INCA Group, Royal College of Surgeons in Ireland Clinical Research Centre, Dublin, Ireland.
Beaumont Hospital, Royal College of Surgeons in Ireland, Dublin, Ireland.
Physiol Meas. 2021 Jun 29;42(6). doi: 10.1088/1361-6579/ac05d5.
Respiratory rate (RR) is routinely used to monitor patients with infectious, cardiac and respiratory diseases and is a component of early warning scores used to predict patient deterioration. However, it is often measured visually with considerable bias and inaccuracy.. Firstly, to compare distribution and accuracy of electronically measured RR (EMRR) and visually measured RR (VMRR). Secondly, to determine whether, and how far in advance, continuous electronic RR monitoring can predict oncoming hypoxic and pyrexic episodes in infectious respiratory disease.A retrospective cohort study analysing the difference between EMRR and VMRR was conducted using patient data from a large tertiary hospital. Cox proportional hazards models were used to determine whether continuous, EMRR measurements could predict oncoming hypoxic (SpO < 92%) and pyrexic (temperature >38 °C) episodes.Data were gathered from 34 COVID-19 patients, from which a total of 3445 observations of VMRR (independent of Hawthorne effect), peripheral oxygen saturation and temperature and 729 117 observations of EMRR were collected. VMRR had peaks in distribution at 18 and 20 breaths per minute. 70.9% of patients would have had a change of treatment during their admission based on the UK's National Early Warning System if EMRR was used in place of VMRR. An elevated EMRR was predictive of hypoxic (hazard ratio: 1.8 (1.05-3.07)) and pyrexic (hazard ratio: 9.7 (3.8-25)) episodes over the following 12 h.Continuous EMRR values are systematically different to VMRR values, and results suggest it is a better indicator of true RR as it has lower kurtosis, higher variance, a lack of peaks at expected values (18 and 20) and it measures a physiological component of breathing directly (abdominal movement). Results suggest EMRR is a strong marker of oncoming hypoxia and is highly predictive of oncoming pyrexic events in the following 12 h. In many diseases, this could provide an early window to escalate care prior to deterioration, potentially preventing morbidity and mortality.
呼吸频率（RR）通常用于监测传染病、心脏病和呼吸系统疾病患者，也是用于预测患者病情恶化的预警评分的组成部分。然而，它通常是通过视觉观察来测量的，存在相当大的偏差和不准确性。首先，比较电子测量 RR（EMRR）和视觉测量 RR（VMRR）的分布和准确性。其次，确定电子连续 RR 监测是否可以预测传染病性呼吸疾病即将发生的缺氧和发热事件，以及提前多久可以预测。
使用大型三级医院的患者数据进行了一项回顾性队列研究，分析 EMRR 和 VMRR 之间的差异。使用 Cox 比例风险模型确定连续 EMRR 测量是否可以预测即将发生的缺氧（SpO<92%）和发热（体温>38°C）事件。
数据来自 34 例 COVID-19 患者，共收集了 3445 次 VMRR（独立于霍桑效应）、外周血氧饱和度和体温以及 729117 次 EMRR 测量值。VMRR 的分布峰值在 18 和 20 次/分钟。如果使用 EMRR 代替 VMRR，70.9%的患者在住院期间将根据英国国家早期预警系统进行治疗改变。升高的 EMRR 可预测 12 小时内出现缺氧（危险比：1.8（1.05-3.07））和发热（危险比：9.7（3.8-25））事件。
连续 EMRR 值与 VMRR 值系统不同，结果表明它是真实 RR 的更好指标，因为它具有较低的峰度、较高的方差、缺乏预期值（18 和 20）的峰值，并且直接测量呼吸的生理成分（腹部运动）。结果表明，EMRR 是即将发生缺氧的有力标志物，对 12 小时内即将发生的发热事件具有高度预测性。在许多疾病中，这可以提供一个早期的窗口，以便在病情恶化之前升级护理，从而潜在地预防发病率和死亡率。
