Colic Surgery Research Articles

Causes of death in Equidae anaesthetized for procedures other than colic surgery: a comparison with two decades ago

Causes of death in Equidae anaesthetized for procedures other than colic surgery: a comparison with two decades ago

Pelvic flexure enterotomy in the horse: A review of current literature

SummaryEnterotomy of the pelvic flexure is commonly performed during colic surgery in the horse to empty the large colon of its contents. A two‐layer closure with absorbable suture material is recommended, but a consensus has not been established. Many different techniques have been described and tested to evaluate surgical time, luminal diameter reduction, bursting pressure and post‐operative complications including adhesion formation. The results of these studies vary within and between enterotomy techniques. The objective of this narrative review was to evaluate and summarise relevant published literature on pelvic flexure enterotomy techniques in the horse.

Long-term outcome after colic surgery: retrospective study of 106 horses in the USA (2014-2021).

To determine long-term survival rate, defined as survival to 1 year after discharge from the hospital, and rate of return to prior athletic, breeding, or other function in horses undergoing colic surgery at the first presentation at one referral hospital in the Pacific northwest region of the United States. Records were reviewed for all horses that underwent colic surgery between October 2014 and October 2021. Owners of horses that survived to discharge were contacted to obtain follow-up information via internet-based questionnaire or telephone interview. The percentage of horses that survived to 1 year after discharge, rates of return to function, and complications occurring after hospital discharge were determined. The possible association of patient signalment, lesion type, and surgical procedures with long-term survival was examined with Chi-square and Fisher's exact tests. Overall satisfaction was indicated on a scale of 1 (unsatisfied) to 5 (very satisfied). Of 185 horses that underwent surgical intervention for colic and met the inclusion criteria, 134 horses recovered from anesthesia, with 106 of these recovered horses (79.1%) surviving to discharge. Of the 71 horses for which follow-up information was obtained, 61 horses survived to 1 year after discharge (long-term survival rate of 85.9%). There were no demographic, lesion type, or surgical procedure variables significantly associated with long-term survival. Prior to surgery, 59/71 horses (83.1%) were engaged in some type of athletic activity. After surgery, 44/61 horses (72.1%) were reported to be athletically active. Only one horse was reported to be retired from athletic activity as a direct result of a complication from surgery. Overall satisfaction with the decision to proceed with colic surgery was rated by all respondents as 4 or 5. The long-term survival for this sample of horses was similar to previously published reports of long-term survival after colic surgery. Horses that survived to hospital discharge were highly likely to remain alive and be athletically active 1 year later. There were no factors related to the signalment of the horse, the specific cause of colic, or the surgical procedures performed that were significantly associated with likelihood of survival.

Xylazine Infusion during Equine Colic Anesthesia with Isoflurane and Lidocaine: A Retrospective Study.

This retrospective study investigated the effect of a xylazine infusion on heart rate; mean arterial pressure; blood gases; anesthetic and dobutamine requirements; recovery quality and duration; percentage of death/survival; and days to die/discharge in horses after colic surgery under partial intravenous anesthesia with isoflurane and lidocaine infusion. Anesthetic records of equine colic surgery were reviewed from similar periods in 2020-2021 and 2021-2022. In both groups, after sedation with xylazine 0.7 mg/kg intravenously (IV) and induction with ketamine 2.2 mg/kg and midazolam 0.06 mg/kg IV, anesthesia was maintained with isoflurane and lidocaine (bolus 1.5 mg/kg IV, infusion 2 mg/kg/h). Group L (2020-2021, n = 45) received xylazine 0.2 mg/kg IV before recovery, group XL (2021-2022, n = 44) received xylazine 0.5 mg/kg/h IV intraoperatively. In group XL, minimal (p = 0.04) and average (p = 0.04) heart rate, intraoperative hematocrit (p = 0.001), minimal (p = 0.002) and maximal (p = 0.04) dobutamine administration rate, animals requiring ketamine top-ups (p = 0.04), and the number of days to discharge (p = 0.02), were significantly lower compared to group L. During recovery in group XL, the time to sternal recumbency (p = 0.03) and time to first attempt (p = 0.04) were significantly longer. This retrospective study suggests that a xylazine infusion may have beneficial effects on horses undergoing colic surgery. Further prospective studies are necessary.

Incisional complications after skin closure with stainless‐steel skin staples compared to nylon sutures in horses undergoing colic surgery

SummaryBackgroundIncisional complications following ventral midline celiotomy represent a challenge for equine surgeons. Preventative measures to minimise risks of incisional complications are continuously being investigated. This includes the search for an ideal surgical closure method.ObjectiveTo compare the incidence of incisional complications after skin closure with nylon sutures versus stainless‐steel skin staples (SSS) following ventral midline celiotomy for colic surgery in horses and to assess additional risk factors for incisional complications.Study designProspective blinded randomised study (2012–2014).MethodsOne hundred and twenty‐three horses that underwent colic surgery between May 2012 and May 2014 and survived for >2 weeks were included in the study. Horses were allocated randomly to two groups—65 horses were closed with skin staples, and 58 horses were closed with skin sutures (nylon‐0). Patient records and a follow‐up questionnaire were used to record incisional complications that occurred during hospitalisation and after discharge.ResultsFollow‐up information was available in 119 of 123 horses. Four horses without follow‐up were excluded. With strict inclusion criteria, incisional drainage was recorded in 43% (49/115) of the horses, including 40% (25/63) of the surgical staples skin closure group and 46% (24/52) of the nylon suture skin closure group. Pregnancy and large colon intestinal lesions were risk factors for incisional complications. Surgeon 3 was found to decrease the incidence of incisional infection. No association was detected between incisional complications and hernia development.Main limitationsThe non‐uniformity of the follow‐up examination; reliance on owners or caregiver of the horse for follow‐up information, horses lost to follow‐up, incomplete data. Another limitation was the single‐centre design of the study.ConclusionsAlthough not significantly superior, the use of staples may serve as a valid alternative for ventral midline abdominal incision skin closure.

Assessment and comparison of microcirculation and macrocirculation in horses undergoing emergency exploratory celiotomy versus elective surgical procedures.

To assess oral buccal microcirculation by hand-held videomicroscopy in horses during colic surgery, comparing microcirculation values with macrocirculatory parameters and with those of healthy elective surgical horses. Clinical prospective study. Client-owned horses (nine in the colic group; 11 in the elective group). In the colic group, buccal mucosal side stream dark-field microscopy (DFM) videos, cardiac output (CO), mean arterial pressure (MAP), and lactate were obtained at three timepoints under general anesthesia (30, 90, and 150 min after induction). Video analysis was used to determine total vessel density, proportion of perfused vessels, perfused vessel density, and heterogeneity index. Dark-field microscopy videos, MAP, and lactate were obtained at a single timepoint under general anesthesia (45 min after induction) in the elective group. There were no differences in microcirculatory parameters between colic and elective horses, nor was there a difference across timepoints in the colic group. There was a weak negative correlation between microvascular parameters and CO (rho = -0.23). The colic group did not have decreased microcirculation in comparison with the healthy elective group. Dark-field microscopy did not correlate well with macrocirculatory parameters in the colic group. Dark-field microscopy may not be a sensitive enough indicator to detect differences in microcirculation between colic and elective groups. The lack of difference in microcirculation may be due to sample size, probe location, or variation in disease severity.

65 Horse owners’ survey regarding equine feeding management post colic surgery

Nutritional care following colic surgery may be important to help prevent further digestive issues and prolong the life of the equine patients. The objective of this study was to determine how horses are managed nutritionally following colic surgery. Upon approval of the University's Institutional Review Board, an anonymous survey was created using the program Qualtrics that consisted of 15 questions. The survey recorded pre-colic diet, post-colic diet, and any nutritional advice the owner received, both from the surgical clinic and other sources. Respondents also reported the current status of their horse, i.e., retired, deceased, decreased work level, or returned to their previous level of work. A list of all equine colic surgeries performed at the NC State University vet school since 2019 was obtained. The time between surgery and completion of the survey ranged from 6 mo to over 3 years, with the majority (48%) completing it within 2–3 years following the surgery. The survey was sent to a total of 134 horse owners, 27 of which responded for a response rate of 20%. The data collected from the survey was predominantly descriptive in nature. 81% percent of respondents were happy with their horse's overall appearance and performance before the colic episode. At the time of the colic, 26% were feeding a commercial grain mix, 30% werefeeding a low-starch commercial grain mix, 15% were feeding a ration balancer, and 22% were feeding a senior feed. Approximately 48% of the living horses were back to their pre-colic workload at the time of the survey, while 4 horses were deceased. Several owners (21%) reported receiving minimal nutritional instructions at discharge, while others were encouraged to change their horse's hay or pasture (25%), grain (41%) and/or add a supplement (48%). 70% of owners reported gaining nutritional advice from sources outside the surgical clinic, 73% of which spoke with their regular veterinarian, while others consulted friends, online sources, and nutritionists. The majority of supplements implemented by owners were those designed for gastrointestinal health (e.g., probiotics, psyllium, etc.). Many owners received additional nutritional information from outside sources (friends, nutritionist, internet, etc.) or from their regular veterinarian. At the time they completed the survey, 29.6% of respondents reported at least one instance of colic following the horse's discharge. Based on the number of respondents seeking outside advice, the results imply that owners may benefit from additional nutritional resources following surgery.

125 Quantification of chewing frequency in horses consuming bermudagrass hay compared with other popular equine forages

Bermudagrass is the most common fine-stemmed hay forage in the southeastern United State due to its adaptation to this region. The low cost and easy access contribute to bermudagrass hay being commonly fed, consequently it is detected in the digestive tracts of most horses submitted to regional veterinary clinics for impaction colic surgery. A potential association between fine stemmed forages and increased risk of impaction colic may be differences in chewing patterns compared with other hay types. Chewing encourages saliva production which assists in particle size reduction and works as a lubricant, assisting in transit through the gastrointestinal tract. Using 2 studies, the objective of this research was to compare the chewing rate of bermudagrass to other common equine forages. A preliminary 5-week study utilizing 5 privately owned horses routinely fed bermudagrass hay at one feeding and timothy hay at another was conducted to evaluate potential effects of hay type on chewing frequency. Horses were fitted with a RumiWatch® halter (ITIN + HOCH, Switzerland) to quantify chewing patterns and fed their normal amount of hay each feeding. Chewing patterns were continuously monitored until the next meal, and data was reported on a per minute basis. Hay was weighed before feeding, and refused hay was weighed back so the total chews/kg consumed could be calculated. Data were statisticallyanalyzed (Minitab v.21, State College, PA) as a mixed ANOVA with treatment as a fixed effect. Results indicate that horses chewed bermudagrass at a lower frequency compared with timothy (4643 vs. 7461 chews/kg, P = 0.003). At the conclusion of this study, a larger study utilizing 8 horses fed twice daily at 1.5% body weight in forage was conducted to test chewing frequency when eating bermudagrass, alfalfa, ryegrass, and orchardgrass hays. Horses received treatments in a 4 × 4 Latin square design having an acclimation period one week before a 3-d data collection using the RumiWatch® halter. Data were calculated as chews/kg and statistically compared using the same protocol used in the preliminary study. Results indicate that horses chew bermudagrass hay (3649 chews/kg) less as compared orchardgrass (4811 chews/kg), alfalfa (4571 chews/kg), and ryegrass (4763 chews/kg)(P < 0.001). Results further indicate no difference between the minutes chewed for bermudagrass (65.1 min/kg) to alfalfa (73.4 min/kg). However, there are differences between bermudagrass to orchardgrass (76.6 min/kg) and ryegrass (78.7 min/kg P < 0.05) which potentially causes reduction in saliva production and increased risk of impaction colic.

Acute gallbladder disease – The virtue of performing a laparoscopic cholecystectomy in the early stages of case management

Background: In a Benghazi medical center, this observational study assessed the role of laparoscopic cholecystectomy (LC) in the early stages of acute gallbladder illness. Materials and Methods: From January 2022 to December 2022, all emergency and urgent admissions for acute gallbladder disease were identified, and additionally, data from hospital medical records were then evaluated retrospectively. Results: Out of a total of 334 patients with gallstone diseases, we found 321 individuals (206 with acute biliary colic, 115 with acute calculous cholecystitis), and 13 with acalculous cholecystitis. Early laparoscopic surgery for acute calculous cholecystitis had a greater conversion rate than procedures for acute biliary discomfort (19% vs. 4%; p=0.002). When surgery was performed 72 h from the onset of the symptoms for patients with acute calculous cholecystitis, the conversion rate was considerably lower (one out of 25) than when surgery was postponed past 72 h (14 out of 53) or later performed electively (seven out of 23) (p=0.014). In comparison to elective surgery for acute biliary colic (three of 66), elective surgery for prior acute cholecystitis was linked to a higher conversion rate (seven of 22 patients) (p=0.002). Conclusion: LC for acute calculous cholecystitis needs to be done within 72 h of the onset of symptoms, and it is worthwhile.

Short-Term Survival and Postoperative Complications Rates in Horses Undergoing Colic Surgery: A Multicentre Study.

The occurrence of colic could be influenced by the characteristics of a population, geographical area, and feeding management. The aim of this study was to report the short-term postoperative complications and survival rates and to identify factors that might affect the outcome of horses that underwent colic surgery in three Italian surgical referral centres. Data of horses subjected to colic surgery in three referral centres (2018-2021) were analysed. Comparisons of the outcomes were performed using a Mann-Whitney or a Chi square test. Areas under the receiver operating characteristic (ROC) curve and multivariable logistic regression analysis were used for parameters that were significant in the previous univariate analysis. The goodness-of-fit of the model was assessed using the Akike information criterion (AIC). Significance was defined as p < 0.05, and odds ratios and 95% confidence intervals were calculated as percentages. A total of 451 horses were included. The survival rate was 68.5% of all of the horses that underwent colic surgery and 80% of the horses surviving anaesthesia. Age, BCS, PCV and TPP before and after surgery, amount of reflux, type of disease, type of lesion, duration of surgery, surgeon's experience, and amount of intra- and postoperative fluids administered influenced the probability of short-term survival. The multivariate analysis revealed that PCV at arrival, TPP after surgery, and BCS had the highest predictive power. This is the first multicentre study in Italy. The results of this study may help surgeons to inform owners regarding the prognosis of colic surgery.

What do we currently know about incisional complications of colic surgery?

SummaryIt is common for horses to suffer from incisional complications after colic surgery. The complications encountered are oedema, infection, hernia and dehiscence. Oedema is a natural response to surgical trauma but when it is severe it can be associated with additional complications such as infection, hernia and dehiscence. Thus, it is worthwhile preventing marked oedema, and an abdominal bandage is an effective method for that. Infection of the incision is common, but mostly it is mild and does not require significant intervention. Many of the infections manifest after the horse is discharged from the hospital; thus, these infections are markedly underreported. Since multidrug resistance in bacteria are becoming a major problem in equine medicine, sampling the incision for monitoring is important. Hernia formation is typically preceded by incisional infection. Most hernias do not require intervention but some warrant surgical correction. The most simple and effective method to repair them is primary closure of the hernial ring followed by subcutaneous mesh implantation. By this method, one achieves both a strong body wall and a good cosmetic outlook. Complete body wall dehiscence is fortunately uncommon and is often associated with incisional infection and pregnancy. Complete body wall dehiscence usually occurs in about 5 days after surgery and is the most fatal complication. If dehiscence is noticed prior to any evisceration, conservative therapy with close monitoring and a supportive bandage is indicated and has a good chance of success. Once evisceration is noted, emergency secondary body wall closure is indicated, and the prognosis is guarded. To conclude, incisional complications are commonly encountered after colic surgery, most of them have clinically mild implications. Occasionally, these complications may become significant and even fatal. Careful attention to surgical technique and protecting the incision in the immediate post‐operative period can significantly decrease the risk of these complications.

A cross-sectional study of colic and rate of return to racing in Thoroughbreds at Seoul Racecourse in Korea between 2010 and 2020.

The incidence of colic and the outcomes of colic surgery have not been surveyed in racetracks in Korea. This study examined the incidence, mortality, and case fatality of colic and investigated the effects of age and sex after an exploratory celiotomy on the long-term survival rate (return to racing), subsequent racing performance, and career longevity. The incidence, mortality, and case fatalities of colic were examined over an 11-year period. The records of 40 horses that had undergone a celiotomy, after participating in at least one race and 75 race-matched control horses were analyzed. The racing performance and career length of the horses that returned to racing post-surgery were compared with a control group. The annual incidence, fatality rate of colic, and annual mortality rate at Seoul Racecourse were 6.5, 2.8 per 100 horse-years, and 0.2 deaths cases per 100 horse-years, respectively. Of the 40 horses that underwent colic surgery, 26 (65%) returned to racing. The likelihood of returning to racing decreased with increasing age of the horses, and geldings had a lower probability of returning. While the performance in the five preoperative races between the two groups was not significantly different, a significant decrease in racing performance was observed after the surgery date (p < 0.01). Horses that underwent colic surgery did not show a significant decrease in career length. Surgical treatment for colic at the age of three and four years had a negative impact on the racing performance. On the other hand, there was no significant difference in career longevity between the two groups.

A multicenter retrospective case-cohort study on the prevalence of incisional morbidities in late pregnant mares following exploratory celiotomy (2014-2019): 579 cases.

To report the prevalence and risk factors for incisional morbidities in late pregnant and nonpregnant/early pregnant control mares following colic surgery. Multicenter, retrospective, cohort study from January 2014 to December 2019. Two university teaching hospitals and 1 private referral center. Five hundred and seventy-nine fillies and mares ≥2 years old that underwent celiotomy. Pregnant mares (n=54) were >240days in gestation from the last known breeding date and were compared to control females (n=525) undergoing colic surgery. None. Morbidity rates were not different between mare groups with 56% of pregnant mares and 51% of control mares reporting at least 1 morbidity. Incisional swelling was the most common reported complication in both groups. Incisional swelling was associated with shorter hospital stays (odds ratio [OR], 0.18; P<0.01), and drainage was associated with a longer hospital stay (OR, 1.27; P≤0.01) and with use of an abdominal bandage (OR, 4.4; P<0.01). Herniation was associated with hypercapnia under anesthesia (OR, 1.1; P=0.048), previous abdominal surgery (OR, 8.3; P=0.003), and with use of an abdominal bandage (OR, 56; P=0.006). Body wall dehiscence was associated with longer hospital stay (OR, 1.2; P<0.01). Nonsurvival was higher in pregnant mares (13%) compared to control mares (5%; P=0.02). The prevalence of incisional morbidities did not differ between pregnant and control mares undergoing colic surgery. Several factors were associated with incisional morbidities, including the duration of surgery and anesthesia, anesthetic variables, abdominal bandage use, previous ventral abdominal incision, and longer duration of hospitalization.

Risk of anesthesia-related complications in draft horses: a retrospective, single-center analysis

ObjectiveTo report anesthetic-related complications and determine risks associated with anesthesia in draft horses. Study designRetrospective study. AnimalsA total of 401 anesthetic records for draft horse breeds that underwent general anesthesia from January 2010 through December 2020 were reviewed; horses euthanized during general anesthesia were excluded. MethodsDemographics, perioperative drugs used, procedure type and duration, time to extubation, number of attempts to stand, use of sling in recovery and perioperative morbidity and mortality were investigated. Morbidity and mortality statistical evaluation included univariable logistic regression analysis and ordinal regression analysis. ResultsAmerican Society of Anesthesiologists (ASA) status I–II, ASA III–V and total mortality rate for all cases was 0.69% (2/288), 6.19% (7/113) and 2.24% (9/401), respectively, with Belgian horses being overrepresented (6/9). Cardiac arrest occurred in six out of nine horses that died without euthanasia, and five out of six of these horses underwent colic surgery. Factors associated with increased mortality risk included ASA status of III–V, increased body weight, emergency status and horses presenting for colic. Hypotension, hypercarbia and hypoxemia occurred in 56% (224/401), 46% (186/401) and 14% (58/401) of horses, respectively. During recovery from anesthesia, lighter horses and horses undergoing shorter anesthetic procedures were more likely to be successful on the first or second attempt to stand and were less likely to require a sling in recovery. Conclusions and clinical relevanceDraft horses undergoing general anesthesia had a higher mortality rate than previously reported for all types and breeds of horses.

Scoping review: Occurrence and definitions of postoperative complications in equine colic surgery.

Postoperative complications frequently occur following equine colic surgery but there is a lack of consistency in their definitions and reporting. To perform a scoping review to identify current evidence on the definitions and classifications of postoperative complications in equine colic surgery. Evidence review. A scoping review was conducted in CAB, Web of Science, Scopus and PubMed databases using a PCC (Population-equids, Concept-complications, adverse events, sequelae, failure to cure, technical failure, disease progression and Context-postoperative period after colic surgery) search strategy. Peer-reviewed scientific articles in the English language on equine colic surgery in live client-owned equids between 1992 and 2022 were included. The resulting references were independently and blindly screened by two investigators. Relevant data on the study method, sample size, intestinal tract involvement and postoperative complications were extracted and charted. Among 5850 articles potentially eligible, 272 met the final inclusion criteria. The most frequent types of study design were retrospective cohort studies (121/272) and retrospective case series (82/272). Median sample size was 53 animals, range 3-896. Seventy-nine of 272 (29%) studies reported diseases of the small intestine, 65 of 272 (24%) of the large intestine and 128 of 272 (47%) reported both. Seventy-two studies (26.4%) focused on single complications. No study explicitly defined the term complication or cited a classification of complications. One study reported the definitions of 'sequela', 'progression' or 'recurrence' of lesions. Eighty-one postoperative complications were reported in two-time frames defined as short- and long-term. The definitions of most complications and long-term follow-ups were highly variable. Non-English language studies or conference proceedings were excluded. There was a substantial lack of classifications of postoperative complications. The definitions of complications were highly variable, making it difficult to compare studies. Adopting classification systems and definitions may help surgeons to obtain a complete picture of the efficacy of a procedure or treatment and allow comparisons between studies, centres or time periods.

Changes in Perioperative Antimicrobial and Anti-Inflammatory Drugs Regimens for Colic Surgery in Horses: A Single Center Report.

Simple SummaryThe administration of postoperative anti-inflammatory and antimicrobial drugs after colic surgery is based on an empirical approach, and for this reason, in recent years, it has been questioned. Recent guidelines recommend that antimicrobials should be administered for the shortest effective period possible. The use of non-steroidal anti-inflammatory drugs is also discussed given the side effects especially on the gastrointestinal tract. Consequently, the antimicrobial and anti-inflammatory drugs administration in horses has changed in our practice over the years to modulate therapies according to the postoperative complications that eventually arise. The description of these changes and the reasons behind them can help define an appropriate stewardship. Over the years, the administration of postoperative antibiotics has been limited, and treatments have been started only in case of complications that justified their use. As for anti-inflammatories, there was a variation of dosages of flunixin meglumine and the addition of new types of anti-inflammatories, both non-steroidal anti-inflammatory drugs and corticosteroids. These changes in prophylaxis protocols were not associated with an increase in postoperative complications.Reducing postoperative incisional infection is the main reason to administer postoperative antimicrobials (AMD) after emergency laparotomy in horses, while reducing inflammation and providing analgesia are the reasons to administer anti-inflammatory drugs (AID). The basis for postoperative AMD and AID administration is empirical and only recently has been questioned. Empirical approaches can be changed, and these changes, along with the description of their outcomes, can help produce appropriate stewardship. The aim of this study is to report the changes in AMD and AID regimens in horses undergoing emergency laparotomy at a referral teaching hospital between 2017 and 2021. Signalment, pathology, surgery, prophylactic AMD and AID administration were obtained from the medical records. Difference in AMD and AID regimens throughout the study period were also reported. In 234 postoperative records considered, ninety-two horses received prophylactic AMD, while 142 received pre-operative antimicrobials only. There was a progressive change in regimens throughout the years, increasing the number of AID molecules used. AMD and AID administration in horses has changed in our practice over the years to modulate therapies according to the postoperative complications that eventually arise. In this study, horses not receiving postoperative routine AMD treatment did not show an increased incidence of complications.

The role of ERAS nurse for patient motivation after colic surgery

The role of ERAS nurse for patient motivation after colic surgery

Invited Commentary: Advancing the Safety of Laparoscopic Cholecystectomy-Collaboration between Radiologists and Surgeons.

Invited Commentary: Advancing the Safety of Laparoscopic Cholecystectomy-Collaboration between Radiologists and Surgeons.

A survey of non‐steroidal anti‐inflammatory drug use in the post‐operative period following equine colic surgery

SummaryBackgroundThere is currently a lack of evidence surrounding the factors that contribute towards a clinician's decision to discontinue non‐steroidal anti‐inflammatory drug (NSAID) administration during the post‐operative period following equine colic surgery, as well as the drugs and dosages commonly administered to these patients.ObjectivesTo survey clinicians involved in the care of colic patients as to their use of NSAIDs and to investigate the factors associated with the decision to discontinue their administration.Study designAn online questionnaire was created using Jisc Online Surveys, designed to record information about the use of NSAIDs by equine clinicians who regularly manage post‐operative colic patients.MethodsThe questionnaire was distributed to boarded equine veterinarians from the American College of Veterinary Internal Medicine (ACVIM), the European College of Equine Internal Medicine (ECEIM) and the European College of Veterinary Surgeons (ECVS).ResultsResponses were obtained from 60 clinicians. Flunixin and phenylbutazone were the most administered NSAIDs and were also the most widely available drugs. 83% of clinicians ranked the absence of active colic signs as an important factor to consider when deciding the timepoint for NSAID discontinuation following colic surgery, in addition to 81% for pain score evaluation, and 78% for the absence of fever. NSAIDs were typically discontinued 5–7 days post‐operatively in the absence of complications but were often continued for longer where complications occurred.Main limitationsFree text answer boxes provided in the questionnaire meant that some answers were difficult to interpret alongside the rest of the data and, therefore, had to be omitted. The case scenarios were fictitious, potentially altering the clinicians’ treatment decisions compared with real‐life cases, where more clinical information would be available.ConclusionsThere is variation in NSAID usage in the post‐operative colic patient, but agreement among clinicians about which factors are influential when considering NSAID discontinuation.

Performance of predictive models of survival in horses undergoing emergency exploratory laparotomy for colic.

ObjectiveTo evaluate previously published predictive survival models in a population of horses undergoing colic surgery in the midwestern United States.Study designRetrospective cohort study; single referral hospital.AnimalsA total of 260 horses met the inclusion criteria.MethodsMedical records of horses undergoing surgical treatment for colic were reviewed. Previously published models were applied to cohort data to predict outcome. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for prediction of short‐term survival were calculated.ResultsSingle‐variable and multivariable models performed similarly for prediction of survival, with a mean 79% sensitivity (range: 44%–94%), 48% specificity (range: 22%–83%), 63% PPV (range: 56%–72%), 73% NPV (range: 60%–83%), and 64% accuracy (range: 59%–72%). Blood lactate ≤6 mmol/l and the colic severity score (CSS) were highly sensitive for prediction of survival; however, both had poor specificity.ConclusionSingle‐variable and multivariable predictive models did not perform as well for prediction of survival in the study cohort compared to original reports, suggesting that population‐specific factors contribute to patient survival.Clinical significancePredictive models of survival developed in one population may be less reliable when used to predict outcome in horses undergoing colic surgery from an independent population. Additional model testing and refinement using data from multiple surgical centers could be considered to improve prediction of outcome for horses undergoing laparotomy for treatment of colic.