Propofol Target-controlled Infusion in Anesthesia Induction during Painless Gastroscopy.

Objective: To investigate the feasibility of using the eyelash reflex as an indicator to calculate the individualised optimal target concentration in anesthesia induction during painless gastroscopy.
Study Design: Experimental study.
Place and Duration of Study: China-Japan Union Hospital of Jilin University, China, from January to December in 2016.
Methodology: A total of 180 patients, who were scheduled to receive painless fibergastroscopic examination or treatment in the last three months, were enrolled in this study. All patients were randomly divided into three groups, according to the doctor visiting order (n=60, each). During the induction of anesthesia using propofol target-controlled infusion, the effectsite concentration upon the disappearance of the eyelash reflex (C0) was recorded first. Then, one ug/kg of fentanyl was injected. At the same time, the target effect-site concentration induced by propofol was determined: the effect-site concentration in group A was 1.5 times of C0, the effect-site concentration in group B was two times of C0, and the effectsite concentration in group C was 2.5 times of C0.
Results: During anesthesia induction, the incidence of motor responses was higher in group A than in groups B and C (p<0.05), and the incidence of hypoxemia was significantly higher in group C than in groups A and B (p<0.01).
Conclusion: In the anesthesia option of fentanyl combined with propofol target-controlled infusion, the effect-site concentration of propofol can be set to two times of that at the time the eyelash reflex disappears. This study provides a new pre-assessment method for the induction dose of propofol in painless gastroscopy.