Autism Spectrum Disorder (ASD) is a group of serious neurodevelopmental disorders. Autistic children appear with significant frequency for medical services, lots of which requiring procedural sedation or anaesthesia. Autistic children have often been described as difficult to sedate or anesthetize due to a variety of ASD symptoms. It is a challenging task to provide safe and effective sedation during the procedure of colonic TET for FMT in autism children. The investigators intend to explore an optimum anesthetic regimen for autism children undergoing endoscopic procedures.

Autistic children appear with significant frequency for medical services, lots of which requiring procedural sedation or anaesthesia. The participants have often been described as difficult to sedate or anesthetize due to a variety of ASD symptoms. It is a challenging task to provide safe and effective sedation during the procedure of colonic TET for FMT in autism children. The primary objective was to compare the clinical efficacy and safety of propofol-esketamine (PE) with propofol-sufentanil (PS) for deep sedation in the procedure of colonic TET in ASD children. A secondary objective was to compare adverse events (AEs) and recovery in those children during/after either PE or PS sedation.

Inclusion Criteria:

• (1) aged 2-12 years;
• (2) diagnosed with ASD by pediatric psychiatrists in accordance with the criteria in the Fifth Edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-V);
• (3) evaluated as American Society of Anesthesiologists (ASA) physical status I-II;
• (4) scheduled for colonic TET procedure.

Exclusion Criteria:

• (1) oral sedation (premedication) before intravenous catheter placement;
• (2) any contraindication to study medications;
• (3) other circumstances in which the investigator determined that a patient was not suitable for participation in the clinical trial.