The Effect of Induction Mode on Various Parameters and Vital Signs during Anesthesia Induction with Propofol Using a Target Contolled Infusion

Kil, Ho Yeong; Lee, Seong Ik; Lee, Seung Joon; Choi, Yeong Hwan; Chae, Bong Soo; Oh, Wan Soo; Kim, Dae Woo

Abstract

BACKGROUND: Anesthesia induction time is related to speed of injection, injected volume, and Keo. In the case of target controlled infusion, induction time can be controlled by adjusting the induction time mode. The aim of this study was to estimate the effect of induction time mode on variable parameters and vital signs during anesthesia induction with propofol using a target controlled infusion (TCI).
METHODS
Sixty unpremedicated adult patients (ASA class I or II, 18 55 yrs) scheduled for elective surgery were randomly allocated to four groups according to induction mode. Group 1 was assigned a flash induction mode, and groups 2, 3 and 4 were assigned 2, 3 and 4min respectively. The end point of anesthesia induction was loss of eyelash reflex. Various parameters including induction time, infused volume, current/effect concentration at induction, and vital signs were compared.
RESULTS
As the induction time mode was prolonged, induction time was delayed, but there was no difference in infused volume. Also, the current concentration decreased gradually, but the effect concentration did not show any difference. The vital signs were more stable in groups 3 and 4 compared with groups 1 and 2.
CONCLUSIONS
For anesthesia induction, a rapid induction mode showed more rapid induction and low current concentration, but vital signs were relatively unstable and the effect concentration at induction showed no difference. For critically ill patients or patients with unstable hemodynamics, a more gradual induction mode for anesthesia induction in propofol TCI is recommended.