改良型磁共振兼容温度探头在儿童中的性能验证。

Department of Anesthesiology, Tufts Medical Center, Boston, MA 02111, USA.

Anesth Analg. 2012 Jun;114(6):1230-4. doi: 10.1213/ANE.0b013e31824b003e. Epub 2012 Feb 24.

INTRODUCTION

During magnetic resonance imaging (MRI), children are at risk for body temperature variations. The cold MRI environment that preserves the MRI magnet can cause serious hypothermia. On the other hand, hyperthermia may also develop because of radiofrequency-induced heating of the tissues, particularly in prolonged examinations. Because of a lack of MRI-compatible core temperature probes, temperature assessment is unreliable, and specific absorption rate-related patient heat gain must be calculated to determine the allowable scan duration. We compared an MRI-compatible temperature probe and a modification thereof to a standard esophageal core body temperature probe in children.

METHODS

Children undergoing general anesthesia were recruited, each patient serving as his/her own control. Core body temperature was measured using 3 different devices: (1) a fiberoptic MRI-compatible skin surface temperature probe (MRI-skin) located on the child's skin surface; (2) a fiberoptic MRI-compatible temperature probe modified with a single-use sleeve at the tip (MRI-core), located in the nasopharynx; and (3) a standard temperature monitor (STRD) located in the esophagus or nasopharynx. The Bland-Altman method was used for statistical analysis.

RESULTS

We enrolled 60 children aged 7.8 ± 6 years (mean ± SD) weighing 32.4 (±26.4) kg. The estimated difference between the STRD and MRI-core measurements of core temperature was 0.06°C (confidence interval [CI]: -0.02, 0.15), and between the STRD and the MRI-skin 1.19°C (CI: 0.97, 1.41). According to the Bland-Altman analysis, the 95% limits of agreement ranged from -0.9 to 3.4 and from -1.3 to 1.2 between the STRD and the MRI-skin probe and the MRI-core probe, respectively.

DISCUSSION

Our results show good agreement between standard esophageal measurements of core temperature and core temperature measured using a modified MRI-core probe during general anesthesia in a general surgical pediatric population. The ability to accurately assess core temperature in the MRI suite may safely allow longer scan times and therefore reduce repeat anesthetic exposure, improve patient safety, and enhance the quality of care in children.

简介

在磁共振成像（MRI）期间，儿童存在体温变化的风险。为了保护 MRI 磁体，冷 MRI 环境可能导致严重的体温过低。另一方面，由于组织的射频诱导加热，也可能发生体温过高，尤其是在长时间检查中。由于缺乏 MRI 兼容的核心温度探头，因此温度评估不可靠，必须计算与特定吸收率相关的患者热量增加，以确定允许的扫描持续时间。我们比较了 MRI 兼容的温度探头及其改良探头与儿童标准食管核心体温探头的性能。

方法

我们招募了接受全身麻醉的儿童，每位患者都作为自身对照。使用 3 种不同的设备测量核心体温：（1）位于儿童皮肤表面的光纤 MRI 兼容皮肤表面温度探头（MRI-skin）；（2）在尖端带有一次性套管的光纤 MRI 兼容温度探头（MRI-core），位于鼻咽部；（3）位于食管或鼻咽部的标准温度监测器（STRD）。使用 Bland-Altman 方法进行统计分析。

结果

我们纳入了 60 名年龄为 7.8 ± 6 岁（均值 ± 标准差）、体重为 32.4（±26.4）kg 的儿童。STRD 与 MRI-core 测量的核心体温之间的估计差值为 0.06°C（置信区间：-0.02，0.15），STRD 与 MRI-skin 之间的差值为 1.19°C（置信区间：0.97，1.41）。根据 Bland-Altman 分析，STRD 与 MRI-skin 探头和 MRI-core 探头之间的 95%一致性界限分别为-0.9 至 3.4 和-1.3 至 1.2。