Preliminary study to evaluate the use of fast abdominal ultrasonography of horses with colic in first opinion ambulatory practice

Summary Background Colic is the commonest emergency in first opinion equine practice. Early referral is important for horses requiring surgery. Fast localised abdominal ultrasonography of horses (FLASH) is frequently used as a diagnostic tool in the investigation of colic at referral hospitals, but its use in first opinion practice has not been evaluated. Objective To assess the value of FLASH scanning in the primary assessment of horses with colic in the field, using a portable wireless ultrasound system. Study design Prospective study (2018–2021). Methods Any horse examined for colic as an emergency in a first opinion ambulatory practice was eligible for inclusion in the study. A FLASH examination was performed using a wireless handheld ultrasound scanner, with the images displayed on a smartphone or tablet. The findings on FLASH scans and the outcome of the case (recovered, referred for surgery or euthanised without referral) were recorded. Results In total, 135 equids with acute colic were evaluated. Of the 135 horses, 49 (36%) had an abnormal finding on FLASH scanning, including distended loops of small intestine (n = 34), thickened small intestinal walls (n = 23) and/or distension of the stomach (n = 7). Reduced small intestinal motility was recorded in 52 animals (38%). Follow‐up information was available in all animals: 50 (37%) were euthanised due to clinical deterioration and the owners' decision not to undertake surgery; 85/135 (63%) survived, including 5/85 (6%) that underwent surgery and 80/85 (94%) that resolved with medical management. Main limitations Small number of cases. Lack of results of post‐mortem examination of horses that were euthanised. Potential selection bias. Conclusion The FLASH technique can be valuable in the primary assessment of horses with colic in first opinion ambulatory practice. Further evaluation with more cases is required.