Background::Substantial progress in air pollution control has brought considerable health benefits in China, but little is known about the spatio-temporal trends of economic burden from air pollution. This study aimed to explore their spatio-temporal features of disease burden from air pollution in China to provide policy recommendations for efficiently reducing the air pollution and related disease burden in an era of a growing economy.Methods::Using the Global Burden of Disease method and willingness to pay method, we estimated fine particulate matter (PM 2.5) and/or ozone (O 3) related premature mortality and its economic burden across China, and explored their spatio-temporal trends between 2005 and 2017. Results::In 2017, we estimated that the premature mortality and economic burden related to the two pollutants were RMB 0.94 million (68.49 per 100,000) and 1170.31 billion yuan (1.41% of the national gross domestic product [GDP]), respectively. From 2005 to 2017, the total premature mortality was decreasing with the air quality improvement, but the economic burden was increasing along with the economic growth. And the economic growth has contributed more to the growth of economic costs than the economic burden decrease brought by the air quality improvement. The premature mortality and economic burden from O 3 in the total loss from the two pollutants was substantially lower than that of PM 2.5, but it was rapidly growing. The O 3-contribution was highest in the Yangtze River Delta region, the Fen-Wei Plain region, and some western regions. The proportion of economic burden from PM 2.5 and O 3 to GDP significantly declined from 2005 to 2017 and showed a decreasing trend pattern from northeast to southwest. Conclusion::The disease burden from O 3 is lower than that of PM 2.5, the O 3-contribution has a significantly increasing trend with the growth of economy and O 3 concentration.

Objective:To analyze the duration of the second stage of labor without epidural anesthesia and its association with pregnancy outcome.Methods:This retrospective study involved 12 789 women who delivered without epidural anesthesia in the First Affiliated Hospital of Kunming Medical University from January 1, 2014 to December 31, 2017. These subjects were divided into primipara group (9 517 cases) and multipara group (3 272 cases). Demographic characteristics, maternal and neonatal outcomes and the duration of the second stage of labor were compared between the two groups using two independent samples t-test, Mann-Whitney U test and Chi-square test (Fisher's exact test). Differences in the maternal and neonatal outcomes were also analyzed among different subgroups in primiparae [length of second stage: <1 h group ( n=6 265), ≥1-2 h group ( n=2 305), ≥2-3 h group ( n=831) and ≥3 h group ( n=116)] and multiparae [length of second stage <1 h group ( n=3 144), ≥1-2 h group ( n=102) and ≥2 h group ( n=26)]. The association between second stage length and pregnancy outcomes was analyzed with Cramer's V. After adjusted for maternal age, gestational weeks at delivery, body mass index before pregnancy, complications during pregnancy and neonatal birth weight, the relationship between the duration of the second stage and adverse outcomes was analyzed by binary logistic regression analysis. Results:The 95 th percentile of the second-stage labor duration was 143 min for primiparae and 52 min for multiparae. The rates of vaginal delivery, forceps delivery, cesarean section in the second stage, episiotomy, third- or fourth-degree perineal laceration, postpartum hemorrhage, grade Ⅱ postpartum hemorrhage, transfusion, umbilical arterial blood gas pH<7.15 and transferring to neonatal intensive care unit (NICU) were all correlated with the duration of second stage in primiparae (Cramer's V values: 0.22, 0.23, 0.03, 0.22, 0.05, 0.10, 0.03, 0.03, 0.03 and 0.07, respectively, all P<0.05), and so did those of vaginal delivery, forceps delivery, episiotomy, postpartum hemorrhage, grade Ⅱ postpartum hemorrhage, transfusion and transferring to NICU in multiparae (Cramer's V values: 0.18, 0.19, 0.28, 0.14, 0.09, 0.13 and 0.06, respectively, all P<0.05). Logistic analysis showed that in primiparae, the duration of second stage >1 h was an independent risk factor for episiotomy, third- or fourth-degree perineum laceration, forceps delivery, postpartum hemorrhage, admission to NICU and umbilical arterial blood gas pH<7.15 [adjusted OR (95% CI): 2.080 (1.907-2.268), 1.773 (1.080-2.911), 1.625 (1.420-1.859), 1.365 (1.231- 1.514), 1.305 (1.165-1.462) and 1.246 (1.081-1.436), respectively], while second stage length >2 h was the independent risk factor for episiotomy, forceps delivery, third- or fourth-degree perineum laceration, postpartum hemorrhage, grade Ⅱ postpartum hemorrhage, blood transfusion, admission to NICU and umbilical arterial blood gas pH<7.15 [adjusted OR (95% CI): 4.844 (4.132-5.678), 4.223 (3.571-4.993), 3.289 (1.806-5.989), 1.952 (1.675-2.274), 1.781 (1.057-3.001), 1.654 (1.025-2.668), 1.682 (1.421-1.991) and 1.298 (1.039-1.620), respectively]. In multiparae, the length of second stage >1 h was an independent risk factor for episiotomy, blood transfusion, forceps delivery, postpartum hemorrhage and admission to NICU [adjusted OR (95% CI): 8.796 (5.717-13.534), 7.469 (2.874-19.411), 6.135 (3.217-11.699), 2.697 (1.624-4.477) and 1.814 (1.063-3.097), respectively], while the duration of second stage >2 h was the independent risk factor for episiotomy, third- or fourth-degree perineum laceration, blood transfusion, grade Ⅱ postpartum hemorrhage, forceps delivery and postpartum hemorrhage [adjusted OR (95% CI): 38.868 (14.948-101.063), 28.046 (2.780-282.490), 20.076 (5.384-74.866), 16.327 (3.406-78.274), 14.337 (5.351-38.411) and 9.036 (3.880-21.011), respectively]. Conclusions:The duration of the second stage of labor without epidural anesthesia is between that reported by Friedman and by Zhang. A prolonged second stage of labor may increase the risk of adverse pregnancy outcomes.

Objective:To investigate the circadian rhythm of blood pressure and morning blood pressure surge (MBPS) in children with neurally mediated syncope (NMS).Methods:From July 2018 to June 2019, 135 cases [aged 3-16 years old (10.12±2.53) years old, with 74 males and 61 females] with unexplained syncope, presyncope, and symptoms such as headache, dizziness, chest pain, and chest tightness were collected in the Second Xiangya Hospital, Central South University for the first time.The 24 hour ambulatory blood pressure monitoring (24 h ABPM) was completed on the same day of the head-up tilt test (HUTT). Patients were divided into HUTT negative and positive groups, and dippers and non-dippers groups. MBPS (sleep-trough surge) was calculated and compared respectively.Results:(1) There were 51 patients in the HUTT positive group, including 27 patients with vasovagal syncope, 23 patients with postural orthostatic tachycardia syndrome, and 1 patient with orthostatic hypotension. In HUTT positive group, there were 22 cases (43.14%) of dippers and 29 cases of non-dippers.There were 84 patients in the HUTT negative group, there were 32 cases (38.10%) of dippers and 52 cases of non-dippers. There were no statistical significances in the dipper proportion between HUTT positive and negative group ( χ2=1.305, P>0.05). (2) Sleep-trough systolic blood pressure (SBP) surge was 1-45 mmHg [(15.97±8.03) mmHg](1 mmHg=0.133 kPa), and sleep-trough diastolic blood pressure (DBP) surge was -6-43 mmHg[(14.05±7.97) mmHg]. There were no statistical significances in sleep-trough surge between the HUTT negative and positive group (all P>0.05). (3) The age in the dipper group was higher than that in the non-dipper group [(10.72±2.20) years old vs. (9.72±2.66) years old, t=2.288, P<0.05]. The daytime average SBP [(110.20±8.33) mmHg vs.(105.54±7.51) mmHg, t=3.381, P<0.01], and morning peak SBP [(109.99±10.19) mmHg vs.(106.63±8.71) mmHg, t=2.045, P<0.05] of the dipper group were higher than those of the non-dipper group.The nighttime average SBP[(95.41±7.50) mmHg vs.(98.59±6.88) mmHg, t=2.540, P<0.01], nighttime average DBP[(48.61±4.52) mmHg vs.(52.28±4.65) mmHg, t=4.547, P<0.01], nocturnal minimum SBP[(89.62±8.18) mmHg vs.(93.60±7.38) mmHg, t=2.940, P<0.01], and nocturnal minimum DBP[(44.99±5.32) mmHg vs.(49.01±5.54) mmHg, t=4.205, P<0.01] of the dipper group were lower than that of the non-dipper group.Nocturnal SBP reduction rate [(13.42±2.68)% vs.(6.48±2.49)%, t=15.384, P<0.01], nocturnal DBP reduction rate[(19.98±4.92)% vs.(12.46±5.05)%, t=8.561, P<0.01], sleep-trough SBP surge[(20.37±8.30) mmHg vs.(13.03±6.36) mmHg, t=5.800, P<0.01], and sleep-trough DBP surge[(16.91±8.06) mmHg vs.(12.13±7.36) mmHg, t=3.554, P<0.01] of the dipper group were higher than those of the non-dipper group. Conclusions:Nocturnal blood pressure reduction and sleep-trough surge decreased in NMS children, and there is a circadian rhythm disorder of blood pressure.

Objective:To study the diagnostic efficacy and prognostic evaluation value of QT interval dispersion (QTd) in children and adolescents with cardioinhibitory vasovagal syncope (VVS-CI).Methods:From July 2010 to January 2020, 80 children and adolescents who received their first visit or admission to the Pediatric Syncope Clinic of The Second Xiangya Hospital of Central South University and definite diagnosed of VVS-CI due to syncope or presyncope were selected as the VVS-CI group, meanwhile, 80 children and adolescents who had physical examination in the hospital were selected as the control group.QT interval were measured by 12-lead electrocardiogram at the baseline.Results:(1) Comparison between the two groups: Compared with the control group, the VVS-CI group had a significantly lower heart rate ( P<0.05) and significantly longer QT interval, such as the maximum QT interval (QTmax), minimum QT interval (QTmin), QTd, corrected maximum QT interval (QTcmax) and corrected QT interval dispersion (QTcd) ( P<0.05). After follow-up 84 (45, 127) days, compared with the responsive group, the non-responsive group had a significantly longer QT interval, such as QTmax, QTd, QTcmax, corrected minimum QT interval (QTcmin)and QTcd ( P<0.05). (2) Diagnostic efficiency: QTmax, QTmin, QTd, QTcmax and QTcd had a certain diagnostic value in children and adolescents with VVS-CI ( P<0.001). QTd had the largest area under the curve (AUC) (0.914), and had a sensitivity of 86.30% and a specificity of 84.95% at the optimal cut-off value of 28.50 ms for VVS-CI diagnosis.(3) Prognostic evaluation value: QTmax, QTd, QTcmax, QTcmin, QTcd had an estimated value for the prognosis of VVS-CI in children and adolescents ( P<0.05 or 0.01). QTd had the largest AUC (0.906) and the best cut-off value was 34.50 ms, the sensitivity to predict response to VVS-CI intervention was 90.00%, and the specificity was 82.35%. Conclusion:QTd of electrocardiogram has a good estimation value in the diagnosis and prognosis of VVS-CI in children and adolescents.

Pregnancy has increased susceptibility to H1N1 influenza virus infection. Maternal influenza infection is associated with increased risk of morbidity and mortality. A case of influenza A (H1N1) during late pregnancy (pregnancy 1, birth 0, pregnancy 30⁺² weeks) was admitted to the Second Affiliated Hospital of Kunming Medical University on December 16th, 2018. The patient was set on mechanical ventilation with a FiO₂ of 1.0, a positive end-expiratory pressure (PEEP) of 15 cmH₂O (1 cmH₂O = 0.098 kPa), and a tidal volume of 4-6 mL/kg (ideal body weight). However the pulse oxygen saturation (SpO₂) could only be maintained at about 0.85. The disease was controlled by the treatments of anti-infection, mechanical ventilation, immune therapy, nutritional support, preventive anticoagulant treatment by heparin sodium, adequate negative fluid balance, and other organ support therapy. This article introduced the treatment process of the patient in detail, and provided experience for clinical treatment.

Pregnancy has increased susceptibility to H1N1 influenza virus infection. Maternal influenza infection is associated with increased risk of morbidity and mortality. A case of influenza A (H1N1) during late pregnancy (pregnancy 1, birth 0, pregnancy 30⁺² weeks) was admitted to the Second Affiliated Hospital of Kunming Medical University on December 16th, 2018. The patient was set on mechanical ventilation with a FiO₂ of 1.0, a positive end-expiratory pressure (PEEP) of 15 cmH₂O (1 cmH₂O = 0.098 kPa), and a tidal volume of 4-6 mL/kg (ideal body weight). However the pulse oxygen saturation (SpO₂) could only be maintained at about 0.85. The disease was controlled by the treatments of anti-infection, mechanical ventilation, immune therapy, nutritional support, preventive anticoagulant treatment by heparin sodium, adequate negative fluid balance, and other organ support therapy. This article introduced the treatment process of the patient in detail, and provided experience for clinical treatment.
Female ; Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human ; Positive-Pressure Respiration ; Pregnancy ; Pregnancy Complications ; Respiratory Distress Syndrome ; Tidal Volume

Objective:To explore the relationship between unexplained palpitation in children and head-up tilt test (HUTT).Methods:A total of 142 children with the main symptom of unexplained palpitation were admitted to the Specialist Out-Patient Clinic of Children's Cardiovascular Disease from Sept.2008 to Feb.2017 in the Second Xiangya Hospital,Central South University.Among them,63 cases were male,79 cases were female,with the mean age of (10.12±2.88) years old.The detailed history,physical examinations,conventional 12 electrocardiogram,chest X-ray,echocardiography,myocardial enzymes and thyroid function were all examined.The disorders of heart disease,systemic disease and drug effect were ruled out.The HUTT inspection was then given to them.Results:Among the 142 palpitation cases,79 cases were HUTT positive (55.6％) and 63 cases were HUTT negative (44.4％).The age in HUTT positive patients was older than that in HUTT negative patients (P＜0.05),with no significant difference in gender (P＞0.05).There were three types of hemodynamic changes in HUTT positive patients.Among them,38 cases were postural orthostatic tachycardia syndrome (48.1％),36 cases were the vasovagal syncope vasodepressive type (45.6％) and 5 cases were the vasovagal syncope mixed type (6.3％).There were no hemodynamic types for vasovagal syncope cardioinhibitory type,orthostatic hypotension and orthostatic hypertension.Conclusion:Among the clinically unexplained palpitations children,more than half are caused by unbalanced autonomic nervous function.HUTT can help clear the cause of unexplained palpitations.

Objective To explore the change in 25 hydroxyvitamin D[25 -(OH)D]level in school - aged children with orthostatic hypertension (OHT). Methods Nineteen cases of school - aged children with OHT confirmed diagnosis by head - up tilt table test at the Department of Pediatric Cardiovasology,Children′s Medical Center,the Second Xiangya Hospital,Central South University,from October 2014 to February 2017,were selected as OHT group, including 17 males and 2 females,and their ages were from 7 to 14(11. 21 ± 2. 70)years old. Nineteen healthy children including 17 males and 2 females and aged 8 to 14(11. 05 ± 2. 35)years old who had a healthy examination of child care at the hospital in the same period were selected as healthy control group. In two groups of children all possible basic diseases were eliminated,such as severe liver and kidney disease,abnormal thyroid function and metabolic bone disease and/ or the long - term use of 25 -(OH)D metabolism drugs,accepted the serum 25 -(OH)D detection. Results (1)There was no significant difference in age and gender between the OHT group and the healthy control group(t = 0. 559,P > 0. 05;χ2 = 0. 000,P > 0. 05). The 25 -(OH)D levels were significantly lower in the OHT group than those in the healthy control group [(39. 62 ± 10. 65)nmol/ L vs. (64. 83 ± 10. 28)nmol/ L,t = - 7. 422,P <0. 01]. (2)25 -(OH)D levels had no correlation with age,gender,height,body mass,systolic pressure,or diastolic blood pressure (r = 0. 254,0. 047,0. 195,0. 019,- 0. 191,- 0. 184,all P > 0. 05). Taking 25 -(OH)D level as dependent variable,age,gender,height,body mass,systolic pressure,diastolic blood pressure as independent variables, multiple stepwise regression equation to predict 25 -(OH)D level was not fit. Conclusion Lower level of 25 -(OH)D may be one of the mechanisms for the onset of the school - aged children with OHT.

Objective To investigate the changes in creatine kinase (CK) and its isoenzymes (CK-MB) in children and adolescents with vasovagal syncope (VVS).Methods The VVS group included 150 patients with unexplained syncope or prodromata[69 males and 81 females,aged from 4 to 17 years old,with the average age (11.21 ±2.40) years old],who had been diagnosed as VVS by using head-up tilt table test(HUTT) in the Second Xiangya Hospital,Central South University from October 2015 to August 2017.The healthy control group included 99 healthy children [58 males and 41 females,aged from 4 to 17 years old,with the average age (10.78 ± 2.26)years old] with gender and age-matched.The differences in serum CK and CK-MB levels between 2 groups were compared,and receiver operating characteristic (ROC) curve was used to explore the predictive value of CK and CK-MB for diagnosing VVS.Results (1) Compared with the healthy control group,both CK [(93.77 ± 33.01) U/L vs.(125.02 ± 58.06) U/L] and CK-MB [(21.31 ± 6.99) U/L vs.(26.93 ± 8.78) U/L] levels decreased in the VVS group,and there were statistically significant differences(all P ＜0.05).When the value of CK was 89.22 U/L,the sensitivity to diagnostic VVS was 76.80％,and the specificity was 54.70％;while the value of CK-MB was 23.93 U/L,the sensitivity to diagnostic VVS was 66.70％,and the specificity was 71.30％.(2) In VVS group,the CK levels of the females were significantly lower than those of the males [(85.25 ± 29.43) U/L vs.(103.77 ± 34.36) U/L],and there was a statistical difference (P ＜ 0.05);while there was no significant difference in CK-MB between the males and the females in VVS group.(3) There were no significant differences between 3 types of VVS (all P＞0.05).Compared with the healthy control group,CK decreased in all the 3 types of VVS (all P ＜ 0.05),while CK-MB decreased only in the vasodepressor type and mixed type (all P ＜ 0.05).Conclusions Compared with the healthy children and adolescents,the serum CK and CK-MB levels will decrease in children with VVS,which indicates that CK and CK-MB may be involved in the pathogenesis of VVS.

Objective To retrospectively analyze the etiology and prognosis of the children and adolescents with situational syncope in a single center.Methods There were 4 274 cases of children and adolescents [aged from 2 to 18 years old,the average age being (10.82 ± 3.13)years old],male 2 208 cases,female 2 066 cases with ortho-static intolerance syndromes,such as unexplained syncope or symptoms of presyncope,etc,who were treated at Children's Syncope Outpatient Department or Inpatient Department in the Second Xiangya Hospital,Central South University from January 2000 to November 2017.All subjects underwent detailed history investigation,careful physical examinations, routine 12-lead electrocardiogram,Holter electrocardiogram(ECG),chest X-ray,echocardiography,electroencephalo-gram(EEG)and head computerized tomography(CT)or magnetic resonance imaging(MRI),blood biochemical exami-nation (including fasting glucose,myocardial enzymes)and organic diseases in the heart,brain,blood vessels were ex-cluded,but the cause of syncope was still not clear.The head-up tilt table test (HUTT)was performed after the pa-tients or/and the families wrote the informed consent agreement.Results A total of 177 (4.14%)patients with situa-tional syncope were diagnosed among 4 274 cases.Etiology included the abdominal musecle exercise (35.59%,63/177 cases),urination (24.29%,43/177 cases),bathing (9.60%,17/177 cases),defecation (7.34%,13/177 cases), singing (5. 08%,9/177 cases),rides (4.52%,8/177 cases),blood-injection-injury phobia (3.95%,7/177 ca-ses),swallowing (3.39%,6/177 cases),and hair-grooming (2. 82%,5/177 cases),syncope during acupuncture treatment (2. 26%,4/177 cases),and cough (1.13%,2/177 cases). The common positions were upright position (84.18%,149/177 cases),squatting to standing position (8.47%,15/177 cases),sitting position (5.08%,9/177 cases),and squatting position (2.26%,4/177 cases).HUTT positive rate was 69.49%(123/177 cases),common type of hemodynamic were the vasodepressive type of vasovagal syncope (45.20%,80/177 cases),mixed type of vaso-vagal syncope (19.77%,35/177 cases),postural orthostatic tachycardia syndrome (3.39%,6/177 cases)and the cardiac suppressive type of vasovagal syncope (1.13%,2/177 cases).In 35 cases of situational syncope,the number of children and adolescents with syncope was significantly reduced by health education and upstanding training.By the first follow-up review,the cases were reduced from (2.69 ± 1.81)times to (0.59 ± 0.96)times after healthy edu-cation of 2-16 weeks [(4.97 ± 3.16)weeks].By the second follow-up review,3 out of 8 cases did not faint,3 cases fainted 1 time,1 case fainted 2 times,and 1 case fainted 4 times.The outcomes of the first reexamination of HUTT in 16 cases were negative,and other 3 cases were negative by twice visit.Conclusions The etiology of children and adoles-cents are flag-raising(abdominal muscle exercise),urination,bathing,defecation,singing,riding,blood-injection-injury phobia,swallowing,hair -grooming,syncope during acupuncture treatment and coughing. Healthy education is good for situational syncope.