From the Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
Respiratory Motion, Inc, Watertown, Massachusetts.
Anesth Analg. 2022 Jan 1;134(1):141-148. doi: 10.1213/ANE.0000000000005562.
The respiratory volume monitor (RVM) (ExSpiron, Respiratory Motion Inc, Watertown, MA) uses thoracic impedance technology to noninvasively and continuously measure tidal volume (TV), respiratory rate (RR), and minute ventilation (MV). We aimed to validate the accuracy of the RVM to assess ventilation in neonates and infants by comparing it to spirometry.
We used the RVM and Respironics NM3 spirometer (Respironics NM3 Respiratory Profile Monitor, Philips Healthcare, Amsterdam, the Netherlands) to record simultaneous and continuous measurements of MV, TV, and RR. The RVM measurements, with and without external calibration, were compared to the Respironics NM3 spirometer using Bland-Altman analysis. The relative errors (Bland-Altman) between RVM and Respironics NM3 were calculated and used to compute individual patient bias, precision, and accuracy as the mean error, the standard deviation (SD) of the error, and the root mean square error. Bland-Altman limits of agreement (LoA) were computed, and equivalence tests were performed.
Forty patients were studied to compare the RVM and Respironics NM3 measurements. The mean difference (ie, bias) for MV was 1.8% with 95% LoA, defined as mean ± 1.96 SD, in the range of -12.1% to 15.7%. Similarly, the mean difference (ie, bias) for TV and RR was 1.2% (95% LoA, -11.0% to 13.5%) and 0.6% (95% LoA, -3.7% to 5.0%), respectively. The mean measurement precision of the RVM relative to the Respironics NM3 for MV, TV, and RR was 10.8%, 8.9%, and 8.4%, respectively. The mean measurement accuracy for MV, TV, and RR across patients was 11.0%, 9.7%, and 7.1%, respectively.
The data demonstrate that the RVM measures TV and MV in this cohort with an average relative error of 11% when using patient calibration and 16.9% without patient calibration. The average relative error of RR was 7.1%. The RVM provides accurate measurement of RR, TV, and MV in mechanically ventilated neonates and infants.
呼吸容量监测仪（RVM）（ExSpiron，Respiratory Motion Inc，马萨诸塞州沃特敦）使用胸部阻抗技术无创且连续地测量潮气量（TV）、呼吸频率（RR）和分钟通气量（MV）。我们旨在通过与肺活量计比较来验证 RVM 评估新生儿和婴儿通气的准确性。
我们使用 RVM 和Respironics NM3 肺活量计（Respironics NM3 呼吸分析监测仪，荷兰皇家飞利浦公司）同时记录 MV、TV 和 RR 的连续测量值。使用 Bland-Altman 分析比较 RVM 测量值（带和不带外部校准）与 Respironics NM3 肺活量计。计算 RVM 和 Respironics NM3 之间的相对误差（Bland-Altman），并使用平均误差、误差的标准差（SD）和均方根误差来计算个体患者的偏差、精度和准确性。计算 Bland-Altman 协议范围（LoA）并进行等效性检验。
研究了 40 例患者以比较 RVM 和 Respironics NM3 测量值。MV 的平均差值（即偏差）为 1.8%，95% LoA 定义为均值±1.96 SD，范围为-12.1%至 15.7%。类似地，TV 和 RR 的平均差值（即偏差）分别为 1.2%（95% LoA，-11.0%至 13.5%）和 0.6%（95% LoA，-3.7%至 5.0%）。RVM 相对于 Respironics NM3 的 MV、TV 和 RR 的平均测量精度分别为 10.8%、8.9%和 8.4%。MV、TV 和 RR 在患者中的平均测量精度分别为 11.0%、9.7%和 7.1%。
数据表明，当使用患者校准时，RVM 在该队列中测量 TV 和 MV 的平均相对误差为 11%，而不使用患者校准时为 16.9%。RR 的平均相对误差为 7.1%。RVM 可在机械通气的新生儿和婴儿中准确测量 RR、TV 和 MV。
