Effect of fentanyl on heart rate variability during spontaneous and paced breathing in healthy volunteers.
BACKGROUND
Many studies have been conducted to assess the effects of fentanyl on the autonomic nervous system (ANS) by heart rate variability (HRV) analysis, but disagreement on the results is still present due to confounding influences introduced by concomitant administration of other drugs or opioid-related transitory respiratory depression. We performed a single-drug controlled-breathing study on healthy volunteers to assess the impact of fentanyl on ANS.


METHODS
HRV as a measure of sympathovagal balance was prospectively analyzed with an autoregressive model in 11 subjects during spontaneous and paced breathing (PB) at 20 breaths/min both before and after fentanyl 1 mcg/kg administration. HRV total power, sympathovagal balance (low-frequency/high-frequency ratio) and normalized spectral powers were considered (LFnu, HFnu).


RESULTS
Fentanyl led to a reduction of LFnu (from 55.2+/-23.3 to 43.2+/-24.1, P<0.05) without HFnu increase during PB. A decrease in R-R interval variance (from 3345.6+/-3333.4 to 1806.9+/-1328.6 ms(2), P<0.05) was shown after fentanyl administration during spontaneous but not PB. PB alone decreased the HRV total power and R-R interval variance.


CONCLUSIONS
Low-dose fentanyl administration in healthy volunteers leads to sympathetic and overall ANS modulation decrease, with a trend toward vagal activation.
Vettorello
M
M
Intensive Care Unit Department, Luigi Sacco University Hospital of Milan, Milano, Italy. marco.vettorello@fastwebnet.it
Colombo
R
R
De Grandis
C E
CE
Costantini
E
E
Raimondi
F
F
D000328:Adult; D005260:Female; D005283:Fentanyl / Q000494:pharmacology*; D006262:Health; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012119:Respiration; D013997:Time Factors
D005283:Fentanyl