Summary Reasons for performing study: Few studies have assessed short‐ and long‐term complication rates of horses following surgical treatment of colic, a potentially fatal condition. Complications can lead to patient discomfort and increased costs; knowledge of predisposing factors may help to reduce complication rates. Objectives: To document and analyse short‐term complications in 300 horses undergoing colic surgery, and to assess some of the possible predisposing factors. Methods: History, clinical findings, surgical findings and procedures, and post operative treatments of 300 consecutive surgical colic cases (1994–2001) were reviewed. Comparisons among groups of discrete data were made using chi‐squared or Student's t tests as appropriate. Results: Short‐term complications in 227 horses following a single laparotomy included colic/pain (28.2%), incisional drainage or infection (26.9%), post operative ileus (13.7%), severe endotoxaemic shock (12.3%), jugular thrombophlebitis (7.5%), septic peritonitis (3.1%) and colitis/diarrhoea (2.2%). Horses with small bowel obstruction had a higher rate of post operative ileus than those with large bowel obstruction. Rates of post operative pain and shock were higher in horses with small colon rather than large colon obstruction, and in those that had an ischaemic rather than a simple obstruction. The rate of wound complications increased with increasing total plasma protein concentration at admission. Horses that had a repeat laparotomy had a higher rate of wound complications compared to those that had a single laparotomy. Application of a stent bandage was associated with a higher rate of wound complications than if no stent was applied; however, application of an incise drape over the wound for recovery was associated with a lower rate of wound complications than for horses that had no protective covering of the wound. Conclusions: The most common short‐term post operative complications following colic surgery were pain, incisional drainage, ileus, endotoxaemiac shock and jugular thrombophlebitis. Some factors that appeared to predispose to these complications were identified. Although many of these factors related to the underlying disease process, a number of factors, including surgical techniques, were identified that might be amenable to modification. Potential relevance: Prospective studies to assess the effects of modifying these factors on survival rates should be performed.

Summary Reasons for performing study: A minority of equine colic cases prove fatal unless treated surgically; however, few studies have considered long‐term survival and complication rates, and few have attempted to identify factors that might affect outcomes. Such information is required for owners and veterinary surgeons to make informed decisions about the most appropriate treatment for individual cases. Objectives: To document short‐term survival rates of 300 horses undergoing colic surgery and analyse factors that might have predisposed to short‐term death. Methods: History, clinical and surgical findings, treatments and outcomes of 300 surgical colic cases (1994–2001) were reviewed. Comparisons among groups of discrete data were made using chi‐squared or Student's t tests as appropriate. Significance was set at P<0.05, and 95% confidence intervals were calculated for percentages. Results: The short‐term survival rate (to discharge) was 70.3% for all horses and 83.1% for those recovering from anaesthesia; for horses that had a single laparotomy it was 87.2%. The most common reasons for death/euthanasia in the post operative period after a single laparotomy were persistent pain/colic, post operative ileus and grass sickness. Horses with lesions involving the small intestine and caecum had lower survival rates (75.2 and 66.7%, respectively) than those with large colon or small colon lesions (89.9 and 100%, respectively). The survival rate for ischaemic/strangulating lesions (68.9%) was lower than for simple obstructions (90.5%). Conclusions: Short‐term survival of horses undergoing exploratory laparotomy for acute colic is dependent on many factors, including the nature of the underlying disease, cardiovascular status and post operative complications. Potential relevance: These retrospective studies may be used as a basis for prospective studies assessing treatments that could ultimately improve survival and decrease complication rates.

Summary Reasons for performing study: Few studies have evaluated long‐term survival and complication rates in horses following surgical treatment of colic, making it difficult to offer realistic advice concerning long‐term prognosis. Objective: To review the complications occurring after discharge from hospital and survival to >12 months after surgery of 300 horses undergoing exploratory laparotomy for acute colic. Pre‐, intra‐ and post operative factors that affected long‐term complications and long‐term survival were assessed. Methods: History, clinical findings, surgical findings and procedures and post operative treatments of 300 consecutive surgical colic cases (1994–2001) were reviewed. Long‐term follow‐up information was retrieved from case records and telephone enquiries from owners. Results: The long‐term (>12 months) survival rate for 204 horses discharged after colic surgery and for which follow‐up information was available was 84%. The most common complication after discharge was colic, affecting 35.1% of horses following a single laparotomy. Colic was most common in horses that had had small intestinal obstructions, bowel resection or post operative ileus. Abdominal adhesions were most common in horses that presented with severe colic due to strangulation of small intestine. Ventral hernia formation occurred in 8% of horses, and was most common in horses that had had post operative wound drainage or infection. Conclusions: This study identified various factors that appear to predispose horses to long‐term complications after colic surgery. Potential relevance: Further evaluation of strategies that might reduce the incidence of such complications are needed; in particular, the value of intraperitoneal heparin should be evaluated, and procedures designed to reduce the rates of wound drainage and infection assessed.

Using an abdominal bandage following an exploratory laparotomy may help reduce the prevalence of post operative incisional complications, and prevent the development of potentially life-threatening complications.