Objective There is limited research on the combined use of multiple drugs in the prevention and treatment of radiation-induced oral mucositis (RTOM). This study aims to investigate the synergistic effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF), Kangfuxin Liquid, and vitamin B₁₂ via mouthwash on RTOM, and provide a novel approach for the prevention and treatment of acute RTOM. Methods A total of 82 patients with head and neck cancer who underwent radical radiotherapy were randomly divided into four groups: a control group (vitamin B₁₂, 20 cases), observation group 1 (rhG-CSF + vitamin B₁₂, 20 cases), observation group 2 (Kangfuxin Liquid + vitamin B₁₂, 21 cases), and observation group 3 (rhG-CSF + Kangfuxin Liquid + vitamin B₁₂, 21 cases). After 4 weeks of therapy, the therapeutic effects of the four groups were compared. Results Compared to the control group, there was no statistically significant difference in the incidence of RTOM. However, the incidence of severe RTOM was significantly reduced in the observation groups, following the order of observation group 1 (20.00%) > observation group 2 (14.28%) > observation group 3 (9.52%). The initiation period of RTOM in observation group 3 was 24 days, exhibiting a considerable delay in comparison to the control group (16 days), observation group 1 (18 days), and observation group 2 (22 days). The levels of pain experienced by the groups receiving combined treatments were significantly reduced compared to the control group. Observation group 3 exhibited the most effective pain reduction. Conclusion The combined administration of rhG-CSF, Kangfuxin Liquid, and vitamin B₁₂ can prevent radiation-induced oral mucosal injury and promote mucosal healing. This regimen represents an effective strategy for the prevention and treatment of acute RTOM.

Objective:To develop a grading system for necrosis of pedicled flaps in reconstruction of foot and ankle, and to verify its effectiveness and repeatability.Methods:A retrospective observational study was conducted. A total of 40 necroses of foot and ankle pedicled flaps were selected by 2 senior surgeons based on the flap surgery performed by the same surgical group in Department of Orthopaedic Surgery, the 920 Hospital of Joint Logistic Support Force of PLA from January 2010 to January 2022. A grading system for pedicled flap necrosis was proposed by a working group and the 40 necrotic flaps were graded. The coincidence rate was calculated to evaluate the effectiveness of the grading system through correlation studies between grading and clinical treatment. One photo of a typical postoperative necrotic flap was collected from each of the 40 flaps. Then 5 extramural surgeons were asked to grade the necroses shown on the photos according to the proposed grading system. Moreover, weighted Kappa analysis was performed on the results of proposed grading system and also on the standard grading currently in use, to evaluate the repeatability of the proposed grading system. Evaluated data were expressed by Mean±SD, and the coincidence rate was expressed by percentage. The reproducibility was studied by weighted Kappa analysis.Results:Of the 40 necrotic flaps, 7 flaps were classified in Grade I, 16 in Grade Ⅱ, 12 in Grade Ⅲ and 5 in Grade IV. In comparison with the actual treatment methods, the overall coincidence rate of the grading system was 92.5%. It indicated that the proposed grading system could effectively guide the selection of a treatment procedure. The average weighted Kappa coefficient of surgeons was at 0.628 with a 95% confidence interval (95%CI) between 0.460-0.796, which was strongly consistent with the standard of the grading system currently in use.Conclusion:The grading system for necrosis of pedicled flap in reconstruction of foot and ankle proposed in this study is simple and clear. It is able to effectively guide the treatment of flap necrosis. The preliminary validation shows that the classification system has good repeatability.

Objective:To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China.Methods:Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 μg/g·creatinine, middle:0.77-1.69 μg/g·creatinine, high:≥1.69 μg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model.Results:The mean age of subjects was (83.34±11.14) years old. The median (Q1, Q3) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) μg/g·creatinine, and the BMI was (22.70±3.82) kg/m 2. The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 μg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m 2, -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI ( Pnonlinear<0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference ( Plinear<0.001), hip circumference ( Plinear<0.001), and calf circumference ( Plinear<0.001). Conclusion:Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

Objective:To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China.Methods:Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 μg/g·creatinine, middle:0.77-1.69 μg/g·creatinine, high:≥1.69 μg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model.Results:The mean age of subjects was (83.34±11.14) years old. The median (Q1, Q3) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) μg/g·creatinine, and the BMI was (22.70±3.82) kg/m 2. The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 μg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m 2, -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI ( Pnonlinear<0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference ( Plinear<0.001), hip circumference ( Plinear<0.001), and calf circumference ( Plinear<0.001). Conclusion:Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

In view of the problems existing in current medical laboratory safety training, such as overly broad goals, a lack of diverse instructional methodologies, a disconnection between the content and the actual needs of students, and a "one-size-fits-all" assessment method, the outcome-based education (OBE) was applied to laboratory safety training. Reform and practice were carried out on four aspects: training objectives, methods, content, and assessment. The training program was constructed with the objectives of addressing the safety competency requirements for students entering the laboratory and enhancing their safety skills. The training method highlighted the dominant role of students, shifted from a unidimensional to a multidimensional approach, and increased student engagement. The training content was continuously updated and refined to align closely with the specific safety requirements of students conducting experiments. The whole process assessment method of formative evaluation was employed. The training effects were evaluated from course scores, competition performance, and questionnaire for satisfaction. The results indicate that, compared with traditional training methods, the OBE was more effective in focusing on training objectives and fostering student interest of learning. Although there was no significant difference in scores on foundational knowledge examinations, the OBE significantly enhanced student participation and strengthened their sense of belonging. The questionnaire survey showed that 94.22% (163/173) of the participants provided positive feedback regarding the OBE. Among these respondents, 68.21% (118/173) thought that the interactive teaching of case studies was more acceptable and 98.48% (65/66) praised the practical training, believing that it was more effective than traditional training to improve safety skills. Thus, the OBE can optimize safety education and training, improve students' safety competencies in multiple dimensions, and lay a solid foundation for subsequent laboratory learning and work.

Objective:To investigate the epidemiological characteristics, diagnosis, treat-ment and prognosis of gallbladder cancer in China from 2010 to 2017.Methods:The single disease retrospective registration cohort study was conducted. Based on the concept of the real world study, the clinicopathological data, from multicenter retrospective clinical data database of gallbladder cancer of Chinese Research Group of Gallbladder Cancer (CRGGC), of 6 159 patients with gallbladder cancer who were admitted to 42 hospitals from January 2010 to December 2017 were collected. Observation indicators: (1) case resources; (2) age and sex distribution; (3) diagnosis; (4) surgical treatment and prognosis; (5) multimodality therapy and prognosis. The follow-up data of the 42 hospitals were collected and analyzed by the CRGGC. The main outcome indicator was the overall survival time from date of operation for surgical patients or date of diagnosis for non-surgical patients to the end of outcome event or the last follow-up. Measurement data with normal distribu-tion were represented as Mean±SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M( Q1, Q3) or M(range), and com-parison between groups was conducted using the U test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Univariate analysis was performed using the Logistic forced regression model, and variables with P<0.1 in the univariate analysis were included for multivariate analysis. Multivariate analysis was performed using the Logistic stepwise regression model. The life table method was used to calculate survival rates and the Kaplan-Meier method was used to draw survival curves. Log-rank test was used for survival analysis. Results:(1) Case resources: of the 42 hospitals, there were 35 class A of tertiary hospitals and 7 class B of tertiary hospitals, 16 hospitals with high admission of gallbladder cancer and 26 hospitals with low admission of gallbladder cancer, respectively. Geographical distribution of the 42 hospitals: there were 9 hospitals in central China, 5 hospitals in northeast China, 22 hospitals in eastern China and 6 hospitals in western China. Geographical distribution of the 6 159 patients: there were 2 154 cases(34.973%) from central China, 705 cases(11.447%) from northeast China, 1 969 cases(31.969%) from eastern China and 1 331 cases(21.611%) from western China. The total average number of cases undergoing diagnosis and treatment in hospitals of the 6 159 patients was 18.3±4.5 per year, in which the average number of cases undergoing diagnosis and treatment in hospitals of 4 974 patients(80.760%) from hospitals with high admission of gallbladder cancer was 38.8±8.9 per year and the average number of cases undergoing diagnosis and treatment in hospitals of 1 185 patients(19.240%) from hospitals with low admission of gallbladder cancer was 5.7±1.9 per year. (2) Age and sex distribution: the age of 6 159 patients diagnosed as gallbladder cancer was 64(56,71) years, in which the age of 2 247 male patients(36.483%) diagnosed as gallbladder cancer was 64(58,71)years and the age of 3 912 female patients(63.517%) diagnosed as gallbladder cancer was 63(55,71)years. The sex ratio of female to male was 1.74:1. Of 6 159 patients, 3 886 cases(63.095%) were diagnosed as gallbladder cancer at 56 to 75 years old. There was a significant difference on age at diagnosis between male and female patients ( Z=-3.99, P<0.001). (3) Diagnosis: of 6 159 patients, 2 503 cases(40.640%) were initially diagnosed as gallbladder cancer and 3 656 cases(59.360%) were initially diagnosed as non-gallbladder cancer. There were 2 110 patients(34.259%) not undergoing surgical treatment, of which 200 cases(9.479%) were initially diagnosed as gallbladder cancer and 1 910 cases(90.521%) were initially diagnosed as non-gallbladder cancer. There were 4 049 patients(65.741%) undergoing surgical treatment, of which 2 303 cases(56.878%) were initially diagnosed as gallbladder cancer and 1 746 cases(43.122%) were initial diagnosed as non-gallbladder cancer. Of the 1 746 patients who were initially diagnosed as non-gallbladder cancer, there were 774 cases(19.116%) diagnosed as gallbladder cancer during operation and 972 cases(24.006%) diagnosed as gallbladder cancer after operation. Of 6 159 patients, there were 2 521 cases(40.932%), 2 335 cases(37.912%) and 1 114 cases(18.087%) undergoing ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) examination before initial diagnosis, respec-tively, and there were 3 259 cases(52.914%), 3 172 cases(51.502%) and 4 016 cases(65.205%) undergoing serum carcinoembryonic antigen, CA19-9 or CA125 examination before initially diagnosis, respectively. One patient may underwent multiple examinations. Results of univariate analysis showed that geographical distribution of hospitals (eastern China or western China), age ≥72 years, gallbladder cancer annual admission of hospitals, whether undergoing ultrasound, CT, MRI, serum carcinoembryonic antigen, CA19-9 or CA125 examination before initially diagnosis were related factors influencing initial diagnosis of gallbladder cancer patients ( odds ratio=1.45, 1.98, 0.69, 0.68, 2.43, 0.41, 1.63, 0.41, 0.39, 0.42, 95% confidence interval as 1.21-1.74, 1.64-2.40, 0.59-0.80, 0.60-0.78, 2.19-2.70, 0.37-0.45, 1.43-1.86, 0.37-0.45, 0.35-0.43, 0.38-0.47, P<0.05). Results of multivariate analysis showed that geographical distribution of hospitals (eastern China or western China), sex, age ≥72 years, gallbladder cancer annual admission of hospitals and cases undergoing ultrasound, CT, serum CA19-9 examination before initially diagnosis were indepen-dent influencing factors influencing initial diagnosis of gallbladder cancer patients ( odds ratio=1.36, 1.42, 0.89, 0.67, 1.85, 1.56, 1.57, 0.39, 95% confidence interval as 1.13-1.64, 1.16-1.73, 0.79-0.99, 0.57-0.78, 1.60-2.14, 1.38-1.77, 1.38-1.79, 0.35-0.43, P<0.05). (4) Surgical treatment and prognosis. Of the 4 049 patients undergoing surgical treatment, there were 2 447 cases(60.435%) with complete pathological staging data and follow-up data. Cases with pathological staging as stage 0, stage Ⅰ, stage Ⅱ, stage Ⅲa, stage Ⅲb, stage Ⅳa and stage Ⅳb were 85(3.474%), 201(8.214%), 71(2.902%), 890(36.371%), 382(15.611%), 33(1.348%) and 785(32.080%), respectively. The median follow-up time and median postoperative overall survival time of the 2 447 cases were 55.75 months (95% confidence interval as 52.78-58.35) and 23.46 months (95% confidence interval as 21.23-25.71), respectively. There was a significant difference in the overall survival between cases with pathological staging as stage 0, stage Ⅰ, stage Ⅱ, stage Ⅲa, stage Ⅲb, stage Ⅳa and stage Ⅳb ( χ2=512.47, P<0.001). Of the 4 049 patients undergoing surgical treatment, there were 2 988 cases(73.796%) with resectable tumor, 177 cases(4.371%) with unresectable tumor and 884 cases(21.833%) with tumor unassessable for resectabi-lity. Of the 2 988 cases with resectable tumor, there were 2 036 cases(68.139%) undergoing radical resection, 504 cases(16.867%) undergoing non-radical resection and 448 cases(14.994%) with operation unassessable for curative effect. Of the 2 447 cases with complete pathological staging data and follow-up data who underwent surgical treatment, there were 53 cases(2.166%) with unresectable tumor, 300 cases(12.260%) with resectable tumor and receiving non-radical resection, 1 441 cases(58.888%) with resectable tumor and receiving radical resection, 653 cases(26.686%) with resectable tumor and receiving operation unassessable for curative effect. There were 733 cases not undergoing surgical treatment with complete pathological staging data and follow-up data. There was a significant difference in the overall survival between cases not undergoing surgical treatment, cases undergoing surgical treatment for unresectable tumor, cases undergoing non-radical resection for resectable tumor and cases undergoing radical resection for resectable tumor ( χ2=121.04, P<0.001). (5) Multimodality therapy and prognosis: of 6 159 patients, there were 541 cases(8.784%) under-going postoperative adjuvant chemotherapy and advanced chemotherapy, 76 cases(1.234%) under-going radiotherapy. There were 1 170 advanced gallbladder cancer (pathological staging ≥stage Ⅲa) patients undergoing radical resection, including 126 cases(10.769%) with post-operative adjuvant chemotherapy and 1 044 cases(89.231%) without postoperative adjuvant chemo-therapy. There was no significant difference in the overall survival between cases with post-operative adjuvant chemotherapy and cases without postoperative adjuvant chemotherapy ( χ2=0.23, P=0.629). There were 658 patients with pathological staging as stage Ⅲa who underwent radical resection, including 66 cases(10.030%) with postoperative adjuvant chemotherapy and 592 cases(89.970%) without postoperative adjuvant chemotherapy. There was no significant difference in the overall survival between cases with postoperative adjuvant chemotherapy and cases without postoperative adjuvant chemotherapy ( χ2=0.05, P=0.817). There were 512 patients with pathological staging ≥stage Ⅲb who underwent radical resection, including 60 cases(11.719%) with postoperative adjuvant chemotherapy and 452 cases(88.281%) without postoperative adjuvant chemotherapy. There was no significant difference in the overall survival between cases with postoperative adjuvant chemo-therapy and cases without post-operative adjuvant chemo-therapy ( χ2=1.50, P=0.220). Conclusions:There are more women than men with gallbladder cancer in China and more than half of patients are diagnosed at the age of 56 to 75 years. Cases undergoing ultrasound, CT, serum CA19-9 examination before initial diagnosis are independent influencing factors influencing initial diagnosis of gallbladder cancer patients. Preoperative resectability evaluation can improve the therapy strategy and patient prognosis. Adjuvant chemotherapy for gallbladder cancer is not standardized and in low proportion in China.

Objective:To introduce the concept and procedure of CTA guided precision flap surgery and report the preliminary clinical application.Methods:The theory of CTA guided precision flap surgery is: based on CTA high-throughput data, comprehensively evaluate the wound and potential donor sites, and select the best plan for wound repair. This article reviews 177 patients treated under the guidance of CTA guided precision flap surgery from August 2014 to December 2018. Among them, 131 were males and 46 were females; they were 7-72 years old, with an average age of 39.5 years. The tissue defects were: 74 cases of foot and ankle, 64 cases of wrist, 15 cases of calf, 11 cases of forearm and upper arm, 7 cases of thigh and perineum, 5 cases of face and neck, and 1 case of abdomen. The size of the defect was 2 cm×1 cm to 65 cm×50 cm. The recipient and donor sites were assessed based on CTA guided precision flap surgery, then choose the optimal flap to repair the defect. The flap types, outcomes and complications were recorded. The visual analogue scale (VAS), British Medical Research Council sensory rating scale, and revascularization assessments of digital replantation standard by Hand Surgery Branch of Chinese Medical Association was used to assess clinical results.Results:All flaps were uneventfully harvested as planned according to the CTA guided precision flap surgery concept.A total number of 181 flaps were harvested, including 125 free flaps and 56 pedicled flaps. The flap area rangedfrom 4 cm×3 cm to 40 cm×8 cm. After surgery, 165 cases were survival completely, 7 cases were total necrosis, 9 cases were partial necrosis. A total of 174 cases of flaps survived. The mean follow-up was 9.2 months (range, 6-60 months). After surgery 53 flaps were bulky, and 7 cases with other complications.At the last follow-up, only 6 patients had mild pain, the VAS score was 1-3. The sensation of the flaps recovered partially. According to the British Medical Research Council sensory rating scale: 68 cases were grade S2 and 106 cases were grade S3. According to the revascularization assessments of digital replantation standard by Hand Surgery Branch of Chinese Medical Association, 171 cases were excellent and 3 cases were good.Conclusion:The concept of precision flap surgery based on CTA can effectively guide flap surgery and achieve precise wound repair.

Objective:To evaluate the effect of remimazolam combined with propofol for sedation in the pediatric patients undergoing outpatient root canal treatment.Methods:Seventy pediatric patients of either sex, aged 2-6 yr, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, with an expected treatment time<1 h, scheduled for elective outpatient root canal treatment, were divided into 2 groups ( n=35 each) using a random number table method: propofol group (P group) and remimazolam plus propofol group (RP group). Induction of anesthesia was as follows: propofol 1-3 mg/kg was intravenously injected until BIS value was less than 60 in group P, and remimazolam 0.2 mg/kg and propofol 1-3 mg/kg were intravenously injected until BIS value was less than 60 in group RP.Anesthesia maintenance was as follows: propofol 6-12 mg·kg -1·h -1 was intravenously infused in group P, and remimazolam 0.3 mg·kg -1·h -1 and propofol 6-12 mg·kg -1·h -1 were intravenously infused in group RP.The BIS value was maintained at 50-70 during operation.Spontaneous breathing was kept, and oxygen was inhaled through a nasal catheter with oxygen flow rate of 2-3 L/min in both groups.The amount of propofol consumed during induction and maintenance periods and the total consumption were recorded.The onset time of sedation, duration of operation, emergence time and duration of post-anesthesia care unit stay were recorded.The adverse reactions such as intraoperative respiratory depression, hypotension, bradycardia, coughing and body movement, emergence agitation and postoperative nausea and vomiting were recorded. Results:Compared with group P, the amount of propofol consumed during induction and maintenance periods and the total consumption were significantly reduced, the onset time of sedation was prolonged, the emergence time and duration of post-anesthesia care unit stay were shorted, the incidence of respiratory depression was decreased ( P<0.05), and no significant change was found in the incidence of duration of operation, hypotension, bradycardia, body movement or emergence agitation in group RP ( P>0.05). No intraoperative coughing or postoperative nausea and vomiting was found in two groups. Conclusions:The combination of remimazolam and propofol provides better efficacy than propofol alone when used for sedation in the pediatric patients undergoing outpatient dental root canal treatment.

Objective:To evaluate the sedative efficacy of S-ketamine combined with propofol for MRI examination in pediatric patients.Methods:One hundred children of both sexes, aged 1-6 yr, weighing 10-30 kg, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, who underwent MRI from February to June 2021, were selected and divided into 2 groups ( n=50 each) by a random number table method: propofol group (P group) and S-ketamine plus propofol group (K+ P group). Anesthesia induction: propofol 2.5 mg/kg was intravenously injected in group P, and S-ketamine 0.5 mg/kg and propofol 1.5 mg/kg were intravenously injected in group K+ P.Anesthesia maintenance: propofol 100 μg·kg -1·min -1 was intravenously infused, and the infusion rate of propofol was adjusted to maintain Ramsay sedation score ≥5.Propofol 0.5-1.0 mg/kg was intravenously injected and/or increasing the infusion rate of propofol when moderate and severe movement occurred.The quality of MRI images was evaluated during the examination, and the occurrence and degree of movement, airway-related adverse events (hypoxemia, apnea, upper airway obstruction, hypersalivation), hypotension and bradycardia were recorded.The average infusion rate, consumption of additional propofol for intravenous administration and total consumption of propofol were recorded.The emergence time and time of anesthesia recovery room stay were recorded.The occurrence of adverse events (vomiting, diplopia and agitation) and the parents′ satisfaction with sedative efficacy and recovery were recorded during observation in the recovery room. Results:Compared with group P, the average infusion rate of propofol, total consumption of propofol, airway-related adverse events and incidence of hypotension and bradycardia were significantly decreased ( P<0.05), and no significant change was found in the incidence and degree of body movement, quality of MRI images, emergence time and time of anesthesia recovery room stay and incidence of adverse events during recovery from anesthesia in group K+ P ( P>0.05). Conclusion:S-ketamine combined with propofol can be safely and effectively used in MRI examination in pediatric patients.

Objective:To study the respiratory morbidity and the risk factors of respiratory complications in late-preterm infants.Methods:The data of 959 late-preterm infants in 21 hospitals in Beijing from October 2015 to April 2016 were collected.These infants were divided into the respiratory morbidity group (237 cases) and the control group (722 cases) according to whether they had short-term respiratory morbidity after birth.Clinical data of the two groups were compared.Results:Among the 959 late-preterm babies, 530 were male and 429 were female.Two hundred and thirty-seven cases (24.7%) developed short-term respiratory morbidity after birth.Infectious pneumonia developed in the most cases (81 cases, 8.4%), followed by transient tachypnea (65 cases, 6.8%), amniotic fluid aspiration (51 cases, 5.3%), and respiratory distress syndrome (24 cases, 2.5%) successively.All the infants recovered and discharged.There were no differences between gender and maternal age between 2 groups (all P>0.05). Compared with the control group, more late-preterm infants were delivered by cesarean section (73.4% vs.59.7%, χ2=14.43, P<0.001) and the 1-minute Apgar score was lower [(9.41±1.66) scores vs.(9.83±0.53) scores, t=5.40, P<0.001] in the respiratory morbidity group.The differences were statistically significant.There were more cases with maternal complications in the respiratory morbidity group that in the control group (66.7% vs.58.6%, χ2=4.877, P=0.027), but no difference in various complications between 2 groups was observed ( P>0.05). In the respiratory morbidity group, the most frequent complications were maternal hypertension and preeclampsia (27.8% vs.22.6%, χ2=2.728, P=0.099). There were no differences between 2 groups in gestational age, birth weight and birth length (all P>0.05). There were more infants small for gestational age and large for gestational age in the respiratory morbidity group than in the control group (18.8% vs.14.1%, 6.3% vs.2.4%, χ2=8.960, P=0.011). The duration of hospitalization of the respiratory morbidity group was significantly longer than that of the control group [(9.00±4.42) d vs.(6.82±4.19) d, t=6.676, P<0.001] since the infants with respiratory morbidity needed to be hospita-lized. Conclusions:Respiratory diseases occur in about 1/4 of late-preterm infants.Infants who are delivered by cesarean section and whose mothers are complicated with the maternal hypertension and preeclampsia should be monitored closely.Respiratory support should be provided for infants not appropriate for gestational age who are more likely to suffer from respiratory diseases, so that they can successfully pass through the transition period.