Objective To study both non-invasive continuous cardiac index (CCI) and risk factors of coronary heart disease related with left ventricular ejection fraction (LVEF). Methods Retrospective study was done at VIP Health Center with 90 patients with preanesthesia assessment for gastrointestinal endoscopy under intravenous anesthesia between January and March 2022 in our hospital. CCI was measured using non-invasive real-time arterial blood pressure and hemodynamic monitoring system. Risk factors of coronary heart disease were collected. There were three groups of patients according to the results of LVEF gotten from echocardiography examination including group of LVEF 40%-49% (n=15), group of LVEF 50%-59% (n=38) and group of LVEF >60% (n=37). Results The group of LVEF 40%-49% had the highest rate of smoking (60.0%), hypertension (80.0%), diabetes (73.3%), hyperlipidemia (86.6%), obesity (53.3%), family history of early onest cardiovascular disease (33.3%) and the highest rate of ≥3 risk factors of coronary heart disease (80.0%)(P<0.05). The CCI in the group of LVEF 40%-49% was the lowest among three groups (P<0.05). There was a significant positive correlation between CCI and LVEF (r>0.95, P<0.05). Conclusions It was suggested that non-invasive real-time arterial blood pressure and hemodynamic monitoring system could be used for preanesthesia assessment, and CCI related to LVEF, which improves the safety of anesthesia for patients.

Objective The purpose of this study was to compare the three techniques: medium-flow, low-flow and low-flow with BIS monitoring, for sevoflurane anaesthesia in terms of consumption of sevoflurane, recovery from anaesthesia, awakening time and side effects. Methods Ninety-six ASA Ⅰ - Ⅱ aged 27-51 yr undergoing elective surgery on low abdominal or low extremities under general anaesthesia were randomly divided into three groups: group A medium flow (FGF 1000 ml?min-1 ), group B low flow (FGF 500 ml?min-1 ) and group C low flow ( FGF 500 ml? min-1 ) with BIS monitoring. Sevoflurane was delivered into the circuit system from a Komesarroff vaporizer placed in-circle on the inspiration limb. In groups A and B the concentration of sevoflurane delivered was adjusted according to clinical signs of anesthesia, while in group C according to the BIS value (at 46 ?10). Before induction of anesthesia the patient was denitrogenated for 3 min with high flow rate of oxygen (6 L ?min-1 ). Anesthesia was induced with midazolam 0.03 mg?kg-1 , fentanyl 1 ?g?kg-1 , propofol 2 mg?kg-1 and vecuronium 0.1 mg?kg-1. After intubation, the patient was mechanically ventilated and PaCO2 was maintained at 35 - 45 mm Hg. Anesthesia was maintained with sevoflurane. The consumption of sevoflurane was calculated from deduction of the volume of sevoflurane left in the vaporizer from 30ml of sevoflurane added initially into the vaporizer. The duration from termination of sevoflurane administration to eye-opening and orientation and the incidence of nausea and vomiting were recorded. Results During surgery the end-tidal sevoflurane concentrations were maintained at (1.40?0.20) MAC (in group A), (1.10? 0.20) MAC (in group B) and (0.80?0.20) MAC (in group C) respectively. The volume of sevoflurane consumed was (13.3 ? 1.6) ml?h-1 (group A), (9.6 ?1.5 ) ml ? h ( group B) and (7.5?1.8)ml?h-1( group C) respectively. The time to regain consciousness were (14.3?3.3) min (group A), (10.5 ? 2.8) min (group B) and (7.5?2.6) min (group C). The times to full orientation were (24.5?6.1) min (group A), (17.4?5.5) min (group B) and (12.7 ? 4.8) min (group C). The incidence of nausea and vomiting was 14.5 % ? 2.6 % (group A), 10.1 % ?2.3 % (group B) and 7.5 % ?2.1 % (group C) . Conclusion Low-flow closed circuit anaesthesia combined with BIS monitoring has the advantages of least sevoflurane consumed, fastest recovery and least incidence of nausea and vomiting and is the best technique for sevoflurane anaesthesia.