Equivalency between the shock index and subtracting the systolic blood pressure from the heart rate: an observational co
- PDF / 726,750 Bytes
- 8 Pages / 595.276 x 790.866 pts Page_size
- 70 Downloads / 180 Views
(2020) 20:87
RESEARCH ARTICLE
Open Access
Equivalency between the shock index and subtracting the systolic blood pressure from the heart rate: an observational cohort study Yohei Kamikawa1*
and Hiroyuki Hayashi2
Abstract Background: Although the shock index is known to predict mortality and other severe outcomes, deriving it requires complex calculations. Subtracting the systolic blood pressure from the heart rate may produce a simple shock index that would be a clinically useful substitute for the shock index. In this study, we investigated whether the simple shock index was equivalent to the shock index. Methods: This observational cohort study was conducted at 2 tertiary care hospitals. Patients who were transported by ambulance were recruited for this study and were excluded if they were aged < 15 years, had experienced prehospital cardiopulmonary arrest, or had undergone inter-hospital transfer. Pearson’s productmoment correlation coefficient and regression equation were calculated, and two one-sided tests were performed to examine their equivalency. Results: Among 5429 eligible patients, the correlation coefficient between the shock index and simple shock index was extremely high (0.917, 95% confidence interval 0.912 to 0.921, P < .001). The regression equation was estimated as sSI = 258.55 log SI. The two one-sided tests revealed a very strong equivalency between the shock index and the index estimated by the above equation using the simple shock index (mean difference was 0.004, 90% confidence interval 0.003 to 0.005). Conclusion: The simple shock index strongly correlated with the shock index. Keywords: Ambulance, Blood pressure, Cohort study, Critical illness, Heart rate, Shock index, Tertiary care hospital, Vital signs
Background The shock index (SI) is an indicator of the severity of hypovolemic shock and is calculated by dividing the heart rate (HR) by systolic blood pressure (SBP) [1]. It serves to predict the mortality, need for blood transfusion, or necessity of intensive care unit admission * Correspondence: [email protected] 1 Department of Emergency Medicine, University of Fukui Hospital, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193, Japan Full list of author information is available at the end of the article
among patients with trauma [2–7], postpartum haemorrhage [8, 9], acute myocardial infarction [10, 11], stroke [12, 13], sepsis [14, 15], and other critical conditions [16, 17]. Numerous previous studies have demonstrated that the SI demonstrates superior prediction for mortality to traditional vital signs, although it has some limitations, including its low sensitivity especially for the elderly or obstetric patients [2–17]. However, in clinical practice, calculating the SI for all patients is difficult. An SI value > 0.9 is generally accepted as a cut-off point for an increased
© The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution
Data Loading...
