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 analyze the current status and influencing factors of occupational stress among medical staff during major public health emergencies. Methods A total of 491 medical staff in Guangzhou City was selected as the research subjects using a convenient sampling method. The Job Content Questionnaire and Effort-Reward Imbalance Questionnaire were used to evaluate the occupational stress level in the job demand-control (JDC) and effort-reward imbalance (ERI) models among the staff. Results Among the research subjects, the detection rates of occupational stress in JDC and ERI models were 50.1% and 52.5%, respectively. There was no significant difference in the detection rates of occupational stress between the two models (P>0.05). The result of multivariate logistic regression analysis showed that individuals with lower monthly income and longer weekly working hours had a higher risk of occupational stress in both JDC and ERI models (all P<0.05). Staff with night shift, daily sleep time less than six hours, and dissatisfaction with the protective measures provided by the hospital had higher risk of occupational stress than those with no night shift, daily sleep time at least six hours, and satisfaction with the protective measures provided by the work place in JDC and ERI models (all P<0.01). The risk of ERI model occupational stress of personnel who had been exposed to COVID-19 cases or suspected cases was higher than that in those who had not been exposed (P<0.05). Conclusion Medical staff experience a certain level of occupational stress, characterized by both JDC and ERI models, during major public health emergencies. The main influencing factors included personal monthly income, weekly working hours, night shift, sleep time, satisfaction with protective measures and occupational exposure.

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.

Aiming at the problem of timeliness of CBCT reconstruction, a CBCT fast short scan reconstruction method is proposed. At the same time, the image reconstruction process in which a new attenuation compensation algorithm is applied to improve image quality. When performing FDK three-dimensional reconstruction of a single-frame acquisition image, the Parker-weighted image is calculated in real time, and a new attenuation compensation algorithm is applied in the back projection process to complete the short scan Parker-weighted reconstruction. This method simulates the CBCT synchronous acquisition and reconstruction process by establishing collection and reconstruction threads. Under the premise of satisfying the reconstruction quality, the reconstruction can be completed within 1 to 2 seconds after the patient collection is completed, which achieves the purpose of real-time.
Algorithms ; Cone-Beam Computed Tomography ; Humans ; Image Processing, Computer-Assisted ; Spiral Cone-Beam Computed Tomography

In order to improve the speed and accuracy of cone beam CT image quality assurance, an automatic image quality assurance software based on feature extraction is designed and implemented. This paper introduces how the software can realize the positioning of Catphan500 phantoms and the selection of ROI in each module through Canny algorithm and Hough transform circle detection. For the different modules in the Catphan500 phantom, this paper describes the calculation methods of HU accuracy, spatial linearity, HU uniformity and spatial linearity in the software. Finally, the article verifies the feasibility of the software through experiments.
Algorithms ; Automation ; Cone-Beam Computed Tomography ; Phantoms, Imaging ; Quality Control ; Software

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 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.