Transcutaneous electrical nerve stimulation (TENS) for pain management in labour

 

Abstract

Background

Transcutaneous nerve stimulation (TENS) has been proposed as a means of reducing pain in labour. The TENS unit emits low-voltage electrical impulses which vary in frequency and intensity. During labour, TENS electrodes are generally placed on the lower back, although TENS may be used to stimulate acupuncture points or other parts of the body. The physiological mechanisms whereby TENS relieves pain are uncertain. TENS machines are frequently operated by women, which may increase a sense of control in labour.

Objectives

To assess the effects of TENS on pain in labour.

Search methods

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2011) and reference lists of retrieved papers.

Selection criteria

Randomised controlled trials comparing women receiving TENS for pain management in labour versus routine care, alternative non-pharmacological methods of pain relief, or placebo devices. We included all types of TENS machines.

Data collection and analysis

Two review authors assessed for inclusion all trials identified by the search strategy, carried out data extraction and assessed risk of bias. We have recorded reasons for excluding studies.

Main results

Seventeen trials with 1466 women contribute data to the review. Thirteen examined TENS applied to the back, two to acupuncture points, and two to the cranium. Overall, there was little difference in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (average risk ratio 0.41, 95% confidence interval 0.31 to 0.54; measured in two studies). The majority of women using TENS said they would be willing to use it again in a future labour. Where TENS was used as an adjunct to epidural analgesia there was no evidence that it reduced pain. There was no consistent evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and babies. No adverse events were reported.

Authors' conclusions

There is only limited evidence that TENS reduces pain in labour and it does not seem to have any impact (either positive or negative) on other outcomes for mothers or babies. The use of TENS at home in early labour has not been evaluated. TENS is widely available in hospital settings and women should have the choice of using it in labour.

 

Plain language summary

TENS (transcutaneous nerve stimulation) for pain relief in labour

TENS is a device that emits low-voltage currents and which has been used for pain relief in labour. The way that TENS works is not well understood. The electrical pulses are thought to stimulate nerve pathways in the spinal cord which block the transmission of pain. In labour the electrodes from the TENS machine are usually attached to the lower back (and women themselves control the electrical currents using a hand-held device) but TENS can also be applied to acupuncture points or directly to the head. The purpose of the review was to see whether TENS is effective in relieving pain in labour. The review includes results from 17 studies with a total of 1466 women. Thirteen studies examined TENS applied to the back, two to acupuncture points and two to the cranium (head). Results show that pain scores were similar in women using TENS and in control groups. There was some evidence that women using TENS were less likely to rate their pain as severe but results were not consistent. Many women said they would be willing to use TENS again in a future labour. TENS did not seem have an effect on the length of labour, interventions in labour, or the well-being of mothers and babies. It is not known whether TENS would help women to manage pain at home in early labour. Although it is not clear that it reduces pain, women should have the choice of using TENS in labour if they think it will be helpful.

 

摘要

背景

懷孕時自發性血小板缺乏紫斑症之藥物治療

自發性血小板缺乏紫斑症是一種免疫反應引起的血小板過低症引起的血液異常。懷孕時自發性血小板缺乏紫斑症對母嬰風險的重要性有所爭議，自發性血小板缺乏紫斑症孕婦的生產處置也有爭議。懷孕時自發性血小板缺乏紫斑症之處置相當複雜，因為母親和胎兒之血小板數量不同。

目標

評估皮質類固醇、靜脈注射免疫球蛋白、長春花生物鹼類(Vinca alkaloids)、danazol、dapsone、和其他藥物用於治療懷孕時自發性血小板缺乏紫斑症之效果與安全性。

搜尋策略

我們搜尋Cochrane Pregnancy和Childbirth Group's Trials Register (2009年2月)、LILACS (1982年2009年2月8日)、ClinicalTrials.gov (2009年2月8日)、Current Controlled Trials (2009年2月16日)、Google Scholar (2009年2月16日)，以及相關文獻之參考資料中引述之進行中的與未發表的試驗。

選擇標準

任何用於治療懷孕時自發性血小板缺乏紫斑症之隨機控制試驗(Randomised controlled trials (RCTs))。

資料收集與分析

2位回顧作者獨立評估方法學品質以及摘錄資料，若有意見不一致時，則討論或與第3位回顧作者諮商。

主要結論

本回顧納入1篇隨機控制研究，有38名婦女(41次懷孕經驗)被隨機分組，只有26名婦女(28次懷孕經驗)被分析。這篇隨機控制研究比較使用betamethasone (1.5 mg/day)和未用藥的效果，發現新生兒血小板過低症(RR為1.12, 95% CI為0.62 – 2.05)以及新生兒出血(RR為1.00, 95% CI為0.24 – 4.13)並無統計上的顯著差異。回顧作者進行治療意向分析(intentiontotreat analysis)，得到相似的結果：分別是RR為1.18, 95% CI為0.57 – 2.45、RR為1.05, 95% CI為0.24 – 4.61。這篇隨機控制研究並未探討母親之死亡、出生前後死亡、產後出血以及新生兒顱內出血。

作者結論

目前的證據指出，與未使用藥物比較，betamethasone不會減少懷孕時自發性血小板缺乏紫斑症孕婦之新生兒血小板過低症和新生兒出血風險，沒有足夠證據支持使用betamethasone治療懷孕時自發性血小板缺乏紫斑症。此次的Cochrane review並未提供其它用於懷孕時自發性血小板缺乏紫斑症的藥物治療證據。此次系統性回顧發現需要設計良好、適當強度的隨機臨床試驗，探討自發性血小板缺乏紫斑症孕婦的醫療處置。如果用Betamesasone作為自發性血小板缺乏紫斑症孕婦的治療方式，需要有經隨機臨床試驗證實的治療有效證據，也需權衡利弊。任何將來有關此疾病孕婦藥物治療的臨床試驗，應探討母親死亡、週產期死亡、產後出血和新生兒顱內出血等有關母嬰健康的重要議題 。

翻譯人

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

懷孕時自發性血小板缺乏紫斑症之藥物治療：自發性血小板缺乏紫斑症是一種因免疫反應使血小板數量減少的(血小板過低症)血液異常。抗血小板抗體的血小板作用導致脾臟破壞血小板。就成人而言，自發性血小板缺乏紫斑症之臨床特徵通常是不知不覺發生，且變化相當大：沒有症狀、輕微挫傷、黏膜出血、皮膚變色。懷孕時自發性血小板缺乏紫斑症之處置很複雜，因為母親和胎兒的血小板數量不一樣。血液循環中的抗體會通過胎盤，引起新生兒被動免疫血小板過低，而增加新生兒腦出血風險，因此，對嬰兒來說，剖腹產似乎比自然產更安全，但是生產方式對出血率似乎沒有影響。有多種藥物被用來治療這個疾病，孕婦之自發性血小板缺乏紫斑症治療並無標準，有部份藥物可能對孕婦有副作用，有些則會引起胎兒畸形。現有的一篇隨機控制試驗的證據指出，對於懷孕時自發性血小板缺乏紫斑症，相較於未治療，betamethasone不會減少新生兒血小板過低和新生兒出血的風險。我們並未找到其他懷孕時自發性血小板缺乏紫斑症藥物治療方式的研究證據。此次回顧納入1篇試驗、有38名婦女(41次懷孕經驗)被隨機分組，只有26名婦女的資料(28次懷孕經驗)用於分析。比較之組別之間有相當大的差異。給予母親betamethasone (1.5 mg/day)，對於新生兒出生後一週內的血小板數量並不會有影響。研究報告指出，在研究期間，betamethasone組和無治療組，母親週邊血液的血小板數量並未顯著改變。並未探討母親產後出血與新生兒顱內出血，也沒有關於母親之臨床和懷孕結果的報告。研究者在對照組並未使用治療方式，這可能會增加試驗的執行偏差。