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Effect of thoracic epidural anesthesia on heart rate variability in a porcine model

View Article: PubMed Central - PubMed

ABSTRACT

Heart rate variability (HRV) is increasingly recognized as a means of evaluating autonomic tone. Thoracic epidural anesthesia (TEA) has been previously demonstrated to suppress the electrical storms in patients. However, the effect of TEA on HRV during sympathoexcitation remains unknown. In this study, we aimed to determine the effects of TEA on HRV response to left stellate ganglion stimulation (LSS) in a porcine model. In 12 anesthetized pigs after insertion of an epidural catheter to T1 level, a median sternotomy was performed to expose the heart and the left stellate ganglion. A 56‐electrode sock was used for obtaining epicardial activation recovery interval (ARI). Animal received LSS at 4 Hz for 30 sec. After 30 min of bupivacaine epidural injection, LSS was performed in the same way as the baseline condition. LSS significantly increased low‐frequency normalized units (LF: 44.9 ± 6.7 vs. 13.6 ± 3.1 msec2 baseline, P < 0.05) and decreased high‐frequency normalized units (HF: 11.5 ± 4.6 vs. 41.9 ± 5.1 msec2 baseline, P < 0.05). As a result, LF/HF significantly increased from 0.3 ± 0.2 to 3.9 ± 1.4 during LSS. TEA significantly attenuated the LF/HF from 3.9 ± 1.4 to 1.6 ± 0.8 with increased HF components from 11.5 ± 4.6 to 26.5 ± 3.2 msec2. LF component significantly correlates with global ARI (r = −0.81) and dispersion of repolarization (r = 0.85). HRV can precisely reflect the cardiac autonomic tone and TEA modulates the HRV by enhancing the HF components probably through a parasympathetic nerve system.

No MeSH data available.


Correlation between low‐frequency component (LF) of heart rate variability and activation recovery interval (ARI) and DOR (dispersion of repolarization).
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phy213116-fig-0005: Correlation between low‐frequency component (LF) of heart rate variability and activation recovery interval (ARI) and DOR (dispersion of repolarization).

Mentions: LSS significantly shortened ARI from 423 ± 18 to 387 ± 21 msec and increased the ARI dispersion from 501 ± 26 to 1753 ± 56 msec2 (P < 0.05). Table 1 and Figure 5 show that percentage change from baseline during LSS in LF component closely correlates with the percentage change in ARI (r = −0.81, P < 0.001) and ARI dispersions (r = 0.85, P < 0.001). However, the percentage change in HF and LF/HF do not have a significant correlation with changes in ARI and DOR during LSS.


Effect of thoracic epidural anesthesia on heart rate variability in a porcine model
Correlation between low‐frequency component (LF) of heart rate variability and activation recovery interval (ARI) and DOR (dispersion of repolarization).
© Copyright Policy - creativeCommonsBy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5392501&req=5

phy213116-fig-0005: Correlation between low‐frequency component (LF) of heart rate variability and activation recovery interval (ARI) and DOR (dispersion of repolarization).
Mentions: LSS significantly shortened ARI from 423 ± 18 to 387 ± 21 msec and increased the ARI dispersion from 501 ± 26 to 1753 ± 56 msec2 (P < 0.05). Table 1 and Figure 5 show that percentage change from baseline during LSS in LF component closely correlates with the percentage change in ARI (r = −0.81, P < 0.001) and ARI dispersions (r = 0.85, P < 0.001). However, the percentage change in HF and LF/HF do not have a significant correlation with changes in ARI and DOR during LSS.

View Article: PubMed Central - PubMed

ABSTRACT

Heart rate variability (HRV) is increasingly recognized as a means of evaluating autonomic tone. Thoracic epidural anesthesia (TEA) has been previously demonstrated to suppress the electrical storms in patients. However, the effect of TEA on HRV during sympathoexcitation remains unknown. In this study, we aimed to determine the effects of TEA on HRV response to left stellate ganglion stimulation (LSS) in a porcine model. In 12 anesthetized pigs after insertion of an epidural catheter to T1 level, a median sternotomy was performed to expose the heart and the left stellate ganglion. A 56&#8208;electrode sock was used for obtaining epicardial activation recovery interval (ARI). Animal received LSS at 4&nbsp;Hz for 30&nbsp;sec. After 30&nbsp;min of bupivacaine epidural injection, LSS was performed in the same way as the baseline condition. LSS significantly increased low&#8208;frequency normalized units (LF: 44.9&nbsp;&plusmn;&nbsp;6.7 vs. 13.6&nbsp;&plusmn;&nbsp;3.1&nbsp;msec2 baseline, P&nbsp;&lt;&nbsp;0.05) and decreased high&#8208;frequency normalized units (HF: 11.5&nbsp;&plusmn;&nbsp;4.6 vs. 41.9&nbsp;&plusmn;&nbsp;5.1&nbsp;msec2 baseline, P&nbsp;&lt;&nbsp;0.05). As a result, LF/HF significantly increased from 0.3&nbsp;&plusmn;&nbsp;0.2 to 3.9&nbsp;&plusmn;&nbsp;1.4 during LSS. TEA significantly attenuated the LF/HF from 3.9&nbsp;&plusmn;&nbsp;1.4 to 1.6&nbsp;&plusmn;&nbsp;0.8 with increased HF components from 11.5&nbsp;&plusmn;&nbsp;4.6 to 26.5&nbsp;&plusmn;&nbsp;3.2&nbsp;msec2. LF component significantly correlates with global ARI (r&nbsp;=&nbsp;&minus;0.81) and dispersion of repolarization (r&nbsp;=&nbsp;0.85). HRV can precisely reflect the cardiac autonomic tone and TEA modulates the HRV by enhancing the HF components probably through a parasympathetic nerve system.

No MeSH data available.