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find Keyword "pressure" 249 results
  • THE INVESTIGATION OF PAPILLEDEMA AND WIDTH OF OPTIC NERVE IN HIGH INTRACRANIAL PRESSURE

    The diameters of the optic nerves in 54 patients with high intracranial pressure(ICP)were checked and measured with B type ultrasonic tomography and the relationship between thewidth of optic nerve and the optic papiliedema was studied. The results showed that the average diameter (6. 324-0.53)mm of the optic nerves in patients with high ICP was wider than that(3.61 ~:0.29 )mm in health subjects (P(0.01). The rate of increasing width of optic nerve (87.00%)was higher than that (67.00~)of papilledema (P(0.05). In addition,in 19 patients with ICP between 1.97 and 2.50 kPa, the rate of increasing width of optic nerve (79. 00~)was higher than that (42.00%)of papilledema (P (0. 05). These results indicated that measuring the diameter of optic nerve might be more practical than observing tile presence of papilledema in diagnosing high ICP,especially in early stage. (Chin J Ocul Fundus Dis,1996,12: 86-87)

    Release date:2016-09-02 06:21 Export PDF Favorites Scan
  • Risk factors associated with failure of noninvasive positive pressure ventilation in acute respiratory failure due to acute exacerbation of chronic obstructive pulmonary disease

    Objective To analyze the risk factors of treatment failure by noninvasive positive pressure ventilation (NPPV) in patients with acute respiratory failure (ARF) due to acute exacerbation of chronic obstructive pulmonary disease (AECOPD), and explore the best time that NPPV be replaced by invasive ventilation when NPPV failure occurs. Methods The data of patients with ARF due to AECOPD who were treated with NPPV from January 2013 to December 2015 were retrospectively collected. The patients were divided into two groups: the NPPV success group and the NPPV failure group (individuals who required endotracheal intubation or tracheotomy at any time). The Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score was analyzed; the Glasgow Coma Scale score, respiratory rate (RR), pH value, partial pressure of oxygen (PaO2), PaO2/fraction of inspired oxygen (FiO2) ratio, and partial pressure of carbon dioxide were also analyzed at admission, after 2 hours of NPPV, and after 24 hours of NPPV. Results A total of 185 patients with ARF due to AECOPD were included. NPPV failed in 35.1% of the patients (65/185). Multivariate analysis identified the following factors to be independently associated with NPPV failure: APACHEⅡscore≥30 [odds ratio (OR)=20.603, 95% confidence interval (CI) (5.309, 80.525), P<0.001], RR at admission≥35 per minute [OR=3.723, 95%CI (1.197, 11.037), P=0.020], pH value after 2 hours of NPPV<7.25 [OR=2.517, 95%CI (0.905, 7.028), P=0.070], PaO2 after 2 hours of NPPV<60 mm Hg (1 mm Hg=0.133 kPa) [OR=3.915, 95%CI (1.374, 11.508), P=0.010], and PaO2/FiO2 after 2 hours of NPPV<200 mm Hg [OR=4.024, 95%CI (1.542, 11.004), P=0.010]. Conclusion When patients with ARF due to AECOPD have a higher severity score, have a rapid RR at admission, or fail to improve in terms of pH and oxygenation after 2 hours of NPPV, the risk of NPPV failure is higher.

    Release date:2017-11-24 10:58 Export PDF Favorites Scan
  • Design and simulation study of positive pressure ventilation system in a simulated human biological lung

    Simulation of the human biological lung is a crucial method for medical professionals to learn and practice the use of new pulmonary interventional diagnostic and therapeutic devices. The study on ventilation effects of the simulation under positive pressure ventilation mode provide valuable guidance for clinical ventilation treatment. This study focused on establishing an electrical simulation ventilation model, which aims to address the complexities in parameter configuration and slow display of air pressure and airflow waveforms in simulating the human biological lung under positive pressure ventilation mode. A simulated ventilation experiment was conducted under pressure-regulated volume control (PRVC) positive pressure ventilation mode, and the resulting ventilation waveform was compared with that of normal adults. The experimental findings indicated that the average error of the main reference index moisture value was 9.8% under PRVC positive pressure ventilation mode, effectively simulating the ventilatory effect observed in normal adults. So the established electrical simulation ventilation model is feasible, and provides a foundation for further research on the simulation of human biological lung positive pressure ventilation experimental platform.

    Release date:2024-10-22 02:33 Export PDF Favorites Scan
  • Application progress of venous pressure monitoring in arteriovenous fistula

    Venous pressure monitoring is an important indicator for the arteriovenous fistula evaluation. Direct static venous pressure monitoring is recognized as the most accurate way of venous pressure monitoring, which is widely used in the functional monitoring, functional evaluation of arteriovenous fistula, the diagnosis of complications and the evaluation of surgical efficacy. Venous pressure monitoring has obvious advantages and disadvantages, so it is necessary to improve relevant knowledge to correctly guide clinical diagnosis and treatment. In this paper, the study of static venous pressure monitoring of arteriovenous fistula was summarized, in order to improve the understanding of the significance and clinical application of static venous pressure monitoring of arteriovenous fistula.

    Release date:2022-08-24 01:25 Export PDF Favorites Scan
  • Safety and Efficacy of Intermittent Pneumatic Compression in The Treatment of Deep Venous Thrombosis

    ObjectiveTo investigate the safety and efficacy of intermittent pneumatic compression (IPC) in the treatment of deep venous thrombosis (DVT). MethodsThe clinical data of 496 patients with DVT who were treated in our hospital from January 2010 to October 2014 were analyzed retrospectively, to compare the time of venous pressure decreased to normal (T1) and time of circumference difference decreased to normal (T2) in patients received pure therapy (control group) and pure therapy combined with IPC (combination group), according to different types of patients in acute, sub-acute, and chronic phase. In addition, comparison of the remission rate of pulmonary embolism (PE), incidence of PE, and recurrence of DVT was performed between the control group and combination group too. Results① For DVT patients in acute stage, the time of T1 and T2 of patients in central type, peripheral type, and mixed type who received anticoagulant therapy/systemic thrombolysis/catheter thrombolysis+IPC, were significantly shorter than those patients who received only anticoagulant therapy/systemic thrombolysis/catheter thrombolysis (P<0.05). For DVT patients in sub-acute stage, the time of T1 and T2 of patients in central type and mixed type who received anticoagulant therapy/systemic thrombolysis+IPC, were significantly shorter than those of patients who received only anticoagulant therapy/systemic thrombolysis (P<0.05), the time of T1 of patients in peripheral type who received anticoagulant therapy/systemic thrombolysis+IPC, were significantly shorter than those of patients who received only anticoagulant therapy/systemic thrombolysis (P<0.01), but the time of T2 of patients in peripheral type didn't differed between patients who received only anticoagulant therapy/systemic thrombolysis and anticoagulant therapy/systemic thrombolysis +IPC (P>0.05). For DVT patients in chronic stage, the time of T1 and T2 of patients in central type and mixed type didn't differed between patients who received only anticoagulant therapy and anticoagulant therapy +IPC (P>0.05); the time of T1 of patients in peripheral type who received anticoagulant therapy+IPC, were significantly shorter than those of patients who received only anticoagulant therapy (P<0.05), but the time of T2 didn't differed with each other (P>0.05). ② There were 63 patients in control group and 47 patients in combination group had PE before treatment. After the treatment, the PE symptom of control group relieved in 56 patients (88.89%, 56/63) and maintained in 7 patients (11.11%, 7/63), the symptom of combination group relieved in 44 patients (93.62%, 44/47) and maintained in 3 patients (6.38%, 3/47), so the remission rate of PE symptom in combination group was higher (P<0.05). There were 6 patients suffered from new PE in control group[4.26% (6/141)] and 0 in combination group[0 (0/245)] after treatment in patients who hadn't PE before treatment, and the incidence of PE was lower in combination group (P<0.05). ③ There were 325 patients were followed up for 3-36 months with the median time of 27 months, including 157 patents in control group and 168 patients in combination group. During the follow-up period, 74 patients recurred[47.13% (74/157)] in control group and 46 patients recurred[27.38% (46/168)] in combination group, and the recurrence rate was lower in combination group (P<0.05). In addition, 41 patients suffered from post-thrombotic syndrome[26.11% (41/157)] in control group and 27 patients[16.07% (27/168)] in combination group, and the incidence of post-thrombotic syndrome was lower in combination group (P<0.05). ConclusionsIPC can significantly shorten the time of venous pressure and the circumference difference decreased to normal for DVT patients in acute stage and majority DVT patients in sub-acute stage, and it can relieve the clinical symptoms of PE, reduce the incidence rate of PE and recurrence rate of DVT. Therefore, IPC is a safe, reliable, and effective treatment for DVT patients in acute stage and majority DVT patients in sub-acute stage.

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  • The Role of Maintaining Constant Pressure of the Endotracheal Catheter Cuff in Prevention of Ventilator-associated Pneumonia

    ObjectiveTo explore the preventive role of maintaining constant pressure of the endotracheal catheter cuff on ventilator-associated pneumonia (VAP). MethodsFrom January to December 2015, 96 patients of type Ⅱ respiratory failure were selected as the trial group who underwent intubation and mechanical ventilation more than 48 hours in the Intensive Care Unit (ICU). We used pressure gauges to measure the endotracheal catheter cuff pressure regularly and maintained a constant pressure in addition to the application of artificial airway cluster management. We recorded the initial pressure value which was estimated by pinching with finger and set initial pressure to 30 cm H2O (1 cm H2O=0.098 kPa). We measured endotracheal catheter cuff pressure and recorded it during different intervals. We reviewed 88 patients with the same disease as the control group who only accepted artificial airway cluster management between January and December 2014. Mechanical ventilation time, VAP occurrence time, ICU admission time, the incidence of VAP were recorded and analyzed for both the two groups of patients. ResultsIn the trial group, the initial pressure of endotracheal catheter cuff which was estimated by pinching with finger showed that only 11.46% of pressure was between 25 and 30 cm H2O and 82.29% of the pressure was higher than 30 cm H2O. We collected endotracheal catheter cuff pressure values during different interval time by using pressure gauges to maintain a constant management. The ratio at the pressure between 25 and 30 cm H2O was respectively 41.32%, 43.75%, 64.20%, 76.54%, 91.13%, and 91.85%. ICU admission time, mechanical ventilation time in patients of the trial group decreased more, compared with the control group, and the differences were statistically significant (t=4.171, P<0.001; t=4.061, P<0.001). The VAP occurrence time in patients of the trial group was later than the control group (t=2.247, P<0.001). ConclusionThe endotracheal catheter cuff pressure estimated by pinching with finger has errors. We recommend using pressure gauges to detect pressure every four hours, which utilizes minimal time to maintain effective pressure. The method of artificial airway of cluster management combined with the pattern of maintaining constant endotracheal catheter cuff pressure can shorten ICU admission time, mechanical ventilation time and delay the occurrence of VAP.

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  • Characteristics of Coronary Artery in Patients with Hypertension and Coronary Heart Disease

    Objective To investigate the characteristics of blood pressure and coronary artery impairment in patients with essential hypertension (EH) combining coronary heart disease (CHD). Methods A total of 358 patients with EH combining CHD and other 144 patients with CHD were measured with ambulatory blood pressure monitoring (ABPM), and the parameters of ambulatory blood pressure were analyzed. All the patients underwent coronary angiography. The severity of coronary artery stenosis was evaluated in accordance with the number of impaired arteries. Results Compared to the patients with simplex CHD, those with EH combining CHD had much heavier artery stenosis and more diffuse lesions, with significant differences (χ2=6.03, P=0.019). The 24h systolic blood pressure (SBP), day SBP, night SBP, 24h pulse pressure (PP), day PP and night PP were higher in the patients with EH combining CHD compared to those of the patients with simplex CHD (The t values were 2.580, 2.045, 2.675, 2.037, 2.601, and 1.995, respectively, while the P values were 0.015, 0.037, 0.009, 0.041, 0.017, and 0.047, respectively). Conclusion Compared to the patients with simplex CHD, the patients with EH combining CHD suffer from much severe coronary artery impairment, so a good controlling of blood pressure is advisable to improve the coronary artery impairment for the patients with EH combining CHD.

    Release date:2016-09-07 11:06 Export PDF Favorites Scan
  • Development of Physiologic Fixation Method on Porcine Aortic Root and Aortic Valve Leaflets

    Objective To study the development of a physiologic fixation method and investigate the effect of physiologic fixation method on porcine aortic root and aortic valve leaflets. Methods Physiological fixer of aortic root was manufactured in a factory. The fixers with different diameter were made of organic glass. Porcine aortic root with ascending aorta and anterior leaflet of mitral valve and partial ventricular septum were dissected out from the fresh heart. The roots were attached to appropriately sized inflow and outflow spigots. Physiologic fixation was utilized to maintain aortic root and leaflets natural anatomical shape, the aortic root was pressurized to the inflow and outflow portions simultaneously, and the leaflets floated freely at zero-pressure differential with in the pressurized root. Results The process of physiologic fixation retained the properties of a native valve. The leaflets were much softer and extensible than those from valves fixed under low pressure. The results of pulsatile flow testing indicated that the effective orifice areas of predilation at 80mmHg were significantly greater than those of predilation at 40 mmHg(P〈0.05), while mean pressure differences were found to be lower comparatively(P〈0.05). This difference translates into a mode of valve function that more closely approximates that of the native aortic valve. Conclusion Physiologic fixation process retains the valve's natural anatomical shape as well as the underlying structure of the leaflets, providing improved flow characteristics.

    Release date:2016-08-30 06:23 Export PDF Favorites Scan
  • Assessment and Curative Effect of Percutem Transilluminated with Negative Pressured on The Potaried Technique on Treatment of Venous Ulcer in Lower Extremity

    Objective To assess the curative effect of percutem transilluminated with negative pressured on the potaried technique on the treatment of venous ulcer in lower extremity. Methods The clinical date of 300 cases involving 300 legs with venous ulcer in lower extremity, who underwent the percutum transilluminated negative pressured potaried technique using TRIVEXTM Ⅱ potaried system or the percutum transfixion surgical treatment from October 2005 to June 2009, were analyzed. Three hundred cases were randomly divided into potaried group and transfixion group. In potaried group, there were 190 cases involving 190 legs treated with TRIVEXTM Ⅱ potaried system. In transfixion group, 110 cases involving 110 legs treated with percutum transfixion. The clinical indexes of skin infection rate and skin necrosis rate, shrinkage rate of wound area and skin depigmentation rate, ulcer healing rate and ulcer recurrence rate were calculated to assess the clinical curative effect on day 5, day 20, day 120 and day 360 after operation respectively. Results The rates of skin infection and skin necrosis were significantly decreased in potaried group compared with transfixion group on day 5 after operation (P<0.05), the rates of shrinkage of wound area and skin depigmentation were significantly increased in potaried group compared with transfixion group on day 20 (P<0.05). The ulcer healing rate was not significantly different between the two groups on day 120 (Pgt;0.05). Ulcer recurrence rate was remarkably lower in potaried group than that in transfixion group on day 360 (P<0.05). Conclusion It can be concluded that percutem transilluminated with negatived pressured on the potaried technique with TRIVEXTM Ⅱ potaried system can efficiently promote the healing of venous ulcer in the lower extremity, and at the same time it has an ascendancy in lessening skin infection and skin reinjury.

    Release date:2016-08-28 03:48 Export PDF Favorites Scan
  • Domestic artificial cervical disc interface pressure distribution and effect of bone-implant interface pressure on osseointegration

    Objective To analyze the distribution of stress in the upper and lower plates of the prosthesis-bone interface, and the effect of interface pressure on osseointegration. Methods CT scanning was performed on goats at 1 week after artificial cervical disc replacement to establish the finite element model of C3, 4. The stress distribution of the upper and lower plates of the interface was observed. At 6 and 12 months after replacement, Micro-CT scan and three dimensional reconstruction were performed to measure the bone volume fraction (BVF), trabecular number (Tb. N), trabecular thickness (Tb. Th), trabecular separation (Tb. Sp), bone mineral density (BMD), bone surface/bone volume (BS/BV), and trabecular pattern factor (Tb. Pf). The C3 lower plate and C4 upper plate of 4 normal goat were chosen to made the cylinder of the diameter of 2 mm. The gene expressions of receptor activator for nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), transforming growth factor β (TGF-β), and macrophage colony-stimulating factor (M-CSF) were detected by real time fluorescent quantitative PCR at immediate after cutting and at 24 and 48 hours after culture. The samples of appropriate culture time were selected to made mechanical loading, and the gene expressions of RANKL, OPG, M-CSF, and TGF-β were detected by real time fluorescent quantitative PCR; no mechanical loading samples were used as normal controls. Results Under 25 N axial loading, the stress of the upper plate of C3, 4 was concentrated to post median region, and the stress of the lower plate to middle-front region and two orbits. According to stress, the plate was divided into 5 regions. The Micro-CT scan showed that BMD, Tb.Th, BVF, and Tb.N significantly increased, and BS/BV, Tb.Sp, and Tb.Pf significantly decreased at 12 months after replacement when compared with ones at 6 months (P<0.05). At 24 and 48 hours after culture, the gene expressions of RANKL, OPG, and TGF-β were signifi-cantly higher than those at immediate (P<0.05), but no significant difference was found between at 24 and 48 hours after culture (P>0.05). The mechanical loading test results at 24 hours after culture showed that the RANKL and OPG gene expressions and OPG/RANKL ratio in C3 lower plate and C4 upper plate were significantly up-regulated when compared with controls (P<0.05), but no significant difference was shown in TGF-β and M-CSF gene expressions (P>0.05). Conclusion Domestic artificial cervical disc endplate has different pressure distribution, the stress of lower plate is higher than that of upper plate. Pressure has important effect on local osseointegration; the higher pressure area is, the osseointegration is better. Under the maximum pressure in interface, the osteoblast proliferation will increase, which is advantageous to the local osseointegration.

    Release date:2017-04-12 11:26 Export PDF Favorites Scan
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