Effect of Low-dose Esketamine Combined With Target-controlled Infusion of Propofol for Painless Gastrointestinal Endoscopy

Efficacy and Safety of Low-dose Esketamine Combined With Target-controlled Infusion of Propofol for Painless Gastrointestinal Endoscopy and Polypectomy

Purpose: 1. To determine the efficacy of low-dose esketamine in painless gastrointestinal endoscopy. 2. To determine the safety of low-dose esketamine in painless gastrointestinal endoscopy. 3. To provide a theoretical basis and new ideas for the application of esketamine as a new drug in perioperative period.

Keeping spontaneous breathing anesthesia can provide patients with comfortable diagnosis and treatment experience during gastrointestinal endoscopy, which is a vital prerequisite for the large-scale development of this operation as well as the early screening and treatment of gastrointestinal malignancies. Clinically, fentanyl combined with propofol is the most commonly used anesthesia regimen for the painless gastroscopy, however its high incidence of respiratory and circulatory depression will threaten the safety of patients. Instead, esketamine has a good action in anesthesia and analgesics, a slighter respiratory depression, as well as with a remarkable improvement in adverse effects than ketamine. What has already been proved is that low- dose of esketamine can remarkably reduce the dosage of propofol during endoscopic retrograde cholangiopancreatography; In our pilot study, we found that not only the incidence of respiratory depression was significantly lower than that of fentanyl during endoscopic polypectomy, but also the dosage of propofol was reduced at the same time,suggesting that esketamine may have a potential superiority in the painless gastrointestinal endoscopy.Our project plans to collect the patients who have received painless gastroscopy and polypectomy in the hospital, and use a target-controlled infusion (TCI) of propofol in combination with esketamine, by observing the total dose of propofol , the time of recovery and the length of hospital stay, the satisfaction of patients and endoscopists, drug side effects,adverse events of respiratory and circulatory system and other indicators ,to evaluate the efficacy and safety of this anesthetic scheme.

Inclusion Criteria:

1. Subject's American Society of Anesthesiologists physical status is I-III.
2. Subject has no symptoms of allergy to anesthetics.
3. Subject has no contraindications for gastrointestinal endoscopy.
4. Subject has given written informed consent to participate.

Exclusion Criteria:

1. Subject's BMI <18 or >30
2. Subject has poorly controlled or untreated hypertension.
3. Subject has severe ischemic heart disease.
4. Subject is an untreated or undertreated patient with hyperthyroidism.
5. Subject has used drugs that affect their central nervous system.
6. .Subject has mental illness.
7. .Subject has epilepsy.
8. .Subject has a history of chronic pain.
9. .Subject is pregnant or breast-feeding.