The purpose of this study is to investigate the effect of Oxycodone Hydrochloride on catheter-related bladder discomfort in patients undergoing transurethral resection of bladder tumor after general anesthesia.

Catheter-related bladder discomfort(CRBD) is a frequent complication after indwelling catheter under general anesthesia. The incidence of CRBD in patients undergoing Transurethral resection is as high as 66.7-91.2%.CRBD may lead some poor prognosis including postoperative restlessness, bleeding, and circulatory instability.therefore，how to reduce the incidence of CRBD is one of the urgent problems to be solved in clinic.

Oxycodone Hydrochloride is a strong opioid receptor agonist used in clinic at present. It has certain advantages in the regulation of visceral pain and can produce analgesic effect without causing restlessness, gastrointestinal motility inhibition and respiratory inhibition through stimulating the μ and κ opioid receptor simultaneously. However, the effect of Oxycodone Hydrochloride on catheter-related bladder discomfort in patients undergoing transurethral resection of bladder tumor after general anesthesia is still unknown. The purpose of this study is to explore whether Oxycodone Hydrochloride via intravenous injection could reduce the incidence of CRBD in patients undergoing transurethral resection of bladder tumor after general anesthesia and could not increase other complications during the recovery period of general anesthesiathe.

Inclusion Criteria:

• More than 18 years old;
• ASA I - III;
• Plan to perform transurethral resection of bladder tumor under general anesthesia; (
• Agree to participate in this study and sign the informed consent form.

Exclusion Criteria:

• Refuse to participate in this study;
• Emergency surgery;
• Catheter was indwelling before operation;
• Taking opioids for a long time before operation;
• Previous history of schizophrenia, epilepsy, Parkinson's disease or myasthenia gravis;
• Unable to communicate due to coma, severe dementia or language disorder before operation;
• Critical condition (ASA grade ≥ IV before operation); Severe renal function damage (requiring renal replacement therapy); Severe liver function damage (child Pugh grade C); Acute stage of chronic obstructive pulmonary disease, severe asthma, severe pulmonary heart disease;
• History of opioid allergy.