Aims
Propofol is the most commonly used intravenous induction anesthetic in clinical practice, but it is associated with several adverse events such as hypoxemia, hypotension, and bradycardia. The use of adjunct medications during gastrointestinal (GI) endoscopy may reduce propofol requirements and improve hemodynamic stability. Esketamine, in particular, has been reported to not only reduce propofol dosage but also counteract its depressive effects, offering enhanced stability and a better anesthetic experience.
This meta-analysis aims to evaluate the effectiveness of esketamine as an adjunct to propofol compared to propofol alone in adults undergoing GI endoscopy.
Methods
A comprehensive search was conducted in MEDLINE, Scopus, Web of Science, and the Cochrane Library to identify eligible randomized controlled trials (RCTs). The primary outcomes assessed were total propofol dosage (mg) and the incidence of hypotension and hypoxemia. Pooled analyses were expressed as mean differences (MDs) for continuous variables and risk ratios (RRs) for categorical outcomes, each with 95% confidence intervals (CIs).
Results
Eight trials met the inclusion criteria. The combination of esketamine and propofol significantly reduced propofol requirements (MD = -54.97; 95% CI: -69.77 to -40.17; p < 0.00001). The combination also lowered the risk of hypotension (RR = 0.28; 95% CI: 0.19–0.40; p < 0.00001) and hypoxemia (RR = 0.58; 95% CI: 0.34–0.98; p = 0.04).
Table 1: Characteristics of the included studies
|
Study ID |
Study design |
Study period |
Operation |
N randomized |
ASA |
Primary outcome(s) |
Key findings |
|
Feng 2022 |
Double-blind RCT |
January 2022 to August 2022 |
Gastrointestinal endoscopy |
100 |
I/II |
EC50 of propofol |
Increasing the dose of esketamine significantly reduces the dose of propofol required for procedures, with fewer hemodynamic changes. |
|
Fu 2024 |
Single-blind RCT |
July 2021 to September 2021 |
Colonoscopy |
100 |
I/II/III |
Incidence of hypotension |
Esketamine + propofol for colonoscopy reduces hypotension and enhances respiration, with satisfactory sedation. |
|
Liu 2023 |
Double-blind RCT |
January 2021 to March 2021 |
Gastroscopy |
80 |
I/II/III |
Total amount of propofol consumption |
Propofol combined with 0.2 mg/kg esketamine reduces total propofol consumption, maintains stable hemodynamics, and does not affect recovery time. |
|
Song 2023 |
Double-blind RCT |
February 2022 to November 2022 |
Bidirectional Endoscopy |
663 |
I/II |
Composite of desaturation and hypotension |
Esketamine reduced desaturation and hypotension by 61%, and decreased propofol usage. |
|
Xiao 2024 |
Double-blind RCT |
November 2022 to February 2023 |
Colonoscopy |
195 |
I/II |
Incidence of hypoxemia, hypotension, hypertension, and bradycardia |
Esketamine + propofol is safe and effective for colonoscopy with fewer complications. |
|
Yang 2021 |
Double-blind RCT |
November 2020 to March 2021 |
Gastrointestinal endoscopy |
90 |
I/II/III |
EC50 of propofol |
Combination reduces propofol EC50, lowers hypotension incidence, and offers shorter recovery with similar satisfaction. |
|
Zhan 2022 |
Double-blind RCT |
November 2020 to September 2021 |
Gastrointestinal endoscopy |
260 |
I/II |
Propofol consumption per minute (mg/min) |
Propofol + 0.2 mg/kg esketamine reduced induction time, cough, and body movement, with lower propofol consumption. No effect on recovery, hemodynamics, or adverse events. |
|
Zheng 2023 |
Double-blind RCT |
August 2022 to February 2023 |
Gastroscopy |
113 |
I/II |
Duration of procedure and propofol consumption |
Propofol + esketamine reduced induction and awakening times, propofol consumption, and incidence of adverse events, with more stable hemodynamics. |
RCT: Randomized control trial, ASA: American Society of Anaesthesiologists criteria for physical status, EC50: median effective concentration
Conclusions
The unique pharmacological properties of esketamine provide substantial value when used in combination with propofol for GI endoscopic procedures, particularly by enhancing hemodynamic stability and reducing propofol requirements.