Effects of Intravenous Lidocaine on ED50, ED95 and NTI Values of Propofol Induced Unconsciousness

The effect of intravenous lidocaine on ED50 and ED95 of propofol, which causes unconsciousness, is unclear. In addition, it is not clear whether the depth of anesthesia induced by propofol changes when lidocaine is used in combination. Therefore, the purpose of this study was to study the effects of intravenous lidocaine on ED50, ED95 and NTI values of propofol induced unconsciousness .

Intravenous lidocaine has many advantages in perioperative period, in addition to reducing the amount of opioids and propofol, thus reducing the incidence of adverse reactions caused by them, it also has the effect on organ protection, can shorten the length of hospital stay, and promote postoperative recovery. The effect of intravenous lidocaine on ED50 and ED95 of propofol, which causes unconsciousness, is unclear. In addition, it is not clear whether the depth of anesthesia induced by propofol changes when lidocaine is used in combination. Therefore, the purpose of this study was to study the effects of intravenous lidocaine on ED50, ED95 and NTI values of propofol induced unconsciousness .

The experimental group received 1.5 mg/kg lidocaine intravenously,after 90s, the corresponding dose of propofol was injected intravenously at 30mg/kg/h, and to observe Whether consciousness disappears or not，recording NTI values, heart rate, oxygen saturation, mean arterial pressure and drug side effects in the baseline state, 90s after lidocaine administration, 60s and 120s after propofol administration

The experimental group was injected with lidocaine 1.5mg/kg, and propofol was pumped intravenously at 90s after lidocaine injection.The dose of propofol was further set according to groups. The heart rate, mean arterial pressure, pulse oxygen saturation and NTI values of subjects were recorded in tne basic state,during the 90s after lidocaine administration, 60s after propofol administration and consciousness loss.The control group simply replaced lidocaine with equal volume normal saline

Inclusion Criteria: The informed consent is signed Aged 18 to 65 years old ASA is rated from I to II Body mass index ranged from 18.5 to 24.9 kg/m2 Exclusion Criteria: Unwilling to sign informed consent or refuse to participate in the study Patients with serious arrhythmia and organic heart disease before surgery Sedative and analgesic drugs were taken within 1 week before surgery Lidocaine allergy Patients with mental and neurological diseases Patients with difficult airway People with hearing impairment