Objective:To compare the efficacy of posteromedial combined with lateral Frosch approach versus anterior medial and lateral dual incision approach in open reduction and internal fixation for Schatzker type VI tibial plateau fractures.Methods:A retrospective cohort study was conducted to analyze the clinical data of 41 patients with Schatzker type VI tibial plateau fractures, who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from January 2018 to May 2024, including 23 males and 18 females, aged 34-79 years [(50.7±7.7)years]. Twenty-three patients underwent open reduction and internal fixation via the posteromedial combined with lateral Frosch approach (posterior approach group), while 18 patients underwent the same procedure via the anterior medial and lateral dual incision approach (anterior approach group). The following parameters were compared between the two groups: operation duration, intraoperative blood loss, postoperative drainage volume, depth of articular surface depression and tibial plateau width measured preoperatively, at 7 days, 3 months postoperatively, and at the last follow-up, medial proximal tibial angle (MPTA) and posterior proximal tibial angle (PPTA) measured at 7 days, 3 months postoperatively, and at the last follow-up, visual analogue scale (VAS) scores assessed preoperatively, at 7 days postoperatively, and at the last follow-up, American Knee Society (KSS) score and knee flexion range of motion assessed at 7 days, 3 months postoperatively, and at the last follow-up, fracture healing status at the last follow-up, and incidence of postoperative complications.Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operation duration was (119.6±11.8)minutes in the posterior approach group, which was significantly shorter than (140.3±10.6)minutes in the anterior approach group ( P<0.05). There were no statistically significant differences in intraoperative blood loss or postoperative drainage volume between the two groups ( P>0.05). No significant differences were found in the preoperative depth of articular surface depression or tibial plateau width between the two groups ( P>0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the depth of articular surface depression was 0.8(0.6, 1.0)mm, 0.6(0.5, 0.8)mm, and 0.6(0.5, 0.7)mm in the posterior approach group, which were significantly shorter than 1.1(0.9, 1.3)mm, 0.8(0.7, 1.0)mm, and 0.8(0.7, 1.0)mm in the anterior approach group ( P<0.05). The tibial plateau width at the same time points was 71.0(69.1, 73.5)mm, 70.5(69.2, 72.9)mm, and 70.5(69.3, 72.5)mm in the posterior approach group, which were significantly shorter than 73.0(72.3, 74.2)mm, 71.5(71.0, 73.0)mm, and 71.5(71.1, 72.6)mm in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the MPTA values were (87.4±0.7)°, (87.7±0.6)°, and (87.9±0.5)° in the posterior approach group, which were significantly larger than (85.2±2.5)°, (86.0±2.2)°, and (86.3±2.0)° in the anterior approach group ( P<0.01). The PPTA values at the same time points were (9.5±0.7)°, (9.0±0.5)°, and (8.6±0.4)° in the posterior approach group, which were significantly smaller than (11.2±1.0)°, (10.3±0.8)°, and (9.8±0.7)° in the anterior approach group ( P<0.01). There was no significant difference in the preoperative VAS score between the two groups ( P>0.05). At 7 days postoperatively and at the last follow-up, the VAS scores were 4.0(3.0, 5.0)points and 0.5(0.0, 2.0)points in the posterior approach group, which were significantly lower than 5.0(4.0, 5.0)points and 1.0(1.0, 3.0)points in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the KSS scores were 62.5(57.0, 67.5)points, 75.5(72.0, 82.5)points, and 87.0(82.5, 93.5)points in the posterior approach group, which were significantly higher than 61.5(54.5, 63.0)points, 74.0(68.0, 79.0)points, and 85.5(78.0, 88.5)points in the anterior approach group ( P<0.05). The knee flexion range of motion was 90.0(85.0, 95.0)°, 115.0(109.0, 122.0)°, and 126.0(120.0, 130.0)° in the posterior approach group, which were significantly greater than 80.5(75.2, 85.8)°, 110.0(104.0, 115.0)°, and 119.0(113.0, 122.0)° in the anterior approach group ( P<0.05). At the last follow-up, all the fractures were healed in both groups. No statistically significant difference was found in the incidence of postoperative complications between the two groups ( P>0.05). Conclusion:Compared to the anterior medial and lateral dual incision approach, the posteromedial combined with lateral Frosch approach demonstrates superior advantages in operation duration, reduction quality, pain relief, functional recovery in the treatment of Schatzker type VI tibial plateau fractures, while the incidence of complications is comparable.

Objective:To investigate the efficacy of cementless long-stem total hip arthroplasty (THA) in the treatment of end-stage osteonecrosis of the femoral head (ONFH) combined with ipsilateral subtrochanteric femoral fractures.Methods:A retrospective case series study was conducted on 18 patients with end-stage ONFH combined with ipsilateral subtrochanteric fractures who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from January 2016 to June 2023, including 8 males (8 hips) and 10 females (10 hips), aged 56-79 years [(69.4±7.0)years]. All the patients had Association Research Circulation Osseous (ARCO) stage IV ONFH combined with ipsilateral subtrochanteric fracture (Seinsheimer types II-IV). Parameters recorded included operation duration, intraoperative blood loss, length of hospital stay, time to partial weight-bearing, and time to full weight-bearing. Vertical offset and leg length discrepancy (LLD) were compared preoperatively and at 1 week postoperatively. Visual analogue scale (VAS) score, hip range of motion (flexion, abduction), and Harris hip score (HHS) were compared preoperatively, at 1 week, 3 months postoperatively, and at the last follow-up. Perioperative complications were observed.Results:All the patients were followed up for 12-70 months [(36.4±16.2)months]. Operation duration was (116.4±18.1)minutes. Intraoperative blood loss was (334.4±121.3)ml. The length of hospital stay was 13.0(10.0, 16.3)days. The time to partial weight-bearing was 5.0(3.0, 7.0)days, with time to full weight-bearing for 5.0(4.0, 5.3)weeks. At 1 week postoperatively, the vertical offset [(58.9±4.1)mm] was significantly increased compared to that preoperatively [(49.3±3.3)mm] ( P<0.01), while the LLD [(4.2±3.1)mm] was significantly reduced compared to that preoperatively [(16.2±5.8)mm] ( P<0.01). At 1 week, 3 months postoperatively and at the last follow-up, the VAS scores [3.0(2.0, 3.3)points, 2.0(1.0, 2.0)points, and 1.0(0.0, 2.0)points] were significantly lower than that preoperatively [6.0(5.0, 6.3)points], and decreased with the passage of follow-up time ( P<0.01); the hip flexion angles [(50.4±6.5)°, (94.3±6.4)°, and (104.7±7.4)°] and hip abduction angles [(21.5±4.4)°, (34.9±4.5)°, and (42.9±4.9)°] were lower than those preoperatively [(32.9±6.4)° and (13.4±4.9)°], and decreased with the passage of follow-up time ( P<0.01); the HHS [(58.1±4.9)points, (83.1±2.9)points, and (90.7±2.6)points] were higher than that preoperatively [(33.4±4.4)points], and increased with the passage of follow-up time ( P<0.01). At the last follow-up, 5 patients were rated as excellent, 11 as good, and 2 as fair according to the HHS criteria, with an overall excellent and good rate of 89%. No perioperative complications were observed, including neurovascular injury, secondary fracture, or infection. One patient developed partial deep vein thrombosis of the lower extremity (the popliteal vein) at 2 weeks after surgery, which recovered completely following treatment with a standard oral administration of rivaroxaban, etc. At the last follow-up, no evidence of malunion, prosthesis loosening, subsidence, or dislocation was observed. Conclusion:The use of cementless long-stem THA in the treatment of end-stage ONFH combined with ipsilateral subtrochanteric fractures has advantages of small trauma, early weight-bearing, early pain relief, improved joint motion and function, and few complications.

Objective:To compare the efficacy of posteromedial combined with lateral Frosch approach versus anterior medial and lateral dual incision approach in open reduction and internal fixation for Schatzker type VI tibial plateau fractures.Methods:A retrospective cohort study was conducted to analyze the clinical data of 41 patients with Schatzker type VI tibial plateau fractures, who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from January 2018 to May 2024, including 23 males and 18 females, aged 34-79 years [(50.7±7.7)years]. Twenty-three patients underwent open reduction and internal fixation via the posteromedial combined with lateral Frosch approach (posterior approach group), while 18 patients underwent the same procedure via the anterior medial and lateral dual incision approach (anterior approach group). The following parameters were compared between the two groups: operation duration, intraoperative blood loss, postoperative drainage volume, depth of articular surface depression and tibial plateau width measured preoperatively, at 7 days, 3 months postoperatively, and at the last follow-up, medial proximal tibial angle (MPTA) and posterior proximal tibial angle (PPTA) measured at 7 days, 3 months postoperatively, and at the last follow-up, visual analogue scale (VAS) scores assessed preoperatively, at 7 days postoperatively, and at the last follow-up, American Knee Society (KSS) score and knee flexion range of motion assessed at 7 days, 3 months postoperatively, and at the last follow-up, fracture healing status at the last follow-up, and incidence of postoperative complications.Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operation duration was (119.6±11.8)minutes in the posterior approach group, which was significantly shorter than (140.3±10.6)minutes in the anterior approach group ( P<0.05). There were no statistically significant differences in intraoperative blood loss or postoperative drainage volume between the two groups ( P>0.05). No significant differences were found in the preoperative depth of articular surface depression or tibial plateau width between the two groups ( P>0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the depth of articular surface depression was 0.8(0.6, 1.0)mm, 0.6(0.5, 0.8)mm, and 0.6(0.5, 0.7)mm in the posterior approach group, which were significantly shorter than 1.1(0.9, 1.3)mm, 0.8(0.7, 1.0)mm, and 0.8(0.7, 1.0)mm in the anterior approach group ( P<0.05). The tibial plateau width at the same time points was 71.0(69.1, 73.5)mm, 70.5(69.2, 72.9)mm, and 70.5(69.3, 72.5)mm in the posterior approach group, which were significantly shorter than 73.0(72.3, 74.2)mm, 71.5(71.0, 73.0)mm, and 71.5(71.1, 72.6)mm in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the MPTA values were (87.4±0.7)°, (87.7±0.6)°, and (87.9±0.5)° in the posterior approach group, which were significantly larger than (85.2±2.5)°, (86.0±2.2)°, and (86.3±2.0)° in the anterior approach group ( P<0.01). The PPTA values at the same time points were (9.5±0.7)°, (9.0±0.5)°, and (8.6±0.4)° in the posterior approach group, which were significantly smaller than (11.2±1.0)°, (10.3±0.8)°, and (9.8±0.7)° in the anterior approach group ( P<0.01). There was no significant difference in the preoperative VAS score between the two groups ( P>0.05). At 7 days postoperatively and at the last follow-up, the VAS scores were 4.0(3.0, 5.0)points and 0.5(0.0, 2.0)points in the posterior approach group, which were significantly lower than 5.0(4.0, 5.0)points and 1.0(1.0, 3.0)points in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the KSS scores were 62.5(57.0, 67.5)points, 75.5(72.0, 82.5)points, and 87.0(82.5, 93.5)points in the posterior approach group, which were significantly higher than 61.5(54.5, 63.0)points, 74.0(68.0, 79.0)points, and 85.5(78.0, 88.5)points in the anterior approach group ( P<0.05). The knee flexion range of motion was 90.0(85.0, 95.0)°, 115.0(109.0, 122.0)°, and 126.0(120.0, 130.0)° in the posterior approach group, which were significantly greater than 80.5(75.2, 85.8)°, 110.0(104.0, 115.0)°, and 119.0(113.0, 122.0)° in the anterior approach group ( P<0.05). At the last follow-up, all the fractures were healed in both groups. No statistically significant difference was found in the incidence of postoperative complications between the two groups ( P>0.05). Conclusion:Compared to the anterior medial and lateral dual incision approach, the posteromedial combined with lateral Frosch approach demonstrates superior advantages in operation duration, reduction quality, pain relief, functional recovery in the treatment of Schatzker type VI tibial plateau fractures, while the incidence of complications is comparable.

Objective:To investigate the efficacy of cementless long-stem total hip arthroplasty (THA) in the treatment of end-stage osteonecrosis of the femoral head (ONFH) combined with ipsilateral subtrochanteric femoral fractures.Methods:A retrospective case series study was conducted on 18 patients with end-stage ONFH combined with ipsilateral subtrochanteric fractures who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from January 2016 to June 2023, including 8 males (8 hips) and 10 females (10 hips), aged 56-79 years [(69.4±7.0)years]. All the patients had Association Research Circulation Osseous (ARCO) stage IV ONFH combined with ipsilateral subtrochanteric fracture (Seinsheimer types II-IV). Parameters recorded included operation duration, intraoperative blood loss, length of hospital stay, time to partial weight-bearing, and time to full weight-bearing. Vertical offset and leg length discrepancy (LLD) were compared preoperatively and at 1 week postoperatively. Visual analogue scale (VAS) score, hip range of motion (flexion, abduction), and Harris hip score (HHS) were compared preoperatively, at 1 week, 3 months postoperatively, and at the last follow-up. Perioperative complications were observed.Results:All the patients were followed up for 12-70 months [(36.4±16.2)months]. Operation duration was (116.4±18.1)minutes. Intraoperative blood loss was (334.4±121.3)ml. The length of hospital stay was 13.0(10.0, 16.3)days. The time to partial weight-bearing was 5.0(3.0, 7.0)days, with time to full weight-bearing for 5.0(4.0, 5.3)weeks. At 1 week postoperatively, the vertical offset [(58.9±4.1)mm] was significantly increased compared to that preoperatively [(49.3±3.3)mm] ( P<0.01), while the LLD [(4.2±3.1)mm] was significantly reduced compared to that preoperatively [(16.2±5.8)mm] ( P<0.01). At 1 week, 3 months postoperatively and at the last follow-up, the VAS scores [3.0(2.0, 3.3)points, 2.0(1.0, 2.0)points, and 1.0(0.0, 2.0)points] were significantly lower than that preoperatively [6.0(5.0, 6.3)points], and decreased with the passage of follow-up time ( P<0.01); the hip flexion angles [(50.4±6.5)°, (94.3±6.4)°, and (104.7±7.4)°] and hip abduction angles [(21.5±4.4)°, (34.9±4.5)°, and (42.9±4.9)°] were lower than those preoperatively [(32.9±6.4)° and (13.4±4.9)°], and decreased with the passage of follow-up time ( P<0.01); the HHS [(58.1±4.9)points, (83.1±2.9)points, and (90.7±2.6)points] were higher than that preoperatively [(33.4±4.4)points], and increased with the passage of follow-up time ( P<0.01). At the last follow-up, 5 patients were rated as excellent, 11 as good, and 2 as fair according to the HHS criteria, with an overall excellent and good rate of 89%. No perioperative complications were observed, including neurovascular injury, secondary fracture, or infection. One patient developed partial deep vein thrombosis of the lower extremity (the popliteal vein) at 2 weeks after surgery, which recovered completely following treatment with a standard oral administration of rivaroxaban, etc. At the last follow-up, no evidence of malunion, prosthesis loosening, subsidence, or dislocation was observed. Conclusion:The use of cementless long-stem THA in the treatment of end-stage ONFH combined with ipsilateral subtrochanteric fractures has advantages of small trauma, early weight-bearing, early pain relief, improved joint motion and function, and few complications.

Objective:To develop and evaluate the efficacy and safety of a three-dimensional (3D) digestive endoscope for gastric endoscopic submucosal dissection (ESD) through animal experiments.Methods:Two Dutch pigs were utilized from the Zhengzhou University Animal Experiment Center for the study. ESD procedures were performed by two senior endoscopists, one using 3D glasses and the other utilizing a 3D high-definition head display. The success of ESD was assessed based on predefined criteria, including completion of surgical steps, complete detachment of the presumptive lesion, and effective bleeding control during and after the surgery. The number of successful procedures and incidences of perforation were recorded. The stereoscopic experience of the endoscopists, including both the primary endoscopist and the assistant, was also evaluated. Furthermore, the assessment encompassed any reported symptoms of eye discomfort, such as eye fatigue, ocular pain, and blurred vision. Additionally, the confidence level of the endoscopists in the mechanical aspects of the operation, as well as encountered issues during the endoscopic procedures, were documented.Results:Two ESD were successful and no perforation occurred. Feedback from endoscopists suggested that 3D digestive endoscopy offered clear images with enhanced three-dimensionality during surgery, clear sense of distance and layering, allowing for a precise judgment of bleeding points, which surpassed 2D capabilities. No eye discomfort was experienced by endoscopists or assistants during or after the procedures. While endoscopists exhibited high confidence in 3D digestive endoscopy, they noted issues with image blurring when the camera was positioned less than 10 mm from the gastrointestinal tract wall.Conclusion:Preliminary results show that 3D digestive endoscopes can provide excellent stereo imaging, improved positioning accuracy, and safety during live animal stomach ESD procedures, without significantly increasing endoscopists' eye discomfort. Nevertheless, efforts are needed to address image blurring concerns when the camera is close to the gastrointestinal tract wall.

Objective:To develop a robotic digestive endoscope system (RDES) and to evaluate its feasibility, safety and control performance by experiments.Methods:The RDES was designed based on the master-slave control system, which consisted of 3 parts: the integrated endoscope, including a knob and button robotic control system integrated with a gastroscope; the robotic mechanical arm system, including the base and arm, as well as the endoscopic advance-retreat control device (force-feedback function was designed) and the endoscopic axial rotation control device; the control console, including a master manipulator and an image monitor. The operator sit far away from the endoscope and controlled the master manipulator to bend the end of the endoscope and to control advance, retract and rotation of the endoscope. The air supply, water supply, suction, figure fixing and motion scaling switching was realized by pressing buttons on the master manipulator. In the endoscopy experiments performed on live pigs, 5 physicians each were in the beginner and advanced groups. Each operator operated RDES and traditional endoscope (2 weeks interval) to perform porcine gastroscopy 6 times, comparing the examination time. In the experiment of endoscopic circle drawing on the inner wall of the simulated stomach model, each operator in the two groups operated RDES 1∶1 motion scaling, 5∶1 motion scaling and ordinary endoscope to complete endoscopic circle drawing 6 times, comparing the completion time, accuracy (i.e. trajectory deviation) and workload.Results:RDES was operated normally with good force feedback function. All porcine in vivo gastroscopies were successful, without mucosal injury, bleeding or perforation. In beginner and advanced groups, the examination time of both RDES and ordinary endoscopy tended to decrease as the number of operations increased, but the decrease in time was greater for operating RDES than for operating ordinary endoscope (beginner group P=0.033; advanced group P=0.023). In the beginner group, the operators operating RDES with 1∶1 motion scaling or 5∶1 motion scaling to complete endoscopic circle drawing had shorter completion time [1.68 (1.40, 2.17) min, 1.73 (1.47, 2.37) min VS 4.13 (2.27, 5.16) min, H=32.506, P<0.001], better trajectory deviation (0.50±0.11 mm, 0.46±0.11 mm VS 0.82±0.26 mm, F=38.999, P<0.001], and less workload [42.00 (30.00, 50.33) points, 43.33 (35.33, 54.00) points VS 52.67 (48.67, 63.33) points, H=20.056, P<0.001] than operating ordinary endoscope. In the advanced group, the operators operating RDES with 1∶1 or 5∶1 motion scaling to complete endoscopic circle drawing had longer completion time than operating ordinary endoscope [1.72 (1.37, 2.53) min, 1.57 (1.25, 2.58) min VS 1.15 (0.86, 1.58) min, H=13.233, P=0.001], but trajectory deviation [0.47 (0.13, 0.57) mm, 0.44 (0.39, 0.58) mm VS 0.52 (0.42, 0.59) mm, H=3.202, P=0.202] and workload (44.62±21.77 points, 41.24±12.57 points VS 44.71±17.92 points, F=0.369, P=0.693) were not different from those of the ordinary endoscope. Conclusion:The RDES enables remote control, greatly reducing the endoscopists' workload. Additionally, it gives full play to the cooperative motion function of the large and small endoscopic knobs, making the control more flexible. Finally, it increases motion scaling switching function to make the control of endoscope more flexible and more accurate. It is also easy for beginners to learn and master, and can shorten the training period. So it can provide the possibility of remote endoscopic control and fully automated robotic endoscope.

Objective:To investigate the clinicopathological features and prognostic factors of primary mediastinal large B-cell lymphoma (PMBL).Methods:The clinical data of 60 patients with PMBL including 44 biopsy cases and 16 consultation cases from September 2000 to November 2019 in the Department of Pathology, China-Japan Friendship Hospital (14 cases) and Peking Union Medical College Hospital (46 cases) were enrolled. Pathologic features, immunophenotype, immunoglobulin (Ig) gene rearrangement and microRNA expression profile were retrospectively studied.Results:Of the 60 patients, 23 were males and 37 were females, age ranged from 15 to 64 years (median 28 years). Immunohistochemical staining showed that the tumor cells were positive for pan-B cell antigens, CD30 (77.4%, 24/31), CD23 (73.1%, 19/26), MUM1 (45.8%, 11/24), Ki-67 index ≥70 % (90.6%, 29/32). EBER in situ hybridization was analyzed in 21 PMBL, only one case (4.8%) was positive. Ig gene rearrangement was performed in 20 cases, and seven were positive (35.0%). MicroRNA gene expression profiles were analyzed in seven cases of PMBL and nine cases of diffuse large B-cell lymphoma, and there were 33 microRNAs with significant difference ( P<0.05). Univariate analysis indicated that the poor prognostic factors included serum lactate dehydrogenase (LDH) level,International Prognostic Index (IPI) score ≥3, stages Ⅲ-Ⅳ, chemotherapy not combined with rituximab and MUM1 positivity ( P<0.05). Multivariate analysis showed that the treatment combined with rituximab was independently related to prognosis ( P<0.05). Conclusions:PMBL is different from diffuse large B-cell lymphoma in clinicopathologic features, immunophenotypic presentation and molecular features. The prognostic factors, molecular genetics and immunological characteristics reveal that this study has enriched our understanding of the biology of PMBL, thus providing evidence and strategies for treatment.

Objective:To evaluate the association between the use of emergency medical services (EMS) and the severity of disease among patients admitted to the emergency room, to analyze the characteristics of the patients, and to build prediction model providing evidence-based use of EMS resources.Methods:The data of patients admitted to the Emergency Room of the First Affiliated Hospital of University of Science and Technology of China from January 2020 to July 2021 were extracted from the Chinese Emergency Triage Assessment and Treatment (CETAT) database. Patients were divided into the EMS use group (AB+ group) and self-seeing group (AB-group) according to whether they used EMS. The patients’ general condition, vital signs and laboratory tests results were recorded. The severity of patients’ condition was judged based on whether the patient was admitted to the department of critical medicine, specialized care unit, emergency operation and/or emergency percutaneous intervention. A 9-variable model that did not require laboratory inspection and 22-variable model that required laboratory inspection were established to correct the propensity score to analyze the correlation between the severity of disease and the EMS use. In the subgroup analysis, the correlation between the EMS use and severity of the patients was analyzed according to the reason of the patient’s visit.Results:During the study period, 16 489 patients were admitted to the emergency room, and 6975 patients were finally enrolled in this study. There were 2768 patients (39.7%) in the AB+ group and 4207 patients (60.3%) in the AB-group. In the AB+ group 522 patients (18.9%) were in high risk, and in the AB-group 563 patients (13.4%) were in high risk. Compared with the AB-group, patients in the AB+ group were older and had a higher proportion of coma, a faster autonomic heart rate, and a lower diastolic blood pressure and peripheral oxygen saturation (SpO 2). In the 9-variable model, sex, consciousness, temperature, heart rate and diastolic blood pressure were associated with the EMS use. In the 22-variable model, consciousness, SpO 2, neutrophils, and albumin were the relevant factors for patients using EMS. Before the correction of propensity score, the EMS use was an independent risk factor for critically ill patients ( OR=1.5, 95% CI 1.32-1.72, P<0.001). After adjusted using 9-variable propensity score, the EMS use ratio decreased significantly compared with that without correction ( OR=1.24,95% CI 1.08-1.42, P<0.001). Interestingly, after adjusted with propensity score match with 22-variable model, there was no association between the severity of disease and t the EMS use ( OR=1.10,95% CI 0.95-1.28, P=0.195). In subgroup analysis, patients’ chief complaint of central nervous system, cardiovascular system, and trauma were the top three reasons at admission. Before the propensity score correction, the EMS calling patients with chief complaint of central nervous system, digestive system, and trauma were related to the severity of the patients. After adjusted with 9-variable model the EMS use was associated with the severity of the disease only in trauma patients, and after adjusted with 22-variable model there was no statistical difference considering the severity of the disease in all subgroups. Conclusions:The EMS use is common. However, the association of the EMS use with the severity of disease is decreased with variable models using propensity score. These findings indicate that the EMS use should be based on multivariable models, which may be important in detecting critically ill patients, optimizing the EMS use, and avoiding unnecessary call in the future.

Objective To understand the prevalence,treatment and influence factors of hypertension in maintenance hemodialysis (MHD) patients in Anhui Province.Methods A total of 2724 adult patients on MHD from January 1st 2014 to March 31st 2014 in 26 hospitals of southern,northern and central Anhui Province were investigated.Their demographic characteristics,primary disease,complications,medications,dialysis and laboratory examination were explored.The prevalence treatment rate and control rate of hypertension were analyzed.Associated factors for controlling hypertension [systolic blood pressure (SBP) ＜ 140 mmHg and diastolic blood pressure (DBP) ＜ 90 mmHg] were assessed by logistic regression analysis.Results (1) The prevalence of hypertension in the hemodialysis patients was 87.0％.Their treatment rate and control rate were 93.2％ and 23.9％ respectively.The average of SBP was (145.90±21.18) mmHg,and the DBP on average was (83.60± 12.21) mmHg.The most commonly used anti-hypertensive drug is calcium channel blocker (88.2％).Over one third (45.7％) of patients were treated with two kinds of anti-hypertensive drug,26.2％ with 1 kind,21.7％ with 3 kinds,and 6.4％ with 4 kinds or more.(2) Compared with non-hypertension patients,patients with hypertension have older age,higher body mass index (BMI),phosphorus,SBP and DBP,as well as lower hemoglobin and Kt/V (all P ＜ 0.05).(3) The multivariate logistic regression analysis showed that Ca ＞ 2.50 mmol/L (OR=2.084,95％CI 1.008-4.307,P=0.047) positively correlated with controlling hypertension,while smoke (OR=0.594,95％CI 0.356-0.911,P=0.046) and BMI 18.5 ～ 23.9 kg/m2 (OR=0.516,95％CI 0.293-0.907,P=0.022) negatively correlated with it.Conclusions High prevalence yet low control rate of hypertension in MHD patients in Anhui Province were observed.Hypocalcemia may be a protective factor for hypertension control,while smoke and BMI may be risk factors for it.