Strangulating volvulus of the ascending colon in horses.

The research article examines a form of intestinal twisting in horses, known as strangulating volvulus of the ascending colon, discussing its frequency in various seasons, the severity of the pain, and survival rates. The study was conducted on 57 horses and determined the relationship between the degree of volvulus, or twist, and the survival rates.

Subjects and Frequency of Volvulus

• A total of 57 horses were studied. These included 42 mares, 21 of whom were postparturient (had recently given birth), along with 8 stallions, and 7 geldings.
• The research indicated that volvulus was most common during the summer and spring months, with 24 cases occurring in summer and 17 in spring.

Pain Severity and Abdominal Fluid

• The level of pain in the horses was evaluated, showing severe pain in 41 horses, moderate in 9 horses, and mild in 4 horses.
• The study looked at the abdominal fluid from 30 of these horses and it was discovered that it varied – it was clear yellow for 19 horses, cloudy yellow for 3 horses, and serosanguineous in 8 horses.
• The protein content and nucleated cell count in the abdominal fluid were also measured. Protein was found to be around 2.5 +/- 1 g/dl, while the nucleated cell count was around 1,000 +/- 900 microliters.

Degree of Volvulus and Survival Rates

• It was found that 50 horses had a volvulus of 360 degrees or more, while 7 had a 270 degrees volvulus. 49 of these occurred in a counterclockwise direction.
• Survival rates were then worked out according to the degree of the twist. Horses with a volvulus of 360 degrees or greater had a survival rate of only 36%. Those with 270 degrees twist fared better with a 71% survival rate, showing that survival chances reduced with increased severity of the twist.

Vascular Occlusion and Nonsurvivors vs Survivors

• The study indicates that lower survival rates were due to severe vascular occlusion (blockage) in the colon in horses with a volvulus of 360 degrees or more.
• In non-surviving horses, the submucosa and lamina propria had more hemorrhage (bleeding) and edema (fluid retention) compared to surviving horses.
• In non-surviving horses, it was found that over 97% of the superficial epithelium, or outer tissue layer, was lost. In contrast, in horses that survived, around 60% of the cells were either lost or degenerated.

In conclusion, the research provides significant insights into the condition of strangulating volvulus of the ascending colon in horses, including tissue damage and survival chances based on the severity of the volvulus.