Objective—To evaluate manufacturing variability, diffusion of filling solutions, and maintenance of occlusion over time in 3 sizes of silicone hydraulic occluders (HOs).
Sample Population—2-, 5-, and 20-mm HOs (HO2, HO5, and HO20, respectively).
Procedures—Manufacturing variability was analyzed by comparing variation in internal luminal areas and filling volumes within each size group. Occluders were filled to 100% occlusion with air (n = 4), saline (0.9% NaCl) solution (4), or sodium hyaluronate (4) and submerged in simulated body fluid. Changes in luminal area and weight were recorded for 133 days to evaluate maintenance of occlusion.
Results—Considerable variability in uninflated luminal area and fill volumes was observed among the 3 sizes of HOs. Loss of occlusion developed in the first 12 hours in all air-filled HOs. Fluid-filled occluders were reliable in maintenance of occlusion after 133 days (99.99% for HO20, 99.59% for HO5, and 90.40% for HO2), although diffusion of saline solution and hyaluronate from all HOs was confirmed by detection of significant decreases in weight over time. There was no significant difference in weight loss between HOs filled with saline solution and HOs filled with sodium hyaluronate.
Conclusions and Clinical Relevance—Saline solution or sodium hyaluronate may be used as a filling solution in the HOs tested. Maintenance of occlusion was best in the larger sizes. Saline solution or sodium hyaluronate should be used in future clinical investigations of HOs. Retrograde filling to remove air should be used when filling HOs with fluid.
Objective—To evaluate efficacy of a hydraulic occluder (HO) used for treatment of dogs with an intrahepatic portosystemic shunt (IHPSS).
Animals—10 dogs with an IHPSS.
Procedures—Serum biochemical and postprandial bile acids (PPBA) analyses and transcolonic scintigraphy were performed before surgery. Laparotomy was performed, and an uninflated HO was placed around the portal vein branch leading to the IHPSS. After surgery, 0.9% NaCl solution was injected into subcutaneous injection ports at 2, 4, 6, and 8 weeks to achieve staged occlusion of the HO. Serum biochemical analyses, PPBA analysis, and scintigraphy were performed 2 weeks after occlusion. Serum biochemical analyses were repeated 1 year after surgery.
Results—Implant revision was required in 3 dogs because of rupture of the HO (n = 2) or detachment of the actuating tubing (1). Serum biochemical values and clinical signs improved in all dogs after surgery. Six of 10 dogs had PPBA concentration within reference range 2 weeks after occlusion, and 2 additional dogs had concentrations within reference range at 1 year. Only 5 of 10 dogs had complete resolution of portosystemic shunting 2 weeks after occlusion. Two dogs were lost to follow-up, and 8 dogs remained alive with no recurrence of clinical signs at a median of 22 months after surgery.
Conclusions and Clinical Relevance—Use of the HO appeared to be an effective method for surgical treatment for dogs with IHPSS, although problems with implant reliability indicate a need for modifications in design and manufacturing.
To evaluate the efficacy of ethylene oxide (EtOH) sterilization of 4 different waterproof camera cases and the ability of those sterilized cases to maintain a sterile barrier for intraoperative camera use.
3 action cameras, 1 smartphone, and associated waterproof cases.
Cases were inoculated by immersion in medium containing Staphylococcus pseudintermedius, Escherichia coli, and Pseudomonas aeruginosa and then manually cleaned and subjected to EtOH sterilization. Cameras were disinfected, loaded into sterile cases, and sterilely operated for 2 hours. Samples were collected from cases after inoculation, EtOH sterilization, camera loading, and 1 and 2 hours of operation and from all cameras after 2 hours of operation. Procedures were repeated twice, followed by an additional challenge round wherein cameras were purposefully contaminated prior to loading. All samples underwent bacterial culture.
All cases were successfully sterilized, and loading of nonsterile cameras into sterile cases caused no contamination when cameras had been disinfected beforehand. Nonpathogenic environmental contaminants were recovered from 6 of 64 culture samples and 2 of 4 room samples. During the challenge round, only the postload sample for 1 case yielded E coli, suggesting sterile glove contamination; however, postload, 1-hour, and 2-hour samples for the GoPro case yielded E coli and S pseudintermedius, suggesting major contamination.
CONCLUSIONS AND CLINICAL RELEVANCE
Results suggested that the evaluated cases can be safely sterilized with EtOH and used for image acquisition by aseptically prepared surgeons when cameras are disinfected prior to loading. Except for the GoPro camera, camera use did not jeopardize sterile integrity.
Objective—To biomechanically and histologically compare single-layer continuous Cushing and simple continuous appositional cystotomy closure in rats with xylene-induced cystitis.
Animals—40 female Sprague-Dawley rats.
Procedure—Rats were anesthetized, their urinary bladders catheterized and evacuated, and xylene instilled in each bladder for 5 minutes and then aspirated. Forty-eight hours later, ventral midline celiotomy and cystotomy (8 mm) were performed. Cystotomies were closed with 6-0 poliglecaprone 25 by use of a single-layer continuous Cushing or simple continuous appositional pattern (20 rats/group), and cystotomy times were recorded. Rats were allocated to healing durations (5 rats/group) of 0, 3, 7, and 14 days. Celiotomies were closed in a routine manner. After the allotted healing interval, another celiotomy was performed, the urethra cannulated, and ureters ligated. The cannula was secured to the urethra, and the bladder infused at 0.1 mL/min. Leak pressure volume, leak pressure, peak pressure volume, and peak pressure were recorded via a pressure transducer. Bladders were harvested and histologically assessed.
Results—Cystotomy time, biomechanical testing values, and overall inflammation scores did not differ between closure methods for any healing duration. Both methods had significantly greater leak pressures, with the appositional method also having significantly greater peak pressures on day 7, compared to day 0. Biomechanical testing values decreased from day 7 to 14 as a result of juxtaincisional weakening of the bladder and xylene-induced changes in collagen.
Conclusions and Clinical Relevance—Simple continuous appositional was equal biomechanically and histologically to continuous Cushing for all comparison variables. Poliglecaprone 25 was acceptable for cystotomy closure.