TY - JOUR
T1 - Heart rate variability and arterial oxygen saturation response during extreme normobaric hypoxia
AU - Botek, Michal
AU - Krejci, Jakub
AU - De Smet, Stefan
AU - Gaba, Ales
AU - MCKUNE, Andrew
PY - 2015
Y1 - 2015
N2 - The primary purpose of this study was to assess the response of autonomic cardiac activity and changes in the arterial oxygen saturation (SpO2) during normobaric hypoxia and subsequent recovery. Heart rate variability (HRV) and SpO2 were monitored in a supine position during hypoxia (FiO2=9.6%) for 10min, and normoxic recovery in 29 subjects. Spectral analysis of HRV quantified the autonomic cardiac activity by means of low frequency (LF) (0.05-0.15Hz) and high frequency (HF) (0.15-0.50Hz) power transformed by natural logarithm (Ln). Based on the SpO2 response to hypoxia, the subjects were divided into Resistant (RG, SpO2=80.8±7.0%) or Sensitive (SG, SpO2=67.2±2.9%) group. The SpO2 and vagal activity (LnHF) significantly decreased during hypoxia in both groups. A withdrawal in vagal activity was significantly greater in SG compared to RG. Moreover, only in SG, a relative increase in sympathetic modulation (Ln LF/HF) during hypoxia occurred. Correlations (r=-0.461, and r=0.595, both P<0.05) between δSpO2 (delta) and δLn LF/HF, and δLnHF were found. Based on results, it seems that SpO2 level could be an important factor that influences the autonomic cardiac response in hypoxia.
AB - The primary purpose of this study was to assess the response of autonomic cardiac activity and changes in the arterial oxygen saturation (SpO2) during normobaric hypoxia and subsequent recovery. Heart rate variability (HRV) and SpO2 were monitored in a supine position during hypoxia (FiO2=9.6%) for 10min, and normoxic recovery in 29 subjects. Spectral analysis of HRV quantified the autonomic cardiac activity by means of low frequency (LF) (0.05-0.15Hz) and high frequency (HF) (0.15-0.50Hz) power transformed by natural logarithm (Ln). Based on the SpO2 response to hypoxia, the subjects were divided into Resistant (RG, SpO2=80.8±7.0%) or Sensitive (SG, SpO2=67.2±2.9%) group. The SpO2 and vagal activity (LnHF) significantly decreased during hypoxia in both groups. A withdrawal in vagal activity was significantly greater in SG compared to RG. Moreover, only in SG, a relative increase in sympathetic modulation (Ln LF/HF) during hypoxia occurred. Correlations (r=-0.461, and r=0.595, both P<0.05) between δSpO2 (delta) and δLn LF/HF, and δLnHF were found. Based on results, it seems that SpO2 level could be an important factor that influences the autonomic cardiac response in hypoxia.
KW - Autonomic cardiac regulation
KW - Desaturation
KW - Simulated altitude
KW - Sympathovagal balance
KW - Vagal activity
UR - http://www.scopus.com/inward/record.url?scp=84930083136&partnerID=8YFLogxK
UR - http://www.mendeley.com/research/heart-rate-variability-arterial-oxygen-saturation-response-during-extreme-normobaric-hypoxia
U2 - 10.1016/j.autneu.2015.04.001
DO - 10.1016/j.autneu.2015.04.001
M3 - Article
SN - 1566-0702
VL - 190
SP - 40
EP - 45
JO - Autonomic Neuroscience: Basic and Clinical
JF - Autonomic Neuroscience: Basic and Clinical
IS - 10
ER -