Changes in pulse transit time according to target controlled infusion of propofol versus sevoflurane inhalation induction

Youn, Ann Misun; Shin, Yong Sup; Park, Sang Il

Abstract

BACKGROUND
Pulse transit time (PTT), the time it takes a pulse wave to travel from one arterial site to another, is a noninvasive indicator of arterial stiffness. The main objective of our study was to compare two common anesthetic techniques using PTT in order to explore which technique would bring more vascular distention.
METHODS
Sixty female patients, ages 18-65, classified by ASA 1 or 2 undergoing general anesthesia, were randomly allocated into two groups, S and P. Group S (n = 30) was inducted with 2 mg/kg of propofol and remifentanil 5.0 ng/ml. Group P (n = 30) was inducted with propofol 4.0 ug/ml and remifentanil 4.0 ng/ml using a target controlled infusion (TCI) pump. Group S was anesthetically maintained with sevoflurane at 1.0 MAC and 1.0 ng/ml remifentanil while group P was anesthetically maintained with propofol 3.0 ug/ml and remifentanil 1.0 ng/ml for 10 minutes. PTT values were obtained by measuring the distance between the electrocardiographic R wave, which approximates the opening of the aortic valve, to the radial artery. Three consecutive values of prePTT, postPTT, and corresponding vital signs were measured and recorded before and 10 minutes after anesthetic induction.
RESULTS
PrePTT in group S and group P was 240.18 +/- 3.66 and 239.32 +/- 3.69 ms, respectively. Ten minutes after anesthetic induction, postPTT in group S increased to 284.16 +/- 4.37 ms while postPTT in group P increased to 278.7 +/- 4.53 ms (P > 0.05). However, despite the slope of group S (43.98 +/- 22.18) being greater than group P (39.38 +/- 18.39), the difference between the two groups was statistically insignificant (P = 0.2239).
CONCLUSIONS
Changes in PTT values were statistically insignificant regarding arterial distension in patients anesthetized with target controlled infusion of propofol compared to those with balanced anesthesia with sevoflurane.