Objective To investigate the influence of acute hypervolemic hemodilution (AHH) on pharmacodaynamics of cisatracurium in patients undergoing general anesthesia. Methods Sixty ASA Ⅰ or Ⅱ patients aged 18-60 yr scheduled for major abdominal surgery under general anesthesia were randomly allocated into 2 groups (n = 30 each): control group and AHH group. Each group was further divided into 3 subgroups according to the initial dose of cisatracurium (30, 40, 50 μg/kg) . The radial artery and right internal jugular vein were cannulated. BP, HR, CVP, SpO_2, P_(ET) CO_2 and body temperature were continuously monitored. The response of left adductor pollicis muscle to TOF stimulation of ulna nerve was monitored using TOF- Watch~R SX (Organon). Both groups received 10 ml/kg multiple electrolyte solution (plasma-Lyte A) during induction of anesthesia. In group AHH 15 ml/kg 6% hydroxyethyl starch (HES) 130/0.4 solution was infused via internal jugular vein over 30-40 min in addition to plasma-Lyte A. Five minutes after completion of plasma-Lyte A or HES, cisatracurium 30, 40 or SO fig/kg was injected iv in the respective subgroups. After the maximal T_1 block was achieved, the second dose was given to reach a total dose of 100 μg/kg. The onset time, duration of clinical action, total duration of action and recovery index were recorded. The doses for 50% , 90% and 95% T_1 depression (ED_(50), ED_(90), ED_(95)) were calculated by Probit method. Results The ED_(50), ED_(90), ED_(95) of cisatracurium were significantly higher in AHH group than in control group. The onset time of cisatracurium was significantly longer but clinical and total duration of action was significantly shorter in AHH group than in control group. There was no significant difference in recovery index between the two groups. Conclusion AHH can decrease the potency of cisatracurium.

Objective To establish a rabbit model of acute lung injury induced by one-lung ventilation (OLV) .Methods Sixteen New Zealand white rabbits weighing 2.3-2.7 kg were randomly divided into 2 groups (n=8 each):conventional tidal volume(VT) group (group Ⅰ) and high VT group (group Ⅱ).All the rabbits were tracheostomized and a tracheal tube was inserted into the right bronchus for right lung ventilation in the two groups. VT was set at 6 ml/kg in group Ⅰ and at 12 ml/kg in group Ⅱ and the other ventilatory parameters were the same in the two groups (FiO2 50% , RR 40 bpm, I∶E=1∶2). Immediately before OLV(T0) and at 1, 2 and 3 h of OLV (T1-3), peak airway pressure was measured and arterial blood samples were taken for blood gas analysis and oxygenation index (OI) was calculated. The animals were sacrificed at 3 h of OLV and lung tissues obtained for microscopic examination.The lung injury was scored. W/D lung weight ratio was calculated. Bron-choalveolar lavage fluid (BALF) was collected for measurement of protein concentrations and neutrophil counts. Results The peak airway pressure was significantly higher at T1-3 in group Ⅱ and OI was significantly lower at T2,3 in the two groups than those at T0(P＜0.05) .W/D lung weight ratio and lung injury scores of the right lung were significantly lower than those of the left lung in the two groups(P＜0.05).The peak airway pressure was significantly higher at T1-3, OI was significantly lower at T3, and W/D lung weight ratio, protein concentrations and neutrophil counts in BALF and lung injury scores of the right lung were significantly higher in group Ⅱ than in group Ⅰ(P＜0.05). Conclusion OLV with VT of 12 ml/kg for 3 h can successfully establish a rabbit model of acute lung injury.

Objective:To analyze the prognostic factors and evaluate the accuracy of existing survival prediction models in patients with lung cancer-derived spinal metastases who have undergone open surgery.Methods:According to the inclusion criteria, the data of 76 patients with spinal metastasis of lung cancer who underwent open surgery in the department of Orthopedics in Guangdong Provincial People's Hospital were collected from January 2019 to November 2021. The relationship between the number of bone metastasis, pathological type, visceral metastasis, epidermal growth factor receptor mutation, serum alkaline phosphatase (ALP), hemoglobin (Hb), Frankel grade and postoperative survival time in 76 cases was analyzed by Cox logical regression analysis and Kaplan-Meier method to determine the potential prognostic factors. The accuracy of Tomita score, Tokuhashi revised score, Katagiri New score, New England Spinal Metastasis Score score (NESMS) and Skeletal Oncology Research Group (SORG) machine learning algorithm in predicting postoperative survival time was verified by drawing receiver operating characteristic (ROC) curve.Results:The median follow-up time of the patients was 18.0 months (2.3-36.0 months). The median survival time was 12.6 months [95% CI (10.8, 14.4)]. The survival rates at 6 and 12 months after operation were 71.6% and 52.0%, respectively. Multivariate regression analysis showed that ALP [ HR=0.23, 95% CI (0.11, 0.48), P<0.001], Hb [ HR=4.48, 95% CI (2.07, 9.70), P< 0.001] and EGFR mutation [ HR=2.22, 95% CI (1.04, 4.76), P=0.040] were independent predictors of prognosis. The accuracy of Tomita score, Tokuhashi revised score (2005), Katagiri New score and NESMS score in predicting 1-year mortality was 58.7%, 65.7%, 70.5% and 65% respectively, and the accuracy in predicting 6-month mortality was 63.7%, 62.2%, 61.2% and 56.8% respectively. The accuracy of SORG machine learning algorithm in predicting 1-year and 90 d mortality was 81.1%, 67.5%, respectively. Conclusion:No EGFR mutation, ALP>164 U/L and Hb≤125 g/L were risk factors affecting the survival of patients with spinal metastasis of lung cancer. SORG machine learning algorithm has good accuracy in predicting the postoperative survival rate of patients with lung cancer spinal metastasis.

【Objective】 To clarify the hematological characteristics and current situation of chronic mountain sickness among Tibetan residents in extreme high altitude area (more than 5 000 m above the sea level) of Ali district based on the analysis of physical examination and blood test results. 【Methods】 Totally 250 Tibetan residents were selected by convenient sampling for blood oxygen saturation (SpO2), heart rate, and blood routine examination. Chronic mountain sickness was determined according to the hemoglobin (Hb) level and SpO2. 【Results】 The red blood cell (RBC), Hb and hematocrit (HCT) of the Tibetan residents at 5 200-meter altitude were all higher than the normal physiological reference range of China. Mean red blood cell volume (MCV), mean red blood cell hemoglobin content (MCH), mean red blood cell hemoglobin concentration (MCHC), white blood cell (WBC) and platelet (PLT) were in the upper limit of the reference value. The RBC, Hb, HCT and MCHC of male Tibetan residents were higher than those of females, while PLT was lower than that of females, with significant differences. There were no statistical differences in MCV, MCH or WBC among different genders of Tibetan residents. The SpO2 of the Tibetan residents was about 85% of the normal value, and the males had higher SpO2 than the females in the same age group, and the difference was statistically significant, but the heart rate did not differ significantly. The prevalence rate of chronic mountain sickness in this area was as high as 16.4%, and the prevalence rate of heavy manual workers was significantly higher than that of light manual workers, with significant differences. 【Conclusion】 The high-altitude anoxic environment causes the changes in red blood cells, hemoglobin, and oxygen saturation of local residents, and the prevalence of chronic mountain sickness increases significantly. Labor intensity is one of the risk factors for chronic mountain sickness in high-altitude areas.