急性中耳炎に対する局所鎮痛
Abstract
Background
Acute otitis media (AOM) is a spontaneously remitting disease of which pain is the most distressing symptom. Antibiotics are now known to have less benefit than previously assumed. Topical pain relief may be a satisfactory intervention for AOM sufferers and encourage clinicians to prescribe fewer antibiotics.
Objectives
To assess the effectiveness of topical analgesia for AOM in adults and children.
Search methods
For this second update we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), Ovid MEDLINE (2008 to February Week 1 2011), Ovid MEDLINE (In‐Process & Other Non‐Indexed Citations 10 February 2011), Ovid EMBASE (2008 to 2011 Week 05), EBSCO CINAHL (2008 to 4 February 2011) and Ovid AMED (2008 to April 2011).
Selection criteria
Double‐blind randomised controlled trials (RCTs) or quasi‐RCTs comparing an otic preparation with an analgesic effect (excluding antibiotics) versus placebo or an otic preparation with an analgesic effect (excluding antibiotics) versus any other otic preparation with an analgesic effect, in adults or children presenting at primary care settings with AOM without perforation.
Data collection and analysis
Three review authors independently screened studies, assessed trial quality and extracted data. Attempts to obtain additional information from the trial authors of the included trials were unsuccessful.
Main results
Five trials including 391 children aged three to 18 years met our criteria. Two studies (117 children) compared anaesthetic ear drops versus placebo immediately at diagnosis. All children received some form of oral pain relief. In all five studies it was clear that ear pain diminishes rapidly for most sufferers. Nevertheless there was a statistically significant difference in the proportion of children achieving a 50% reduction in pain in favour of anaesthetic drops 10 minutes after instillation (risk ratio (RR) 2.13, 95% confidence interval (CI) 1.19 to 3.80) and 30 minutes after instillation (RR 1.43, 95% CI 1.12 to 1.81) on the day AOM was diagnosed but not at 20 minutes (RR 1.24, 95% CI 0.88 to 1.74). Three trials (274 children) compared anaesthetic ear drops with naturopathic herbal ear drops. Naturopathic drops were favoured 15 and 30 minutes after instillation, one to three days after diagnosis, but the differences were not statistically significant. Only one trial looked at adverse reactions and found none. Overall the findings of this review are based on trial evidence that is at low or unclear risk of bias.
Authors' conclusions
Evidence from five RCTs, only two of which addressed the most relevant question of primary effectiveness, provides limited evidence that ear drops are effective 30 minutes after administration in older children with AOM. Uncertainty exists as to the magnitude of this effect and more high‐quality studies are needed.
PICO
Plain language summary
急性中耳炎に対する局所鎮痛
抗菌薬は、単純性耳感染や耳痛の小児患者にとってほとんど違いはない。アメトプテリンやベンゾカイン、リドカインといった局所麻酔用点耳薬を推奨する者もいる。5件の試験（参加者391名）を確認した。その内2件は麻酔用点耳薬とプラセボ（不活性）点耳薬、3件は麻酔用点耳薬と薬草点耳薬を比較していた。薬草点耳薬が有効という強いエビデンスはないが、麻酔用点耳薬は不活性点耳薬よりも疼痛軽減の効果があった。1件の試験のみが副作用を検討したが、耳鳴りや歩行不安定の例は全くなく、非常に軽度の眩暈が3例報告されている。
全ての試験の小児で、点耳薬後に迅速かつ短期間の疼痛の軽減があった。これが疾患の自然経過の結果なのか、それとも治療を受けるというプラセボ効果、耳の中に何か液体があるという緩和作用、または点耳薬自体の薬理効果であるのか判断は難しい。しかし、経口鎮痛薬と併用した場合、3～18歳の小児の疼痛を麻酔用点耳薬はより早く軽減させるかもしれないというエビデンスもある。さらなる質の高い試験が必要である。
