Chandrasekaran Ashok, Amboiram Prakash, Balakrishnan Umamaheswari, Abiramalatha Thangaraj, Rao Govind, Jan Shaik Mohammad Shafi, Rajendran Usha Devi, Sekar Uma, Thiruvengadam Gayathri, Ninan Binu
Department of Neonatology, Sri Ramachandra Medical College and Research Institute, Porur, Chennai, India.
Center for Advanced Sensor Technology, Technology Research Center, University of Maryland, Baltimore County, Baltimore, United States.
EClinicalMedicine. 2020 Dec 7;31:100664. doi: 10.1016/j.eclinm.2020.100664. eCollection 2021 Jan.
Incubators and radiant warmers are essential equipment in neonatal care, but the typical 1,500 to 35,000 USD cost per device makes it unaffordable for many units in low and middle-income countries. We aimed to determine whether stable preterm infants could maintain thermoregulation for 48 h in a low-cost incubator (LCI).
The LCI was constructed using a servo-heater costing 200 USD and cardboard infant-chamber. We conducted this open-labeled non-inferiority randomized controlled trial in a tertiary level teaching hospital in India from May 2017 to March 2018. Preterm infants on full feeds and receiving incubator or radiant warmer care were enrolled at 32 to 36 weeks post-menstrual age. We enrolled 96 infants in two strata (Strata-1< 33 weeks, Strata-2 ≥ 33 weeks at birth). Infants were randomized to LCI or standard single-wall incubator (SSI) after negative incubator cultures and monitored for 48 h in air-mode along with kangaroo mother care. The incubator temperature was adjusted manually to maintain skin and axillary temperatures between 36.5 °C and 37.5 °C. During post-infant period after 48 h, SSI and LCI worked for 5 days and incubator temperatures were measured. The primary outcome was maintenance of skin and axillary temperatures with a non-inferiority margin of 0.2 °C. Failed thermoregulation was defined as abnormal axillary temperature (< 36.5 °C or >37.5 °C) for > 30 continuous-minutes. Secondary outcomes were incidence of hypothermia and required incubator temperature. Trial registration details: Clinical Trial Registry - India (CTRI/2015/10/006316).
Prior to enrollment 79(82%) infants were in radiant warmer and 17(18%) infants were in incubator care. Median weight at enrollment in Strata-1 and Strata-2 for SSI vs. LCI was 1355(IQR 1250-1468) vs. 1415(IQR 1280-1582) and 1993(IQR 1595-2160) vs. 1995(IQR 1632-2237) grams. Mean skin temperature in Strata-1 and Strata-2 for SSI vs. LCI was 36.8 ° ± 0.2 vs. 36.7 ° ± 0.18 and 36.8 ° ± 0.22 vs. 36.7 ° ± 0.19. Mean axillary temperature in Strata-1 and Strata-2 for SSI vs. LCI was 36.9 ° ± 0.19 vs. 36.8 ° ± 0.16 and 36.8 ° ± 0.2 vs. 36.8 ° ± 0.19. Mixed-effect model done for repeated measures of skin and axillary temperatures showed the estimates were within the non-inferiority limit; -0.07 °C (95% CI -0.11 to -0.04) and -0.06 °C (95% CI -0.095 to -0.02), respectively. Failed thermoregulation did not occur in any infants. Mild hypothermia occurred in 11 of 48(23%) of SSI and 16 of 48(33%) of LCI, OR 1.28 (95%CI 0.85 to 1.91). Incubator temperature in LCI was higher by 0.7 °C (95%CI 0.52 to 0.91). In the post-infant period SSI and LCI had excellent reliability to maintain set-temperature with intra-class correlation coefficient of 0.93 (95%CI 0.92 to 0.94) and 0.96 (95%CI 0.96 to 0.97), respectively.
Maintenance of skin and axillary temperature of stable preterm infants in LCI along with kangaroo mother care was non-inferior to SSI, but at a higher incubator temperature by 0.7 °C. No adverse events occurred and LCI had excellent reliability to maintained set-temperature.
Food and Drug Administration (Award number P50FD004895).
婴儿培养箱和辐射保暖台是新生儿护理中的重要设备，但每台设备1500至35000美元的典型成本让许多低收入和中等收入国家的医疗机构难以承受。我们旨在确定稳定的早产儿在低成本培养箱（LCI）中能否维持48小时的体温调节。
LCI由一台售价200美元的伺服加热器和硬纸板婴儿舱构成。2017年5月至2018年3月，我们在印度一家三级教学医院开展了这项开放标签的非劣效性随机对照试验。纳入月经龄32至36周、完全经口喂养且接受培养箱或辐射保暖台护理的早产儿。我们将96名婴儿分为两层（第1层<33周，第2层出生时≥33周）。培养箱培养结果为阴性后，将婴儿随机分配至LCI组或标准单壁培养箱（SSI）组，并在空气模式下结合袋鼠式护理监测48小时。手动调节培养箱温度，使皮肤和腋窝温度维持在36.5°C至37.5°C之间。48小时后的婴儿期，SSI和LCI持续工作5天并测量培养箱温度。主要结局是维持皮肤和腋窝温度，非劣效界值为0.2°C。体温调节失败定义为腋窝温度异常（<36.5°C或>37.5°C）持续超过30分钟。次要结局是体温过低的发生率和所需的培养箱温度。试验注册详情：印度临床试验注册中心（CTRI/2015/10/006316）。
入组前，79名（82%）婴儿接受辐射保暖台护理，17名（18%）婴儿接受培养箱护理。SSI组与LCI组第1层和第2层入组时的体重中位数分别为1355（四分位间距1250 - 1468）对1415（四分位间距1280 - 1582）克和1993（四分位间距1595 - 2160）对1995（四分位间距1632 - 2237）克。SSI组与LCI组第1层和第2层的平均皮肤温度分别为36.8°±0.2对36.7°±0.18和36.8°±0.22对36.7°±0.19。SSI组与LCI组第1层和第2层的平均腋窝温度分别为36.9°±0.19对36.8°±0.16和36.8°±0.2对36.8°±0.19。对皮肤和腋窝温度的重复测量进行的混合效应模型显示，估计值在非劣效限度内；分别为-0.07°C（95%置信区间-0.11至-0.04）和-0.06°C（95%置信区间-0.095至-0.02）。没有婴儿出现体温调节失败。48名SSI组婴儿中有11名（23%）、48名LCI组婴儿中有16名（33%）发生轻度体温过低，比值比为1.28（95%置信区间0.85至1.91）。LCI组的培养箱温度高0.7°C（95%置信区间0.52至0.91）。在婴儿期后，SSI和LCI维持设定温度的可靠性极佳，组内相关系数分别为0.93（95%置信区间0.92至0.94）和0.96（95%置信区间0.96至0.97）。
在袋鼠式护理的同时，LCI维持稳定早产儿皮肤和腋窝温度的效果不劣于SSI，但培养箱温度高0.7°C。未发生不良事件，且LCI维持设定温度的可靠性极佳。
美国食品药品监督管理局（资助编号P50FD004895）
