The neuro-prognostic value of the ion shift index in cardiac arrest patients following extracorporeal cardiopulmonary resuscitation

BACKGROUND:The ion shift index(ISI) as a prognostic indicator that can show the severity of hypoxic-ischemic injury.We aimed to evaluate the performance of the ISI in predicting unfavorable neurological outcomes at hospital discharge in cardiac arrest(CA) patients following extracorporeal cardiopulmonary resuscitation(ECPR) and to compare its performance to other prognostic predictors.METHODS:This was a retrospective observational study including adult CA patients treated with ECPR between January 2018 and December 2022 in a tertiary hospital.Data regarding clinical characteristics and laboratory parameters were collected from medical records.The ISI was determined based on the first available serum electrolyte levels after ECPR.The primary outcome was unfavorable neurological status at hospital discharge,defined as Cerebral Performance Categories 3–5.Comparisons of the characteristics between the two groups were made using the χ2 test for categorical variables and the t-test or non-parametric Mann-Whitney U-test for continuous variables,as appropriate.Correlation analysis was performed using Spearman’s rank correlation coeficient.A two-tailed P-value <0.05 was considered statistically significant.RESULTS:Among the 122 patients involved,46(37.7%) had out-of-hospital CA,and 88 had unfavorable neurological outcomes.The ISI was significantly higher in the unfavorable outcome group than in the favorable outcome group(3.74 [3.15–4.57] vs.2.69 [2.51–3.07],P<0.001).A higher ISI level was independently related to unfavorable outcome(odds ratio=6.529,95% confidence interval 2.239–19.044,P=0.001).An ISI level >3.12 predicted unfavorable outcomes with a sensitivity and specificity of 74.6% and 85.2%,respectively(P<0.001).The prognostic performance of ISI(area under the curve [AUC]=0.887) was similar to that of other predictors,such as gray-to-white matter ratio(AUC=0.850,P=0.433) and neuronspecific enolase(AUC=0.925,P=0.394).CONCLUSION:ISI may be used as a prognostic biomarker to predict neurological outcomes in CA patients following ECPR.

Hemodynamic Profiling Using a Cardiac Index–Systemic Vascular Resistance Plot in Patients with Fontan Circulation

Background: Elevated Fontan pressure (FP) alone cannot fully predict clinical outcomes. We hypothesized thathemodynamic profiling using a cardiac index (CI)-systemic vascular resistance (SVR) plot could characterize clinicalfeatures and predict the prognosis of post-Fontan patients. Methods: We included post-Fontan patients whounderwent cardiac catheterization at age < 10 years. Patients were classified into four categories: A, CI ≥ 3, SVRindex (SVRI) ≥ 20;B, CI < 3, SVRI ≥ 20;C, CI ≥ 3, SVRI < 20;and D, CI < 3, SVRI < 20. The primary outcome wasfreedom from the combined endpoint: new onset of protein-losing enteropathy or plastic bronchitis, heart transplant,and death. Clinical and hemodynamic variables and freedom from the endpoint were compared betweenthe hemodynamic categories and outcome predictors were evaluated. Results: Eighty-three patients wereincluded. Median follow-up was 5.3 years. Category A/B/C/D consisted of 4/15/53/11 patients, respectively. Allthe patients in category A were New York Heart Association I/II and had a significantly lower pulmonary vascularresistance index (PVRI). Patients in category C had lower pulmonary/systemic blood flow. Patients in category Dhad a higher PVRI and had the poorest freedom from the endpoint (44% at 5 years). Elevated FP and category Dwere outcome predictors. Conclusions: CI-SVR plots was a novel adjunctive method for Fontan hemodynamicprofiling.

Cardiac index (CI) versus cardio ankle vascular index (CAVI) at different degrees of head-up tilt (HUT) in healthy subjects

The cardio-ankle vascular index (CAVI) is a new index of arterial stiffness that can be measured with a VaSera VS-1000 device. An association between certain arterial stiffness indices and cardiac function has been found but has not yet been validated. The aim of this study was to establish whether any significant relationship exists between cardiac index (CI) and CAVI. Twenty healthy male volunteers with a mean age of 30 ± 5 years and a mean BMI of 23.1 ± 1.1 kg/m2 participated in the study. CO was estimated using a Doppler technique, and CAVI was measured with a VaSeraVS-1000 device. A motorised tilting table was used to achieve head-up tilt (HUT) angles of 0°, 30°and 60°, to modify the peripheral sympathetic outflow. We found that there was a significant inverse correlation between CI and the degree of head-up tilt, ( for 0°and 30°;for 0° and 60°, p for both;for 30° and 60°, ). CAVI showed a significant positive correlation relative with the degree of HUT, ( for 0° and 30°;for 0° and 60°;for 30° and 60°, for all). A significant negative correlation was found between CI and CAVI r = - 0.47, p Additionally, a significant p increase in PVR values was observed for increasing HUT values. In conclusion: An inverse relationship between CI and CAVI was shown;a decrease in cardiac output is associated with an increase in CAVI values at different degrees of HUT. This association provides further insight into the postural link between cardiac output and arterial compliance.

Application and Nursing of Pulse Index Continuous Cardiac Output (PiCCO) Volume Monitoring in Early Fluid Resuscitation in Patients with Septic Shock

Background: Septic shock is a rapidly changing and fatal syndrome that can cause comprehensive deterioration of cardiopulmonary and renal function and multiple organ failure. At the same time, septic shock has the complex clinical manifestations and hemodynamics. PiCCO can accurately monitor blood flow, physical and volume indicators, and active and effective fluid resuscitation are important measures to reduce the fatality rate of septic shock and improve the prognosis of patients. Objectives: To explore the application and nursing of PiCCO in early fluid resuscitation in patients with septic shock. Methods: This was a retrospective observational study. The observation group and the control group each had 30 cases. The observation group used PiCCO to guide fluid resuscitation;the control group used conventional methods to guide fluid resuscitation. The changes in CVP, HR, MAP, and urine volume per hour were observed in the two groups. The changes of various indicators before and after fluid resuscitation, the length of stay in ICU and the mortality rate were compared between the two groups. All the outcomes were collected from the electronic medical case system after patients’ discharge from the hospital. Results: APACHE II, CVP, HR, MAP were compared between the observation group and the control group, and the differences were statistically significant (P < 0.05). The blood volume of patients in the observation group was significantly improved after fluid supplementation (P < 0.05). Compared with the control group, the length of stay in ICU in the observation group was significantly shorter, and the mortality rate was also significantly reduced (P < 0.05). Conclusion: PiCCO can be better used in early fluid resuscitation of patients with septic shock.

Correlation between ultrasound Tei index and cardiac injury in cancer patients after thoracic radiotherapy

Objective: To study the correlation between ultrasound Tei index and cardiac injury in cancer patients after thoracic radiotherapy. Methods: The 78 patients with malignant tumor who received thoracic radiotherapy in Mianyang Central Hospital, Sichuan, China between February 2015 and March 2018 were selected as observation group, and 60 healthy volunteers who underwent physical examination during the same period were selected as control group. The observation group underwent cardiac ultrasonography before and after radiotherapy to calculate Tei indexes and serum was collected to determine cardiac injury markers, inflammatory cytokines and oxidative stress mediators, while the control group underwent cardiac ultrasonography during the physical examination to calculate Tei indexes and serum was collected to determine cardiac injury markers, inflammatory cytokines and oxidative stress mediators.Results: Left cardiac Tei index, right cardiac Tei index as well as serum creatine phosphokinase, creatine phosphokinase isoenzyme, troponin I, interferon-induced protein-10, interleukin-6, interleukin-10, transforming growth factor-β1 and 8-hydroxy-2-deoxyguanosine contents of the observation group after radiotherapy were significantly higher than those before radiotherapy and those of the control group (P<0.05), while serum total antioxidant capacity, superoxide dismutase and glutathione peroxidase contents were significantly lower than those before radiotherapy and those of the control group (P<0.05);Tei indexes were positively correlated with serum creatine phosphokinase, creatine phosphokinase isoenzyme, troponin I, interferon-induced protein-10, interleukin-6, interleukin-10, transforming growth factor-β1 and 8-hydroxy-2-deoxyguanosine contents, and negatively correlated with serum total antioxidant capacity, superoxide dismutase and glutathione peroxidase contents. Conclusions:Ultrasound Tei index is valuable in evaluating the cardiac injury in cancer patients after thoracic radiotherapy.

Application of pulse index continuous cardiac output system in elderly patients with acute myocardial infarction complicated by cardiogenic shock: A prospective randomized study

BACKGROUND Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS. AIM To assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by CS.METHODS Patients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals. RESULTS Sixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and 72 h. CONCLUSION Applying the PiCCO system could improve the clinical outcomes of elderly patients with AMI complicated by CS.

Noninvasive Assessment of Cardiac Index with Transesophageal Echocardiography in Patients Undergoing Mitral Valve Replacement: A Comparison between Determinations at the Mitral Valve and the Ascending Aorta

Methods: Sixteen patients with American Society of Anesthesiologists status (ASA) II-III, age ≤ 70 yr, male or female, preoperatively NYHA II-III and EF ≥ 45%, scheduled for mitral valve replacement (MVR) were studied. Complete intravenous general anesthesia was used for induction and anesthesia maintenance. After anesthesia induction we put the TEE probe into the esophagus. The cardiac index was determined at three periods following MVR: T1 30 minutes later following cessation of bypass, T2 60 minutes after cessation of bypass, T3 90 minutes after cessation of bypass. Statistical analysis was made with the Bland and Altman method. Results: Ninety-six measurements were compared. The cardiac index values at the level of prosthesis mitral valve (CIMV) ranged from 1.3 to 5.5 L·min-1·m-2 (mean 2.6 ± 0.9). The Values of cardiac index at aortic valve (CIAA) ranged from 2.7 to8.8 L·min-1·m-2 (mean 4.9 ± 1.7). Bias was -2.3 L·min-1·m-2 and limits of agreement -5.6 to 1.0 L·min-1·m-2. Conclusion: During mitral valve replacement, doubtful correlations were observed between values of cardiac index at the mitral valve and the ascending aorta using TEE.

血管内超声在心绞痛合并慢性肾功能不全PCI中的应用

目的:探究血管内超声在心绞痛合并慢性肾功能不全经皮冠状动脉介入治疗(PCI)中的应用。方法:选取2019年6月-2022年6月惠州市中心人民医院收治的200例心绞痛合并慢性肾功能不全患者为研究对象。根据随机抽签法将其分为对照组和观察组,各100例。两组均给予PCI,对照组在PCI中应用造影剂,观察组在PCI中应用血管内超声。比较两组围手术期指标,术前、术后96 h肾功能指标、心功能指标,心血管复合事件。结果:两组手术时间、支架置入数量比较,差异无统计学意义(P>0.05);观察组造影剂用量少于对照组,差异有统计学意义(P<0.05)。术后96 h,两组肾小球滤过率(GFR)、血肌酐(Scr)、血尿素氮(BUN)、24 h尿蛋白比较,差异无统计学意义(P>0.05)。术后96 h,观察组左室舒张末期内径(LVEDD)、左室收缩末期容积(LVESV)均低于对照组,左心室射血分数(LVEF)高于对照组,差异有统计学意义(P<0.05)。观察组心血管复合事件发生率低于对照组,差异有统计学意义(P<0.05)。结论:心绞痛合并慢性肾功能不全患者PCI中应用血管内超声,可减少造影剂用量,改善心功能,减少心血管复合事件。

Nitroglycerin reduces augmentation index and central blood pressure independent of effects on cardiac preload

Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compared effects of NTG with those of lower body negative pressure (LBNP). Hemodynamic measurements were made at rest,during LBNP (10,20 and 30 mmHg,each for 15 min) and after NTG (10,30 and 100 μg/min,each dose for 15 min) in ten healthy volunteers. Cardiac pre-load,stroke volume and cardiac output were assessed by echocardiography. Central pressure augmentation and central systolic pressure were obtained by radial tonometry using a transfer function. Results LBNP (20 mmHg) and NTG (30 μg/min) reduced pre-load (as measured by the peak velocity of the S wave in the superior vena cava) to a similar degree [by (26.8±3.8)% and (23.9±3.4)%,respectively]. Compared to LBNP,NTG reduced systemic vascular resistance [by (32.9±7.5)%,P<0.01],decreased peripheral and central pressure augmentation [by (20.8±3.4)% units and (12.9±2.9)% units,respectively,each P<0.01]. Conclusion These results suggest that a reduction in pre-load does not explain reduction in pressure augmentation and central systolic blood pressure by NTG and that these effects are mediated through arterial dilation.

超声心动图参数对择期PCI治疗冠心病患者预后的预测价值分析

目的探讨超声心动图参数对择期经皮冠状动脉介入术(PCI)治疗冠心病患者预后的预测价值。方法选取60例择期PCI治疗的冠心病患者作为观察组,另选取60例健康体检者作为对照组。两组均行超声心动图检查,比较两组超声心动图参数,观察组治疗前后超声心动图参数,不同预后患者的超声心动图参数。结果观察组左心室舒张末期容积(102.32±20.15)ml、左心室收缩末期容积(48.24±8.12)ml、左心室收缩末期容积指数(38.16±7.44)ml/m^(2)、左心室舒张末期容积指数(83.56±14.18)ml/m^(2)均高于对照组的(91.72±18.56)ml、(43.12±7.68)ml、(34.12±6.45)ml/m^(2)、(75.78±12.24)ml/m^(2),左心室射血分数(51.78±10.15)%、心输出量(5.13±0.42)L/min及心脏指数(2.92±0.46)L/(min·m^(2))均低于对照组的(57.16±8.42)%、(5.41±0.44)L/min、(3.21±0.54)L/(min·m^(2)),差异有统计学意义(P<0.05)。治疗后,观察组左心室舒张末期容积(94.78±19.15)ml、左心室收缩末期容积(45.18±7.32)ml、左心室收缩末期容积指数(35.52±6.72)ml/m^(2)、左心室舒张末期容积指数(78.56±12.27)ml/m^(2)均低于治疗前的(102.32±20.15)ml、(48.24±8.12)ml、(38.16±7.44)ml/m^(2)、(83.56±14.18)ml/m^(2),左心室射血分数(55.32±8.68)%、心输出量(5.30±0.48)L/min及心脏指数(3.10±0.52)L/(min·m^(2))均高于治疗前的(51.78±10.15)%、(5.13±0.42)L/min、(2.92±0.46)L/(min·m^(2)),差异有统计学意义(P<0.05)。观察组患者术后发生不良事件(预后不良组)20例,未发生不良事件(预后良好组)40例;预后不良组发生9例再梗死、7例心律失常和4例心力衰竭。预后不良组左心室舒张末期容积(101.18±20.32)ml、左心室收缩末期容积(47.14±8.32)ml、左心室收缩末期容积指数(36.56±7.12)ml/m^(2)、左心室舒张末期容积指数(82.52±13.48)ml/m^(2)高于预后良好组的(91.78±14.15)ml、(43.18±6.48)ml、(32.82±6.54)ml/m^(2)、(74.56±14.57)ml/m^(2),左心室射血分数(52.28±9.75)%、心输出量(5.16±0.45)L/min及心脏指数(2.94±0.44)L/(min·m^(2))低于预后良好组的(58.12±10.68)%、(5.40±0.42)L/min、(3.18±0.42)L/(min·m^(2)),差异有统计学意义(P<0.05)。结论超声心动图参数可监测择期PCI治疗冠心病患者的病情变化,也可对患者预后情况予以评估,可为疾病治疗工作的开展进行指导。

运用5G通信技术远程程控心脏置入型电子设备的有效性及安全性评价

目的:探讨与技术服务人员术中现场程控、测试心脏置入型电子设备(cardiac implantable electrical devices,CIEDs)各项参数的常规方式相比,该非接触式远程程控系统在CIEDs置入过程中的的安全性和有效性。方法:本研究为回顾性研究。依照时间顺序,连续分析了自2020年8月至2021年3月,于我院接受CIEDs置入的110例患者,根据术中程控及测试方式,分为常规程控组及非接触组。入选患者中,59例常规组患者由技术服务人员术中现场程控,其余51例非接触组患者通过新型远程非接触系统程控。结果:常规组的开关门频率高于非接触组[(9.8±1.8)vs.(5.8±1.2),P<0.05]。在CIEDs置入期间和术后12个月时,常规组和非接触组之间的设备相关参数差异及手术相关不良事件差异无统计学意义。结论:基于5G通信传输技术的新型非接触性程控系统与传统的程控方法相比,是安全有效的。

PCI治疗慢性心力衰竭合并冠心病的效果与预后情况刍议

目的 探究慢性心力衰竭合并冠心病患者应用经皮冠状动脉介入术(percutaneous coronary intervention,PCI)治疗的效果以及对患者预后的效果。方法 随机选择2020年3月—2022年3月期间北京王府中西医结合医院心内科收治的90例慢性心力衰竭合并冠心病患者为研究对象,采用随机法进行分组,参照组(45例)提供药物保守治疗,研究组(45例)提供经皮冠状动脉介入术(PCI)治疗,将两组患者的临床治疗效果进行比较。结果 在治疗总有效率方面,研究组(95.56%)高于参照组(77.78%),差异有统计学意义(χ^(2)=6.153,P=0.013)。研究组左室射血分数(LVEF)、左室短轴缩短率(FS)大于参照组,研究组左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)小于参照组,差异有统计学意义(P<0.05)。研究组血清N末端脑钠肽前体(NT-proBNP)、血清肌钙蛋白I(cTnI)小于参照组,差异有统计学意义(P<0.05)。研究组6 min步行距离(6MWD)大于参照组,美国纽约心脏学会心功能分级(NYHA)小于参照组,差异有统计学意义(P<0.05)。结论慢性心力衰竭合并冠心病患者接受PCI治疗可以提高治疗效果,改善预后。

慢性心力衰竭病人血清miR-487b表达水平及其与心肌重构的关系

目的:分析慢性心力衰竭病人血清微小核糖核酸-487b(miR-487b)表达水平及其与心肌重构的关系。方法:选取2019年10月—2021年10月西安高新医院收治的96例慢性心力衰竭病人作为研究组,按照纽约心脏病协会心功能分级将病人分为Ⅰ级或Ⅱ级22例,Ⅲ级41例,Ⅳ级33例;另选取同期在同一所医院体检的健康者102名作为对照组。采用实时荧光定量聚合酶链式反应(qRT-PCR)法检测所有研究对象血清miR-487b表达水平。比较研究组与对照组血清miR-487b表达水平及研究组不同心功能分级病人血清miR-487b表达水平。采用Pearson法分析慢性心力衰竭病人血清miR-487b表达水平与心肌重构指标[包括左室重构指数(LVRI)、左室舒张末期内径(LVEDD)、左心房内径(LAD)、左室质量指数(LVMI)、左室后壁厚度(LVPW)]的关系。结果:研究组血清miR-487b表达水平低于对照组(P<0.001);研究组LVEDD、LAD、LVMI、LVPW均高于对照组(P<0.001),LVRI低于对照组(P<0.001)。研究组心功能Ⅳ级病人LVEDD、LAD、LVMI、LVPW均高于Ⅰ级或Ⅱ级、Ⅲ级病人(P<0.05),miR-487b表达水平、LVRI均低于Ⅰ级或Ⅱ级、Ⅲ级病人(P<0.05);Ⅲ级病人LVEDD、LAD、LVMI、LVPW均高于Ⅰ级或Ⅱ级病人(P<0.05),miR-487b表达水平、LVRI均低于Ⅰ级或Ⅱ级病人(P<0.05)。Pearson相关分析结果显示,慢性心力衰竭病人血清miR-487b与LAD、LVMI、LVPW均呈负相关(r值分别为-0.578、-0.502、-0.514,P<0.001),与LVRI呈正相关(r=0.464,P<0.001)。结论:慢性心力衰竭病人血清miR-487b表达水平降低,且与心肌重构密切相关。

心脏彩色超声联合心踝血管指数和踝臂指数用于冠心病早期诊断的价值研究

目的:研究心脏彩色超声联合心踝血管指数(CAVI)和踝臂指数(ABI)用于冠心病早期诊断的价值。方法:选取2019年12月至2022年12月乐山市人民医院收治的146例冠心病患者,将其纳入观察组,另将同期在医院体检的70名正常体检者纳入健康对照组。两组受试者均行心脏彩色超声并检测CAVI、ABI,比较两组心肌做功指数(Tei指数)、舒张期E峰血流速度(E)与舒张晚期A峰血流速度(A)比值(E/A)、左心房内径(LAD)、左心室射血分数(LVEF)、CAVI以及ABI水平;绘制受试者工作特征(ROC)曲线,分析Tei指数、E/A、LAD、LVEF、CAVI及ABI单独诊断冠心病的价值;以冠状动脉造影结果为“金标准”,以一致性Kappa检验分析Tei指数、E/A、LAD、LVEF、CAVI及ABI联合诊断冠心病的效能。结果:观察组Tei指数、LVEF及CAVI水平明显高于健康对照组,差异有统计学意义(t=19.357、25.728、21.766,P<0.05),E/A、LAD及ABI水平明显低于健康对照组,差异有统计学意义(t=7.721、2.769、10.610,P<0.05)。经ROC分析证实Tei指数、E/A、LAD、LVEF、CAVI及ABI能够用于诊断冠心病,ROC曲线下面积分别为0.914、0.796、0.553、0.950、0.930和0.834。经一致性Kappa检验分析,Tei指数、E/A、LAD、LVEF、CAVI及ABI联合诊断冠心病的灵敏度为98.6%,特异度为92.9%,准确率为96.8%(Kappa=0.925,P<0.05)。结论:Tei指数、E/A、LAD、LVEF、CAVI及ABI可用于诊断冠心病,且联合诊断的效能更高。

参附注射液对急性心衰患者炎性指标、心功能及临床疗效的影响

目的观察参附注射液对急性心力衰竭(心肾阳虚型)患者的疗效,并探讨其作用机制。方法89例患者按随机数字表法分为观察组45例与对照组44例,两组均给予常规西药治疗,观察组在对照组基础上加用参附注射液。比较两组血清炎性指标、血流动力学指标、心功能及临床疗效。结果两组治疗前白细胞介素-6(IL-6)、超敏C反应蛋白(hs-CRP)、左心室射血分数(LVEF)、脑利钠肽(BNP)、肌酸激酶同工酶(CK-MB)、肌钙蛋白T(cTnT)水平和血流动力学指标心排血量(CO)、平均动脉压(MAP)、肺动脉压(PAP)水平比较,差异无统计学意义(均P>0.05)。两组治疗后5、10 d,IL-6、hs-CRP、LVEF、BNP、CK-MB、cTnT水平和血流动力学指标CO、MAP、PAP水平均较治疗前改善(均P<0.05),且观察组的各项指标改善均优于对照组(P<0.05)。治疗后观察组的总有效率为86.67%,高于对照组的72.73%。两组治疗期间及治疗后均未发现不良反应。结论参附注射液治疗急性心力衰竭可有效降低患者的血清炎性指标,改善血流动力学,提高心功能,改善生活质量,疗效良好。

超声新技术在评估胎儿心功能中的研究进展

超声心动图检查是目前评估胎儿心功能的主要方法之一。胎儿心脏定量分析技术(fetal heart quantify,Fetal HQ)、心肌做功指数(myocardial performance index,MPI)等超声心动图新技术可以较准确、客观地评估胎儿心功能。本文就Fetal HQ、MPI评估胎儿心功能的研究进展进行综述。

基于CI指数的淮河流域干旱时空特征研究

本文运用淮河流域170个气象台站1961—2010年共50年逐日气温、降水资料以及历史干旱灾情资料,研究CI指数在淮河流域的区域适应性,并以此为基础运用多种统计方法分析淮河流域近50年的干旱时空特征。结果表明:基于CI指数计算得到的历年干旱日数与受灾面积和成灾面积的相关性通过了0.01的显著性水平检验,表明CI指数在淮河流域具有较好的区域适应性。淮河流域年均干旱日数基本呈纬向空间分布,流域北部多于南部;流域东部和西部的干旱日数略有增多趋势,而中部和北部的干旱日数有减少趋势,但均未通过0.05的显著性水平检验;EOF前3个模态累积方差贡献达94.4%,前3个分布型依次为全流域干旱日数一致多或少型、南北相反型以及东西相反型;1961年以来干旱日数共经历了由少到多4个循环交替,目前正处于相对偏少期;M-K突变检验表明近50年来淮河流域干旱日数没有明显的突变。

基于CI指数的陕西干旱时空变化特征分析

利用1961—2010年陕西省72个气象站逐日气温和降水资料,采用综合气象干旱指数法,统计分析了近50年陕西省气象干旱发生的时空分布特征。结果表明:陕西省年及四季干旱发生频次和干旱日数总体上呈北高(多)南低(少)分布特征。四季中夏旱频率最高,强度最强,春季其次。各等级干旱日数中轻旱日数最多,中、重和特旱日数依次减少。陕北北部长城沿线及关中中东部既是干旱高发区,也是干旱重发区;近50年陕西区域干旱强度和干旱日数均存在较明显的增加趋势,主要表现为春秋两个季节的变化,而夏季和冬季的变化趋势不明显;近50年陕西共发生32起持续性干旱事件,以春夏连旱为主;20世纪90年代中后期至2002年持续性干旱事件发生的频率高,强度强,反映出陕西区域极端干旱事件对全球气候变化有明显的响应。

改进的综合气象干旱指数CI_(new)及其适用性分析

针对综合气象干旱指数CI的"不合理旱情加剧"问题,采用线性递减权重方法计算近90d降水和可能蒸散,提出改进的综合气象干旱指数CInew,并从干旱过程描述能力、干旱频率及旱期相对少雨季节滞后特征方面,通过与CI相比较阐述CInew的适用性特征。结果表明,(1)CInew在无降水时段平稳下降,有效克服了CI的"不合理旱情加剧"问题,能够描述干旱发生、发展和结束过程的丰富细节;(2)CInew的干旱频率与CI相比没有统计意义上的差异,但由于新的相对湿润度指数项MI90new统计时段由原来的30d延长至90d,使CInew能够刻画干旱频发开始月份(11月)相对于少雨时段开始月份(10月)的滞后效应。本文可为CInew在国内其它地方推广应用提供参考。

基于综合气象干旱指数(CI)的干旱时空动态格局分析——以甘肃省黄土高原区为例

借助ArcGIS 9.3和SPSS数据软件平台,根据甘肃省黄土高原区33个气象站1962-2010实测气象资料,利用综合气象干旱指数(CI)对甘肃省黄土高原区近50年的干旱特征进行了时空分析。首先计算了各站历年逐日的CI指数,统计近50年各站点出现的干旱过程、各时段的干旱事件,在此基础上分析了甘肃省黄土高原区历年各地区干旱发生的覆盖范围、频率和不同等级干旱发生的多年平均天数,揭示了甘肃省黄土高原区干旱发生的时空差异和动态格局。分析结果表明,(1)甘肃省黄土高原区有大范围干旱发生的年份,夏季和秋季较多分别有13、8 a,冬季最少,只有3 a。(2)从空间尺度来看,甘肃省黄土高原区中兰州-榆中-靖远一带和庆阳北部属于高值区,而岷县、渭源一带属于低值区;106°E以西"临洮-通渭-天水"一带和庆阳东南部是干旱变幅最大的地方。(3)从季节尺度来看,夏季干旱频率和持续日数最多,春季、秋季次之,冬季最少。