OBJECTIVE To compare antibacterial effects among 3 types of foam used with negative-pressure wound therapy (NPWT) in an ex vivo equine perfused wound model. SAMPLES Abdominal musculocutaneous flaps from 6 equine cadavers. PROCEDURES Each musculocutaneous flap was continuously perfused with saline (0.9% NaCl) solution. Four 5-cm circular wounds were created in each flap and contaminated with 106 CFUs of both Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA). After a 1-hour incubation period, 1 of 4 treatments (NPWT with silver-impregnated polyurethane foam [NPWT-AgPU], polyurethane foam [NPWT-PU], or polyvinyl alcohol foam [NPWT-PVA] or a nonadherent dressing containing polyhexamethylene biguanide without NPWT [control]) was randomly applied to each wound. An 8-mm punch biopsy specimen was obtained from each wound immediately before and at 6, 12, 18, and 24 hours after treatment application to determine the bacterial load for both P aeruginosa and MRSA. RESULTS The bacterial load of P aeruginosa for the NPWT-PVA treatment was significantly lower than that for the other 3 treatments at each sampling time after application, whereas the bacterial load for the NPWT-AgPU treatment was significantly lower than that for the NPWT-PU and control treatments at 12 hours after application. The bacterial load of MRSA for the NPWT-PVA treatment was significantly lower than that for the other 3 treatments at each sampling time after application. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that wounds treated with NPWT-PVA had the greatest decrease in bacterial load; however, the effect of that treatment on wound healing needs to be assessed in vivo.

This study evaluated the influence of temperature and organic load on the effectiveness of domestic bleach (DB), Surface Decontamination Foam (SDF), and Virkon in inactivating Geobacillus stearothermophilus spores, which are a surrogate for Bacillus anthracis spores. The spores were suspended in light or heavy organic preparations and the suspension was applied to stainless steel carrier disks. The dried spore inoculum was covered with the disinfectants and the disks were then incubated at various temperatures. At −20°C, the 3 disinfectants caused less than a 2.0 log10 reduction of spores in both organic preparations during a 24-h test period. At 4°C, the DB caused a 4.4 log10 reduction of spores in light organic preparations within 2 h, which was about 3 log10 higher than what was achieved with SDF or Virkon. In heavy organic preparations, after 24 h at 4°C the SDF had reduced the spore count by 4.5 log10, which was about 2 log10 higher than for DB or Virkon. In general, the disinfectants were most effective at 23°C but a 24-h contact time was required for SDF and Virkon to reduce spore counts in both organic preparations by at least 5.5 log10. Comparable disinfecting activity with DB only occurred with the light organic load. In summary, at temperatures as low as 4°C, DB was the most effective disinfectant, inactivating spores within 2 h on surfaces with a light organic candload, whereas SDF produced the greatest reduction of spores within 24 h on surfaces with a heavy organic load.

Objective-To determine the efficacy of decontamination and sterilization of a disposable port intended for use during single-incision laparoscopy. Sample-5 material samples obtained from each of 3 laparoscopic surgery ports. Procedures-Ports were assigned to undergo decontamination and ethylene oxide sterilization without bacterial inoculation (negative control port), with bacterial inoculation (Staphylococcus aureus, Escherichia coli, and Mycobacterium fortuitum) and without decontamination and sterilization (positive control port), or with bacterial inoculation followed by decontamination and ethylene oxide sterilization (treated port). Each port underwent testing 5 times; during each time, a sample of the foam portion of each port was obtained and bacteriologic culture testing was performed. Bacteriologic culture scores were determined for each port sample. Results-None of the treated port samples had positive bacteriologic culture results. All 5 positive control port samples had positive bacteriologic culture results. One negative control port sample had positive bacteriologic culture results; a spore-forming Bacillus sp organism was cultured from that port sample, which was thought to be an environmental contaminant. Bacteriologic culture scores for the treated port samples were significantly lower than those for the positive control port samples. Bacteriologic culture scores for the treated port samples were not significantly different from those for negative control port samples. Conclusions and Clinical Relevance-Results of this study indicated standard procedures for decontamination and sterilization of a single-use port intended for use during singleincision laparoscopic surgery were effective for elimination of inoculated bacteria. Reuse of this port may be safe for laparoscopic surgery of animals.

Objective—To evaluate the ability of industrial polystyrene foam insulation pads to redistribute loads placed on clinically normal weight-bearing structures of the foot and shift the location of the center of pressure palmarly in horses. Animals—25 nonlame mature horses. Procedures—Both forefeet from each horse were evaluated. Center of pressure data and solar load distribution patterns were recorded during a 5-second trial by use of a commercial pressure measurement system prior to placement of foam sole support and at 0, 6, 12, 24, and 48 hours after placement. Total contact surface area, contact pressure, peak contact pressure, and center of pressure positions were compared by use of a linear mixed model with repeated measurements. Results—Total contact surface area was increased significantly at all time points, whereas contact pressure and peak contact pressure were significantly decreased at all time points following application of foam sole supports. Immediately following application of sole support, the position of the center of pressure was significantly moved cranially. However, by 48 hours, the center of pressure was significantly positioned more palmarly than prior to application of the foam supports. Conclusions and Clinical Relevance—Results indicated that the use of foam sole supports may be an effective, economical, and immediate treatment for acute laminitis.