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Table 2 Univariate analysis of heart rate variability and complexity indices in associations with the need for life-saving interventions (LSI) amongst trauma patients

From: Development of a heart rate variability and complexity model in predicting the need for life-saving interventions amongst trauma patients

 

LSI (n = 49)

Non-LSI (n = 176)

P value

Heart rate variability time domain analysis

 aRR (mean ± SD)

704.58 ± 166.48

746.76 ± 141.49

0.302

 sdRR (mean ± SD)

30.86 ± 31.20

34.71 ± 28.55

0.982

 avHR (median, IQR)

97.33, 85.59–122.96

88.96, 83.47–96.40

0.029

 sdHR (median, IQR)

2.03, 1.71–3.32

3.08, 1.88–4.53

0.899

 RMSSD (mean ± SD)

17.03 ± 26.46

35.12 ± 148.41

0.278

 NN50 (median, IQR)

0.00, 0.00–2.00

0.00, 0.00–13.75

0.043

 pNN50 (median, IQR)

0.00, 0.00–0.45

0.00, 0.00–3.85

0.051

 TINN (mean ± SD)

122.56 ± 93.47

150.75 ± 137.51

0.399

Heart rate variability frequency domain analysis

 VLF (median, IQR)

58.50, 41.75–218.25

243.00, 132.00–396.00

0.416

 LF ms2 (median, IQR)

15.50, 3.00–217.00

100.00, 60.00–262.00

0.072

 HF ms2 (median, IQR)

4.50, 0.75–25.00

44.00, 21.00–167.00

0.011

 LF norm (median, IQR)

89.05, 67.98–92.90

78.00, 50.30–84.00

0.128

 HF norm (median, IQR)

10.95, 7.03–31.98

21.00, 16.00–49.30

0.128

 LF/HF (median, IQR)

8.11, 3.32–13.26

4.52, 1.02–5.62

0.147

 TP (median, IQR)

76.00, 46.50–504.25

454.00, 275.00–713.00

0.175

Heart rate complexity non-linear analysis

 Poincare plot SD1(mean ± SD)

12.01 ± 18.76

17.49 ± 25.03

0.257

 Poincare plot SD2 (mean ± SD)

41.34 ±  40.65

43.42 ±  31.65

0.545

 Approximate entropy (mean ± SD)

1.00 ± 0.25

1.09 ± 0.15

0.001

 Sample entropy (mean ± SD)

1.13 ± 0.45

1.39 ± 0.38

0.144

 DFA-α1 (mean ± SD)

1.24 ± 0.39

1.12 ± 0.31

0.045

 DFA-α2 (median, IQR)

1.09, 0.93–1.68

1.00, 0.89–1.11

0.027

  1. IQR interquartile range, SD standard deviation, aRR average width of the RR intervals in electrocardiograms, sdRR standard deviation of all RR intervals in electrocardiograms, avHR mean of the instantaneous heart rate in electrocardiograms, sdHR standard deviation of the instantaneous heart rate in electrocardiograms, RMSSD root mean square of differences between adjacent RR intervals in electrocardiograms, NN50 number of consecutive RR intervals differing by more than 50 ms in electrocardiograms, pNN50 percentage of consecutive RR intervals differing by more than 50 ms in electrocardiograms, TINN baseline width of a triangle fit into the RR interval histogram using a least squares technique in electrocardiograms, VLF very low frequency power in electrocardiograms, LF low frequency power in electrocardiograms, HF high frequency power in electrocardiograms, norm normalised, LF/HF ratio of LF power to HF power in electrocardiograms, TP total power derived from variance of all RR intervals in electrocardiograms, DFA detrended fluctuation analysis