Intervention Review

Double wall versus single wall incubator for reducing heat loss in very low birth weight infants in incubators

  1. Nirupama Laroia1,*,
  2. Dale Phelps2,
  3. Jason Roy3

Editorial Group: Cochrane Neonatal Group

Published Online: 18 APR 2007

Assessed as up-to-date: 21 DEC 2009

DOI: 10.1002/14651858.CD004215.pub2


How to Cite

Laroia N, Phelps D, Roy J. Double wall versus single wall incubator for reducing heat loss in very low birth weight infants in incubators. Cochrane Database of Systematic Reviews 2007, Issue 2. Art. No.: CD004215. DOI: 10.1002/14651858.CD004215.pub2.

Author Information

  1. 1

    University of Rochester, Department of Pediatrics, Rochester, New York, USA

  2. 2

    University of Rochester, Pediatrics, New York, 14642, USA

  3. 3

    University of Rochester, Biostatistics, Rochester, New York, USA

*Nirupama Laroia, Department of Pediatrics, University of Rochester, 601 Elmwood Avenue, Box 651, Rochester, New York, 14642, USA. Nirupama_Laroia@URMC.Rochester.edu.

Publication History

  1. Publication Status: New search for studies and content updated (no change to conclusions)
  2. Published Online: 18 APR 2007

SEARCH

 

Abstract

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要
  5. Plain language summary

Background

Studies have shown improved survival of newborn infants maintained in the thermoneutral range. Incubators with a double plexiglass wall for additional insulation may help to provide an improved thermoneutral environment for very low birth weight infants.

Objectives

To assess the effects of double walled incubator versus a single wall incubator on insensible water loss, rate of oxygen consumption, episodes of hypothermia, time to regain birth weight, duration of hospitalization and infant mortality in premature infants.

Search methods

The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of electronic databases: Oxford Database of Perinatal Trials, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2006), MEDLINE (1966 to 2006), EMBASE, previous reviews including cross references, abstracts, conference and symposia proceedings, expert informants in all published languages, and CINAHL (1982 to 2006). The electronic search was updated in July 2009.

Selection criteria

Only studies using random or quasi-random methods of allocation were considered for this review. Eligible studies assessed at least one of the outcome variables identified as important to this topic.

Data collection and analysis

Independent data extraction and quality assessment of included trials was conducted by the review authors. Data were analyzed using generic inverse variance methodology and weighted mean difference (WMD). Results are presented with 95% confidence intervals. Meta-analysis was undertaken using a fixed effect model.

Main results

Three studies met the criteria. Four other studies were excluded, as they did not compare double versus single wall incubators. Double wall incubators have the advantage of decreasing heat loss, decreasing heat production and decreasing radiant heat loss when compared to single wall incubators. There is also the advantage of reduced oxygen consumption. A minimal increase in conductive heat loss was noted when compared to single wall incubators. All of these effects are small and do not support the proposition that double wall incubators have a beneficial effect on long-term outcomes including mortality or the duration of hospitalization.

Authors' conclusions

Although it appears that caring for extremely small infants in double wall incubators may theoretically result in shorter hospitalization and may have metabolic advantages, this review was unable to find any data in the literature to support or refute this hypothesis. The studies do not provide any evidence that the small decrease in heat loss improves clinical outcome. Therefore, the available data is insufficient to directly guide clinical practice.

 

Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要
  5. Plain language summary

Double wall versus single wall incubator for reducing heat loss in very low birth weight infants in incubators

Newborn infants maintained in the appropriate temperature range have a better chance of surviving. When newborn infants are within the appropriate temperature range, they burn less energy and have improved growth. The concept of an incubator with additional insulation, namely a double wall of plexiglass, is appealing as it may help very low birth weight infants maintain this appropriate temperature environment. We assessed the effects of double wall incubators compared to single wall incubators on the energy needs and water balance of very low birth weight infants. In addition, we looked at important clinical outcomes such as growth, length of hospital stay and survival. Three studies were found that met our criteria. The double wall incubators had advantages as far as decreasing heat loss and decreasing heat production. These infants seemed to be in the best temperature range, as their need to burn energy was less. However, these effects were small and did not provide any evidence of any long-term improvement regarding duration of hospitalization or survival. Although it appears that caring for extremely small infants in double wall incubators may result in certain metabolic advantages, this review was unable to find any data in the literature to support or refute this theory. Available data is insufficient to directly guide clinical practice.

 

摘要

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要
  5. Plain language summary

背景

比較雙層與單層牆壁的保溫箱在減少極低出生體重嬰兒體溫上的喪失

研究顯示保持新生兒在中心體溫範圍內可改善其存活率。利用一雙層塑膠玻璃加強保溫箱絕緣的概念,似乎能幫助提供極低出生體重嬰兒保持在中心體溫範圍之環境中。

目標

評估雙層與單層牆壁的保溫箱,比較兩者在早產兒之無感水份流失量,耗氧率,低體溫發生次數,恢復誕生時體重的時間,住院天數和嬰兒死亡率的影響。

搜尋策略

利用考科藍新生兒回顧組的標準檢索策略搜尋。這包括電子數據庫的搜尋︰周產期試驗的牛津數據庫,考科藍中央登錄的對照試驗(CENTRAL,考科藍圖書館,第1期,2006年),線上醫學檔案分析和檢索系統(MEDLINE 1966 – 2006年),EMBASE,過去的回顧包含交叉索引,摘要,會議和專題討論會記錄,所有出版語言的專家資料和CINAHL(1982 – 2006年)。

選擇標準

這篇回顧只採用有使用隨機或者半隨機取樣方法的研究。其中至少有一變項被評為重要結果才能算是合格的研究。

資料收集與分析

實驗的獨立數據分析和品質的評估由回顧作者進行。數據分析使用一般倒轉變化方法學和weighted mean difference (WMD)。結果以95%的置信區間表現。使用固定效應模組來做變項分析。

主要結論

三項研究達到標準。其他四項研究被排除,因為他們沒有作雙層與單層牆壁的保溫箱的比較(研究的細節詳述在研究的接受及排除的單元)。雙層比單層牆壁的保溫箱有更多的優點,包括減少熱散失,減少熱產生並且減少輻射熱散失。還有減低耗氧的優點,但卻輕微的增加傳導熱散失。這些效果太小,以致不能證實雙層牆壁的保溫箱,對死亡率或住院天數等長期影響有正面的效果。

作者結論

理論上,利用雙層牆壁的保溫箱照顧極小嬰兒,彷彿可縮短住院天數和獲得代謝上的優點,但是,這篇回顧卻找不到文獻上的任何數據支持或者反駁這個假說。沒有研究能提供任何證據若減少熱散失能改善臨床的結果。因此,以現有的數據是不足以直接指引臨床上的使用。

翻譯人

本摘要由臺中榮民總醫院王瑩翻譯。

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

總結

新生兒若保持在適當溫度範圍內應可獲得更好的存活機會。當新生的嬰兒是在合適的溫度範圍內時,他們會燃燒較少的能量並可促進生長。利用一雙層塑膠玻璃加強保溫箱絕緣的概念,似乎能幫助提供極低出生體重嬰兒保持在適當溫度範圍之環境中。我們提出雙層與單層牆壁的保溫箱的比較,前者在極低出生體重早產兒之能量需求及水份平衡上有更好的影響。另外,我們也要求重要的臨床結果(例如生長發育,住院天數和存活率)。有三項研究達到我們的標準。雙層牆壁保溫箱的優點有減少熱散失及減少熱產生。這些嬰兒彷彿保持在最好的溫度範圍內而較少消耗能量。但是,這些效果太小,以致不能證實可改善住院天數或死亡率等長期影響。雖然,利用雙層牆壁的保溫箱照顧極小嬰兒,彷彿可獲得某些代謝上的優點,但是,這篇回顧卻找不到文獻上的任何數據支持或者反駁這個假說。以現有的數據是不足以直接指引臨床上的使用。

 

Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要
  5. Plain language summary

Inkubator s dvostrukim zidom naspram jednostrukim zidom za smanjenje gubitka topline u dojenčadi s vrlo niskom porođajnom težinom koja boravi u inkubatorima

Inkubator s dvostrukim zidom naspram jednostrukim zidom za smanjenje gubitka topline u dojenčadi s vrlo niskom porođajnom težinom koja boravi u inkubatorima

Novorođenčad koju se održava u odgovarajućem temperaturnom rasponu ima bolje šanse za preživljavanje. Kada je novorođenčad u odgovarajućem temperaturnom rasponu, ona troši manje energije i ima poboljšan rast. Koncept inkubatora s dodatnom izolacijom, odnosno dvostrukim zidom od pleksiglasa, privlačan je jer može pomoći dojenčadi s vrlo malom porođajnom težinom zadržati ovu odgovarajuću temperaturu okoline. Procijenili smo učinke inkubatora s dvostrukim zidom u usporedbi s inkubatorima s jednostrukim zidom na energetske potrebe i ravnotežu vode u dojenčadi s vrlo niskom porođajnom težinom. Osim toga, promatrali smo važne kliničke ishode, kao što su rast, duljina boravka u bolnici i preživljavanje. Nađene su tri studije koje su udovoljavale našim kriterijima. Inkubatori s dvostrukim zidom imali su prednosti što se tiče smanjenja gubitka topline i smanjenja stvaranja topline. Činilo se da je ta dojenčad u najboljem temperaturnom rasponu, jer je njihova potreba za sagorijevanjem energije bila manja. Međutim, ti su učinci bili mali i nisu dali dokaze o bilo kakvom dugoročnom poboljšanju glede trajanja hospitalizacije ili preživljavanja. Iako se čini kako skrb za iznimno malu dojenčad u inkubatorima s dvostrukim zidom može imati određene metaboličke prednosti, ovaj pregled u literaturi nije mogao pronaći bilo kakve podatke za potporu ili opovrgavanje ove teorije. Dostupni podaci nisu dovoljni kako bi izravno dali smjernice za kliničku praksu.

Translation notes

Translated by: Croatian Branch of the Italian Cochrane Centre