Figure 1
From: Heart rate variability in the early resuscitation of septic shock
Heart rate variability parameters measured during the initial resuscitation of patients with septic shock. Nonsurvivors showed significantly impaired variability as measured by LF and the HF/LF ratio. Data presented as logarithmic transformation to control for scale and allow visual comparison. Differences between survivors and nonsurvivors were calculated using raw averages without logarithmic conversion. Time domain factors: SDNN = standard deviation of the normal R-R interval; RMSSD = root mean square of the difference of successive R-R intervals. Frequency domain factors of HRV spectrum: LF = low frequency (0.04 to 0.15 Hz); HF = high frequency (0.18 to 0.4 Hz).