Objective To evaluate the effect of neuromuscular block on the airway sealing pressure of laryngeal mask airway (LMA) i-gel in patients undergoing general anesthesia.Methods Sixty patients scheduled for elective surgery under general anesthesia with LMA i-gel were randomly allocated to one of three groups (n =20 each):control group (group C),rocuronium 0.3 mg/kg group (group R1) and rocuronium 0.6 mg/kg group (group R2).Anesthesia was induced with target-controlled infusion of propofol and remifentanil.The target plasma concentration of propofol was 3.5 μg/ml,and the target effect-site concentration of remifentanil was 3.0 ng/ml.When the patients lost consciousness and after the target plasma and effect-site concentrations were balanced,LMA i-gel was inserted to perform mechanical ventilation.After insertion of LMA i-gel,rocuronium 0.3 and 0.6 mg/kg were injected in R1 and R2 groups,respectively.The airway sealing pressure of LMA i-gel was detected immediately after insertion of LMA i-gel and at 1 min after administration of rocuronium.Results There was no significant difference in the airway sealing pressure of LMA i-gel between groups and within groups(P ＞ 0.05).Conclusion Neuromuscular block has no significant effect on the airway sealing pressure of LMA i-gel in patients undergoing general anesthesia.

Objective To evaluate the influencing factors for postoperative odynophagia in elderly patients undergoing intraoperative transesophageal echocardiography (TEE) examination for cardiac surgery.Methods A total of 96 patients with intraoperative TEE examination for cardiac surgery was divided into two groups:the elderly group (patients aged ≥65 years,n=60) and the young group (patients aged ＜ 65 years,n =36).Clinical data were retrospectively analyzed.Postoperative odynophagia was assessed by number rating scale (NRS) scores.Characteristics of postoperative odynophagia were compared between the two groups.Influencing factors for postoperative odynophagia were analyzed by multivariable logistic regression analysis.Results The incidence of postoperative odynophagia and the average NRS score were higher in the elderly group thanin the young group [88.3％ vs.66.7％,(2.6±1.7) vs.(1.4±0.9),P＜0.05 or 0.01].Multivariate logistic regression analysis showed that preoperative oral lidocaine plasmagel,oropharyngeal mucosal injury and duration of TEE insertion were independent influencing factors for postoperative odynophagia (all P＜0.01).Conclusions The incidence of postoperative odynophagia is higher and the degree of odynophagia is more serious in elderly patients undergoing intraoperative TEE examination for cardiac surgery.Postoperative odynophagia can be relieved by applying the preoperative oral lidocaine plasmagel,reducing oropharyngeal mucosal injury and shortening the duration of TEE insertion.

Objective To determine the relationship between neuronuscular block induced by cisatracurium for tracheal intubation during anesthesia induction and types of myasthenia gravis (MG).Methods Sixty-five patients of both sexes with MG,aged 20-75 yr,weighing 53-92 kg,with body height of 155-185 cm,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,undergoing elective videoassisted thoracoscopic thymectomy,were enrolled in the study.Among the 65 patients,there were 8 patients with ocular MG (type Ⅰ),19 patients with mild generalized MG (type]Ⅱ a),33 patients with subacute generalized MG (type Ⅱ b),2 patients with acute MG (type Ⅲ) and 3 patients with late severe MG (type Ⅳ).Neuromuscular monitoring was initiated when the patients lost consciousness after induction of anesthesia.Cisatracurium was administrated with the initial dose of 0.05 mg/kg,and if T1 depression was less than 95％ within 6 min,cisatracurium 0.015 mg/kg was intravenously injected until T1 depression was more than 95％.The patients were then tracheally intubated.The amount of cisatracurium consumed for intubation,onset time (from the beginning of cisatracurium injection to T1 depression ＞95％) and recovery time (recovery of T4/T1 to 25％ of control height) of neuromuscular block were recorded.T1 depression ＞ 95％ within 6 min after administration of 1-fold ED95 cistracuriun was defined as sensitivity to muscle relaxants.The requirement for cistracurium ＞ 1-fold ED95 when T1 depression ＞ 95％ was defined as insensitivity to muscle relaxants.The proportion of sensitivity/insensitivity was calculated.Results There was no significant difference in the amount of cisatracurium consumed for intubation and onset time and recovery time of neuromuscular block between patients with type Ⅰ and those with type Ⅱ a (P＞0.05).Compared with patients with type Ⅰ and type]Ⅱ a,the amount of cisatracurium consumed for intubation was significantly decreased,the proportion of sensitivity/insensitivity was increased,the onset time was shortened,and the recovery time was prolonged in patients with type Ⅱ b (P＜0.05).Conclusion With the severity of MG,the consumption of cisatracurium is gradually decreased when used for tracheal intubation during anesthesia induction,and the sensitivity is gradually increased in the patients with MG.

Objective To investigate the neuromuscular block effect of intravenous injection of cisatracurium in myasthenia gravis patients with different ages.Methods Fifteen geriatric patients defined as geriatric group(≥ 65 years old)with ASA Ⅰ-Ⅱ scheduled for video-assisted thoracoscopic (VATS)thymectomy with Ⅱ b MG and fifteen young-middle aged Ⅱ b MG patients defined as youngmiddle aged group (20-50 years) with paired sex,clinical symptoms,duration of symptoms,preoperative treatment regimen,anesthesia management and surgical time were included.Neuromuscular block was monitored with TOF Watch acceleration instrument.After induction of intravenous anesthesia,0.05mg/kg Cisatracurium was administrated intravenously,followed by increments of 0.015 mg/kg until T1/T0 was less than 5％ for each patient.A double-lumen bronchial tube was intubated when T1/T0 was less than5％.0.015 mg/kg cisatracurium was injected during the operation when T4/T1 was achieved to 25％.The dose of cisatracurium,the duration of blockade maintenance,duration of clinical action and neuromuscular block recovery index were obtained.Results There were no significant differences in tracheal doses of cisatracurium [(0.058 ± 0.013)mg/kg vs.(0.053±0.009)mg/kg]and the duration of blockade [(31.5±9.6)min vs.(40.0±19.8)min] between geriatric group and young-middle age group (P＞0.05).The duration of clinical action of cisatracurium [(21.6±6.7)min vs.(33.7±13.4)min]and the time to achieve a TOFr of 25％ were significantly shorter in geriatric MG group than those in young-middle aged MG group (P=0.045,0.037).The geriatric MG group were administrated more increments of ciastracurium than the young middle aged MG group during surgery (P=0.025).There was no significant difference in the time to achieve a TOFr of 70％ [(49.3±16.4)min vs.(57.4±34.7)min] and 90％ [(61.6± 19.2)min vs.(64.3±35.9)min] between geriatric MG group and young-middle aged MG group (P＞ 0.05).Conclusions The duration of clinical action of cisatracurium in geriatric MG patients was shorted than that in young-middle aged MG patients which was different with neuromuscular block effect in normal patients.It is suggested to do more studies to estimate the influence of age on cisatracurium and other muscle relaxants in MG patients.

Objective To investigate the variations of mtDNA from high and low metastatic mouse hepatocarcinoma cell sublines Hca-F and Hca-P, and the relationship between mutations of mtDNA and carcinogenesis. Methods The variations of D-loop, ND3 and tRNA Met+Glu+Ile gene fragments of mtDNA from Hca-F and Hca-P cells were analyzed by PCR-RFLP and sequencing techniques. Results No amplification fragment length polymorphism and restriction fragment length polymorphism were observed in tRNA Met+Glu+Ile , ND3 and D-loop of mtDNA from the 2 cell sublines. Sequence difference between these 2 cell sublines were found in mtDNA D-loop region by sequencing. Conclusions Genetic alteration of mtDNA non-coding region in tumors, which may reflect the environmental and genetic influences operative during tumor progression, can be linked to their tumorigenic phenotype.

Objective To study the 4 977 bp deletion of mitochondrial DNA in lung cancer, paraneoplastic tissue and normal lung tissue from non-lung cancer subjects and its significance in the development of cancer. Methods Lung cancer tissues and paraneoplastic tissues from 37 non-small lung cancer patients, and normal lung tissues from 20 patients without lung cancer were analyzed by long PCR technique. Results Mitochondrial DNA 4 977 bp deletion was detected in 54.1%(20/37) of lung cancer tissues, 59.5%(22/37) of paraneoplastic tissues and 30.0%(6/30) of normal lung tissues. The correlation between 4 977 bp deletion and age, smoking was present in our data. Conclusion Mitochondrial DNA 4 977 bp deletion, which may reflect the environmental and genetic influences during tumor progression, is not specific to lung cancer and unlikely to play an important role in carcinogenesis.

Objective To evaluate the effects of different anesthetic methods on postoperative acute pain in patients with myasthenia gravis undergoing video-assisted thoracoscopic thymectomy.Methods Fifty-four patients of both sexes,aged 18-64 yr,with body mass index of 20-28 kg/m2,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,scheduled for elective video-assisted thoracoscopic thymectomy,were allocated into 2 groups (n =27 each) using a random number table method:sevoflurane-based anesthesia group (group S) and propofol-based anesthesia group (group P).After routine anesthesia induction in two groups,anesthesia was maintained by inhaling sevoflurane and target-controlled infusion of remifentanil in group S and by target-controlled infusion of propofol and remifentanil in group P.Heart rate and mean arterial pressure were recorded before operation and at 5 and 10 min after extubation (T1.2).The intensity of pain at T2 and visual analog scale (VAS) score and consumption of morphine at 1,2,4,24 and 48 h after operation (T3-7) were recorded.The pressing times of analgesia pump,requirement for rescue analgesia and development of nausea and vomiting were recorded at T7.Results There were no significant differences in heart rate or mean arterial pressure at each time point between two groups (P＞0.05).Compared with group S,the intensity of pain was significantly alleviated at T2,and VAS scores and morphine consumption were decreased at T3,4 in group P (P＜0.05).There were no significant differences between group P and group S in VAS scores or consumption of morphine at T5-7,or pressing times of analgesia pump,requirement for rescue analgesia or incidence of nausea and vomiting at T7 (P＞0.05).Conclusion Propofol-based anesthesia provides better efficacy in alleviating postoperative acute pain in patients with myasthenia gravis undergoing video-assisted thoracoscopic thymectomy.

Transcrestal maxillary sinus floor elevation is an effective method to solve the problem of insufficient bone height in the posterior maxillary region.However,current methods,such as osteotome sinus floor elevation,cushioned grind-out technique,Smart Drill technique,etc.,require specialized surgical tool boxes.In this article,we introduce a new method of transcrestal maxillary sinus elevation that uses built-in reamers of various implant systems to scrap residu-al bone at the sinus floor and uses the implant to push the sinus membrane during implant placement.This technique is easy to operate and time saving and has a low rate of sinus membrane perforation.After a one-year follow-up observa-tion of 146 people and 175 implants,the endo-sinus bone gains were 5.00(4.70,5.30)mm and 2.10(1.40,2.70)mm in the group of 3 mm≤residual bone height(RBH)<5 mm and the group of 5 mm≤RBH<8 mm,respectively,which can meet the clinical requirements of implant stability.This technique is suitable in generalizing dental implantation.

Objective:To analyze the incidence of postoperative pulmonary complications and related factors in elderly patients after major abdominal surgery.Methods:Clinical data of elderly patients undergone major abdominal surgeries at Beijing Hospital were retrospectively analyzed.The incidence of postoperative pulmonary complications was studied, and related factors were analyzed using Logistic regression analysis.Results:A total of 96 cases were included.The incidence of postoperative pulmonary complications was 53.1%(51/96)in elderly patients after major abdominal surgery.Logistic regression analysis showed laparoscopy was a protective factor for postoperative pulmonary complications( OR=0.293, 95% CI: 0.100-0.865, P=0.026), while driving pressure > 18 cmH 2O(1 cmH 2O=0.098 kPa)( OR=3.300, 95% CI: 1.148-9.434, P=0.027)and intraoperative bleeding volume > 500 ml( OR=4.444, 95% CI: 1.091-18.180, P=0.037)were risk factors for postoperative pulmonary complications. Conclusions:Attention should be paid to the incidence of postoperative pulmonary complications in elderly patients after major abdominal surgery.Laparoscopy is a protective factor for postoperative pulmonary complications, while driving pressure more than 18 cmH 2O and intraoperative bleeding volume more than 500 ml can increase the risk of postoperative pulmonary complications.

Data of patients underwent thoracic surgeries were retrospectively collected in our center from November 2016 to January 2019.The last recorded tidal volume and driving pressure before two-lung ventilation were selected.Patents were classified into driving pressure increase group (>15 cmH 2O) and normal group.The baseline characteristics, parameters of pulmonary function, left one-lung ventilation and protective ventilation strategies were recorded.Logistic regression analysis was used to identify the risk factors for driving pressure increase, correlation analyses between predicted body weight and total lung capacity and between forced vital capacity and total lung capacity were performed.The Receiver Operating Characteristic (ROC) curve was used to analyze the accuracy of the ratio of tidal volume to corrected forced vital capacity in predicting driving pressure increase.Sixty-two patients were included in this study.Body mass index, left one-lung ventilation and the ratio of tidal volume to corrected forced vital capacity ratio were the risk factors for driving pressure increase ( P<0.05 or 0.01). Predicted body weight (correlation coefficient was 0.66, P<0.01) and forced vital capacity (correlation coefficient was 0.75, P<0.01)were both positively correlated with total lung capacity, but the two coefficients were statistically significant difference ( P<0.05). The area under the ROC curve of the ratio of tidal volume to corrected forced vital capacity in predicting driving pressure increase was 0.846 (95% CI 0.749-0.943) ( P<0.01), the diagnostic threshold was 0.312, the sensitivity and specificity of this threshold were 0.800 and 0.781 respectively, so the boundary of tidal volume during one-lung ventilation should be either forced vital capacity×0.149 for left one-long ventilation or forced vital capacity×0.163 for right one-lung ventilation.In conclusion, the ratio of tidal volume to corrected forced vital capacity has a higher predictive value for driving pressure increase during one-lung ventilation, and forced vital capacity can be used as a reference while calculating tidal volume.