International Conference on Neurological disorder and Neuroimmunology
Montreal, Canada
Mouhamad Ghyath Jamil
King Faisal Specialist Hospital& Research Center, Saudi Arabia
Title: Heart rate variability and outcomes prediction in critical illness
Biography
Biography: Mouhamad Ghyath Jamil
Abstract
Introduction: Heart rate variability (HRV) is an indicator of the dynamic equilibrium between the sympathetic and parasympathetic divisions of the autonomic nervous system. We hypothesized that baseline HRV variables and changes during resuscitation may predict outcomes from critical illness.
Methods: A prospective, observational study was performed on inpatients that required a rapid response team (RRT)consultation. 24-hour holter monitoring and serial measurements of physiological and biochemical data were made. Heart rate variability was measured as time domains measured over 24 hours (SDNN, ASDNN, rMSSD, pNN50%, SDANN, mean NN) and frequency domains measured hourly (very low frequency- VLF, low frequency- LF, high frequency- HF, low/high ratio). The research ethics committee approved the study protocol (RAC no. 2151069).
Results: 53 patients were enrolled, mean APACHE II score was 23.5±6.3, age 52±24.3 years. Day one SOFA score was 8.9 (range 1, 23). 40 patients (75.5%) required ICU admission; ICU mortality rate was 27.5%. HRV was significantly higher in RRT consultations who stabilized and did not require ICU admission; time domains; ASDNN [33(IQR21) vs. 18(IQR21), p=0.024], rMSDD [23(IQR19) vs. 15(IQR18), p=0.036] and frequency domains; mean VLF [16.6(IQR7.3) vs. 9.3(IQR10), p=0.018],
mean LF [12.4(IQR11) vs. 5.4(IQR7), p=0.009], mean HF [9.3(IQR12) vs. 4.8(IQR7), p=0.011]. Baseline HRV was significantly higher in survivors; ASDNN [31.5(IQR24) vs. 12(IQR9),p=0.002], rMSDD [25(IQR19) vs. 11.5(IQR10), p=0.012], pNN50% [6(IQR9.5) vs. 0.75(IQR2.5), p=0.002], mean NN [732.5(IQR291) vs. 570(IQR87), p=0.006], mean VLF [12.1(IQR11.8) vs. 5.3(IQR4), p=0.002], mean LF [8.5(IQR10.2) vs. 3.4(IQR4.6), p=0.009], mean HF [7.5(IQR6) vs. 3.3(IQR3.9), p=0.005]. Survivors also demonstrated a significantly larger increase in HRV over 24 hours of resuscitation; delta VLF [3(IQR8.1) vs. -0.6(IQR8), p=0.015], delta LF [3.2(IQR5.9) vs. -0.3(IQR7.6), p=0.017].
Conclusion: HRV analysis appears to be a powerful identifier of outcomes in critical illness. Baseline values and changes over the first 24 hours of resuscitation accurately predicted both the need for ICU admission and survival