Response of Arterial Mechanical Impedance to Different Concentrations of Remifentanil during Abdominal Laparoscopic Colectomy

Sukhdorj Elbegzaya

Nakamura Ryuji

Saeki Noboru

Yanabe Kensuke

Hirano Hiroki

Hirano Harutoyo

Yoshizumi Masao

Tsuji Toshio

Kawamoto Masashi

Hiroshima Journal of Medical Sciences

[PISSN] 0018-2052

[EISSN] 2433-7668

[NCID] AA00664312

A specific and reliable method for monitoring analgesia during general anesthesia is urgently required. Previously, we introduced a method that indicates arterial mechanical properties for estimating arterial wall stiffness (K). However, whether the response of K actually indicates changes in remifentanil target concentrations under continuous surgical stress, is unclear. Thus, we aimed to evaluate how K responds to different remifentanil target concentrations.
This prospective study enrolled 30 patients who underwent laparoscopic colectomy. The patients received 3 different effect-site concentrations (2, 4, and 6 ng/ml) of remifentanil 3 times during the study period. The K values at 4-ng/ml administration were used as control values (Kcontrol). K values at 6-ng/ml administration (K6ng) and those at 2-ng/ml administration (K2ng) were normalized by dividing them by the control values. The results showed that K responded to the changes in remifentanil concentration, significantly decreasing at 6-ng/ml remifentanil effect-site concentration and increasing at 2-ng/ml concentration. The stress response at low analgesia was higher than that at high analgesia, and, as predicted, normalized K2ng was significantly greater than normalized K6ng. In conclusion, we found that K is a sensitive stress response monitor and dynamically responds to changes in remifentanil concentration in invasive stimulation during laparoscopic colectomy.

Photoplethysmogram

Anesthesia

Nociceptive reflex

Medical sciences [ 490 ]

eng

Hiroshima University Medical Press

Copyright (c) 2018 Hiroshima University Medical Press

[ISSN] 0018-2052

[ISSN] 2433-7668

[NCID] AA00664312

[DOI] 10.24811/hjms.67.3_55

[DOI] https://doi.org/10.24811/hjms.67.3_55