roberts I, Schierhout G. Hyperventilation therapy for acute traumatic brain injury. Cochrane Database of Systematic Reviews 1997, Issue 4. Art. No.: CD000566. DOI: 10.1002/14651858.CD000566.
- Publication Status: New search for studies and content updated (no change to conclusions)
- Published Online: 20 OCT 1997
Because hyperventilation is often associated with a rapid fall in intracranial pressure, it has been assumed to be effective in the treatment of severe head injury. Hyperventilation reduces raised intracranial pressure by causing cerebral vasoconstriction and a reduction in cerebral blood flow. Whether or not reduced cerebral blood flow improves neurological outcome is, however, unclear.
To quantify the effect of hyperventilation on death and neurological disability following head injury.
We searched the following electronic databases: the Cochrane Injuries Group Specialised Register, CENTRAL (The Cochrane Library 2007, Issue 4), MEDLINE, PubMed, EMBASE, PsycINFO. We searched the Internet, checked reference lists of relevant studies, and contacted the first author of eligible reports to ask for assistance in identifying any further trials. The searches were updated in January 2008.
All randomised trials of hyperventilation, in which study participants had a clinically defined acute traumatic head injury of any severity. There were no language restrictions.
Data collection and analysis
We collected data on the participants, the timing and duration of the intervention, duration of follow-up, neurological disability and death. Relative risks (RR) and 95% confidence intervals (CI) were calculated for each trial on an intention-to-treat basis. Timing, degree and duration of hyperventilation were identified a-priori as potential sources of heterogeneity between trials.
One trial of 113 participants was identified. Hyperventilation alone, as well as in conjunction with a buffer (THAM [tris-hydroxy-methyl-amino methane]), showed a beneficial effect on mortality at one year after injury, although the effect measure was imprecise (RR 0.73; 95% CI 0.36 to 1.49, and RR 0.89; 95% CI 0.47 to 1.72 respectively). This improvement in outcome was not supported by an improvement in neurological recovery. For hyperventilation alone, the RR for death or severe disability was 1.14 (95% CI 0.82 to 1.58). The RR for death or severe disability in the hyperventilation-plus-THAM group was 0.87 (95% CI 0.58 to 1.28).
The data available are inadequate to assess any potential benefit or harm that might result from hyperventilation in severe head injury. Randomised controlled trials to assess the effectiveness of hyperventilation therapy following severe head injury are needed.
Plain language summary
Not enough evidence on whether hyperventilation therapy improves outcomes for people with traumatic brain injury
Traumatic brain injury is a major cause of premature death and disability. Severe head injury can trigger brain swelling, thereby increasing pressure on the brain (raised intracranial pressure, ICP). Raised ICP increases the likelihood of brain damage or death. Treatment to lower people's ICP commonly involves hyperventilation therapy (increasing blood oxygen levels) following the brain injury. While hyperventilation therapy can reduce ICP after traumatic brain injury, the review of trials found there is no strong evidence about whether this improves outcomes. More trials are needed.
我們使用預先設定的搜尋策略，搜尋Cochrane Injuries Group's specialised register、the Cochrane Central Register of Controlled Trials、MEDLINE、PubMed、EMBASE和NRR等之電子資料庫。 我們另經由網路搜尋，找出參考資料之相關研究，並與研究發表之第一作者聯繫，尋求協助確認是否有其他之研究。資料搜尋更新至2006年3月。
1個試驗包括113個參加者。 換氣過度單獨，以及併用緩衝劑(THAM [tris羥甲醇氨基甲烷一道])，雖然結果測量的項目不正確，但受傷一年以後死亡率顯示有利的結果，(分別為RR 0.73; 95% CI 0.36到1.49和RR 0.89; 95% CI 0.47到1.72)。intentiontotreat的結果不能由神經學補救的改善而獲得支持。換氣過度， 死亡或嚴厲傷殘RR是1.14 (95% CI 0.82到1.58)。 在換氣過度加上THAM小組，死亡或嚴厲傷殘RR是0.87 (95% CI 0.58到1.28)。
此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。
沒有足夠的證據確認換氣過度療法是否改進腦損傷。腦損傷是夭折和傷殘的主因。 嚴重頭部受傷(上升的顱內的壓力， ICP)可能觸發腦膨脹，因此壓力增長。上升的ICP增加腦損傷或死亡可能性。 腦損傷時通常用換氣過度療法以降低ICP及增加血液氧氣成水平。 當換氣過度療法可能在創傷腦傷以後減少ICP，找到的試驗回顧裡是沒有強力的證據支持這項結論。 更多試驗是需要的。