23 Jul 2018
David Rendle describes the treatment of a referred eight-month-old cob filly with scar tissue after a suspected acid attack.
David Rendle
Job Title
Performing releasing incisions around the right eye.
An eight-month-old cob filly was referred to Rainbow Equine Hospital with chemical burn injuries.
Burns – especially chemical ones – are rare in horses and, coupled with no published information on how best to treat them, Rainbow consulted with human burns and plastic surgeon Ryckie Wade, as well as Jamie Peyton – chief of service at the University of California, Davis William R Pritchard Veterinary Medicine Teaching Hospital integrative medicine service, who had been pioneering treatments for burns and methods of pain control in animals.
With Rainbow interested in tilapia fish skin dressings Dr Peyton had been using to treat veterinary burns patients, she – along with VN Krisie Vine; Dr Wade; and Rainbow specialists Jonathan Anderson, David Rendle and Kate Loomes – travelled to the UK to treat the horse, named Cinders. She became the first in the world with burns injuries to be treated with such bandages.
After Cinders’ skin had healed beneath the tilapia dressings, which were then removed, the weeks that followed involved daily dressing changes. Most of the damaged areas had healed, but on either side of her face and around her eyes, she had been left with bands of scar tissue.
Scar tissue always contracts, and the contraction on Cinders’ face had caused her eyelids to become pulled out of line and her top lip to become pulled upwards, exposing her teeth and gums.
The scarring gave Cinders an endearing smile, but the contracture had been gradually getting worse, so she underwent another general anaesthesia surgery to graft areas that had not completely healed and realign those distorted by scar tissue.
Surgery was performed at Rainbow, with burns and plastics surgeons from Pinderfields Hospital Trust in Wakefield joining the team to pool knowledge and find the best treatment options. A Rainbow specialist anaesthetist performed the anaesthetic and planned Cinders’ pain relief during and after the surgery.
The scar tissue was debrided and releasing incisions were made above Cinders’ nostrils, over her muzzle and around her eyes. Her muzzle and eyelids were then able to move into a more normal position. To prevent further contracture, the releasing incisions had skin grafts placed within them so new skin would grow across the gaps, stopping them closing. Any remaining scar tissue areas that did not have skin over them were also covered with skin grafts.
Split thickness skin grafts were taken from Cinders’ back. A dermatome was used to remove a tissue paper-thin layer of the skin surface that was then placed through another machine to create small slits in the skin, allowing it to increase in size and cover a larger area of the wound. The skin grafts were then shaped and sutured to Cinders’ face, and covered with protective dressings.
Within 30 minutes after the surgery, Cinders lifted her head, looked around and stood up, unflustered. Another 30 minutes later, she was back in her stable enjoying her lunch. Cinders was bright through the night and demonstrated her usual voracious appetite.
The next morning, her face was predictably swollen, but even with the dressings in place, it was clear her muzzle and eyelids are in a more normal position. Her face and back will be sore, but with the help of pain medications, her attitude, interest in surroundings and, needless to say, appetite are unchanged as a result of the surgery. The dressings will remain in place for a week to protect the grafts.
The main determinant in Cinders’ surgery success will be how well the skin grafts adhere to the underlying tissue. The biggest adherence impediment is infection, which is hard to manage in equines – especially in the muzzle and eyes, where it is not possible to completely cover the surgical sites.
The team is not expecting all grafts to remain in place, but are optimistic they will sufficiently remain to minimise further scarring. Further surgeries would typically be performed in humans with similar injuries, and may be necessary, but the team is anxious to minimise surgical intervention to minimise discomfort. Cinders’ skin graft back grazes are superficial and will heal rapidly.
The team is grateful to those from Rainbow and Pinderfields who donated time to treat Cinders, Zimmer for loaning equipment and people who donated to ensure she got the best of everything. A wrong is being righted.
