Effects of Etco 2 on the Minimum Alveolar Concentration of Sevoflurane that Blunts the Adrenergic Response to Surgical Incision: A Prospective, Randomized, Double-Blinded Trial

Abstract

BACKGROUND: CO 2 has anesthetic potency and effectively influences the circulatory system. We investigated the effects of Etco 2 on the minimum alveolar concentration of sevoflurane that blunts the adrenergic response to surgical incision (MAC-BAR) in patients undergoing radical surgery for gastric carcinoma. METHODS: Ninety patients undergoing radical gastric-carcinoma surgery under general anesthesia were enrolled and randomly assigned into 3 groups. After intubation, the Etco 2 in group L (n = 30), group N (n = 30), and group H (n = 30) was adjusted to 25 mm Hg ≤ Etco 2 <30 mm Hg, 30 mm Hg ≤ Etco 2 < 40 mm Hg, and 40 mm Hg ≤ Etco 2 < 45 mm Hg, respectively, by changes in controlled ventilation. Hemodynamics and depth of anesthesia were observed before and after skin incision. The MAC-BAR of sevoflurane for each group was determined using an up-and-down sequential-allocation technique.

The effect of capnography on the incidence of hypoxia during sedation for EGD and colonoscopy in mildly obese patients: a randomized, controlled study

“…Sedation for endoscopy is becoming increasingly common as a means of diagnosing and treating gastrointestinal diseases, increasing patient comfort and compliance, and improving the efficiency of disease diagnosis and treatment [ 1 ]. However, sedation/anesthesia has high risks, and some complications can cause serious consequences or even death [ 2 , 3 ], such as respiratory depression and hypoxia [ 4 , 5 ].…”

Carbon Dioxide as the Other Therapeutic Carrier Gas?

“…u et al's 1 article seeks to examine whether end-tidal carbon dioxide (Etco 2 ) levels of 40 mm Hg or higher would decrease the "minimum alveolar concentration (MAC) of volatile anesthetic needed to blunt the adrenergic response to surgical incision in 50% of patients (MAC-BAR). "…”

“…Wu et al’s 1 article seeks to examine whether end-tidal carbon dioxide (Et co 2 ) levels of 40 mm Hg or higher would decrease the “minimum alveolar concentration (MAC) of volatile anesthetic needed to blunt the adrenergic response to surgical incision in 50% of patients (MAC-BAR).” In their study, they used sevoflurane and tested 3 groups of patients at 3 different levels at Et co 2 . The first group was between 25 and 30 mm Hg, the second group was between 30 and 40 mm Hg, and the third group was between 40 and 45 mm Hg.…”