Observation index
poisoning, nausea, hoarseness, vomiting, skin pain, prick pain, dyspnoea, nerve block
SECONDARY
The primary outcomes including block operation time (from the time when the ultrasonic probe contacts the neck skin to the time when the local anaesthetic injection is completed) in minutes, onset time of anaesthesia (after the injection is completed, the acupuncture method is used to test the reduction of skin pain within the scope of the surgical incision every minute, and the onset time of anaesthesia is from the time when the injection is completed to the time when the prick pain disappears) in minutes, the nerve block effect as a percentage, and the time of effective nerve block analgesia (the time of starting analgesia after the operation-the time of starting nerve block operation) in hours were recorded for both groups. The secondary outcomes including the number of patients requiring relief analgesia within 24 h were recorded, and the incidences occurrence of dyspnoea, hoarseness, local anaesthetic poisoning, nausea and vomiting in the two groups were recorded. Additionally, HR, SBP and DBP at the 5 min (T1)after entering the room, at the time of anaesthesia induction (T2), at 5 min after skin incision (T3) and at the time of leaving the operating room (T4) were recorded for the two groups.