Flushing Technique Research Articles

Retrospective Comparative Study on Differences in Presence of Gas in the Aneurysm Sac After Evar in Early Post-operative Period Between Carbon Dioxide Flushing Technique and Saline Flushing of the Delivery-system

Introduction: Presence of gas is a frequent finding on early postoperative computed tomography angiography (CTA) after endovascular aortic aneurysm repair (EVAR) with unclear clinical relevance. The aim of this study was to examine and compare the presence of gas within the aneurysm sac following EVAR on early postoperative CTA after the use of carbon-dioxide (CO2) flushing technique with saline flushing alone. Methods: A retrospective analysis of patients undergoing standard, fenestrated EVAR (fEVAR) or branched EVAR (bEVAR) with flushing of the delivery system with CO2 between January 2016 and August 2018 was undertaken. Data of a previous report using standard saline flushing was included. Patients were classified into two main groups; group 1 with saline flushing and group 2 with CO2 flushing and three sub-groups according to the type of endo-graft. The presence, position and volume of gas in the postoperative CTA (within 10 days) was examined and analyzed in terms of anatomical and procedural risk factors. Results: Group 1 included 210 patients (mean age 73±8, 84% males) while Group 2 included 300 patients (mean age 70± 11, 68% males). Presence of gas was more common in group 1 (83; 39% vs. 64; 21%, p= 0.000). Volume of gas was larger in group 1 (0.41ml; (0.01-2.7) vs. 0.2ml; (0.02 - 1), p= 0.001). In standard EVAR with saline flushing (subgroup 1a); 59 patients (45%) had presence of gas and with CO2 flushing (subgroup2a); 35 patients (25%) had presence of gas (p= 0.005). The mean gas volume was larger in subgroup 1a compared to 2a (0.40± 0.47ml vs 0.15± 0.17ml, p= 0.000). The location of the gas was more frequent in contact with the anterior wall of the aorta in both groups, standard EVAR subgroups and fEVAR subgroups. The presence of gas in group 2 was associated with larger pre-operative size of the aortic diameter (p= 0.03) and larger perfused lumen diameter (p= 0.05). The type of the graft was not associated with the presence of gas in the aneurysm sac on post-operative CTA. However, the presence of gas was more frequent in standard EVAR than fEVAR and bEVAR. Endoleak type II was not associated with the presence of gas. Conclusion: CO2 flushing of stent-grafts during standard and complex EVAR prior to deployment reduces the frequency and volume of gas on post-operative CTA. This study indicates, that the CO2 flushing technique may effectively exchange trapped air for a less harmful gas in endo-grafts. Disclosure: Tilo Kölbel has intellectual property with Cook Medical, receives royalties, research, travel and educa-tional grants, speaking fees and is consultant and proctor with Cook Medical. Nikolaos Tsilimparis re-ceives travel and educational grants, speaking fees and is proctor with Cook Medical.

Retrospective Comparative Study on Differences in Presence of Gas in the Aneurysm Sac after Endovascular Aortic Aneurysm Repair in Early Postoperative Period between Carbon Dioxide Flushing Technique and Saline Flushing of the Delivery System

Presence of gas is a frequent finding on early postoperative computed tomography angiography (CTA) after endovascular aortic aneurysm repair (EVAR) with unclear clinical relevance. The aim of this study is to examine and compare the presence of gas within the aneurysm sac following EVAR on early postoperative CTA after the use of carbon dioxide (CO2) flushing technique with saline flushing alone. A retrospective analysis of patients undergoing standard, fenestrated EVAR (fEVAR) or branched EVAR (bEVAR) with flushing of the delivery system with CO2 between January 2016 and August 2018 was undertaken. Data of a previous report using standard saline flushing were included. Patients were classified into 2 main groups: group 1 with saline flushing and group 2 with CO2 flushing and 3 subgroups according to the type of endograft. The presence, position, and volume of gas in the postoperative CTA (within 10days) was examined and analyzed in terms of anatomical and procedural risk factors. Group 1 included 210 patients (mean age 73±8, 84% males), while group 2 included 300 patients (mean age 70±11, 68% males). Presence of gas was more common in group 1 (83, 39% vs. 64, 21%, P=0.000). Volume of gas was larger in group 1 [0.41mL (0.01-2.7) vs. 0.2mL (0.02-1), P=0.001). In standard EVAR with saline flushing (subgroup 1a), 59 patients (45%) had presence of gas with CO2 flushing (subgroup 2a); 35 patients (25%) had presence of gas (P=0.005). The mean gas volume was larger in subgroup 1a compared to 2a (0.40±0.47 vs. 0.15±0.17mL, P=0.000). The location of the gas was more frequent in contact with the anterior wall of the aorta in both groups, standard EVAR subgroups and fEVAR subgroups. The presence of gas in group 2 was associated with larger preoperative size of the aortic diameter (P=0.03) and larger perfused lumen diameter (P=0.05). The type of the graft was not associated with the presence of gas in the aneurysm sac on postoperative CTA. However, the presence of gas was more frequent in standard EVAR than fEVAR and bEVAR. Endoleak type II was not associated with the presence of gas. CO2 flushing of stent grafts during standard and complex EVAR prior to deployment reduces the frequency and volume of gas on postoperative CTA. This study indicates that the CO2 flushing technique may effectively exchange trapped air for a less harmful gas in endografts.

Comparative Study on Characteristics of Semen Collected from Sahel Bucks Using Slicing Swim up and Mincing Flushing Technique

Comparative Study on Characteristics of Semen Collected from Sahel Bucks Using Slicing Swim up and Mincing Flushing Technique

Comparative Study on Characteristics of Semen Collected from Sahel Bucks Using Slicing Swim up and Mincing Flushing Technique

Comparative Study on Characteristics of Semen Collected from Sahel Bucks Using Slicing Swim up and Mincing Flushing Technique

Air Embolism During TEVAR: Liquid Perfluorocarbon Absorbs Carbon Dioxide in a Combined Flushing Technique and Decreases the Amount of Gas Released From Thoracic Stent-Grafts During Deployment in an Experimental Setting

Purpose:To investigate the influence of flushing thoracic stent-grafts with carbon dioxide and perfluorocarbon on the amount of gas released during stent-graft deployment in thoracic endovascular aortic repair (TEVAR). Materials and Methods: Ten TX2 ProForm thoracic stent-grafts were deployed into a water-filled container with a curved plastic pipe and flushed sequentially with carbon dioxide, 20 mL of liquid perfluorocarbon (PFC), and 60 mL of saline. Released gas was measured using a calibrated setup. The volume of released gas was compared with the results of an earlier published reference group, in which identical stent-grafts were flushed with 60 mL saline alone as recommended in the instructions for use. Results: The average amount of gas released in the test group was 0.076 mL, significantly lower (p<0.001) than the mean 0.79 mL of gas released in the reference group. Big bubbles appearing at the tip of the sheath when deployment was started were seen in all grafts of the reference group but in only 2 of the test group stent-grafts. Small bubbles were less frequent in the test group. Conclusion: The amount of gas released from thoracic stent-grafts during deployment can be influenced by different flushing techniques. The use of PFC in addition to the carbon dioxide flushing technique reduces the volume of gas released during deployment of tubular thoracic stent-grafts to a few microliters. This significant effect is presumably based on the high solubility of carbon dioxide in perfluorocarbon and could be a potential future approach to lower the risk of cerebral injury and stroke from air embolism during TEVAR.

Follicle Deviation in Miniature Mares

Endometritis constitutes a major problem in the management of broodmares; hence, diagnostic tests with a high sensitivity and specificity are highly appreciated. The aim of this study was to compare the results from endometrial, cytologic, and bacteriologic examinations obtained by a newly developed, double-guarded, flushing technique versus standard diagnostic tests, the double-guarded swab and biopsy. The described double-guarded flush technique requires the use of a disposable uterine flushing tube, a sanitary sleeve, a sterile steel speculum, and a 250 mL fluid bag. Endometrial biopsies, swabs, and low-volume lavage samples were obtained from 34 research mares at six different time points in four estrous cycles and were evaluated cytologically and bacteriologically. Endometrial biopsies from the first cycle (n = 34) were examined for the presence of polymorphonuclear neutrophils (PMNs) in the stratum compactum and stratum spongiosum and used as a gold standard for calculation of diagnostic sensitivity and specificity. In all samples, Escherichia coli was most frequently isolated (lavage, 30%; swab, 21%; and biopsy, 12%) followed by β-hemolytic streptococci (lavage, 11%; swab, 8%; and biopsy, 7%). Positive cytology was less likely to occur when E coli was isolated from the diagnostic tests compared with the growth of β-hemolytic streptococci. Isolation of pathogens from uterine samples was highly associated with the presence of PMNs in the stratum compactum and straum spongiosum on histology. Using the presence of PMNs in the tissue specimens as the gold standard for diagnosing endometritis, the sensitivity of low-volume lavage culture was 0.75 and the specificity was 0.72. In conclusion, the double-guarded, low-volume, lavage technique was a rapid and accurate method for diagnosing mares with endometritis, and the risk of false-positive samples is considered to be minimal compared with other flushing techniques described.

Progesterone and 5α-dihydroprogesterone (DHP) in Cyclic Mares, and in Ovariectomized Mares and Geldings After Progesterone Administration

Endometritis constitutes a major problem in the management of broodmares; hence, diagnostic tests with a high sensitivity and specificity are highly appreciated. The aim of this study was to compare the results from endometrial, cytologic, and bacteriologic examinations obtained by a newly developed, double-guarded, flushing technique versus standard diagnostic tests, the double-guarded swab and biopsy. The described double-guarded flush technique requires the use of a disposable uterine flushing tube, a sanitary sleeve, a sterile steel speculum, and a 250 mL fluid bag. Endometrial biopsies, swabs, and low-volume lavage samples were obtained from 34 research mares at six different time points in four estrous cycles and were evaluated cytologically and bacteriologically. Endometrial biopsies from the first cycle (n = 34) were examined for the presence of polymorphonuclear neutrophils (PMNs) in the stratum compactum and stratum spongiosum and used as a gold standard for calculation of diagnostic sensitivity and specificity. In all samples, Escherichia coli was most frequently isolated (lavage, 30%; swab, 21%; and biopsy, 12%) followed by β-hemolytic streptococci (lavage, 11%; swab, 8%; and biopsy, 7%). Positive cytology was less likely to occur when E coli was isolated from the diagnostic tests compared with the growth of β-hemolytic streptococci. Isolation of pathogens from uterine samples was highly associated with the presence of PMNs in the stratum compactum and straum spongiosum on histology. Using the presence of PMNs in the tissue specimens as the gold standard for diagnosing endometritis, the sensitivity of low-volume lavage culture was 0.75 and the specificity was 0.72. In conclusion, the double-guarded, low-volume, lavage technique was a rapid and accurate method for diagnosing mares with endometritis, and the risk of false-positive samples is considered to be minimal compared with other flushing techniques described.

Air Embolism During TEVAR

Purpose: To investigate the amount of gas released from Zenith thoracic stent-grafts using standard saline flushing vs the carbon dioxide flushing technique. Methods: In an experimental bench setting, 20 thoracic stent-grafts were separated into 2 groups of 10 endografts. One group of grafts was flushed with 60 mL saline and the other group was flushed with carbon dioxide for 5 minutes followed by 60 mL saline. All grafts were deployed into a water-filled container with a curved plastic pipe; the deployment was recorded and released gas was measured using a calibrated setup. Results: Gas was released from all grafts in both study groups during endograft deployment. The average amount of released gas per graft was significantly lower in the study group with carbon dioxide flushing (0.79 vs 0.51 mL, p=0.005). Conclusion: Thoracic endografts release significant amounts of air during deployment if flushed according to the instructions for use. Application of carbon dioxide for the flushing of thoracic stent-grafts prior to standard saline flush significantly reduces the amount of gas released during deployment. The additional use of carbon dioxide should be considered as a standard flush technique for aortic stent-grafts, especially in those implanted in proximal aortic segments, to reduce the risk of air embolism and stroke.

Carbon Dioxide Flushing Technique to Prevent Cerebral Arterial Air Embolism and Stroke During TEVAR

Purpose: To describe the technique of carbon dioxide (CO2) flushing of thoracic stent-grafts to reduce the risk of cerebral air embolism. Technique: To remove room air, thoracic stent-grafts were preoperatively flushed 2 minutes with carbon dioxide from a cylinder connected to the flushing chamber of the captor valves of Zenith custom-made endografts; this was followed by the standard saline flush. Thirty-six patients undergoing thoracic endovascular aortic repairs (TEVAR) involving the ascending aorta and the aortic arch received CO2-flushed Zenith endografts. One patient with a highly calcified arch experienced a minor stroke. Conclusion: Arterial air embolism is a potentially underappreciated problem of aortic endografting, especially in the proximal segments of the aorta. CO2 flushing may have the potential to reduce air embolization during TEVAR.

Diagnostic double-guarded low-volume uterine lavage in mares

Endometritis constitutes a major problem in the management of broodmares; hence, diagnostic tests with a high sensitivity and specificity are highly appreciated. The aim of this study was to compare the results from endometrial, cytologic, and bacteriologic examinations obtained by a newly developed, double-guarded, flushing technique versus standard diagnostic tests, the double-guarded swab and biopsy. The described double-guarded flush technique requires the use of a disposable uterine flushing tube, a sanitary sleeve, a sterile steel speculum, and a 250 mL fluid bag. Endometrial biopsies, swabs, and low-volume lavage samples were obtained from 34 research mares at six different time points in four estrous cycles and were evaluated cytologically and bacteriologically. Endometrial biopsies from the first cycle (n = 34) were examined for the presence of polymorphonuclear neutrophils (PMNs) in the stratum compactum and stratum spongiosum and used as a gold standard for calculation of diagnostic sensitivity and specificity. In all samples, Escherichia coli was most frequently isolated (lavage, 30%; swab, 21%; and biopsy, 12%) followed by β-hemolytic streptococci (lavage, 11%; swab, 8%; and biopsy, 7%). Positive cytology was less likely to occur when E coli was isolated from the diagnostic tests compared with the growth of β-hemolytic streptococci. Isolation of pathogens from uterine samples was highly associated with the presence of PMNs in the stratum compactum and straum spongiosum on histology. Using the presence of PMNs in the tissue specimens as the gold standard for diagnosing endometritis, the sensitivity of low-volume lavage culture was 0.75 and the specificity was 0.72. In conclusion, the double-guarded, low-volume, lavage technique was a rapid and accurate method for diagnosing mares with endometritis, and the risk of false-positive samples is considered to be minimal compared with other flushing techniques described.

Application of Biosurfactant Surfactin on Copper Ion Removal from Sand Surfaces with Continuous Flushing Technique

Abstract The potential of using the biosurfactant surfactin to remove adsorbed metal ions from sand surfaces with continuous flushing approaches was evaluated. With the surfactin solution flushing approach, low removal efficiency of 2–15% for copper ions was detected due to the contact of surfactin with copper ions occurring mainly in the inter-particle pore region. The channeling effect also contributed to the low removal efficiency. By incorporating foam in the flushing operation, the contact of surfactin with copper ions was enhanced due to reduced channeling effect. More copper ions with outer-sphere interaction type were thus available and the removal efficiency was increased. Increasing the surfactin concentration could increase the dynamic foaming capacity and lead to improved removal efficiency of 40%. The results demonstrated that the foam-enhanced solution flushing approach was efficient with a low usage of surfactin.

PP233-SUN: Reflux in Central Venous Catheters: Inter-Rater Reliability and Assessment of Syringe Type and Flushing Technique

PP233-SUN: Reflux in Central Venous Catheters: Inter-Rater Reliability and Assessment of Syringe Type and Flushing Technique

Remediation of Petroleum-Contaminated Loess Soil by Surfactant-Enhanced Flushing Technique

A laboratory study was carried out to evaluate the feasibility of in situ remediation of a loess soil site contaminated with diesel oil. Six nonionic and anionic surfactants were selected and compared. In experiments of diesel oil desorption using the anionic surfactants LAS and SDS, it was shown that diesel oil solubilization increased linearly with surfactant dose at bulk aqueous concentrations of the two surfactants in excess of the relative CMC. The slope of the organic compound concentration in the micellar phase versus the concentration in the aqueous phase was used to determine the molar solubilization ratio and the diesel oil mole fraction micelle-phase/aqueous-phase partition coefficient Km. The Km values calculated by an empirical model with diesel oil octanol–water partition were very similar to that derived using the curve slope approach. Aliphatic polyethenoxy ether (AEO9) and sodium alcohol polyethoxylated ether sulfate (AES) were chosen for soil flushing. Through column tests in the laboratory, the washing effectiveness of the two selected surfactants and the relevant optimal operation conditions were examined. The results showed that AEO9 was more effective than AES in the flushing of diesel oil from contaminated loess soil, whereas AES was still more than 10 times as effective than fresh water alone. A mixed surfactant solution of 0.8% (v/v) AEO9 and 0.1% (v/v) AES could significantly increase the removal efficiency by 10% when compared with that using AEO9 alone. It was estimated that using an amount of the mixed surfactant solution equal to 60 pore volumes would be able to remove 60% of the petroleum residue remaining in the contaminated unsaturated zone within 9 days. This laboratory study provided a suitable model for a “safe” remediation alternative in the contaminated loess soil field.

COLD-STORAGE PRESERVATION OF THE CANINE AND RAT PANCREAS PRIOR TO ISLET ISOLATION

Cold-storage preservation of the canine pancreas prior to islet isolation has previously been noted to reduce the intrasplenic islet autograft success rate; but the mechanism of this deleterious effect has not been determined. We undertook a study in both outbred dogs and Lewis (RT1-1) rats to determine the influence of cold-storage preservation interval, preservation solution, and flushing technique on islet yield and islet viability. The preservation solutions used were those that had proved most efficacious in preserving segmental canine pancreases--namely, the modifications of silica gel fractionated plasma (SGF-III and SGF-IV) and an hydroxyethylstarch/lactobionate solution (UW-1). In the first set of experiments, the traditional vascular flush was used; this was followed by storage at 4 degrees C. After brief periods of preservation (3 hr in the rat, 12 hr in the dog) there was a significant (P less than 0.006) reduction in islet yield. The reduced yields were similar with each solution tested, were made worse with increasing intervals of storage, and resulted in a significant reduction in autograft success rate. The second set of experiments examined the effect of using an intraductal flush prior to preservation, along with the effect of adding collagenase to the preservation fluid. Islet yields were maintained at control values in both animal models using preservation intervals of up to 24 hr. These islet yields produced auto- or isograft success rates similar to those obtained by transplanting freshly obtained tissue; verifying adequate islet viability. We recommend that a pre-storage ductal flush technique be used for cold-storage preservation of the pancreas prior to islet isolation and transplantation.

Coronary arteriography: prevention of thromboembolic complications using a pressure-drip flushing technique.

All selective coronary arteriographic examinations (1,833) performed in the authors' laboratory during a five-year period (1/1/70 to 12/31/74) were analyzed for mortality and total morbidity according to method used. During the first two years, the control period, the classic brachial artery cutdown (Sones) and percutaneous femoral artery puncture (Judkins) techniques were utilized. Mortality rate for the total 589 patients was 1.01%. This included a mortality of 0.26% (1/386) for the brachial arteriotomy method, and 2.5% (5/203) for the percutaneous femoral puncture approach. After introduction of the pressure-drip flushing technique, the subsequent three-year mortality rate for a total of 1,244 patients was 0.16%. This included an incidence of 0.17% (1/585) for brachial arteriotomy and 0.15% (1/659) for modified percutaneous puncture techniques. The morbidity incidence during the initial two-year period was 3.0% (18/589). This included an incidence of 2.0% for brachial arteriotomy and 5.0% for percutaneous puncture techniques. After institution of the new pressure-drip flushing technique the total incidence fell to 1.2% equally divided between arteriotomy and percutaneous techniques. Modification of the classic percutaneous femoral artery puncture techniques has resulted in major reduction of mortality and morbidity complications which are chiefly thromboembolic in nature. It has not significantly influenced local thrombotic complications of arteriotomy.