Pre-operative feeding effects on post-anaesthetic colic and faecal output in horses.
Abstract: Post-anaesthetic colic (PAC) is a complication in horses undergoing general anaesthesia (GA). Various preoperative feeding strategies are used in equine practice, yet their impact on PAC remains unclear. Objective: To identify perioperative risk factors associated with PAC and evaluate the influence of preoperative fasting on PAC prevalence and faecal output. Methods: Retrospective cohort study. Methods: Medical records of horses undergoing non-abdominal surgery under GA were reviewed. Horses were categorised into fasted and non-fasted groups based on their pre-anaesthetic feeding regimen. Multivariable logistic regression was used to identify variables associated with PAC. Differences in faecal output and water intake between groups were analysed using a two-tailed hypothesis test. Results: A total of 620 cases were included. Fasting (odds ratio [OR] 2.7, 95% CI 1.4-5.5, p = 0.005), increased surgery duration (per minute) (OR 1.01, 95% CI 1.002-1.02, p = 0.017) and increasing age (OR 1.08, 95% CI 1.02-1.15, p = 0.012) were significantly associated with PAC. Non-fasted horses passed significantly more manure post-operatively. Median (IQR) manure production per hour was 0.44 (0.31-0.61) piles in non-fasted versus 0.38 (0.25-0.50) piles in fasted horses during the first 24 h post-anaesthesia (p < 0.001) and 0.53 (0.42-0.67) versus 0.50 (0.36-0.63) in the second 24 h post-anaesthesia (p = 0.04). Water intake 12 h pre-anaesthesia was also higher in non-fasted horses (1.02 [0.73-1.75] L/h) compared to fasted horses (0.88 [0.53-1.75] L/h; p < 0.001). Conclusions: Poor overall accuracy of the predictive model obtained. The retrospective design of the study may introduce bias due to possible inconsistencies in medical records. Conclusions: Pre-operative fasting was associated with increased risk of PAC and reduced faecal output in horses. These findings support reconsidering fasting practices in equine anaesthesia.
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Publication Date: 2025-10-01 PubMed ID: 41032053DOI: 10.1111/evj.70100Google Scholar: Lookup
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- Journal Article
Summary
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Overview
- This study investigated how preoperative feeding affects the likelihood of post-anaesthetic colic (PAC) and fecal output in horses undergoing general anaesthesia for non-abdominal surgeries.
- The research analyzed medical records to determine if fasting before anesthesia increased PAC risk and altered postoperative manure production and water intake.
Background
- Post-anaesthetic colic (PAC) is a known complication in horses following general anaesthesia (GA), leading to discomfort and potential health risks.
- In equine practice, different preoperative feeding protocols are implemented, including fasting periods, but the effect of these practices on PAC is not well defined.
Research Objectives
- Identify perioperative risk factors associated with PAC in horses undergoing GA for non-abdominal surgeries.
- Evaluate the influence of preoperative fasting on the prevalence of PAC and fecal output post-surgery.
Methods
- A retrospective cohort study was conducted by reviewing medical records of 620 horses that underwent non-abdominal surgeries under GA.
- Horses were divided into two groups based on their pre-anaesthetic feeding regimen: fasted and non-fasted.
- Logistic regression analysis was used to identify variables significantly associated with PAC.
- Differences in fecal output (manure piles per hour) and water intake 12 hours prior to anaesthesia were analyzed between groups using two-tailed hypothesis tests.
Key Findings
- Fasting significantly increased the odds of developing PAC:
- Odds ratio (OR) of 2.7 indicating fasted horses were approximately 2.7 times more likely to experience PAC compared to non-fasted horses.
- Confidence interval (95% CI) ranged between 1.4 and 5.5, and the p-value was statistically significant at 0.005.
- Longer surgery duration was also associated with a slight increase in PAC risk (OR 1.01 per minute).
- Older horses had a higher likelihood of PAC (OR 1.08 per year increase in age).
- Non-fasted horses produced significantly more manure postoperatively:
- During the first 24 hours post-anaesthesia, non-fasted horses produced a median of 0.44 manure piles per hour compared to 0.38 in fasted horses (p < 0.001).
- During the second 24 hours, non-fasted horses produced 0.53 piles per hour versus 0.50 in fasted horses (p = 0.04).
- Water intake 12 hours before anaesthesia was higher in non-fasted horses (median 1.02 L/h) than in fasted horses (0.88 L/h), with p < 0.001.
Implications and Conclusions
- The study suggests that preoperative fasting increases the risk of PAC and reduces postoperative fecal output in horses undergoing GA.
- Non-fasted horses had better hydration levels pre-anaesthesia, which may contribute to improved gut motility after surgery.
- Despite significant associations found, the researchers noted the overall predictive model was of poor accuracy for individual prediction.
- Retrospective study design limitations were acknowledged, including possible inconsistencies and bias in medical records that might affect results.
- Findings support reconsidering standard fasting practices in equine anaesthesia to potentially reduce PAC occurrence and promote better postoperative digestive function.
Cite This Article
APA
Lopes A, Aitkin E, Louro LF.
(2025).
Pre-operative feeding effects on post-anaesthetic colic and faecal output in horses.
Equine Vet J.
https://doi.org/10.1111/evj.70100 Publication
Researcher Affiliations
- Liphook Equine Hospital, Liphook, Hampshire, UK.
- Liphook Equine Hospital, Liphook, Hampshire, UK.
- School of Veterinary Science, Leahurst Campus, University of Liverpool, Neston, Cheshire, UK.
References
This article includes 28 references
- Jago RC, Corletto F, Wright IM. Peri‐anaesthetic complications in an equine referral hospital: risk factors for post anaesthetic colic. Equine Vet J 2015;47(6):635–640.
- Andersen MS, Clark L, Dyson SJ, Newton JR. Risk factors for colic in horses after general anaesthesia for MRI or nonabdominal surgery: absence of evidence of effect from perianaesthetic morphine. Equine Vet J 2010;38(4):368–374.
- Bailey PA, Hague BA, Davis M, Major MD, Zubrod CJ, Brakenhoff JE. Incidence of post‐anesthetic colic in non‐fasted adult equine patients. Can Vet J Rev Vet Can 2016;57(12):1263–1266.
- Senior JM, Pinchbeck GL, Dugdale AHA, Clegg PD. Retrospective study the risk factors and prevalence of colic in horses after orthopaedic surgery. Vet Rec 2004;155(11):321–325.
- Nelson BB, Lordan EE, Hassel DM. Risk factors associated with gastrointestinal dysfunction in horses undergoing elective procedures under general anaesthesia. Equine Vet J 2013;45(S45):8–14.
- Little D, Redding WR, Blikslager AT. Risk factors for reduced postoperative fecal output in horses: 37 cases (1997–1998). J Am Vet Med Assoc 2001;218(3):414–420.
- Jones RS, Edwards GB, Brearley JC. Commentary on prolonged starvation as a factor associated with post operative colic. Equine Vet Educ 1991;3(1):16–18.
- Barton CK, Hector RC, Hendrickson DA, Kawcak CE, Nelson BB, Goodrich LR. Fasting horses perioperatively decreases manure production and increases time to manure output postoperatively: a controlled randomized trial. J Am Vet Med Assoc 2024;262(9):1201–1208.
- Haralambus R, Juri M, Mokry A, Jenner F. The impact of opioid administration on the incidence of postanaesthetic colic in horses. Front Pain Res 2024;5:1347548.
- Krueger CR, Hackett ES, Hess AM, Mama KR. Evaluation of the element point‐of‐care blood gas analyzer for use in horses. J Vet Emerg Crit Care 2020;30(3):279–285.
- Schober P, Boer C, Schwarte LA. Correlation coefficients: appropriate use and interpretation. Anesth Analg 2018;126(5):1763–1768.
- Hosmer DW, Lemeshow S, Sturdivant RX. Applied logistic regression. 1st ed. Hoboken, NJ: Wiley; 2013.
- Mitchell CF, Malone ED, Sage AM, Niksich K. Evaluation of gastrointestinal activity patterns in healthy horses using B mode and Doppler ultrasonography. Can Vet J Rev Vet Can 2005;46(2):134–140.
- VanderBroek AR, Reef VB, Aitken MR, Stefanovski D, Southwood LL. Assessing gastrointestinal motility in healthy horses comparing auscultation, ultrasonography and an acoustic gastrointestinal surveillance biosensor: a randomised, blinded, controlled crossover proof of principle study. Equine Vet J 2019;51(2):246–251.
- Merkies K, Ready C, Farkas L, Hodder A. Eye blink rates and eyelid twitches as a non‐invasive measure of stress in the domestic horse. Animals 2019;9(8):562.
- Taché Y, Million M. Role of corticotropin‐releasing factor signaling in stress‐related alterations of colonic motility and hyperalgesia. J Neurogastroenterol Motil 2015;21(1):8–24.
- Freeman DE, Mooney A, Giguère S, Claire J, Evetts C, Diskant P. Effect of feed deprivation on daily water consumption in healthy horses. Equine Vet J 2021;53(1):117–124.
- Williams S, Horner J, Orton E, Green M, McMullen S, Mobasheri A. Water intake, faecal output and intestinal motility in horses moved from pasture to a stabled management regime with controlled exercise. Equine Vet J 2015;47(1):96–100.
- Brady MC, Kinn S, Stuart P, Ness V. Preoperative fasting for adults to prevent perioperative complications. Cochrane Database Syst Rev 2003;(4):CD004423.
- Savvas I, Rallis T, Raptopoulos D. The effect of pre‐anaesthetic fasting time and type of food on gastric content volume and acidity in dogs. Vet Anaesth Analg 2009;36(6):539–546.
- Tsompanidou P, Robben JH, Savvas I, Anagnostou T, Prassinos NN, Kazakos GM. The effect of the preoperative fasting regimen on the incidence of gastro‐oesophageal reflux in 90 dogs. Animals 2021;12(1):64.
- Sanchez LC. Disorders of the gastrointestinal system. 2018;p. 796.
- Ribonnet C, Palmers K, Saegerman C, Vanderperren K, Van Galen G. Perioperative lung ultrasonography in healthy horses undergoing general anesthesia for elective surgery. J Vet Intern Med 2022;36(3):1160–1172.
- Monticelli P, Adami C. Aspiration pneumonitis (Mendelson's syndrome) as perianaesthetic complication occurring in two horses: a case report. Equine Vet Educ 2019;31(4):183–187.
- Rainger J, Hughes K, Kessell A, Dart C. Pleuropneumonia as a sequela of myelography and general anaesthesia in a Thoroughbred colt. Aust Vet J 2006;84(4):138–142.
- Elfenbein JR, Robertson SA, MacKay RJ, KuKanich B, Sanchez LC. Systemic and anti‐nociceptive effects of prolonged lidocaine, ketamine, and butorphanol infusions alone and in combination in healthy horses. BMC Vet Res 2014;10(S1):S6.
- Dobromylskyj P, Taylor PM, Brearley JC, Johnson CB, Luna SPL. Effect of pre‐operative starvation on intra‐operative arterial oxygen tension in horses. J Vet Anaesth 1996;23(2):75–77.
- Johnston G, Eastment J, Wood J, Taylor P. The confidential enquiry into perioperative equine fatalities (CEPEF): mortality results of Phases 1 and 2. Vet Anaesth Analg 2002;29(4):159–170.
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