Backward-upward-rightward pressure(BURP)maneuver can improve glottic view and increase the success rate of intubation when direct laryngoscopy is used to solve difficult endotracheal intuba-tion,but some studies believe that it can worsen glottic view.With the wide application of video-laryngosco-py,the clinical value of BURP technique has again aroused controversy.This article reviews the definition,method,basic principle of BURP maneuver,effect of the BURP maneuver to improve glottic view during the using laryngoscopy,in order to provide reference for the solution of difficult erdotracheal intubation.

Rapid sequence induction and intubation(RSII)is a protective process in patients at high risk of aspiration/regurgitation in an emergency.The procedures of classical RSII include effective pre-oxygenation,administration of thiopental and succinylcholine,application of cricoid pressure,avoidance of positive-pressure ventilation before intubation,and intubation with a cuffed tracheal tube.Although RSII has evolved many times,its clinical benefits and risks remain undefined.In particular,some of the traditional concepts of RSII have been changed by the development of pre-oxygenation,visualization of intubation,application of positive-pressure ventilation,and other new techniques.This article reviews the latest progress of RSII research,aiming to provide a better reference for clinical practice.

Objective To investigate the risk factors for perioperative hypotension in severe patients after liver cancer surgery and its influence on prognosis. Methods A retrospective analysis was performed for the clinical data of 422 patients who underwent surgical treatment due to primary liver cancer or metastatic liver cancer and were then admitted to the intensive care unit (ICU) of Peking University People's Hospital from January 2014 to December 2019. The 107 patients requiring continuous intraoperative or postoperative pumping of vasoactive drugs (norepinephrine, dopamine, phenylephrine, and epinephrine) to maintain blood pressure were included in the hypotension group, and the 315 patients who did not require the pumping of vasoactive drugs to maintain blood pressure were included in the non-hypotension group. Related clinical data were collected from all patients, including sex, age, body mass index, history of liver surgery, comorbidities, underlying liver diseases, preoperative laboratory examinations, surgical data, and anesthesia, and the two groups were compared in terms of related prognostic indicators (in-hospital mortality, length of ICU stay, length of hospital stay, duration of mechanical ventilation, acute kidney injury, hypoxemia, pulmonary infection, and myocardial injury). The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups; the chi-square test was used for comparison of categorical data between two groups. The clinical indices with P < 0.1 were included in the binary logistic regression analysis to investigate the risk factors for hypotension. Results The overall mortality rate was 1.9% for the severe patients after liver cancer surgery, with a mortality rate of 3.7% in the hypotension group and 1.3% in the non-hypotension group. Compared with the non-hypotension group, the hypotension group had a significantly longer length of ICU stay ( Z =-6.440, P < 0.001), a significantly longer duration of mechanical ventilation ( Z =-6.082, P < 0.001), and a significantly higher proportion of patients with acute kidney injury, hypoxemia, and pulmonary infection after surgery ( χ 2 =25.661, 25.409, and 20.126, all P < 0.001). The clinical indices with P < 0.1 between the two groups (coronary heart disease, ascites, preoperative levels of albumin/platelets/fibrinogen, time of operation and hepatic portal occlusion, laparotomy, blood loss) were included in the binary logistic regression analysis, and the results showed that time of operation (odds ratio [ OR ]=1.004, 95% confidence interval [ CI ]: 1.002-1.006, P < 0.05) and blood loss ( OR =1.151, 95% CI : 1.009-1.313, P < 0.05) were independent risk factors for hypotension in patients undergoing liver cancer surgery, while preoperative albumin level ( OR =0.950, 95% CI : 0.907-0.995, P < 0.05) was a protective factor. Conclusion There is a relatively high incidence rate of hypotension among severe patients after liver cancer surgery, and a longer time of operation and greater blood loss are independent risk factors for hypotension, while a higher preoperative albumin level is a protective factor.

Background Hand-arm vibration disease is harmful to human body, but there are no effective diagnosis and treatment so far, and current occupational exposure limits underestimate the health damage caused by high-frequency vibration exposure. Objective To evaluate and compare the damage to workers' peripheral circulation and peripheral nerve caused by different frequencies of vibration operation. Methods Drilling workers (n=187) from a mining company in Shandong Province and golf club head grinding workers (n=228) from a sports equipment factory in Guangdong Province were selected as study subjects. Hand symptoms were investigated. SV106 vibration meter was used to measure the target operation-associated vibration frequency spectrum. The 8 h energy-equivalent frequency weighted acceleration, cumulative vibration exposure level (CVEL), and the working age related to causing white finger in 10% of an exposed group were calculated. Result The study subjects were all male. More grinding workers reported hand symptoms than the drilling workers, e.g. peripheral circulation injury (52.6% vs 19.3%), peripheral nerve injury (71.5% vs 23.0%), hand stiffness (64.0% vs 7.0%), and deformed fingers (69.7% vs 4.3%) (all P<0.001). The main vibration frequencies of grinding operation (500-800 Hz) were much higher than those of drilling operation (125~160 Hz). CVEL and working age of vibration exposure showed a linear rising relationship with the cumulative prevalence rate of peripheral circulation and peripheral never injury, the fitting lines all showed good fitting effects (R²=0.812-0.988), and the slope of the fitting line of the grinding workers was larger than that of the drilling workers. The working age of vibration exposure associated with 10% cumulative prevalence of white finger was shorter in the grinding workers than in the drilling workers (6.81 years vs 10.27 years). According to the ISO prediction formula, the working age of vibration exposure was associated with 10% white finger prevalence shorter in the drilling workers than in the grinding workers (3.12 years vs 8.23 years). Conclusion Both the vibration exposure level and the prevalence of hand symptoms are high in two groups of workers with different vibration frequencies, and vibration exposure at a higher frequency tends to have severer damage to workers' hands.

OBJECTIVE: To analyze the characteristic change of fingertip vibrotactile perception threshold(VPT) at two different frequencies among mine drilling workers. METHODS: A total of 48 mine drilling workers exposed to hand-transmitted vibration for at least 1.0 year were selected from mines in Hubei Province as the vibration exposure group by using the random number table method, and workers without hand-transmitted vibration exposure were selected as the control group. An HVLab vibrotactile perception meter was used to measure the fingertip VPT at 31.5 and 125.0 Hz in workers of these two groups. RESULTS: None of the workers in these two groups showed any clinical symptoms associated with occupational hand-arm vibration diseases. At 31.5 and 125.0 Hz, the fingertip VPT in the vibration exposure group was higher than that in the control group(P<0.01), the fingertip VPT of the little fingers was higher than that of the index fingers(P<0.01). At 125.0 Hz, the fingertip VPT of the fingers in dominant hands was higher than that in non-dominant hands in workers of the vibration exposure group(P<0.01). CONCLUSION: The mine drilling workers with hand-transmitted vibration exposure had higher fingertip VPT. There were differences of VPT in fingers and dominant hands.

Objective To investigate the effect of carbon dioxide pneumoperitoneum on the ox-ygen carrying capacity and electrolyte levels in the salvaged autologous blood undergoing laparoscopic surgery.To evaluate the clinical application value and to provide guidance for the salvage and transfu-sion of autologous blood in laparoscopic surgery.Methods Twenty cases who underwent laparoscopic surgery (group CP,laparoscopic hepatic hemangioma surgery)and twenty cases who underwent open surgery(group NCP,spinal surgery),including eighteen males and twenty-two females,aged 27-79, BMI 1.64-24.46 kg/m2,ASA Ⅰ-Ⅱ,were selected from Peking University People's Hospital from May 2016 to August 2017.Cases in both groups underwent general anesthesia.NBP,IBP,ECG, HR,SpO2,PETCO2,CVP,BIS and T were monitored and autologous blood salvage and transfusion were used during the operation.Arterial blood samples were collected from patients 10 min before and after autologous blood transfusion,salvaged blood samples were collected 1 min before and after fil-tration.Blood gas analysis,including the level of pH,PCO2,PO2,SO2,Hct,Hb,Lac and the con-centrations of Na+,K+,Ca2+,Cl-,Mg2+,were performed on all blood samples.Recording opera-tion time and blood in vitro time,blood loss volume intraoperative,total blood volume of salvage and transfusion.Results In group CP,pH,PO2and SO2of autologous blood 1 min before and after fil-tration were significantly lower than those of arterial blood 10 min before and after autologous blood transfusion (P<0.05).In group NCP,pH of autologous blood 1 min before and after filtration was significantly higher than that of arterial blood 10 min before and after autologous blood transfusion, while PCO2and PO2were significantly lower than the latter(P<0.05).PH,PO2and SO2of autolo-gous blood in group CP were significantly lower while PCO2was significantly higher than group NCP (P<0.05).PH of arterial blood 10 min after autologous blood transfusion was significantly lower while PCO2was significantly higher than group NCP (P<0.05).In group CP,the concentration of Na+and Cl- in autologous blood 1 min after filtration were significantly higher than those before fil-tration and the arterial blood 10 min before and after autologous blood transfusion.The concentration of K+,Ca2+and Mg2+in autologous blood 1 min after filtration were significantly lower than the lat-ter three blood samples (P<0.05).In group NCP,the concentrations of Na+and Cl- in autologous blood 1 min after filtration were significantly higher than those in arterial blood 10 min before and af-ter autologous blood transfusion.The concentrations of K+,Ca2+and Mg2+were significantly lower than those in the latter two blood samples (P<0.05).There were no significant differences in elec-trolyte concentration of all blood samples between two groups.Conclusion The salvaged blood in lap-aroscopic surgery is superacid and carrying less oxygen.After transfusion,may change patients'acid-base balance and increase the risk of acidosis.Its clinical application value need more further explora-tions.

Objective To investigate the effect of neuropeptide Y (NPY) on the osteoblastic differentiation of murine MC3T3-E1 cells and its mechanism related to the Wnt signaling pathway.Methods The murine MC3T3-E1 cells were divided into 4 groups according to the stimulators added:phosphate buffered saline (PBS) (control) and different concentrations of NPY (10-8 mol/L,10-10 mol/L and 10-12 mol/L).The cellular proliferation was detected with MTT assay after 1,3,5,7 and 9 days.The cells were identified with cell immunochemistry and Western Blot to find out the most effective concentration of NPY at different time points under osteoblastic condition.The cells were then divided into 4 groups:PBS,NPY,NPY + NPY receptor antagonist,and NPY + DKK1.Western blot was used to determine the expression of β3-catenin and p-GSK-3β in each group.Nuclear signaling activity of β3-catenin was observed using immunofluorescence staining.Results NPY significantly improved the proliferation of MC3T3-E1 cells at 7 and 9 days (P ＜0.05).NPY (10s mol/L and 10-10 mol/L) groups and NPY (10-10 mol/L and 10-12 mol/L) groups significantly improved the ALP activity at 4 and 14 days respectively (P ＜ 0.05).At 4 days,the expression of ALP protein was significantly decreased in the NPY + DKK1 group and the NPY + NPY receptor antagonist group compared with that in the NPY group (P ＜ 0.05).Although the expression levels of [β-catenin and p-GSK-3β protein were uninfluenced in either case,NPY significantly stimulated the nuclear signaling activity of β3-catenin.Conclusions NPY may significantly increase the expression of ALP protein in MC3T3-E1 ceils during osteoblastic differentiation.This effect might be mediated through the canonical Wnt signaling pathway.

Objective To analyze the clinical features,diagnosis and treatment of adult Moyamoya disease in countryside of the southeast of Hubei province.Methods Sixty-eight adult patients with Moyamoya disease,selected in countryside of the southeast of Hubei Province from May 2010 to May 2015,were enrolled.The clinical data,including age,gender,address (surrounding of residence),living habit (special hobby),health of family members,past medical history,symptom,confirmation related factors,treatment methods and prognoses,were retrospectively analyzed.Results These patients had high and low incidences in distribution.The ratio of male to female was 1.09:1.The peak age of onset was 35 to 44 years.There were 42 bleeding patients,16 ischemia patients,and 7 patients with atypical symptom,and 3 patients were asymptomatic.Thirty-eight patients (55.9％) had early diagnosis and 30 (44.1％) had late conformed diagnosis;patients with early diagnosis had significantly higher percentages of first diagnosis in the tertiary hospitals,hemorrhagic apoplexy as first onset,high education level and economic level than patients with late conformed diagnosis (P＜0.05).Ten patients died.Eight patients received vascular reconstruction,accounting for 11.8％ (8/58).Conclusions The distributions of adult moyamoya disease are regional cluster.The main age of onset is at the life prime.The initial symptom is hemorrhagic stroke.The time for diagnosis was short in the tertiary hospitals.The ratio of patients receiving vascular reconstruction is low.

Objective To determine the minimum alveolar concentration for endotracheal intu-bation (MACEI )of sevoflurane for curbing the responses to endotracheal intubation in 50% premature infants less than 37 weeks of corrected age.Methods Twenty-seven ASA Ⅰ or Ⅱ premature infants less than 37 weeks of corrected age were enrolled in this study.At first,the anesthesia induction was started by inhaling 6% sevoflurane.After the patient lost consciousness,the end tidal sevoflurane concentration (CET Sev)was adjusted to the target concentration and maintained stable for 1 5 min.En-dotracheal tube was then intubated.The up-and-down sequential method was used to calculate the MAC.The initial CET Sev was 3.0% and it was increased or decreased by 0.2% in the next patient ac-cording to the endotracheal intubation response.If the intubation response was positive,the CET Sev was increased;if the intubation response was negative,the CET Sev was decreased.The midpoint from negative response to positive response was set as a balance point and the mean value of the concentra-tions of sevoflurane at all the balance points were calculated as MACEI .Results The end tidal sevoflurane concentration for blunting the responses to endotracheal intubation in 50% premature in-fants was 2.55%±0.20%,and the MAC9 5 was 2.81% (95% confidence interval 2.67%-3.58%). Conclusion The MACEI of sevoflurane for curbing the responses to endotracheal intubation in 50%premature infants less than 37 weeks of corrected age is 2.55%,which is lower than that in the full-term children.

Objective To evaluate the intraoperative opioid-sparing effect of different frequency transcutaneous electrical acupoint stimulation (TEAS) in the patients undergoing video-assisted thoracoscopic pneumonectomy.Methods Eighty patients,aged 40-64 yr,weighing 50-90 kg,of ASA physical status Ⅰ-Ⅲ,scheduled for elective thoracoscopic pneumonectomy under general anesthesia,were randomly divided into 4 groups (n =20 each) using a random number table:control group (group Con),stimulation on Lieque (LU7)-Quchi (LI11)-Neiguan (PC6)-Hegu (LI4) at 2/100 Hz group (group 2/100 Hz),stimulation on LU7-LI11-PC6-LI4 at 2 Hz group (group 2 Hz),and stimulation on LU7-LI1 1-PC6-LI4 at 100 Hz group (group 100 Hz).The patients in group Con had the electrodes applied,but received no stimulation.In 2/100 Hz,2 Hz and 100 Hz groups,the patients received 2/100,2 and 100 Hz TEAS on LU7-LI11-PC6-LI4 acupoints ipsilateral to the surgery site,respectively,starting from 30 min before induction of anesthesia until the end of surgery,and the intensity was the maximum current that could be tolerated.Anesthesia was induced with iv midazolam,propofol,sufentanil and cisatracurim,and maintained with target-controlled infusion of remifentanil and propofol,continuous infusion of cisatracurim,and iv boluses of sufentanil when necessary.The target plasma concentration of propofol was adjusted to maintain BIS value at 40-60 during operation.The initial target effect-site concentration of remifentanil was 1 ng/ml,and adjusted to 4 ng/ml at skin incision.The concentration of remifentanil and consumption of sufentanil were adjusted to maintain Analgesia Nociception Index (ANI) at 50-70.When the concentration of remifentanil was increased to 4 ng/ml,ANI was still less than 50,and then 0.1 μg/kg sufentanil was given.The duration of operation and intraoperative consumption of remifentanil and sufentanil (the consumption of sufentanil was converted to the consumption of remifentanil producing the equivalent effect by 1:10) were recorded.Results The intraoperative consumption of remifentanil was significantly reduced in 2/100 Hz group as compared with Con,2 Hz and 100 Hz groups.There was no significant difference in the intraoperative consumption of remifentanil between Con group,2 Hz group and 100 Hz group.Conclusion The use of 2/100 Hz but not 2 and 100 Hz TEAS on LU7-LI11-PC6-LI4 significantly reduces intraoperative opioid consumption in the patients undergoing video-assisted thoracoscopic pneumonectomy.