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find Keyword "diameter" 30 results
  • The risk factors of posttracheostomy tracheal stenosis and postintubation tracheal stenosis

    ObjectiveTo explore the risk factors for tracheal stenosis caused by tracheotomy or intubation.MethodsFrom July 2010 to July 2020, a total of 44 patients were suffered with tracheal stenosis caused by tracheotomy or intubation at the First Affiliated Hospital of Hunan Normal University as case group (n=44), and 34 patients were suffered tracheotomy or intubation without tracheal stenosis as control group (n=34). The clinical application of intratracheal tube cuff diameter was investigated by univariate comparison, ROC analysis and multivariate logistic regression analysis.ResultsUnivariate analysis showed intratracheal tube cuff diameter (C)/transverse diameter at the level of the clavicle >150%, intubation time>7d, tracheal intubations/tracheostomy ≥2, recurrent respiratory tract infections and replacement of tracheal tube≥ 2 were the influence factors of posttracheostomy tracheal stenosis (PTTS) and postintubation tracheal stenosis (PITS) (P<0.005). Multivariate Logistic regression analysis showed C/T>150% (OR=6.681, 95%CI: 1.164 - 38.363), intubation time>7d (OR=4.723, 95%CI: 1.413 - 15.779), tracheal intubations/tracheostomy ≥2 (OR=4.526, 95%CI: 1.133 - 18.083) and recurrent respiratory tract infections (OR=3.681, 95%CI: 1.177 - 11.513) were positively correlated with PTTS and PITS. The area under the ROC curve (AUC) of C/T>150% was 0.665 with the sensitivity of 0.364 and the specificity of 0.033 (95%CI: 0.555 - 0.775). AUC of intubation time>7 d was 0.717 with the sensitivity of 0.568 and the specificity of 0.133 (95%CI: 0.613 - 0.821). AUC of tracheal intubations/tracheostomy ≥2 was 0.683 with the sensitivity of 0.432 and the specificity of 0.067 (95%CI: 0.574 - 0.791). AUC of recurrent respiratory tract infections was 0.707 with the sensitivity of 0.614 and the specificity of 0.200 (95%CI: 0.603 - 0.811). However, there was no statistically significant difference C/T>150% and those clinical data in Z test (Z=0.839, P=0.402; Z=0.302, P=0.763; Z=0.751, P=0.453).ConclusionIntubation time>7 d, tracheal intubations/tracheostomy ≥2, recurrent respiratory tract infections, replacement of tracheal tube≥ 2 and C/T>150% are risk factors for PTTS and PITS.

    Release date:2021-06-30 03:37 Export PDF Favorites Scan
  • Relationship between Bicuspid Aortic Valve and Ascending Aortic Dilatation Assessed by Computed Tomography Angiography

    ObjectiveTo find the relationship between bicuspid aortic valve (BAV) and the dilatation or aneurysm of the aorta using electrocardiogram-gated computed tomography angiography (CTA). MethodsWe collected the clinical data of the BAV coexisting with suspected aortic dilatation or aneurysm from February 2012 through April 2015. A total of 124 patients were analyzed retrospectively. There were 97 males and 27 females at an anverage age of 50.35±16.26 years. According to the CTA, patients were classified into two groups: a pure BAV(without raphe) group and a BAV (with raphe) group. we recorded the aortic diameters, gender, age, and so on. ResultsOf the 124 patients, 91 (73.4%) had BAV with raphe, and 33 patients (26.6%) had pure BAV. The analysis revealed that the diameter of the annulus (23.90±3.34 mm vs. 21.74±3.46 mm, P=0.005), the sinuses of Valsalva (40.93±6.78 mm vs. 37.35±7.06 mm, P=0.022), the tubular portion of the ascending aorta (45.38±7.66 mm vs. 38.29±8.18 mm, P=0.0001), and the part of the aorta proximal to the innominate artery (34.19±4.98 mm vs. 30.23±6.62 mm, P=0.02) between patients with BAV with raphe and pure BAV had significant differences. And there was a significant difference in prevalence of dilatation of the aorta between patients with pure BAV and BAV with raphe [77/91 (84.6%) vs.18/31(58.1%), P=0.004]. Of the 91 BAV with raphe patients, we found 76 patients (83.5%) with right and left coronary cusps (R-L) fusion, 13 patients (14.3%) with right and non-coronary cusps (R-N) fusion, and 2 patients (1.2%) with left and non-coronary cusps (L-N) fusion. There was a statistical difference in the aortic root diameters between R-L fusion BAV and R-N fusion BAV. The diameter of the distal ascending aorta and proximal aortic arch between R-L and R-N fusion BAV had statistical differences. ConclusionsBAV with raphe is more common than pure BAV and is more often associated with dilatation and aneurysm of the ascending aorta. Otherwise R-L fusion BAV is associated with increased diameters of the aortic root, while R-N fusion BAV is associated with increased diameters of the distal ascending aorta and proximal arch.

    Release date:2016-11-04 06:36 Export PDF Favorites Scan
  • The Changes in Structure and Function of Left Ventricular in COPD Patients

    Objective To analyze the influence of COPD on the structure and function of left ventricular. Methods Sixty-nine COPD patients ( mean age: 69. 0 ±7. 8 yrs) and forty healthy controls ( mean age: 67. 8 ±7. 6 yrs) were enrolled in this study. Both groups underwent Doppler echocardiography.Heart rate ( HR) were recorded. Left ventricular end-diastolic volume ( LVEDV) , left ventricular enddiastolic diameter ( LVEDD) , interventricular septum( IVS) , stroke volume ( SV) , and cardiac output ( CO)were measured. The changes of left ventricular were compared between the COPD patients and the healthy controls, and also between the COPD patients with or without chronic cor pulmonale. Results Compared with the healthy controls, movement range of IVS, LVEDD, LVEDV, and SV reduced significantly ( P lt;0. 05) , and HR raised significantly in the COPD patients ( P lt; 0. 05) . CO had no significant difference between two groups ( P gt;0. 05) . Sub-group analysis indicated that the thickness and movement range of IVSwere greater in the patients with cor pulmonale secondary to COPD than those without cor pulmonale ( P lt;0. 05) . Conclusions In COPD patients, left ventricular chamber size decreases, and left ventricular systolic function is impaired. Left ventricular function is impaired more severe in cor pulmonale secondary to COPD than COPD without cor pulmonale.

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  • EFFECT OF PREPARATION CONDITIONS FOR SMALLDIAMETER ARTIFICIAL POLYURETHANE VASCULAR GRAFT ON MICROSTRUCTURE AND MECHANICAL PROPERTIES

    Objective To study the effect of preparation conditions for small-diameter polyurethane(PU) vascular graft on microstructure and mechanical properties. Methods The small-diameter microporous PU artificial vascular grafts were prepared by dipping and leaching method. The dimension and microstructure were controlled by changing mold diameter, PU materials, salt sizes, salt to polymer ratio, times of dipping layers etc. The mechanical properties of PU grafts including radical compliance, water permeability, longitudinal strength, burst strength, and suture tearing strength were measured and the effect of the graft dimension and microstructure on their properties were studied. Results The internal diameter of grafts prepared was 2-4 mm depending on mold diameter. The wall thickness was 0.6-1.2 mmafter dipping 4-8 layers. The density was 0.23-0.49 g/cm3. The pore was 42-95 μm in diameter. The porosity was 56%80%. The radical compliance was 1.2%-7.4%·13.3 kPa-1 and higher compliances could be obtained by using moreelastic polyurethane, higher salt to polymer ratio, longer diameter and less wall thickness. The water permeability, mainly depending on salt to polymer ratio,diameter, and wall thickness, was 0.29-12.44 g/(cm2·min). The longitudinal strength was 1.55-4.36 MPa correlating with tensile strength of polyurethane and salt to polymer ratio. The burst strength was 60-300 kPa also depending on tensile strength of polyurethane and salt to polymer ratio. The suture tearing strength was 19.5-96.2 N/cm2 depending on tensile strength of polyurethanebut not on the angle of tearing and graft axial directions. The compliance and water permeability of Chronoflex grafts were higher than those of PCU1500 grafts, but longitudinal strength, burst strength, and suture tearing strength of PCU1500 grafts were better than those of Chronoflex grafts. Conclusion Small-diameter grafts with proper pore sizes, porosity, matching compliance can be obtained by selecting PU materials and optimizing the preparation conditions.

    Release date:2016-09-01 09:27 Export PDF Favorites Scan
  • Risk factors for 24-hour death in acute type A aortic dissection patients with conservative treatment

    ObjectiveTo explore the risk factors for 24-hour death in acute type A aortic dissection (ATAAD) patients with conservative treatment.MethodsFrom January 2009 to January 2018, 243 ATAAD patients who received non-surgical intervention were admitted in Beijing Anzhen Hospital, including 167 males and 76 females with an average age of 53.0±12.0 years. The risk factors for 24-hour mortality were analyzed.ResultsThe total in-hospital mortality rate was 37.9% (93/243), and 13.6% (33/243) patients died within 24 hours of onset. We found that left ventricular end diastolic diameter [LVEDD, OR=0.45, 95%CI (0.25, 0.83), P<0.01] and aortic regurgitation [OR=7.26, 95%CI (1.67, 31.53), P<0.01] were independent risk factors for 24-hour death in patients with ATAAD.ConclusionIn this study, LVEDD and aortic regurgitation are identified as independent risk factors for 24-hour mortality in ATAAD patients. Therefore, patients with aortic regurgitation and small LVEDD should be treated with sugery as soon as possible.

    Release date:2021-07-28 10:22 Export PDF Favorites Scan
  • Effect of respiratory effort on inferior vena cava diameter variability

    Objective To analyze the quantitative relationship between respiratory effort and inferior vena cava (IVC) diameter variability in healthy adults, and explore the effects of respiratory effort on the fluid responsiveness with IVC diameter variability. Methods From October 2022 to May 2023, a cross-sectional study was conducted in healthy young subjects who met the criteria. Respiratory effort was evaluated by using portable pulmonary function to measure the subjects’ inspiratory conditions in three states (quiet breathing, moderate inspiration, and maximal inspiration). At the same time, the IVC internal diameter was measured by bedside ultrasound and the IVC diameter variability was calculated. The correlation between inspiratory volume and IVC diameter variation was analyzed, and the receiver operator characteristic (ROC) curve was drawn. The sensitivity and specificity of fluid responsiveness induced by inspiratory effort were predicted according to the area under the ROC curve (AUC). Results A total of 95 subjects were screened, aged 27.13±5.77 years, of whom 30 (32%) subjects were males. During quiet breathing, 41.1% of subjects had IVC inner diameter variation ≥50%. For moderate inspiration, it was 68.4%. At maximum inspiration, this proportion is more than 85%. Inspiratory volume was moderately positively correlated with IVC diameter variation, and the correlation coefficient r=0.45. With the IVC diameter variation ≥50% as the positive criterion for fluid responsiveness, the AUC of fluid responsiveness induced by inspiratory effort was 0.73 (95% confidence interval 0.67 - 0.78, P<0.001), and the inspiratory volume threshold was 13 mL/kg ideal body weight when the maximum Youden index was 0.41. That is, moderate force breathing can induce fluid responsiveness, with sensitivity of 79.57% and specificity of 61.62%. Conclusion The degree of respiratory effort significantly affects the IVC inner diameter variation, and there may be false positives in the evaluation of fluid responsiveness according to IVC inner diameter variation in the case of spontaneous breathing.

    Release date:2024-07-29 01:12 Export PDF Favorites Scan
  • Effect of sinus diameter on the opening and closing performance of aortic valve under the expansion of aortic root

    This study aims to explore the effect of aortic sinus diameter on aortic valve opening and closing performance in the case of no obvious disease of aortic valve and annulus and continuous dilation of aortic root. A total of 25 three-dimensional aortic root models with different aortic sinus and root diameters were constructed according to the size of clinical surgical guidance. The valve sinus diameter DS is set to 32, 36, 40, 44 and 48 mm, respectively, and the aortic root diameter DA is set to 26, 27, 28, 29 and 30 mm, respectively. Through the structural mechanics calculation with the finite element software, the maximum stress, valve orifice area, contact force and other parameters of the model are analyzed to evaluate the valve opening and closing performance under the dilated state. The study found that aortic valve stenosis occurs when the DS = 32 mm, DA = 26, 27 mm and DS = 36 mm, DA = 26 mm. Aortic regurgitation occurs when the DS = 32, 36 and 40 mm, DA = 30 mm and DS = 44, 48 mm, DA = 29, 30 mm. The other 15 models had normal valve movement. The results showed that the size of the aortic sinus affected the opening and closing performance of the aortic valve. The smaller sinus diameter adapted with the larger root diameter and the larger sinus diameter adapted with the smaller root diameter. When the sinus diameter is 40 mm, the mechanical performance of the valve are good and it can well adapt with the relatively large range of aortic root dilation.

    Release date:2019-12-17 10:44 Export PDF Favorites Scan
  • Assessment of the internal mammary artery using ultrasound in patients with coronary artery disease before coronary artery bypass grafting

    ObjectiveTo investigate the feasibility and effectiveness of using ultrasound to evaluate the internal mammary artery (IMA) and explore the related factors affecting the quality of IMA.MethodsFrom July 2020 to January 2021, for patients who underwent coronary artery bypass grafting at the Department of Cardiovascular Surgery, Fuwai Hospital, ultrasound was applied to measure bilateral IMA at the parasternal second intercostal space. There were 62 males and 18 females with an average age of 59.9±8.3 years. The clinical data of the patients were recorded and analyzed.ResultsA total of 160 IMA were measured. The IMA was detected in 99.4% (159/160), and the one that was not measured was proved to be occluded by enhanced CT. A total of 157 (98.1%) IMA intima were smooth, 2 (1.3%) were found to have uneven intimal thickening and less smooth, and only 1 (0.6%) was occluded. The intravascular diameter, peak systolic flow rate, peak diastolic flow rate, and blood flow rate of the left second intercostal IMA were 1.9±0.3 mm, 66.8±17.7 cm/s, 6.4 (0.0, 9.7) cm/s, 19.7±9.4 mL/min; and those of the right one were 2.1±0.3 mm, 69.7±18.5 cm/s, 6.0 (0.0, 9.2) cm/s and 22.8±11.5 mL/min, respectively. IMA vessel diameter and blood flow were greater on the right than those on the left side in the same individual (P<0.01). In univariate analysis, sex and body surface area were the factors that influenced the size of the IMA vessel among different individuals, and by linear regression analysis, the size of the IMA vessel was only related to body surface area among different individuals. On univariate analysis, diabetes mellitus was the only factor affecting IMA blood flow, with a mean reduction in blood flow of 18.4% (left) and 21.7% (right) in the diabetic group (P<0.05).ConclusionPreoperative evaluation of the IMA using ultrasound over the parasternal second intercostal space is easy, noninvasive, and has a high success rate. The internal diameter of the IMA is positively correlated with body surface area, and blood flow is significantly reduced in patients with diabetes.

    Release date:2023-03-01 04:15 Export PDF Favorites Scan
  • Different intrathoracic anastomotic strategies for proximal esophageal dilatation in 654 patients with esophageal: A retrospective cohort study

    Objective To explore the strategy of intrathoracic anastomosis in patients with esophageal squamous cell carcinoma when the proximal esophagus is dilated to different degrees and explore its mechanism. Methods We retrospectively reviewed the clinical data of patients who underwent esophagectomy between 2014 and 2017 in West China Hospital. The patients were divided into two groups including a significant dilatation group with inner mucosal phase diameter (IMPD)≥17.9 mm and a non-significant dilatation group with IMPD<17.9 mm. And the patients were divided into two groups (a layered manual anastomosis group and a stapled anastomosis group) according to anastomosis method and propensity score matching was applied to adjust for potential confounders. Results We finally included 654 patients. There were 206 patients with 158 males and 48 females at average age of 62.21±7.72 years in the layerd manual analstomosis group and 448 patietns with 377 males and 71 females at average age of 62.57±8.42 years in the stapled anastomosis group. We also used Masson trichrome staining to assess the collagen fiber content in the esophagus. Compared with layered manual anastomosis, the incidence of anastomotic leakage was higher in the significant dilatation group than that in the stapled anastomosis group (original cohort: 3.8% vs. 10.7%, P=0.093; propensity score-matched cohort: 1.4% vs. 15.3%, P=0.004). And there was no significant difference in anastomotic leakage b etween layered manual anastomosis and stapled anastomosis in the non-significant dilatation group (original cohort: 4.7% vs. 4.2%, P=0.830; propensity score-matched cohort: 4.8% vs. 4.0%, P=0.206). Moreover, the average collagen fiber area ratio was significantly lower in the significant dilation group than that in the non-significant dilatation group (P=0.045). Conclusion There is a significant reduction in collagen fibers in the proximal esophageal wall tissue of esophageal squamous cell carcinoma patients with a IMPD≥17.9 mm. Intrathoracic layered manual anastomosis effectively reduces postoperative anastomotic leakage in these patients.

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  • Construction of Z-score reference ranges of fetal ductus arteriosus inner diameter during mid- and late-pregnancy

    ObjectiveTo establish the Z-score reference ranges of fetal arterial ductus (DA) inner diameter of normal fetus at 20 to 40 weeks’ gestation.MethodsA cross-sectional study was conducted in 781 normal singleton pregnancies with 20-40 weeks of gestation who underwent fetal echocardiography in the Third Affiliated Hospital of Henan University of Chinese Medicine from November 2018 to September 2019. The DA diameter, biparietal diameter (BPD), and femoral diaphysis length (FL) were measured and used to estimate gestational age (GA). With BPD, FL, and GA as independent variables and DA as dependent variables, linear regression analyses were conducted on the mean and standard deviation of each parameter to construct the best Z-score models.ResultsThe linear regression equations reflected strong positive correlations between the fetal biological growth parameter BPD, FL, GA, and fetal DA inner diameter. The heteroscedasticity of standard deviations was eliminated by the weighted regression of absolute stagger, and the best Z-score models were constructed. The linear regression equations of GA (week), BPD (mm), FL (mm), and DA inner diameter (mm) were as follows: Y=−2.661+0.217×GA, Y=−2.505+0.084×BPD, Y=−1.734+0.100×FL; the linear regression equations of GA (week), BPD (mm), FL (mm), and the standard deviation of DA inner diameter (mm) were as follows:Y=−0.273+0.025×GA, Y=−0.440+0.013×BPD, Y=−0.180+0.012×FL. According to the models, Z-score normal range reference values of fetal DA inner diameter were calculated.ConclusionsThere are good linear relationships between fetal DA inner diameter and GA, BPD and FL. The Z-score reference ranges of fetal DA diameter during mid- and late-pregnancy are constructed, which are helpful to quantitatively evaluate the normal development of fetal DA and provide a reference for clinical diagnosis of fetal DA abnormality.

    Release date:2020-10-26 03:00 Export PDF Favorites Scan
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