Instantaneous Time Course of the Autonomic Cardiovascular and Respiratory Response of Healthy Subjects to Hypoglycemic Stimulus

In 13 healthy subjects we assessed the effect of hypoglycemia (HG) provoked by insulin on: R-R intervals (RR), systolic pressure (SP), diastolic pressure (DP), pulse pressure (PP), respiratory frequency (RF) and tidal volume (V T ) 5-min time series; the instantaneous time courses of their low-frequency (LF RR , LF SP , LF DP , LF PP ), high-frequency (HF RR , HF Res ) powers and their respective central frequencies (cfLF RR , cfLF SP , cfLF DP , cfLF PP ), computed by a time-frequency distribution; instantaneous baroreflex (BRS) and respiratory sinus arrhythmia sensitivities (RSAS), obtained by alpha index, and their coherences (cBRS and cRSAS) by cross time-frequency analysis. Peak HG (2.7±0.3 mmol/l) induced: 1) decreases (p