From the Division of Trauma, Emergency Surgery, and Surgical Critical Care, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
J Trauma Acute Care Surg. 2013 Oct;75(4):607-12. doi: 10.1097/TA.0b013e31829bb991.
Heart rate complexity (HRC), commonly described as a "new vital sign," has shown promise in predicting injury severity, but its use in clinical practice has been precluded by the absence of real-time data. This study was conducted to evaluate the utility of real-time, automated, instantaneous, hand-held heart rate entropy analysis in predicting the need for lifesaving interventions (LSIs). We hypothesized that real-time HRC would predict LSIs.
Prospective enrollment of patients who met criteria for trauma team activation was conducted at a Level I trauma center (September 2011 to February 2012). A novel, hand-held, portable device was used to measure HRC (by sample entropy) and time-domain heart rate variability continuously in real time for 2 hours after the moment of presentation. Electric impedance cardiography was used to determine cardiac output. Patients who received an LSI were compared with patients without any intervention (non-LSI). Multivariable analysis was performed to control for differences between the groups.
Of 82 patients enrolled, 21 (26%) received 67 LSIs within 24 hours of hospital arrival. Initial systolic blood pressure was similar in both groups. LSI patients had a lower Glasgow Coma Scale (GCS) score (9.2 [5.1] vs. 14.9 [0.2], p < 0.0001). The mean (SD) HRC value on presentation was 0.8 (0.6) in the LSI group compared with 1.5 (0.6) in the non-LSI group (p < 0.0001). With the use of logistic regression, initial HRC was the only significant predictor of LSI. A cutoff value for HRC of 1.1 yields sensitivity, specificity, negative predictive value, and positive predictive value of 86%, 74%, 94%, and 53%, respectively, with an accuracy of 77% for predicting an LSI.
Decreased HRC on hospital arrival is an independent predictor of the need for LSI in trauma activation patients. Real-time HRC may be a useful adjunct to standard vital signs monitoring and predicts LSIs.
Prognostic and diagnostic study, level III.
心率复杂度（HRC）通常被描述为“新的生命体征”，已显示出在预测损伤严重程度方面的潜力，但由于缺乏实时数据，其在临床实践中的应用受到限制。本研究旨在评估实时、自动、即时、手持式心率熵分析在预测需要救生干预（LSI）方面的效用。我们假设实时 HRC 将预测 LSI。
在一级创伤中心（2011 年 9 月至 2012 年 2 月）进行符合创伤小组激活标准的患者前瞻性入组。使用新型手持式便携式设备连续实时测量 2 小时内 HRC（通过样本熵）和时域心率变异性。使用电抗心图法确定心输出量。接受 LSI 的患者与未接受任何干预的患者（非 LSI）进行比较。进行多变量分析以控制组间差异。
82 名入组患者中，21 名（26%）在入院后 24 小时内接受了 67 次 LSI。两组患者的初始收缩压相似。LSI 患者的格拉斯哥昏迷评分（GCS）较低（9.2 [5.1] vs. 14.9 [0.2]，p < 0.0001）。LSI 组患者就诊时的平均（SD）HRC 值为 0.8（0.6），而非 LSI 组为 1.5（0.6）（p < 0.0001）。使用逻辑回归，初始 HRC 是 LSI 的唯一显著预测因素。HRC 的截断值为 1.1 时，预测 LSI 的灵敏度、特异性、阴性预测值和阳性预测值分别为 86%、74%、94%和 53%，准确性为 77%。
入院时 HRC 降低是创伤激活患者需要 LSI 的独立预测因素。实时 HRC 可能是标准生命体征监测的有用辅助手段，并可预测 LSI。
预后和诊断研究，III 级。
