Functional endoscopic sinus surgery (FESS) is one of the effective modalities for the treatment of Functional endoscopic sinus surgery (FESS) is one of the effective ways to treat chronic sinusitis, which has the advantages of deep approach, light trauma and less pain. However, the operation area involves the nose, eyes and skull.

However, because the operation area involves the nose, eyes and skull, the surrounding tissue structure is complex and rich in blood vessels and nerves, and the use of epinephrine, tissue damage, nerve irritation and other problems during the operation are all related to the treatment of chronic rhinosinusitis.However, because the operation area involves the nose, eyes and skull, the surrounding tissue structure is complex and rich in blood vessels and nerves, and the use of epinephrine, intraoperative tissue damage, nerve stimulation, postoperative inflammation, oedema, bleeding, nasal tamponade can cause stress reactions and The use of adrenaline, intraoperative tissue damage, nerve stimulation, postoperative inflammation, oedema, bleeding, and nasal tamponade can all cause stress reactions and postoperative pain in patients, resulting in anxiety, depression, and sleep disorders, thus reducing the quality of early postoperative recovery and affecting This reduces the quality of early postoperative recovery and affects the rapid recovery of patients. As an NMDA receptor antagonist, esketamine has a strong analgesic effect, fast onset of action and rapid metabolism. As an NMDA receptor antagonist, esketamine has a strong analgesic effect, fast onset of action and fast metabolism, which can effectively alleviate postoperative pain, reduce the need for analgesic drugs, prolong the duration of analgesia, reduce the use of opioids and prevent pain hypersensitivity and preventing nociceptive allergy. In addition, esketamine has been proved to be effective in improving depression and anxiety, as well as sleep disorders. In addition, esketamine has been shown to be effective in improving depression and anxiety and in improving sleep disorders. Based on the action of NMDA receptor antagonists, magnesium sulphate reduces opioid consumption and decreases postoperative pain scores, without increasing opioid use.

Postoperative pain scores, without increasing the risk of opioid side effects, significantly enhancing perioperative analgesia and reducing the need for analgesia 24 hours after surgery. Magnesium sulphate can reduce opioid consumption and postoperative pain scores without increasing the risk of opioid side effects, significantly enhancing perioperative analgesia and reducing the need for analgesia 24 hours after surgery. At present, few studies and experiences have been reported on the use of esketamine and magnesium sulphate in ERAS in otorhinolaryngology, head and neck surgery. At present, there are few studies and experiences on the use of esketamine and magnesium sulfate in ERAS in otolaryngology, head and neck surgery. The aim of this study was to investigate the effects of intravenous infusion of esketamine or magnesium sulfate on postoperative pain and emotional state in patients undergoing nasal endoscopy. The aim of this study was to investigate the effects of intravenous infusion of esketamine or magnesium sulfate on postoperative pain, emotional state and quality of recovery in patients undergoing nasal endoscopy.

The aim of this study was to investigate the effects of intravenous infusion of esketamine or magnesium sulphate on postoperative pain and quality of recovery in patients undergoing nasal endoscopic surgery.Patients were randomised into group S: intravenous infusion of esketamine (0.25 mg/kg over 10 minutes before induction, then 0.25 mg/kg/h); group L intravenous infusion of magnesium sulphate (30 mg/kg over 10 minutes before induction, then 30 mg/kg/h). The control group was pumped with an equal volume of saline over the same time period. Patients were randomly allocated to the esketamine group, magnesium sulphate group and control group in a 1:1 ratio using a computer generated random sequence and the sealed envelope method. Patients, anaesthetists and researchers observing the results were unaware of the allocation of patients to groups.The patients were routinely fasted for 6 h and abstained from drinking for 2 h preoperatively.The patient was admitted to the room with an open peripheral vein and a continuous infusion of sodium lactate Ringer's solution; cardiac monitoring, pulse rate were routinely performed,oxygen saturation (SpO2) and ECG.A temperature-controlled blanket was used intraoperatively to maintain normothermia. In all three groups, intravenous midazolam 0.05 mg/kg, propofol 1.5 mg/kg, rocuronium bromide 0.6 mg/kg, and sufentanil 0.5 μg/kg were injected.The patients in all three groups were induced with intravenous midazolam 0.05 mg/kg, propofol 1.5 mg/kg, rocuronium bromide 0.6 mg/kg, and sufentanil 0.5 μg/kg for routine fast-channel induction. During anaesthesia maintenance, remifentanil 0.1-0.5 ug/kg/min, sevoflurane (1%-3%) and propofol 4-12 mg/kg were continuously infused in all three groups.Sevoflurane (1%-3%), and Propofol 4-12 mg/kg/h were continuously infused in all three groups. All three groups of patients were connected to a ventilator with 2.0 L/min of pure oxygen for respiratory control, and the parameters were set as follows: tidal volume of 6-8 ml/kg, inspiratory/expiratory ratio of 1:2, and PETCO2 control of 35-40 mmHg. The appropriate depth of anaesthesia was maintained.Maintain appropriate anaesthesia depth (entropy index RE/SE 40～60).At the appropriate depth of anaesthesia, vasoactive drugs (ephedrine, phenylephrine, nitroglycerin) can be administered to regulate blood pressure. Immediately after the procedure, the patient is transferred to the PACU and the endotracheal tube is removed when the patient regains consciousness and can breathe spontaneously. In the PACU, pain severity was measured at fixed intervals on a 10-point numerical rating scale (VAS, 0-10), and postoperative VAS scores >3 were given intravenously with ketorolac aminotriol injection 30 mg for remedial analgesia.

Inclusion Criteria:

• Age between 18 and 65 years
• American Society of Anesthesiologists (ASA) classification I-II
• Patients scheduled for FESS under general anaesthesia and with a procedure duration of not less than 30 minutes.

Exclusion Criteria:

• Patients with hypersensitivity to esketamine, magnesium sulphate and other anaesthetic drugs;
• Combined vital organ insufficiency;
• Pregnant and lactating women;
• Those with a history of substance abuse;
• Patients who are unable to understand the study or who are mentally ill;
• Uncontrolled diabetes mellitus, hypertension, hyperthyroidism;
• Failure to understand or cooperate with HADS, SAS, SDS questionnaires, or the Pain Assessment Scale (VAS);
• Those who do not sign the informed consent form.

The randomization sequence was generated by a computer and handed over in sealed opaque sequentially numbered envelopes. The envelope was opened by anaesthetist not involved in the study and drugs were dispensed as per the allocation card. The configured drugs were then handed over to experienced anaesthetists who were not aware of the subgroups