scholarly journals Ex vivo evaluation of a multilayered sealant patch for watertight dural closure: cranial and spinal models

Author(s):  
A. Kinaci ◽  
S. van Thoor ◽  
S. Redegeld ◽  
M. Tooren ◽  
T. P. C. van Doormaal

AbstractCerebrospinal fluid leakage is a frequent complication after cranial and spinal surgery. To prevent this complication and seal the dura watertight, we developed Liqoseal, a dural sealant patch comprising a watertight polyesterurethane layer and an adhesive layer consisting of poly(DL-lactide-co-ε-caprolactone) copolymer and multiarmed N-hydroxylsuccinimide functionalized polyethylene glycol. We compared acute burst pressure and resistance to physiological conditions for 72 h of Liqoseal, Adherus, Duraseal, Tachosil, and Tisseel using computer-assisted models and fresh porcine dura. The mean acute burst pressure of Liqoseal in the cranial model (145 ± 39 mmHg) was higher than that of Adherus (87 ± 47 mmHg), Duraseal (51 ± 42 mmHg) and Tachosil (71 ± 16 mmHg). Under physiological conditions, cranial model resistance test results showed that 2 of 3 Liqoseal sealants maintained dural attachment during 72 hours as opposed to 3 of 3 for Adherus and Duraseal and 0 of 3 for Tachosil. The mean burst pressure of Liqoseal in the spinal model (233 ± 81 mmHg) was higher than that of Tachosil (123 ± 63 mmHg) and Tisseel (23 ± 16 mmHg). Under physiological conditions, spinal model resistance test results showed that 2 of 3 Liqoseal sealants maintained dural attachment for 72 hours as opposed to 3 of 3 for Adherus and 0 of 3 for Duraseal and Tachosil. This novel study showed that Liqoseal is capable of achieving a strong watertight seal over a dural defect in ex vivo models.

2016 ◽  
Vol 42 (2) ◽  
pp. 95-98 ◽  
Author(s):  
Luis Gustavo Abdalla ◽  
Karina Andrighetti de Oliveira Braga ◽  
Natalia Aparecida Nepomuceno ◽  
Lucas Matos Fernandes ◽  
Marcos Naoyuki Samano ◽  
...  

Objective: To evaluate the use of ex vivo lung perfusion (EVLP) clinically to prepare donor lungs for transplantation. Methods: A prospective study involving EVLP for the reconditioning of extended-criteria donor lungs, the criteria for which include aspects such as a PaO2/FiO2 ratio < 300 mmHg. Between February of 2013 and February of 2014, the lungs of five donors were submitted to EVLP for up to 4 h each. During EVLP, respiratory mechanics were continuously evaluated. Once every hour during the procedure, samples of the perfusate were collected and the function of the lungs was evaluated. Results: The mean PaO2 of the recovered lungs was 262.9 ± 119.7 mmHg at baseline, compared with 357.0 ± 108.5 mmHg after 3 h of EVLP. The mean oxygenation capacity of the lungs improved slightly over the first 3 h of EVLP-246.1 ± 35.1, 257.9 ± 48.9, and 288.8 ± 120.5 mmHg after 1, 2, and 3 h, respectively-without significant differences among the time points (p = 0.508). The mean static compliance was 63.0 ± 18.7 mmHg, 75.6 ± 25.4 mmHg, and 70.4 ± 28.0 mmHg after 1, 2, and 3 h, respectively, with a significant improvement from hour 1 to hour 2 (p = 0.029) but not from hour 2 to hour 3 (p = 0.059). Pulmonary vascular resistance remained stable during EVLP, with no differences among time points (p = 0.284). Conclusions: Although the lungs evaluated remained under physiological conditions, the EVLP protocol did not effectively improve lung function, thus precluding transplantation.


2002 ◽  
Vol 48 (11) ◽  
pp. 2030-2043 ◽  
Author(s):  
Glenn F Billman ◽  
Amy B Hughes ◽  
Golde G Dudell ◽  
Elizabeth Waldman ◽  
Lisa M Adcock ◽  
...  

Abstract Background: The management of critically ill infants and neonates includes frequent determination of arterial blood gas, electrolyte, and hematocrit values. An objective of attached point-of-care patient monitoring is to provide clinically relevant data without the adverse consequences associated with serial phlebotomy. Methods: We prospectively determined the mean difference (and SD of the difference) from laboratory methods of an in-line, ex vivo monitor, the VIA LVM Blood Gas and Chemistry Monitoring System® (VIA LVM Monitor; Metracor Technologies, Inc.), in 100 critically ill neonates and infants at seven children’s hospitals. In doing so, we examined monitor stability with continuous use. In vivo patient test results from laboratory benchtop analyzers were compared with those from the VIA LVM Monitor on paired samples. In a separate in vitro comparison, benchtop analyzer and monitor test results were compared on whole-blood split samples. Results: A total of 1414 concurrent, paired-sample measurements were obtained. The mean differences (SD of differences) from laboratory methods and r values for the combined data for the VIA LVM Monitor from the seven sites were 0.001 (0.026) and 0.97 for pH, 0.7 (3.6) mmHg and 0.94 for Pco2, 4.2 (9.6) mmHg and 0.98 for Po2, 0.0 (2.9) mmol/L and 0.87 for sodium, 0.1 (0.2) mmol/L and 0.96 for potassium, and 0.3% (2.9%) and 0.90 for hematocrit. Performance results were similar among the study sites with increasing time of monitor use and between in vivo paired-sample and in vitro split-sample test results. Conclusion: The VIA LVM Monitor can be used to assess critically ill neonates and infants.


2005 ◽  
Vol 6 (1) ◽  
pp. 38 ◽  
Author(s):  
Sunil P. Malhotra ◽  
David Le ◽  
Stephan Thelitz ◽  
Frank L. Hanley ◽  
R. Kirk Riemer ◽  
...  

<P>Background: Advances in robotic technology have enabled a wider range of applications for minimally invasive techniques in cardiac surgery, including mitral valve repair and coronary artery bypass grafting. With increased technical sophistication, robotic-assisted techniques can be developed for the endoscopic repair of certain congenital cardiac lesions. </P><P>Objective: The purpose of this study was to assess the feasibility of closed chest thoracic aortic anastomosis in a juvenile ovine model. </P><P>Methods: Lambs, aged 45 to 55 days, underwent surgery that was performed using the da Vinci robotic surgical system. Using 3 ports, the surgeon dissected the descending thoracic aorta and mobilized it free from attachments, using single-lung ventilation and CO<SUB>2</SUB> insufflation. Snares were introduced through 2 stab wounds for aortic occlusion proximally and distally. In 4 lambs, the aorta was completely transected and reanastomosed using interrupted nitinol sutures. One lamb underwent longitudinal aortotomy, and patch aortoplasty was performed with the placement of a Gore-Tex patch. Snares were released and the animals were recovered once hemodynamically stable. Animals were sacrificed at 6 to 12 hours after surgery and the descending aorta was harvested. Burst-pressure testing was performed on the anastomoses. </P><P>Results: All 5 lambs survived the procedure with stabilization of hemodynamic parameters following surgery. The mean aortic clamp time was 47 � 17 minutes, and the anastomosis was completed in 26 � 5 minutes. The mean burst pressure was 163 � 9 mm Hg. Conclusions: Endoscopic thoracic aortic anastomosis can be performed safely and with adequate exposure in a juvenile large-animal model using computer-assisted surgical techniques. With further refinements, these approaches could be applied to the repair of congenital anomalies of the aorta, including interrupted aortic arch and aortic coarctation.</P>


2016 ◽  
Vol 65 (05) ◽  
pp. 356-361 ◽  
Author(s):  
Katharina Waubke ◽  
Anika Pehl ◽  
Thorsten Steinfeldt ◽  
Detlef Bartsch ◽  
Andreas Kirschbaum

Background Every anatomical lung resection requires the airtight closure of at least one bronchus. In current clinical practice, these bronchi are sealed with sutures or staplers. This study investigated in an ex vivo pig model whether a new bipolar sealing device MARSEAL (KLS Martin, Tuttlingen, Germany) could be an alternative for this purpose. Methods Complete bronchial trees were prepared free from pig heart–lung blocks that were removed at a slaughterhouse. These preparations were taken to the laboratory, and main, lobar, and segmental bronchi were closed using sutures, staples, or bipolar sealing. Each trachea was then intubated and connected to a ventilating device. The initial airtight closure of the bronchus was first tested with lung-protective ventilation. After 15 minutes of ventilation, the inspiratory ventilation pressure was slowly increased and the burst pressure (in mbar) was recorded. Each group included 12 bronchus closures. Group mean burst pressures were compared using a nonparametric test (Mann–Whitney U test). The significance level was p < 0.05. Results The main bronchi closed both stapler magazines or sutures were all initially airtight during ventilation. The mean burst pressure was 60 ± 0 mbar for staplers and 57.92 ± 5.8 mbar for sutures. In contrast, 50% of main bronchi sealed with MARSEAL devices (5 or 10 mm) leaked air from the beginning. This was also noted in all lobar bronchi sealed with the MARSEAL 5-mm device and 80% of those sealed with the MARSEAL 10-mm device. The mean burst pressure of initially airtight lobar bronchi was 12.7 ± 7.25 mbar. In contrast, all segmental bronchi (mean width: 1.6 cm) were airtight when ventilated. Mean burst pressure was 14.64 ± 9.1 mbar with the MARSEAL 5-mm device and 29.64 ± 21.3 mbar with the MARSEAL 10-mm device. Histological investigation of the preparations (with hematoxylin and eosin staining) showed intact cartilaginous structures that were largely unaffected by bipolar coagulation. The airtight sealing of the segmental bronchi resulted from fusion of the peribronchial tissue and not the cartilage. Conclusion Bipolar sealing is an inappropriate tool for the closure of the bronchi in comparison to suture or stapling.


2012 ◽  
Vol 23 (3) ◽  
pp. 199-204 ◽  
Author(s):  
Bruno Carvalho de Vasconcelos ◽  
Leonardo de Alencar Matos ◽  
Elilton Cavalcante Pinheiro-Júnior ◽  
Antônio Sérgio Teixeira de Menezes ◽  
Nilton Vivacqua-Gomes

This study evaluated the accuracy of three electronic apex locators (Root ZX, Novapex, and Justy II) in root canal length determinations using different apical file sizes, considering the apical constriction (AC) and the major foramen (MF) as anatomic references. The diameter of the apical foramina of 40 single-rooted teeth was determined by direct visual measurement and the master apical file was established. Electronic measurements were then performed using 3 instruments: the selected master apical file (adjusted file), one size smaller (intermediate file), and two sizes smaller (misfit file). The distances from the tip of files fixed in the canals to the MF and to the AC were measured digitally. Precision at AC and at MF for the misfit, intermediate and adjusted apical files was as follows: 80%/88%/83% and 78%/83%/95% (Root ZX); 80%/85%/80% and 68%/73%/73% (Novapex); and 78%/80%/78% and 65%/78%/70% (Justy II). Considering the mean discrepancies, statistically significant differences were found only for the adjusted file at MF, with Root ZX presenting the best results at MF. The chi-square test showed significant differences between the acceptable measurements at AC and at MF for the Justy II and Novapex (± 0.5 mm) regardless of file adjustment. Under the conditions of the present study, all devices provided acceptable electronic measurements regardless of file adjustment, except for Root ZX which had its performance improved significantly when the precisely fit apical file was used. Justy II and Novapex provided electronic measurements nearest to the AC.


2017 ◽  
Vol 22 (6) ◽  
pp. 56-60 ◽  
Author(s):  
Carla Y. Kong-Zárate ◽  
Marcos J. Carruitero ◽  
Will A. Andrews

ABSTRACT Objective: The purposes of this investigation were to determine the horizontal distances between the mandibular posterior teeth and the WALA ridge in a sample of Peruvians with normal occlusion and to compare them by tooth type, sex, arch side, and age groups. Methods: 65 dental casts of subjects with normal occlusion were collected. Posterior teeth, except for third molars, were evaluated. The horizontal distances between the occluso-gingival midpoints of the buccal surfaces (FA points) of each tooth and the WALA ridge were measured using a modified digital caliper. The values between each different tooth type within the sample were compared using the ANOVA and Scheffe tests, while comparisons by sex, arch side and age groups, using the Student’s t-test. Results: The mean distances in the sample was 0.96 mm for first premolars, 1.45 mm for second premolars, 2.12 mm for first molars and 2.55 mm for second molars. Statistically significant differences between each of the four tooth types were found. There were no significant differences found between sex, arch side and age groups. Conclusion: The horizontal distances between the mandibular posterior teeth and the WALA ridge increased progressively from the first premolars to the second molars in Peruvians with normal occlusion. The WALA ridge was a good landmark to evaluate the positions of posterior teeth in Peruvians with normal occlusion.


2016 ◽  
Vol 29 (2) ◽  
pp. 317-324 ◽  
Author(s):  
Lidiane Angélica Cotelez ◽  
Maysa Venturoso Gongora Buckeridge Serra ◽  
Eliane Ramos ◽  
José Eduardo Zaia ◽  
Flávia Oliveira Toledo ◽  
...  

Abstract Introduction: Muscle fatigue can be defined as a decrease in the performance of the neuromuscular system in generating force. This situation is considered a complex physiological process involving various body systems, in order to avoid irreversible damage or even cell death. Objective: The aim of this study was to measure muscle strength in order to assess the level of fatigue among footwear industry workers, and to determine a possible correlation between muscle strength and the perception of reported fatigue. Materials and Methods: The study included 32 male workers from the footwear industry with a mean age of 34.63 ± 11.98 years. The workers performed the handgrip strength test using a handheld dynamometer, and completed the Bipolar Fatigue Questionnaire. Results: The mean result of strength testing was 23.1 ± 8.3 kgf, and the mean score of the fatigue questionnaire was 2.28 ± 0.93 points. However, a low correlation was observed between the results of the fatigue questionnaire and the strength test results. Conclusion: The grip strength results of the footwear workers were below the values for the general Brazilian population, a fact that may indicate potential muscle fatigue. However, a low correlation with the perception of fatigue was indicated by the questionnaire.


Physiotherapy ◽  
2017 ◽  
Vol 24 (2) ◽  
Author(s):  
Stanisław Gadziński ◽  
Agata Masłoń ◽  
Dorota Czechowska ◽  
Joanna Golec ◽  
Elżbieta Szczygieł ◽  
...  

AbstractIntroduction. The aim of the study was to assess the functional status of male soccer players in different age groups who played on different surfaces. Methods. The study included 45 soccer players aged 13-35 years. Among them, 15 were junior players, 15 were players of the senior Silesia-Opole 3rd league (SL), and 15 were senior players in the futsal Extra Class league (SF). The functional status and basic motor skills were assessed according to the results obtained in seven motor tasks included in the Functional Movement Screen™ (FMS) test. Results. The mean total scores in the FMS test were statistically significantly higher among both senior futsal and senior 3


2012 ◽  
Vol 95 (4) ◽  
pp. 1059-1063 ◽  
Author(s):  
Stephen F Tomasino ◽  
Rebecca M Pines ◽  
Gordon Hamilton

Abstract The AOAC Use-Dilution Methods, 955.15 (Staphylococcus aureus) and 964.02 (Pseudomonas aeruginosa), were revised in 2009 to include a standardized procedure to measure the log density of the test microbe and to establish a minimum mean log density value of 6.0 (geometric mean of 1.0 × 106 CFU/carrier) to qualify the test results. This report proposes setting a maximum mean log density value of 7.0 (geometric mean of 1.0 × 107 CFU/carrier) to further standardize the procedure. The minimum value was based on carrier count data collected by four laboratories over an 8-year period (1999–2006). The data have been updated to include an additional 4 years' worth of data (2006–2010) collected by the same laboratories. A total of 512 tests were conducted on products bearing claims against P. aeruginosa and S. aureus with and without an organic soil load (OSL) added to the inoculum (as specified on the product label claim). Six carriers were assayed in each test, for a total of 3072 carriers. Mean log densities for each of the 512 tests were at least 6.0. With the exception of two tests, one for P. aeruginosa without OSL and one for S. aureus with OSL, the mean log densities did not exceed 7.5 (geometric mean of 3.2 × 107 CFU/carrier). Across microbes and OSL treatments, the mean log density (±SEM) was 6.80 (±0.07) per carrier (a geometric mean of 6.32 × 106 CFU/carrier) and acceptable repeatability (0.28) and reproducibility (0.31) SDs were exhibited. A maximum mean log density per carrier of 7.0 is being proposed here as a validity requirement for S. aureus and P. aeruginosa. A modification to the method to allow for dilution of the final test cultures to achieve carrier counts within 6.0–7.0 logs is also being proposed. Establishing a range of 6.0–7.0 logs will help improve the reliability of the method and should allow for more consistent results within and among laboratories.


2013 ◽  
Vol 690-693 ◽  
pp. 2371-2378
Author(s):  
Wei Pu Xu ◽  
Yi Ting Liu

A brief overview is given in the conventional domed bursting disc structure and manufacturing method. 316L stainless steel as a template is selected. With the investigation on bursting disc material tensile test method, the test results are summarized,also the burst results of disc burst pressure in different sizes. With the help of bursting disc material performance test and bursting disc burst pressure test of 316L , the test results provide a reference for other types of bursting disc.


Sign in / Sign up

Export Citation Format

Share Document