Predictive value of Pv-aCO 2/Ca-vO 2 combined blood lactate concentration for primary peritonitis-related septic shock in children / 中华危重病急救医学

Objective:To investigate the prognostic value of the ratio of veno-arterial carbon dioxide partial pressure difference to arterio-venous oxygen content difference (Pv-aCO 2/Ca-vO 2) in children with primary peritonitis-related septic shock. Methods:A retrospective study was conducted. Sixty-three children with primary peritonitis-related septic shock admitted to department of intensive care unit of the Children's Hospital Affiliated to Xi'an Jiaotong University from December 2016 to December 2021 were enrolled. The 28-day all-cause mortality was the primary endpoint event. The children were divided into survival group and death group according to the prognosis. The baseline data, blood gas analysis, blood routine, coagulation, inflammatory status, critical score and other related clinical data of the two groups were statistics. The factors affecting the prognosis were analyzed by binary Logistic regression, and the predictability of risk factors were tested by the receiver operator characteristic curve (ROC curve). The risk factors were stratified according to the cut-off, Kaplan-Meier survival curve analysis compared the prognostic differences between the groups.Results:A total of 63 children were enrolled, including 30 males and 33 females, the average age (5.6±4.0) years old, 16 cases died in 28 days, with mortality was 25.4%. There were no significant differences in gender, age, body weight and pathogen distribution between the two groups. The proportion of mechanical ventilation, surgical intervention, vasoactive drug application, and procalcitonin, C-reactive protein, activated partial thromboplastin time, serum lactate (Lac), Pv-aCO 2/Ca-vO 2, pediatric sequential organ failure assessment, pediatric risk of mortality Ⅲ in the death group were higher than those in the survival group. Platelet count, fibrinogen, mean arterial pressure were lower than those in the survival group, and the differences were statistically significant. Binary Logistic regression analysis showed that Lac and Pv-aCO 2/Ca-vO 2 were independent risk factors affecting the prognosis of children [odds ratio ( OR) and 95% confidence interval (95% CI) were 2.01 (1.15-3.21), 2.37 (1.41-3.22), respectively, both P < 0.01]. ROC curve analysis showed that the area under curve (AUC) of Lac, Pv-aCO 2/Ca-vO 2 and their combination were 0.745, 0.876 and 0.923, the sensitivity were 75%, 85% and 88%, and the specificity were 71%, 87% and 91%, respectively. Risk factors were stratified according to cut-off, and Kaplan-Meier survival curve analysis showed that the 28-day cumulative probability of survival of Lac ≥ 4 mmol/L group was lower than that in Lac < 4 mmol/L group [64.29% (18/28) vs. 82.86% (29/35), P < 0.05]. Pv-aCO 2/Ca-vO 2 ≥ 1.6 group 28-day cumulative probability of survival was less than Pv-aCO 2/Ca-vO 2 < 1.6 group [62.07% (18/29) vs. 85.29% (29/34), P < 0.01]. After a hierarchical combination of the two sets of indicator variables, the 28-day cumulative probability of survival of Pv-aCO 2/Ca-vO 2 ≥ 1.6 and Lac ≥ 4 mmol/L group significantly lower than that of the other three groups (Log-rank test, χ2 = 7.910, P = 0.017). Conclusion:Pv-aCO 2/Ca-vO 2 combined with Lac has a good predictive value for the prognosis of children with peritonitis-related septic shock.

Predictive value of Pcv-aCO 2 on left ventricular ejection fraction in myocardial infarction / 中华急诊医学杂志

Objective:To investigate the relationship between central venous-arterial blood carbon dioxide partial pressure difference (Pcv-aCO 2) and left ventricular ejection fraction(LVEF) in acute myocardial infarction. Methods:Clinical data of patients with acute myocardial infarction admitted to the Intensive Care Unit of Fujian Provincial Hospital from November 2019 to October 2021 were retrospectively analyzed. LVEF was measured by bedside echocardiogram. The patients were divided into the normal LVEF group (LVEF ≥ 52%) and decreased LVEF group (LVEF < 52%) according to LVEF. The differences in general information and hemodynamic parameters between the two groups were compared. The normality of the above data was tested by the Jarque-Bera test. Correlation analysis of hemodynamic indices with LVEF was performed. Binary logistic regression was used to analyze the risk factors associated with the decrease in LVEF. The feasibility of diagnosing LVEF decline with Pcv-aCO 2 was assessed using receiver operating characteristic (ROC) curve. Results:Seventy-two patients with acute myocardial infarction were included for analysis, including 25 patients in the normal LVEF group and 47 patients in the decreased LVEF group. Pcv-aCO 2 was significantly higher in the decreased LVEF group than that in the normal LVEF group [(7.13±1.19) mmHg vs. (5.41±1.23) mmHg, P<0.01]. There was a negative correlation between LVEF and Pcv-aCO 2 ( rs= -0.740, P<0.01). The area under the ROC curve for Pcv-aCO 2 was 0.849 (95% CI: 0.758-0.939, P<0.01). The binary logistic regression analysis showed that Pcv-aCO 2 was an independent risk factor for decreased LVEF ( OR=2.251, 95% CI: 1.326-3.820). Conclusions:To a certain extent, the increase of Pcv-aCO 2 can predict the decrease of LVEF in acute myocardial infarction.

Experimental Study on Effects of Mitral Regurgitation on Hydrodynamic Performance of Aortic Valve / 中国医疗器械杂志

OBJECTIVE@#Aims researches on the interaction between heart valves is limited in clinical. Meanwhile the data of in vitro testing are insufficient. In this study, the in vitro hydrodynamic performance of an aortic valve was studied by using a model of mitral regurgitation that could finely adjust the regurgitant volume.@*METHODS@#The regurgitation of mitral valve was gradually increased under the certain condition of heart rate, stroke volume, and mean aortic pressure and captured the hydrodynamic performance of the aortic valve.@*RESULTS@#The study on the hydrodynamic performance of mechanical aortic valve (25AJ-501) by using a model of mitral regurgitation found that the effective orifice area and mean pressure difference of the aortic valve are negatively correlated with the degree of mitral regurgitation.@*CONCLUSIONS@#The method based on a model of mitral regurgitation that could finely adjust the regurgitant volume established in this study can be used to study the effect of mitral valve regurgitation on the hydrodynamic performance of the aortic valve.

Factors affecting the elevation of inter-arm systolic blood pressure difference in a physical examination population / 中华健康管理学杂志

Objective:To analyze the related factors affecting the inter-arm systolic blood pressure difference (IASBPD) in a physical examination population.Methods:A total of 3 600 adults who underwent physical examination and completed the arteriosclerosis test in the first affiliated hospital of Anhui medical university from January 2019 to June 2021 were selected as the participants by systematic sampling method. Data on age, sex, and history of smoking, heavy drinking, hypertension, type 2 diabetes, and coronary heart disease were recorded. The height, weight, waist circumference, hip circumference, total muscle, total fat and body fat ratio were measured, and body mass index was calculated. The blood pressure of the limbs, ankle brachial index (ABI) were measured synchronously with the arteriosclerosis tester of the Chinese Academy of Sciences, and the IASBPD were calculated. According to the IASBPD value, the participants were divided into two groups: IASBPD<10 mmHg (1 mmHg=0.133 kPa) group and IASBPD≥10 mmHg group, The differences between the two groups were compared, and the related influencing factors of IASBPD were analyzed by multivariate logistic regression.Results:Weight, body mass index, waist circumference, hip circumference, systolic blood pressure, diastolic blood pressure, total muscle, total fat, body fat rate, history of hypertension, proportion of type 2 diabetes mellitus, and proportion of history of coronary heart disease in the IASBPD≥10 mmHg group was higher than that of IASBPD<10 mmHg group [(69.1±11.2) vs (65.3±10.8) kg, (25.6±3.4) vs (24.4±3.3) kg/m 2, (91.3±11.3) vs (87.8±10.6) cm, (98.5±10.4) vs (96.5±9.8) cm, (139.7±20.0) vs (129.7±17.6) mmHg, (80.3±11.6) vs (76.7±10.1) mmHg, (47.5±9.1) vs (45.3±8.8) kg, (19.4±7.0) vs (17.6±6.4) kg, (27.9%±8.5%) vs (26.8%±8.1%), 41.1% vs 29.3%, 16.6% vs 11.7%, 13.1% vs 7.3%] (all P<0.05); ABI was lower than that in IASBPD<10 mmHg group [(1.15±0.11) vs (1.20±0.09)] ( P<0.001). There were no significant differences in height, smoking history and heavy drinking history between the two groups (all P>0.05). Multivariate logistic regression analysis showed that age, systolic blood pressure, body weight and ABI were independent influencing factors of IASBPD≥10 mmHg. Age, systolic blood pressure and body weight were positively correlated with IASBPD≥10 mmHg, while ABI was negatively correlated with IASBPD≥10 mmHg. Conclusion:Increases in age, systolic blood pressure, and body weight and a decrease in ABI are important influencing factors leading to the elevation of IASBPD.

Experimental study on the relationship between foam pressure difference and foam stability / 生物医学工程学杂志

Foam stability affects the efficacy and incidence of side effects of foam sclerotherapy. Exploring the relationship between foam pressure difference and foam stability can provide ideas and basis for obtaining more stable foam. In the experiment, sodium cod liver oleate foam was selected, and poloxamer 188 (concentration of 0%, 4%, 8%, 12%) was added to realize the change of foam pressure. By using the self-written program to process the foam pictures, the foam pressure difference and the relationship between the foam stability indicators (water separation rate curve, half-life) and the foam pressure difference were obtained. The results showed that at first the foam pressure increased with the increase of the concentration, and then it decreased with the increase of the concentration and reached a peak at the concentration of 4%. The foam pressure difference decreases continuously with the increase of decay time. When the additive concentration is low, the foam average pressure difference increases. And if the additive concentration is too high, the foam average pressure difference decreases. The smaller the foam pressure difference is, the better the foam stability is. This paper lays a foundation for the research on the stability of foam hardener.

Evaluation of diastolic left ventricular relative pressure in patients with type 2 diabetes mellitus by vector flow mapping / 中华超声影像学杂志

Objective:To evaluate the distribution of diastolic left ventricular pressure in patients with type 2 diabetes mellitus (T2DM) by relative pressure imaging (RPI) based on vector flow mapping (VFM), and to explore the clinical risk factors for the diastolic left ventricular pressure distribution.Methods:Thirty patients with T2DM and thirty normal controls were included from August 2020 to July 2021 in Fuwai Central China Cardiovascular Hospital. All selected subjects underwent conventional echocardiography.Left intraventricular pressure difference (IVPD) and left intraventricular pressure gradient (IVPG) were measured using RPI of VFM in isovolumic relaxation (IR), rapid filling (RF), atrial contraction (AC), isovolumic contraction (IC) and rapid ejection (RE) phases. The relationships between IVPD with other parameters were analyzed.Results:①Compared with the control group, E/A, e′, IVPD-IR, IVPG-IR, IVPD-RF, IVPG-RF, IVPD-AC, and IVPG-AC were significantly lower and E/e′ was significantly greater in the T2DM group ( P<0.05). ②IVPD-IR, IVPD-RF, and IVPD-AC were positively correlated with E/A ( r=0.309, P<0.05; r=0.274, P<0.05; r=0.273, P<0.05). IVPD-IR, IVPD-RF, and IVPD-AC were negatively correlated with E/e′ ( r=-0.587, P<0.05; r=-0.273, P<0.05; r=-0.415, P<0.05). IVPD-IR and IVPD-AC were positively correlated with e′ ( r=0.451, P<0.05; r=0.431, P<0.05). ③Multivariable linear regression analysis showed that hemoglobin A 1c (HbA 1c) was an independent risk factor affecting IVPD-IR, IVPD-RF, and IVPD-AC (β=-0.417, P<0.05; β=-0.451, P<0.05; β=-0.460, P<0.05). Conclusions:RPI of VFM can quantitatively evaluate diastolic left ventricular pressure distribution in patients with T2DM. HbA 1c is an independent risk factor affecting IVPD-IR, IVPD-RF, and IVPD-AC.

The preliminary value of vector flow mapping on assessment of left intraventricular pressure difference in patients with paroxysmal atrial fibrillation / 生物医学工程学杂志

This study aims to explore the intraventricular pressure difference (IVPD) within left ventricle in patients with paroxysmal atrial fibrillation (PAF) by using the relative pressure imaging (RPI) of vector flow mapping (VFM). Twenty patients with paroxysmal atrial fibrillation (PAF) and thirty control subjects were enrolled in the study. Systolic and diastolic IVPD derived from VFM within left ventricle and conventional echocardiographic parameters were analyzed. It was found that the B-A IVPD of left ventricle in PAF patients showed the same pattern as controls-single peak and single valley during systole and double peaks and double valleys during diastole. Basal IVPD was the main component of base to apex IVPD (B-A IVPD). The isovolumetric systolic IVPD was associated with early systolic IVPD, early systolic IVPD was associated with late systolic IVPD, and late systolic IVPD was associated with isovolumic diastolic IVPD (all

Prevalence and related factors of abnormal four-limb blood pressure difference in elderly people in Shanghai / 上海交通大学学报（医学版）

Objective • To investigate the prevalence and related factors of abnormal four-limb blood pressure difference in elderly people in Shanghai. Methods • From 2016 to 2018, the elderly aged 60 years and over in Zhaoxiang Town, Qingpu District, Shanghai were selected by cluster sampling. General data was collected. Height, body mass, and blood pressure were measured. Fasting venous blood was taken for routine blood test, blood glucose, blood lipids, serum creatinine and other biochemical indicators. Four limb blood pressures were measured simultaneously by Vascular Profiler-1000 device, from which ankle-brachial index, inter-arm systolic pressure difference and inter-ankle systolic pressure difference were calculated. Multivariate Logistic regression was used to analyze the related factors of abnormal four-limb blood pressure difference. Results • A total of 4 090 subjects were enrolled with an average age of (68.5±7.6) years, of which 44.6% were males. The people with hypertension and diabetes mellitus accounted for 60.1% and 8.6%, respectively. The prevalence of ankle-brachial index≤ 0.90, inter-arm systolic pressure difference≥ 15 mmHg (1 mmHg=0.133 kPa) and inter-ankle systolic pressure difference≥ 15 mmHg were 2.7%, 1.9%, and 8.4%, respectively. After incorporating age, sex, body mass index (BMI), smoking, drinking, hypertension, diabetes mellitus, total cholesterol and triacylglycerol, the results of multiple Logistic regression analysis showed that age and hypertension were the related factors of the three indicators for abnormal four-limb blood pressure difference. The related factors of ankle-brachial index ≤ 0.90 also included diabetes mellitus, total cholesterol and smoking; the related factors of inter-arm systolic pressure difference≥ 15 mmHg also included BMI; the related factors of inter-ankle systolic pressure difference≥ 15 mmHg also included BMI and diabetes mellitus. Conclusion • Abnormal four-limb blood pressure difference is prevalent among the elderly in Shanghai, of which old age, hypertension, diabetes, dyslipidemia, obesity and smoking are risk factors.

Assessment of hemodynamic parameters distribution in normal carotid artery by using computational fluid dynamics based on CE-MRA data / Avaliação da distribuição dos parâmetros hemodinâmicos na artéria carótida normal utilizando a dinâmica de fluidos computacional baseada em dados CE-MRA

This study was to analyze the in vivo distribution of wall shear stress (WSS), velocity and inplane pressure difference in normal carotid artery by using computational fluid dynamics (CFD) based on contrastenhanced MRA (CE-MRA) data and to determine whether there were differences in these hemodynamic parameters between atherosclerosis-free and atherosclerosis-prone areas. CE-MRA was performed on 16 normal carotid arteries to obtain carotid three-dimensional surface data. CFD analysis was then performed to estimate those parameters in atherosclerosis-free (distal common carotid artery and distal internal carotid artery) and atherosclerosis-prone (carotid bifurcation) areas. One-way analysis of variance (ANOVA) was conducted to analyze differences among these three areas. CFD analysis revealed that WSS and velocity were significantly lower in carotid bifurcation compared to distal common carotid artery (CCA) (P =0.011, P <0.001, respectively) and distal internal carotid artery (ICA) (P <0.001, P <0.001, respectively). While in-plane pressure difference was significantly higher in carotid bifurcation compared to distal CCA (P <0.001) and distal ICA (P =0.005). Hemodynamic environment in carotid bifurcation of normal carotid artery which assessed by using CFD analysis appeared to be with lower WSS and lower velocity, while with higher in-plane pressure difference. These characterizations might facilitate the initiation of atherosclerosis.

Este estudo teve como objetivo analisar a distribuição in vivo da tensão de cisalhamento da parede (WSS), velocidade e plano diferença de pressão na artéria carótida normal usando dinâmica de fluidos computacional (CFD) baseada em contraste Dados do MRA (CE-MRA) e para determinar se houve diferenças nesses parâmetros hemodinâmicos entre áreas livres de aterosclerose e propensas à aterosclerose. O CE-MRA foi realizado em 16 artérias carótidas normais para obter dados de superfície tridimensional da carótida. A análise CFD foi então realizada para estimar esses parâmetros em livre de aterosclerose (artéria carótida comum distal e artéria carótida interna distal) e propensa a aterosclerose (carótida bifurcação). Análise de variância unidirecional (ANOVA) foi realizada para analisar as diferenças entre essas três áreas. A análise de CFD revelou que o WSS e a velocidade foram significativamente menores na bifurcação carotídea em comparação com a comum distal artéria carótida (ACC) (P = 0,011, P <0,001, respectivamente) e artéria carótida interna distal (ACI) (P <0,001, P <0,001, respectivamente). Enquanto a diferença de pressão no plano foi significativamente maior na bifurcação carotídea em comparação com a CCA distal (P <0,001) e ICA distal (P = 0,005). Ambiente hemodinâmico na bifurcação carotídea da artéria carótida normal que avaliada por meio de análise de CFD parece estar com menor WSS e menor velocidade, enquanto com maior pressão no plano diferença. Essas caracterizações podem facilitar o início da aterosclerose.

Predictive value of central venous-to-arterial carbon dioxide partial pressure difference for fluid responsiveness in septic shock patients: a prospective clinical study / 中华危重病急救医学

Objective To evaluate the accuracy of central venous-to-arterial carbon dioxide partial pressure difference (Pcv-aCO2) before and after rapid rehydration test (fluid challenge) in predicting the fluid responsiveness in patients with septic shock. Methods A prospective observation was conducted. Forty septic shock patients admitted to medical intensive care unit (ICU) of Peking Union Medical College Hospital from October 2015 to June 2017 were enrolled. All of the patients received fluid challenge in the presence of invasive hemodynamic monitoring. Heart rate (HR), blood pressure, cardiac index (CI), Pcv-aCO2 and other physiological variables were recorded at 10 minutes before and immediately after fluid challenge. Fluid responsiveness was defined as an increase in CI greater than 10% after fluid challenge, whereas fluid non-responsiveness was defined as no increase or increase in CI less than 10%. The correlation between Pcv-aCO2 and CI was explored by Pearson correlation analysis. Receiver operating characteristic (ROC) curves were established to evaluate the discriminatory abilities of baseline and the changes after fluid challenge in Pcv-aCO2 and other physiological variables to define the fluid responsiveness. The patients were separated into two groups according to the initial value of Pcv-aCO2. The cut-off value of 6 mmHg (1 mmHg = 0.133 kPa) was chosen according to previous studies. The discriminatory abilities of baseline and the change in Pcv-aCO2(ΔPcv-aCO2) were assessed in each group. Results A total of 40 patients were finally included in this study. Twenty-two patients responded to the fluid challenge (responders). Eighteen patients were fluid non-responders. There was no significant difference in baseline physiological variable between the two groups. Fluid challenge could increase CI and blood pressure significantly, decrease HR notably and had no effect on Pcv-aCO2 in fluid responders. In non-responders, blood pressure was increased significantly and CI, HR, Pcv-aCO2 showed no change after fluid challenge. Pcv-aCO2 was comparable in responders and non-responders. In 40 patients, CI and Pcv-aCO2 was inversely correlated before fluid challenge (r = -0.391, P = 0.012) and the correlation between them weakened after fluid challenge (r = -0.301, P = 0.059). There was no significant correlation between the changes in CI and Pcv-aCO2 after fluid challenge (r = -0.164, P = 0.312). The baseline Pcv-aCO2 and ΔPcv-aCO2 could not discriminate between responders and non-responders, with the area under ROC curve (AUC) of 0.50 [95% confidence interval (95%CI) =0.32-0.69] and 0.51 (95%CI = 0.33-0.70), respectively. HR and blood pressure before fluid challenge and their changes after fluid challenge showed very poor discriminative performances. Before fluid challenge, 16 patients had a Pcv-aCO2 > 6 mmHg. Their mean CI was significantly lower and Pcv-aCO2 was significantly higher than that in 24 patients whose Pcv-aCO2 ≤6 mmHg [n = 24; CI (mL·s-1·m-2): 48.3±11.7 vs. 65.0±18.3, P < 0.01; Pcv-aCO2 (mmHg): 8.4±1.9 vs. 2.9±2.8, P < 0.01]. Pcv-aCO2was decreased significantly after fluid challenge in patients with an initial Pcv-aCO2 > 6 mmHg and their ΔPcv-aCO2 was notably different as compared with the patients whose baseline Pcv-aCO2≤6 mmHg (mmHg: -3.8±3.4 vs. 0.9±2.9, P < 0.01). 68.8% (11/16) patients responded to the fluid challenge in patients with an initial Pcv-aCO2 > 6 mmHg. The AUC of the baseline Pcv-aCO2 and ΔPcv-aCO2 to define fluid responsiveness was 0.85 (95%CI = 0.66-1.00) and 0.84 (95%CI = 0.63-1.00), respectively, and the positive predictive value was 1 when the cut-off value was 8.0 mmHg and -4.2 mmHg, respectively. 45.8% (11/24) patients responded to the fluid challenge in patients whose baseline Pcv-aCO2≤6 mmHg. There was no predictive value of baseline Pcv-aCO2 and ΔPcv-aCO2 on fluid responsiveness. Conclusion Pcv-aCO2 and its change cannot serve as a surrogate of the change in cardiac output to define the response to fluid challenge in septic shock patients whose baseline Pcv-aCO2≤6 mmHg, while the predictive values of baseline Pcv-aCO2and the change in Pcv-aCO2 are presented in patients with the initial value of Pcv-aCO2 > 6 mmHg. Clinical Trial Registration Clinical Trials, NCT01941472.

Experimental study on the in vivo continuous measurement of pressure difference between the anterior and the posterior chambers / 生物医学工程学杂志

A set of device for the measurement of the pressure difference between the anterior and the posterior chambers (PDAP) was designed to investigate the temporal varying rules of PDAP in the anterior segment of rabbit eyes. A platform was established for the measurement of PDPA according to the mechanism of joint implement. Rabbit models with high intraocular pressure (IOP) were constructed by means of injecting Carbomer into anterior chamber to increase IOP. The 24 hours continuous measurements of PDAP were performed for normal rabbit eye and eye with high IOP. The developed device could sensitively response to the small pressure difference in eye. The pressure difference in the normal rabbit eye varied with time, and the variation range during a whole day was 5.84-96.84 Pa which reflected the existence of physiological rule. For the rabbit eye with high IOP, pressure in anterior chamber was higher than that in posterior chamber which was in consistence with the theory of self-adaptation adjustment. The present study indicates that the approaches and device designed in this paper can well implement the measurement of PDAP as well as the temporal varying rules of PDAP in the anterior segment during a whole day.

Cerebrospinal Fluid Pressure and Trans-lamina Cribrosa Pressure Difference in Open-angle Glaucoma: KNHANES V

PURPOSE: To investigate the relationships between estimated cerebrospinal fluid pressure (CSFP) and trans-lamina cribrosa pressure difference (TLCPD) in open-angle glaucoma (OAG) in Korean population. METHODS: A total of 10,801 eyes were included from the Korean National Health and Nutrition Examination Survey V. All participants (aged 19 years or older) were classified as non-glaucomatous group, OAG suspect group and OAG group. CSFP was calculated as CSFP (mm Hg) = 0.44 body mass index (kg/m²) + 0.16 diastolic blood pressure (mm Hg) - 0.18 age (years) - 1.91. TLCPD was calculated by subtracting CSFP from intraocular pressure. RESULTS: The mean estimated CSFP was (8.7 ± 3.3 mm Hg vs. 11.6 ± 3.7 mm Hg, 11.2 ± 3.8 mm Hg vs. 11.6 ± 3.7 mm Hg) was lower, and the mean TLCPD (5.7 ± 4.4 mm Hg vs. 2.2 ± 4.4 mm Hg, 3 ± 4.7 mm Hg vs. 2.2 ± 4.4 mm Hg) was higher in the OAG group and in the OAG suspect group than in the non-glaucomatous control group, respectively (p < 0.001). After adjusting relating factor with CSFP and TLCPD using simple linear regression and multivariate analyses, the mean estimated CSFP was distributed lower (p < 0.001; beta: -0.12; B: -2.306; 95% confidence interval [CI]: -2.717, -1.895) in OAG group than in non-glaucomatous group and the mean TLCPD was distributed higher (p < 0.001; beta: 0.099; B: 1.349; 95% CI: 0.977, 1.72; p < 0.001; beta: 0.118; B: 2.776; 95% CI: 2.264, 3.289) in OAG suspect group and in OAG group than in non-glaucomatous group, respectively. CONCLUSIONS: Estimated CSFP and calculated TLCPD showed essential association with OAG presence. It supports the potential role of low CSFP in the pathogenesis of OAG.

Correlation between Trans-lamina Cribrosa Pressure Difference and Morphologic Parameters of Optic Disc in Normal Tension Glaucoma Patients

PURPOSE: To investigate the relationship between trans-lamina cribrosa pressure difference (TLCPD) and morphologic parameters of optic disc (OD) in normal tension glaucoma (NTG) patients. METHODS: Data from 31 NTG patients (31 eyes) and 29 controls (29 eyes) were analyzed retrospectively. Their cerebrospinal fluid pressure was estimated using diastolic pressure (DBP), body mass index (BMI) and age. TLCPD was defined as the difference of intraocular pressure (IOP) and the estimated cerebrospinal fluid pressure (ECSFP). Measurements of the rim area (RA), disc area (DA), average and vertical cup/disc (C/D) ratio, retinal nerve fiber layer thickness (RNFLT) and cup volume (CV) were taken for all patients using optical coherence tomography. The correlation between TLCPD and morphologic parameters of OD were assessed. RESULTS: There were no significant differences between the two groups in terms of age, DBP, IOP and spherical equivalent (SE) and BMI. The mean ECSFP was significantly higher in the controls (10.7 ± 2.8 vs. 12.2 ± 2.2 mm Hg, p = 0.031) and TLCPD was significantly higher in patients (2.4 ± 2.1 vs. 4.9 ± 3.7 mm Hg, p = 0.002). In the NTG group, there was a negative correlation between TLCPD and RA (r = -0.595) and positive correlations between TLCPD and the average C/D ratio (r = 0.504), vertical C/D ratio (r = 0.434) and CV (r = 0.420). Average RNLFT was also significantly correlated with TLCPD (r = -0.500) and RNFLT for four quadrants, except the nasal quadrant, in NTG patients. CONCLUSIONS: NTG patients had higher TLCPD. A higher TLCPD was associated with a narrower RA, larger C/D ratio, and thinner RNFLT.

Therapeutic effect of nicorandil for treatment of patients with acute respiratory distress syndrome / 中国中西医结合急救杂志

Objective To investigate the clinical effect of nicorandil for treatment of patients with acute respiratory distress syndrome (ARDS).Methods A prospective randomized controlled trial was conducted. A total of 40 cases of patients with ARDS admitted to Department of Critical Care Medicine of Guizhou Provincial People's Hospital from October 2012 to October 2014 were enrolled, and they were randomly divided into two groups, 20 cases in each group. The two groups were treated with routine western medicine after admission. On this basis, the observation group was given nicorandil 10 mg, while the control group was given warm boiled water 10 mL, through gastric tubes 3 times a day, the therapeutic course being consecutive 5 days in both groups. The length of stay in intensive care unit (ICU), duration of mechanical ventilation after treatment, oxygenation index (OI), alveolo-arterial oxygen partial pressure difference (PA-aO2), positive end-expiratory pressure (PEEP), acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, Glasgow coma score (GCS) before and after treatment, the predicted death rate (PDR) and 28-day mortality were compared between the two groups. The predicitive factors for 28-day mortality were screened by binary logistic analysis.Results The length of stay in ICU and duration of mechanical ventilation of control group were longer than those of observation group, but the difference was not statistically significant [ICU length of stay (day): 14.55±12.71 vs. 9.15±6.00, duration of mechanical ventilation (day): 13.25±12.27 vs. 7.75±5.32, bothP > 0.05]. After treatment, the GCS was higher than that before treatment in control group and observation group (11.95±3.98 vs. 10.75±4.89, 12.95±3.67 vs. 12.20±4.56), while APACHE Ⅱ score, PDR and PEEP were all lower than those before treatment [APACHE Ⅱ: 21.05±8.58 vs. 24.90±5.63, 18.70±11.21 vs. 26.65±7.67; PDR: (47.71±29.49)% vs. (61.00±23.29)%, (36.79±18.49)% vs. (56.12±18.16)%; PEEP (cmH2O, 1 cmH2O = 0.098 kPa): 4.40±3.14 vs. 5.75±2.59, 3.80±2.55 vs. 7.55±3.32], but there were no statistically significant differences between the two groups before and after treatment (allP > 0.05). After treatment, the OI was significantly higher and the PA-aO2 was significantly lower than those before treatment in the two groups, and the degrees of improvement of the observation group were more remarkable than those of the control group [OI (mmHg, 1 mmHg = 0.133 kPa): 224.72±85.12 vs. 141.37±45.82, PA-aO2 (mmHg): 132.60±46.64 vs. 204.30±121.2, bothP 0.05). Binary logistic regression analyses showed that the PA-aO2 [odds ratio (OR) = 0.958,P = 0.013, 95% confidence interval (95%CI) = 0.927 - 0.991], APACHE Ⅱ score (OR = 0.882,P = 0.010, 95CI = 0.803 - 0.970), GCS (OR = 1.399, P = 0.004, 95%CI = 1.111 - 1.761) and PDR (OR = 0.907,P = 0.002, 95%CI = 0.853 - 0.965) after treatment were the independent predictors of 28-day mortality.Conclusion Nicorandil can significantly improve oxygenation, but cannot reduce 28-day mortality in patients with ARDS.

Relationship Between Coronary Artery Calcification and Pulse Pressure Difference in the Rural Population of Yunnan Province / 中国循环杂志

Objective: Based on coronary artery calciifcation (CAC) distribution in the rural population of Yunnan province, we further explored the relationship between coronary artery calciifcation score (CACS) and the pulse pressure difference (PPD). Methods: A randomly stratiifed cluster sampling method was used to study the rural population of Yunnan province and 16-MDCT scan was performed in 212 subjects for evaluating their CAC and calculating CACS. The subjects were divided into 2 sets of groups according to the age and CACS value. Age (51-60) years group,n=108 and Age (61-71) years group,n=104; CACS Results: The average PPD level in Age (61-71) years group was (44.67±13.87) mmHg and in Age (61-71) years group was (50.00±17.44) mmHg,P=0.015, PPD was positively related to age, rs=0.202,P=0.003. The average PPD level in CACS≥100 group, CACS Conclusion: PPD as a risk factor of coronary artery disease is related to CACS in rural population of Yunnan province, the CACS increased accordingly with the elevated PPD level.

Study on intracranial pressure, glaucoma and research advance in noninvasive measurements about intracranial pressure / 国际眼科杂志(Guoji Yanke Zazhi)

Glaucoma is the first leading cause of irreversible blindness and the second leading cause of blindness worldwide. Numerous studies have shown that elevated intraocular pressure ( IOP ) is one of the major risk factors for the development and progression of glaucomatous optic nerve damage. However, there have been 50% of primary open-angle glaucoma ( POAG ) patients with typical glaucomatous optic neuropathy in whom the IOP measurements have always been in the normal range, and some patients develop typical glaucomatous optic neuropathy with the well controlled IOP. These phenomena cannot be explained by the theory of high intraocular pressure. The pathogenesis of glaucomatous optic nerve damage in these patients with normal IOP needs to be further discussed. Numerous studies at home and abroad have shown that: 1. the surrounding anatomy of the optic nerve including the IOP, the anatomy and biomechanics of the lamina cribrosa and retrobulbar orbital cerebrospinal fluid pressure may be of importance for the pathogenesis of the POAG;2. patients with normal tension glaucoma had significantly lower cerebrospinal fluid pressure and a higher trans - lamina cribrosa pressure difference compared with normal subjects; 3. patients with ocular hypertension had significantly higher cerebrospinal fluid pressure, however, there is no difference in trans -lamina cribrosa pressure compared with normal subjects. Based on the above research, now we make a review about the research advance of the relation between intracranial pressure and glaucoma optic nerve damage and the available measurements about noninvasive intracranial pressure in clinical in this paper.

Medición de presiones relativas en aorta torácica y arteria pulmonar de voluntarios sanos y pacientes con Tetralogía de Fallot reparada utilizando la secuencia 4D Flow de resonancia magnética cardíaca / Relative pressure measurement in thoracic aorta and pulmonary artery in healthy volunteers and patients with Tetralogy of Fallot repaired by 4D Flow cardiovascular MRI

Objective. To validate the utility of 4D Blood Flow and Navier-Stokes equations to create relative pressure (RP) maps in the aorta and pulmonary artery (PA) in healthy volunteers and patients with repaired tetralogy of Fallot (TOF). Methods. A 4D flow sequence of whole heart and its major vessels was acquired in 10 healthy volunteers and 6 patients with repaired TOF. The root of the ascending aorta was used as the reference point to calculate RP along five different points of this area. In addition, relative pressure of both right and left PA was measured as correlated to absolute pressure. Results. Patients with repaired TOF showed greater pulmonary artery (PA) relative pressure differences between maximum and minimum values when compared to volunteers (p <0.05). Additionally, aortic relative pressures had an excellent correlation with published data, whether using 4D flow or by catheterization. Conclusions. 4D Flow MRI may represent a new non-invasive and non operator-dependent diagnostic tool in CV disease management.

Objetivo. Utilizar 4D Flow y las ecuaciones de Navier-Stokes para obtener mapas de presiones relativas (PR) en la Aorta y Arteria Pulmonar (AP) de voluntarios y pacientes con Tetralogía de Fallot reparada (TOFr). Métodos. En 10 voluntarios y 6 pacientes con TOFr se adquirió la secuencia 4D flow del corazón y sus principales vasos. La raíz de la Aorta Ascendente se utilizó como referencia para calcular las PR a esta zona en cinco puntos distintos. Además, se midió la PR de la AP derecha e izquierda respecto a la AP. Resultados. Los pacientes con TOFr tuvieron diferencias de PR entre los valores máximos y mínimos más grandes que los voluntarios en la AP (p<0,05). Adicionalmente, las PR de la aorta tuvieron una excelente correlación con datos publicados utilizando 4D flow y mediante cateterización. Conclusiones. 4D Flow podría constituir una nueva herramienta diagnóstica, no invasiva, ni operador dependiente, en el manejo de patologías CV.

Blood pressure measurement: One arm or both arm.

Guidelines for measuring blood pressure includes measurement of blood pressure on both arms but it is often ignored. Our case report aims at highlighting the need follow the guidelines. A 60 year old 59 kg weighing male asymptomatic patient without any comobidities was posted for bilateral inguinal hernia repair. The interarm blood pressure difference was discovered incidentally during his preanaesthetic evalution. On further evaluation patient was found to be having subclavian stenosis on left side which was asymptomatic. Intraoperative and post operative period was uneventful. Blood pressure measurement should be done in accordance with the stipulated guidelines. Inter arm blood pressure difference should be noted in all patients as not only for diagnosis and treatment of hypertension but also as a tool to diagnose asymptomatic peripheral vascular disesase.

Research on lumped parameter model based on intra-aorta pump / 医用生物力学

Objective Try to set up a nonlinear lumped parameter model of intra-aorta pump by studying the relationship between the pressure difference and the blood flow rate at the head of the pump, so as to predict the hemodynamic parameters of the pump. Methods Only the parameters of the pump, without hemodynamic parameters of the circulating system, were used to esfablish the model. It was composed of a speed-controlled current source representing the flow rate driven by impeller, an internal resistant representing the resistance of the radial clearance, an inductance denoting the inertance of the blood. Results The model could simulate the physiological status of the heart under all the situations from pulmonary congestion to ventricular collapse. The characteristic equation of the pump was derived with parameters determined by experimental data in vitro. Conclusions To verify the accuracy of the model, the prediction value calculated from the model was compared with the one recorded from experiment in vitro. The results showed that the error in between was less than 5%, which indicated that this model could predict the pressure difference of the pump accurately.

A Case of Successful Correction of Subclavian Steal Syndrome by Percutaneus Transluminal Angioplasty with Stenting Who Found Incidentally Significant Interarm Blood Pressure Difference / 가정의학회지

A case of successful correction of subclavian steal syndrome by percutaneous transluminal angioplasty with stenting in a male patient who found incidentally significant interarm blood pressure difference. Small difference in blood pressure (BP) between two arms is a relatively common. Significant interarm BP difference is a potential marker of peripheral vascular disease such as subclavian artery stenosis and a predictor of cardiovascular disease. The subclavian steal syndrome is a condition that results from stenosis of subclavian artery proximal to the vertebral artery. The resulting symptoms are vertebrobasilar insufficiency symptoms due to reversal of blood flow from the contralateral vertebral and basilar artery into the ipsilateral upper extremity vessels and arm ischemic symptoms. Stenotic lesion of subclavian artery has traditionally been treated surgically. However recent trends are undergoing a paradigm shift from open surgery to endovascular approach. We report a patient with subclavian steal syndrome who found incidentally 35 mmHg interarm systolic BP difference. It was successfully treated by percutaneus transradial angioplasty with stenting on stenotic lesion of the subclavian artery.