14
EQUINE VETERINARY EDUCATION / AE / JANUARY 2020
NPWT therapy for the first two horses. Oral antimicrobial therapy with trimethoprim-sulphonamide was given in Horse 3 for the duration of treatment at the medically trained owners insistence. The application of the NPWT did require a learning curve and the first horse required several early changes of the bandage due to loss of suction. However the application became easier with time and the latter two horses maintained their bandage without difficulty. No horse was noted to lie down during the hospital stay although they were not cross-tied to prevent this from happening. Horses were all discharged shortly after the NPWT was
removed as the wounds were judged to be sufficiently healed to no longer require intensive care (Fig 4). Instructions were given to continue with box rest for 2 weeks after discharge from the hospital followed by a slow return to athletic activity if desired. Follow-up conversation with the referring veterinarians
2 years after the horses had left the hospital revealed that all the wounds had completely healed without difficulty or recurrence of the bursitis. A small scar was visible at the site of the bursitis in all cases and in Horse 2 hair had failed to regrow at the site of the bursitis (Fig 5). Horses had returned to their intended use as pleasure riding horses.
Discussion
Fig 2: The same horse as Fig 1 (Horse 2) with the abnormal tissue excised and the NPWT therapy applied. A distal limb bandage has been placed and it supports the adhesive dressing placed above it.
Fig 3: Horse 1 with the NPWT applied in the stall. The apparatus and canister are attached firmly to the fluid hook in the stall with duct tape thereby allowing the horse to move freely in the box. The suction line is attached to the mane and then descends to the wound site. A sticky adhesive dressing and generous applications of adhesive spray are employed to seal the periphery of the wound to maintain continuous negative pressure. No distal limb bandage was used in this horse.
The clinical outcome was satisfactory as all the wounds filled in completely with healthy granulation tissue and contracted significantly during the NPWT therapy. Horse 1 had the NPWT for a total of 11 days, Horse 2 for 12 days total (Fig 4) and Horse 3 for 22 days. Nonsteroidal anti-inflammatories and antibiotics were not given throughout the duration of the
© 2018 EVJ Ltd
This is the first study to describe the successful application and tolerance of NPWT in a case series in horses. There are several interesting points that can be raised. First, the use of NPWT therapy was very well tolerated with no signs of discomfort or pain. Discomfort has been observed in human subjects with NPWT although this finding is not consistent (Borgquist et al. 2010; Ren et al. 2017). Discomfort during therapy does not appear to be an important consideration in horses based on these three adult horses. Second, a learning curve was noted for the ability to obtain a good seal around the wound as has been reported in other veterinary studies. We observed that the use of a razor to remove small hairs in addition to clipping, careful cleaning of the surrounding skin, drying the skin, and the application of an adhesive spray to enhance stickiness, all appeared to help to maintain the seal. Complete coverage by adhesive spray (Vi-Drape)2 on the surrounding skin as well as allowing time for the spray to air- dry prior to application of the adhesive drape was also perceived to be important to obtain a long-lasting seal. Third, no problems of irritation of the surrounding skin were identified with the repeated applications of the adhesive spray or drapes (Fig 4). The site was unable to be covered by a protective bandage but occasionally a lower limb support bandage was placed along the most ventral aspect of the dressing to help maintain it in place (Fig 2). The choice of the amount of pressure and the initial period
of continuous negative pressure followed by intermittent negative pressure was influenced by studies in dogs and communications with small animal surgeons. The choice of
125 mmHg is common to most small animal studies (Pitt and Stanley 2014; Nolff et al. 2015). A continuous negative pressure
was used for the first 24 h to accustom the horse to the apparatus and then changed to an intermittent negative pressure as some studies have shown this to be advantageous with improved granulation tissue formation (Borgquist et al. 2010; Malmsjo et al. 2012; Stanley 2017). The choice to change the dressing every 3–4 days was also based on use in small
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76
