Patnaik Rohit, Krishna Bhuvana, Sampath Sriram
Critical Care Medicine, Institute of Medical Sciences and SUM Hospital, Bhubaneswar, IND.
Critical Care Medicine, St. John's Medical College and Hospital, Bengaluru, IND.
Cureus. 2023 Jun 10;15(6):e40229. doi: 10.7759/cureus.40229. eCollection 2023 Jun.
Introduction The passive leg raising (PLR) test is a simple, non-invasive method of knowing fluid responsiveness by acting as an internal-fluid challenge. The PLR test coupled with a non-invasive assessment of stroke volume would be the ideal method to assess fluid responsiveness. This study aimed to determine the correlation between transthoracic echocardiographic cardiac output (TTE-CO) and common carotid artery blood flow (CCABF) parameters in determining fluid responsiveness with the PLR test. Methods We performed a prospective observational study on 40 critically ill patients. Patients were evaluated with a 7-13 MHz linear transducer probe for CCABF parameters calculated using time-averaged mean velocity (TAmean) and with a 1-5 MHz cardiac probe equipped with tissue doppler imaging (TDI) for TTE-CO calculated using left ventricular outflow tract velocity time integral (LVOT VTI) with an apical five-chamber view. Two separate PLR tests (five minutes apart) were done within 48 hours of ICU admission. The first PLR test was to assess the effects on TTE-CO. The second PLR test was performed to assess the effects on CCABF parameters. Patients were designated as fluid responders (FR) if changes in TTE-CO (Δ TTE-CO) ≥ 10 %. Results A positive PLR test was observed in 33% of patients. A strong correlation was present between absolute values of TTE-CO calculated using LVOT VTI and the absolute values of CCABF calculated using TAmean (r=0.60, p<0.05). However, a weak correlation was found between Δ TTE-CO and changes in CCABF (Δ CCABF) during the PLR test (r=0.05, p<0.74). A positive PLR test response could not be detected by Δ CCABF (area under the curve (AUC): 0.59 ± 0.09). Conclusions We found a moderate correlation between TTE-CO and CCABF at baseline. However, Δ TTE-CO had a very poor correlation with Δ CCABF, during the PLR test. Considering this, CCABF parameters may not be recommended as a means to detect fluid responsiveness with PLR tests in critically ill patients.
引言 被动抬腿（PLR）试验是一种通过模拟体内液体负荷试验来了解液体反应性的简单、非侵入性方法。将PLR试验与每搏输出量的非侵入性评估相结合，将是评估液体反应性的理想方法。本研究旨在确定经胸超声心动图心输出量（TTE-CO）与颈总动脉血流（CCABF）参数在PLR试验中测定液体反应性方面的相关性。方法 我们对40例危重症患者进行了一项前瞻性观察性研究。使用7-13MHz线性换能器探头评估患者的CCABF参数，该参数通过时间平均平均速度（TAmean）计算得出；使用配备组织多普勒成像（TDI）的1-5MHz心脏探头，通过心尖五腔视图下的左心室流出道速度时间积分（LVOT VTI）计算TTE-CO。在入住重症监护病房（ICU）的48小时内进行两次单独的PLR试验（间隔5分钟）。第一次PLR试验用于评估对TTE-CO的影响。第二次PLR试验用于评估对CCABF参数的影响。如果TTE-CO变化（ΔTTE-CO）≥10%，则将患者指定为液体反应者（FR）。结果 33%的患者PLR试验呈阳性。使用LVOT VTI计算的TTE-CO绝对值与使用TAmean计算的CCABF绝对值之间存在强相关性（r=0.60，p<0.05）。然而，在PLR试验期间，ΔTTE-CO与CCABF变化（ΔCCABF）之间的相关性较弱（r=0.05，p<0.74）。通过ΔCCABF无法检测到阳性PLR试验反应（曲线下面积（AUC）：0.59±0.09）。结论 我们发现基线时TTE-CO与CCABF之间存在中度相关性。然而，在PLR试验期间，ΔTTE-CO与ΔCCABF的相关性非常差。考虑到这一点，在危重症患者中，不建议将CCABF参数作为检测PLR试验液体反应性的手段。
