Procedures
postoperative nausea and vomiting, NRS
GROUP B, STERILE, STERILE, CAVITY, INFILTRATED
After patients were admission, oxygen was administered and ECG, HR, NBP and SPOThe enrolled patients were randomized by random number method into three groups: Group M (5 μg/kg morphine intrathecal injection), Group B (5 μg/kg morphine combined with bupivacaine 3 mg intrathecal injection) and Group C (intrathecal sham injection). Patients were randomly allocated 1: 1: 1 with three treatment groups using a set of computer-generated random numbers kept in sealed envelopes by an investigator not involved in clinical care. Blocks were performed before induction of general anaesthesia, and patients were not informed of their group assignments. The three groups were intrathecal injection morphine, morphine and bupivacaine, or intrathecal sham injection. The anaesthetist conducting the anaesthetic was not blinded to treatment.Group M: Under standard monitoring, patients were placed in the left lateral position and the skin of the low back was disinfected with 0.45–0.55% povidone-iodine disinfectant centred on the L2-3 gap and sterile cavity wipes were laid. 1% lidocaine 2 ml was infiltrated locally and a type II lumbar puncture needle (5#) was used to perform an intrathecal puncture in the L2-3 space. The cerebrospinal fluid was drained freely and morphine hydrochloride 5 μg/kg was injected into the subarachnoid space within 15 s. Morphine hydrochloride configuration: dilute 1 mg morphine hydrochloride (1 mg/ml) with 0.9% sodium chloride to 10 ml (0.1 mg/ml) and inject into a 3 ml syringe after drawing at 5 μg/kg using a 1 ml syringe. Retract cerebrospinal fluid diluted to 3 ml for subarachnoid injection.Group B: The procedure for subarachnoid puncture was the same as that for M group. 5 μg/kg of morphine hydrochloride (morphine preparation was the same as that for M group) combined with 0.75% bupivacaine 0.4 ml (3 mg) was withdrawn and diluted to 3 ml of cerebrospinal fluid for subarachnoid injection.Group C: After the patient has cooperated in the position, the anaesthetist applies finger pressure to the skin to simulate intrathecal injection.The 10°Trendelenburg position was used in all three groups. The flat position was resumed 20 min after completion of the operation to achieve a high plane block. Sterile dressings were given to cover the lumbar back after completion of the puncture operation in all three groups. The upper boundary of the plane of anaesthesia was measured with an alcohol swab 10–15 min after administration.For all three groups, general anaesthesia was induced with 0.05 mg/kg midazolam, 0.4 μg/kg sufentanil and 1.5–2.0 mg/kg propofol. Cisatracurium 0.2 mg/kg was given to facilitate double-lumen bronchial tube intubation. Propofol administration was adjusted to target a Bispectral Index between 40 and 60. Cisatracurium was infused at 0.05 ~ 0.10 mg·kgPostoperative analgesia: All three groups received PCIA after awakening in the PACU with the same settings: sufentanil 2 μg/kg and azasetron 10 mg diluted to 100 ml with 0.9% NaCl. PCA dose, 2 ml, lockout interval 15 min. If the PCA device was fully used (NRS > 4 after three consecutive effective compressions), then aminotriol ketorolac 30 mg is administered intramuscularly for remedial analgesia. In case of postoperative nausea and vomiting, metoclopramide 10 mg is administered intramuscularly.