Thames Valley Air Ambulance, Stokenchurch House, Oxford Road, Stokenchurch, HP14 3SX, Buckinghamshire, UK.
Frimley Health NHS Foundation Trust, Camberley, Surrey, UK.
Scand J Trauma Resusc Emerg Med. 2024 Aug 27;32(1):77. doi: 10.1186/s13049-024-01240-y.
Blood pressure monitoring is important in the pre-hospital management of critically ill patients. Non-invasive blood pressure (NIBP) measurements are commonly used but the accuracy of standard oscillometric cuff devices may be affected by extremes of physiology and adverse conditions (e.g. vibration) during transport. This study aimed to quantify the accuracy of NIBP measurements amongst patients requiring pre-hospital critical care.
A retrospective cohort study was undertaken using data from patients treated by a pre-hospital critical team between 1st May 2020 and 30th April 2023 that had NIBP measured concurrently with invasive blood pressure (IBP) arterial manometry. An acceptable difference was determined a priori to be < 20mmHg for systolic blood pressure (SBP) and diastolic blood pressure (DBP), and < 10mmHg for mean arterial pressure (MAP). The primary outcome was "pairwise agreement", i.e. the proportion of paired observations that fell within this range of acceptability. Bland-Altman plots were constructed together with 95% limits of agreement to visualise differences between pairs of data. Associations with patient age, reason for critical care, transport status, haemodynamic shock, severe hypertension, and arterial catheter position were explored in univariate analyses and by fitting multivariable logistic regression models.
There were 2,359 paired measurements from 221 individual patients with a median age of 57. The most frequent reason for transport was cardiac arrest (79, 35.7%). Bland-Altman analyses suggested unacceptably wide limits of agreement with NIBP overestimating both SBP and MAP during hypotension and underestimating these values during hypertension. Haemodynamic shock (SBP < 90mmHg) was independently associated with reduced pairwise agreement for SBP (adjusted odds ratio [aOR] 0.52, 95% CI 0.35 to 0.77), DBP (aOR 0.65, 95% CI 0.42 to 0.99) and MAP (aOR 0.53, 95% CI 0.36 to 0.78) and severe hypertension (SBP > 160mmHg) with reduced pairwise agreement for SBP (aOR 0.17, 95% CI 0.11 to 0.27). There was no association between patient transport and agreement between the methods for SBP, DBP, or MAP.
Non-invasive blood pressure measurements are often inaccurate in the pre-hospital critical care setting, particularly in patients with haemodynamic instability. Clinicians should be cautious when interpreting NIBP measurements and consider direct arterial pressure monitoring when circumstances allow.
血压监测对于危重症患者的院前管理至关重要。非侵入性血压（NIBP）测量通常用于临床，但在转运过程中，标准振动脉冲袖带设备的准确性可能会受到生理极限和不利条件（例如振动）的影响。本研究旨在量化需要院前重症监护的患者中 NIBP 测量的准确性。
采用回顾性队列研究方法，使用 2020 年 5 月 1 日至 2023 年 4 月 30 日期间由院前重症监护团队治疗的患者的数据，这些患者同时进行了 NIBP 和有创动脉血压（IBP）动脉测压。预先确定可接受的差异为收缩压（SBP）和舒张压（DBP）<20mmHg，平均动脉压（MAP）<10mmHg。主要结局为“配对一致性”，即落在可接受范围的配对观察结果的比例。通过构建 Bland-Altman 图并结合 95%一致性界限，可视化了数据对之间的差异。在单变量分析和拟合多变量逻辑回归模型中，探讨了患者年龄、重症监护原因、转运状态、血流动力学休克、严重高血压和动脉导管位置与配对一致性的关系。
共有 221 名患者的 2359 对测量值，中位年龄为 57 岁。最常见的转运原因是心脏骤停（79 例，35.7%）。Bland-Altman 分析表明，在低血压期间，NIBP 对 SBP 和 MAP 的估计值超出了可接受范围，而在高血压期间，NIBP 对这些值的估计值偏低。血流动力学休克（SBP<90mmHg）与 SBP（调整后的优势比[OR]0.52，95%CI0.35 至 0.77）、DBP（OR0.65，95%CI0.42 至 0.99）和 MAP（OR0.53，95%CI0.36 至 0.78）的配对一致性降低相关，严重高血压（SBP>160mmHg）与 SBP（OR0.17，95%CI0.11 至 0.27）的配对一致性降低相关。患者转运与 SBP、DBP 或 MAP 之间方法的一致性之间无关联。
非侵入性血压测量在院前重症监护环境中通常不准确，尤其是在血流动力学不稳定的患者中。临床医生在解释 NIBP 测量值时应谨慎，并在情况允许时考虑直接动脉血压监测。
