Axillary wounds in horses and the development of subcutaneous emphysema, pneumomediastinum and pneumothorax

Abstract

Summary Equine axillary wounds are common in horses. Severe and potentially life‐threatening complications that can result from axillary wounds include subcutaneous emphysema, pneumomediastinum and pneumothorax. This report describes the occurrence of these complications and appropriate treatment. Case records of 7 horses after sustaining an axillary wound are reviewed. Of these cases, all 7 developed subcutaneous emphysema, 5 developed a pneumomediastinum and 4 developed a pneumothorax. The time between the wound occurrence and the development of subcutaneous emphysema was able to be determined in 5 of the 7 cases. The mean ± s.d. time for the development of subcutaneous emphysema following initial injury was 3.2 ± 0.84 days (range 2–4 days). Resolution of subcutaneous emphysema was not achieved until the treatment included packing the wound to stop it from acting as a one‐way valve. Horses with a pneumothorax in respiratory distress were managed with thoracocentesis or placement of thoracic drains. Horses with a pneumothorax but without respiratory distress were treated with conservative management. All horses survived to discharge.

Atypical presentation of caecal perforation in two horses

“…Other potential causes of retroperitoneal and subcutaneous emphysema include clostridial myonecrosis (Peek and Semrad ), axillary wounds leading to dissection of gas through the fascial planes (Joswig and Hardy ) and dissecting communication with the respiratory tract (Trostle et al . ).…”

“…Other potential causes of retroperitoneal and subcutaneous emphysema include clostridial myonecrosis (Peek and Semrad 2002), axillary wounds leading to dissection of gas through the fascial planes (Joswig and Hardy 2013) and dissecting communication with the respiratory tract (Trostle et al 1995). In the cases reported here, there was no history of trauma, wounds, or systemic sepsis that would be expected if these other aetiologies of dissecting emphysema were causative or contributory.…”

Noninfectious causes of subcutaneous emphysema

“…It is important to remember that the entrapped air can travel along facial planes, resulting in a pneumomediastinum or even a potentially life‐threatening pneumothorax (Fowler et al . ; Joswig and Hardy ).…”

Pneumopericardium associated with blunt thoracic trauma in an adult horse

“…In the current report, we describe a case of pneumopericardium secondary to blunt thoracic trauma in an adult horse. Thoracic and cervical trauma have been associated with various serious complications due to the relatively superficial location of several vital structures (Hassel ; Joswig and Hardy ). In some cases, diagnosis is easily achieved by clinical examination and inspection of open wounds.…”