Abstract: Objective To compare the safety of propofol fentanyl and midazolam fentanyl for gastrointestinal endoscopy in patients with advanced liver disease. 
Methods A total of 86 patients with advanced liver disease who underwent gastrointestinal endoscopy due to cirrhosis were recruited. All patients underwent upper gastrointestinal endoscopy examination. Patients were divided into propofol fentanyl group (n=43) and midazolam fentanyl group (n=43), according to the anesthesia medications. The propofol fentanyl group received intravenous propofol 2 mg/kg and fentanyl 0.5 μg/kg, while the midazolam fentanyl group received intravenous midazolam 3 mg and fentanyl 0.5 μg/kg. Changes in hemodynamic parameters ［oxygen saturation (SpO2), heart rate (HR), mean arterial pressure (MAP)］ before induction (T0), at 5 min after sedation (T1), 10 min after sedation (T2), 15 min after sedation (T3), 30 min after sedation (T4), and at 5 min before surgery (T5). The Ramsay sedation scores at T0 to T5 were compared. The bispectral index (BIS) values, and postoperative electroencephalogram (EEG) θ wave and δ wave band frequency before surgery, before anesthesia induction, before tracheal intubation and after surgery were compared. The occurrence of adverse reactions during surgery among the subjects was compared. 
Results The SpO2 levels in the two groups showed a gradual upward trend, while the HR levels showed a gradual downward trend. The increase in SpO2 levels in the propofol fentanyl group was greater than that in the midazolam fentanyl group, while the decrease in HR level was greater than that in the midazolam fentanyl group. There were statistically significant difference in the interaction between groups, time points, and time points between groups (P＜0.05). The Ramsay sedation scores and EEG δ wave band showed a trend of initial increasing and then decreasing in the two groups, while BIS and EEG θ wave band showed a trend of initial decreasing and then increasing. The Ramsay sedation score, BIS, and fluctuation amplitude of EEG θ wave band, EEG δ wave band were greater in the propofol fentanyl group than in the midazolam fentanyl group, and there were statistically significant difference in the interaction between groups, time points, and time points between groups (P＜0.05). The incidence of hypotension in the propofol fentanyl group was higher than that in the midazolam fentanyl group (P＜0.05). 
Conclusion Propofol or midazolam in combination with fentanyl is effective in sedating patients with advanced liver disease undergoing upper gastrointestinal endoscopy. Compared with midazolam, propofol can better exert effects of deep sedation, which is reflected in a decrease in BIS and an increase in EEG δ wave band frequency. However, it increases the risk of hypotension. 

Key words: end-stage liver disease, endoscopy, propofol, midazolam