Retrospective evaluation of the effects of a single intraoperative dose of dexamethasone in horses undergoing exploratory laparotomy for small intestinal lesions (2008-2019): 240 cases.

OBJECTIVE: To determine the effect of a single intraoperative dose of dexamethasone on the risk of postoperative reflux (POR) in horses undergoing small intestinal surgery and to investigate its association with incisional complications and short-term survival. DESIGN: Retrospective cohort study over an 11-year period (2008-2019). SETTING: UK-based private referral center. ANIMALS: Two hundred and forty client-owned horses >6 months of age undergoing exploratory laparotomy for treatment of a small intestinal lesion. INTERVENTIONS: Ninety-seven horses received a single intraoperative dose of dexamethasone (0.1 mg/kg, IV). MEASUREMENTS AND MAIN RESULTS: Of 97 horses that received dexamethasone, 52 (53.6%) required small intestinal resection. Of 143 horses that did not receive dexamethasone, small intestinal resection was performed in 78 (54.5%). A total of 70 horses (29%) developed POR. There was no difference in the risk of POR between horses that received dexamethasone (25/97; 26%) and those that did not (45/143; 31%, P = 0.34). Risk factors associated with the development of POR included small intestinal resection (odds ratio [OR]: 4.55, 95% confidence interval [CI]: 2.27-9.11, P < 0.001), a PCV >40% 24 hours postoperatively (OR: 4.11, 95% CI: 2-8.45, P < 0.001), and a WBC count >10 × 109/L on admission (OR: 3.29, 95% CI: 1.47-7.41, P = 0.004). Dexamethasone was not associated with the odds of POR. Horses undergoing repeat laparotomy had a higher risk of incisional infection (OR: 8.07, 95% CI: 1.98-32.81, P = 0.004). Dexamethasone administration was not associated with incisional infection. The development of POR was negatively associated with short-term survival (OR: 0.07, 95% CI: 0.03-0.17, P ≤ 0.001). Dexamethasone administration was not retained in the final multivariable model for survival. CONCLUSIONS: Intraoperative dexamethasone was not associated with the development of POR in this study population, nor did it have an effect on postoperative survival or incisional infection in horses undergoing surgical management of small intestinal disease.

Factors associated with development of post-operative reflux in horses with large colon volvulus and association with complications and outcomes.

BACKGROUND: Post-operative reflux (POR) is rare following large colon volvulus (LCV) but does occur despite the absence of a small intestinal lesion. The prevalence, risk factors and association with survival of POR after LCV are currently unknown. OBJECTIVES: To determine the prevalence of POR in horses with an LCV and its association with survival. A further objective was to assess factors which may predict POR. The hypothesis was that horses with POR following LCV surgery have a worse outcome for survival compared to those without POR. STUDY DESIGN: A retrospective cross-sectional study. METHODS: Clinical data of client owned horses which underwent colic surgery at a single UK referral hospital between 2008 and 2021, where LCV was the primary finding, were retrieved from hospital records. Statistical analyses included chi-squared, t-tests and odds ratios (ORs). Horses with concurrent lesions, and those that did not survive past anaesthetic recovery, were excluded from analysis. POR was defined as ≥2 L of gastric reflux on at least one occasion. RESULTS: A total of 128 horses were included in the study, 23 of which had POR (18%). Overall survival to hospital discharge was 86%, 95% in the non-POR and 44% in the POR group. Horses with POR were less likely to survive to discharge than those without (OR = 26, 95% confidence interval [CI] [7.68-88.0], p < 0.001), and less likely to be alive 3 years after surgery (OR = 13.4, 95% CI [2.78-64.8], p < 0.001). MAIN LIMITATIONS: Due to the retrospective study design, full data sets were not available for every case because clinical records were incomplete or, at that time, certain tests were not performed or clinical variables were not measured. CONCLUSIONS: POR in LCV cases is a negative prognostic indicator for survival.

Use of an equine compression suit to manage a deep axillary wound in a horse.

PURPOSE: To describe the use of an equine compression suit to manage a deep axillary wound in a Thoroughbred filly with bilateral pneumothorax. CASE SUMMARY: A 2-year-old Thoroughbred filly was referred for management of a deep wound to the left axilla. Packing and bandaging of the area were initially attempted, but this became repeatedly dislodged, and bandaging was discontinued. The filly subsequently developed widespread subcutaneous emphysema, and the wound was slow to granulate. Acute onset respiratory distress occurred 11 days after admission, secondary to bilateral worsening pneumothorax, and required placement of a chest drain. A commercially available equine compression suit was then successfully used to hold a primary dressing in place. This resulted in a marked improvement in the subcutaneous emphysema and pneumothorax. Wound granulation subsequently progressed well, and the filly was discharged from the clinic on day 36. UNIQUE INFORMATION PROVIDED: This case report highlights the potential applicability of a compression suit as an alternative to a stent to effectively prevent entry of air and successfully manage axillary wounds in the horse. It was also noted how delayed the progression of a pneumothorax can be after inadequate bandaging of a deep wound in the axillary region. The compression suit provided an alternative means of securing a dressing onto an awkwardly placed wound and may be useful in locations other than the axilla.

Ultrasonographic Assessment of Small Intestinal Motility Following Hyoscine Butylbromide Administration in Horses: A Pilot Study.

Horses commonly receive hyoscine butylbromide (HB) prior to hospital admission for colic. This could alter the appearance of the small intestine (SI) on ultrasound scan and affect clinical decision making. The aim of this study was to assess the impact of HB on ultrasonographically assessed SI motility and heart rate. Six horses hospitalised for medical colic with no significant abnormalities on baseline abdominal ultrasound examination were included. Ultrasound was performed in three locations (right inguinal, left inguinal and hepatoduodenal window) before and at 1, 5, 15, 30, 45, 60, 90, and 120 minutes after intravenous injection of 0.3 mg/kg HB. Three blinded reviewers assessed SI motility using a subjective grading scale from 1 to 4, one being normal motility and four being no motility. Moderate interindividual and interobserver variability was observed, but none of the included horses developed dilated turgid loops of SI. Hyoscine butylbromide did not significantly reduce SI motility grade in any location (P = .60 left inguinal, P = .16 right inguinal, P = .09 duodenum). Heart rate (mean ± SD) was 33 ± 3 prior to HB injection and peaked at 71.3 ± 9 one-minute postinjection. Heart rate was significantly increased until 45 minutes (48 ± 9) after HB administration (P = .04). The appearance of dilated turgid SI loops common with strangulating intestinal lesions did not appear to develop following HB administration. Hyoscine butylbromide administered shortly before abdominal ultrasound examination would not be expected to affect clinical decision making in horses without small intestinal disease.

Adapted tissue assay for the assessment of ileal granulocyte degranulation following in ovo inoculation with select bacteria or coccidial challenge in chickens.

A previously described heterophil degranulation assay was adapted for use with ileal mucosal tissue via quantification of ß-D-glucuronidase and assay end product 4-methylumbelliferone (4-MU). Three initial experiments evaluated the effect of in ovo inoculations of Citrobacter freundii (CF) or mixed lactic acid bacteria (LAB) on ileal granulocyte degranulation. Inoculations were administered on embryonic d18, body weights (BW) were recorded on day of hatch (DOH) and d10 to calculate body weight gain (BWG), and ileal mucosal scrapings were collected on DOH or d10 for the 4-MU assay. In all experiments, treatments were statistically analyzed relative to control groups. Treatments minimally affected BWG in all in ovo experiments (p > 0.05) relative to respective control groups. Similarly, ileal degranulation in in ovo treatments did not statistically differ (p > 0.05). Based on BWG, in ovo treatments may have induced low-level inflammation unable to elicit detectable changes via the 4-MU assay. Four subsequent experiments were conducted to evaluate effects of Eimeria maxima (EM) on ileal degranulation. Treatments included non-inoculated controls and low, medium, or high EM infection. Across all four experiments, final BW or BWG over the inoculation period were suppressed (p < 0.05) in EM groups relative to respective controls with the exception of EM-low (p = 0.094) and EM-medium (p = 0.096) in one trial. Ileal mucosal scrapings for the 4-MU assay were collected on day of peak lesions. Resulting values were reduced (p < 0.05) for EM treated birds in three experiments with the exception of EM-medium (p = 0.247). No differences were observed in one experiment (p = 0.351), which may have been attributed to a variation in strain of infecting Eimeria. Although refinement for low level inflammation is warranted, results indicate successful adaptation of the 4-MU assay for use with intestinal tissue during significant gastrointestinal inflammation.

Outcome following emergency laparotomy in 33 UK donkeys: A retrospective multicentre study.

BACKGROUND: Emergency laparotomies in donkeys are infrequently performed and there is limited literature on the subject. OBJECTIVES: To determine findings and associated outcomes of exploratory laparotomies in donkeys. STUDY DESIGN: Descriptive retrospective study. METHODS: Donkeys undergoing emergency exploratory laparotomy for investigation and treatment of colic at seven UK referral hospitals between 2005-2017 were included. Data were retrieved from available hospital records. Descriptive statistics and inferential statistical analysis of outcomes of interest was performed in three steps. RESULTS: Thirty-three cases fulfilled the inclusion criteria. Clinical signs on presentation were available for 32 donkeys, of which 53.1% (17/32) presented for investigation of colic while in 46.9% (15/32) the presenting complaint was non-specific. Primary lesion location included small intestine (42.4%, 14/33), large colon (39.3%, 13/33), caecum (6.1%, 2/33), stomach (6.1%, 2/33) and 6.1% (2/33) had multiple abnormal findings without a clear primary lesion. Overall survival to discharge was 54.5% (18/33). Five donkeys (15.2%, 5/33) were euthanased at surgery and of those recovering from general anaesthesia a further 35.7% (10/28) were euthanased or died prior to discharge. Six donkeys (21.4%, 6/28) required a second laparotomy of which 4 (66.7%, 4/6) survived. Post-operative complications occurred in 82.1% (23/28) of cases and included hyperlipaemia (42.9%, 12/28), incisional complications (21.4%, 6/28), ileus (21.4%, 6/28) and persistent colic (17.9%, 5/28). When adjusted for other complications, donkeys with primary gastric lesions were less likely to have presented with severe colic compared with those with primary small intestinal lesions (OR: 0.07, 95% CI 0.01-0.95, p = 0.05). Only age was positively associated with death prior to discharge (OR: 1.18, 95% CI 1.03-1.36, p = 0.02). MAIN LIMITATIONS: Small sample size and retrospective design. CONCLUSION: Donkeys with abdominal lesions may present with a range of signs often not including colic. Surgical findings were diverse and survival to discharge appears to be lower than in horses.

Caecal dysfunction following standing surgical procedures.

The aim of this study is to report cases of caecal dysfunction following surgical procedures in the standing horse. The study design is retrospective. Six client-owned horses developed caecal dysfunction following a variety of surgical procedures undertaken in the standing sedated horse. Medical records were reviewed for caecal dysfunctions that had occurred in horses within 2 weeks of standing surgical procedures. Signalment, details of the original standing surgery and medications administered were recorded. Short-term outcome was obtained from clinical records. Long-term outcome was obtained by telephone questionnaire with the owner. Six horses were identified to have developed caecal dysfunction following standing surgery for tooth extraction, laparoscopic ovariectomy, laparoscopic cryptorchidectomy, fracture repair, melanoma removal and castration. Three horses were euthanised with caecal perforation at the time of diagnosis. Three underwent surgical treatment (typhlotomy, decompression and caecal bypass by ileocolostomy). All three horses were alive post-operatively (follow-up at 2, 12 and 24 months). Caecal dysfunction may develop following surgical procedures performed under standing sedation. Careful post-operative monitoring and early identification of caecal dysfunction, and consequent potential need for surgical intervention, are important to optimise outcomes and minimise the risk of fatal caecal perforation occurring.

Umbilical Cord Herniation With Small Intestinal Evisceration in Two Thoroughbred Neonates.

This report describes two cases of spontaneous small intestinal evisceration via normally inserted umbilical stumps, without abdominal wall trauma. Both cases occurred immediately following uneventful parturition. The authors believe that these represent cases of umbilical cord herniation. This is a well-recognised condition in humans, but has not been previously described in equines. One foal died before veterinary intervention. The second foal underwent a jejunal resection with end-to-end anastomosis and survived to successfully race. This report describes a previously unrecognised condition and highlights the importance of rapid and appropriate intervention on farm.

Serum symmetric dimethylarginine concentration in healthy neonatal Thoroughbred foals.

BACKGROUND: Symmetric dimethylarginine (SDMA) is widely used in other species as a marker of renal dysfunction and is considered a more sensitive indicator of glomerular filtration rate than creatinine. Reference ranges are established in healthy adult horses (≤14 µg/dL) and concentrations are increased in horses with acute kidney injury (median 32 µg/dL; range 15-92). OBJECTIVES: To establish the normal range of SDMA concentrations in neonatal Thoroughbreds. STUDY DESIGN: Cross-sectional. METHODS: Blood samples were collected from Thoroughbred foals <36 h old deemed healthy by physical examination. Exclusion criteria included foals from mares undergoing treatment for placentitis and foals that developed clinical disease or died/euthanised <2 weeks from birth. Biochemistry and serum SDMA concentrations were obtained. RESULTS: Subjects included 120 foals. Median age was 13.5 h (range 1.0-34.0). Median and 95% confidence interval for SDMA concentration was 69.0 µg/dL (63.0, 75.0; range 35.0-376.0). A cut-off value of 168 µg/dL would include 95% of individuals and is therefore suggested. Serum SDMA concentration was correlated with age (R = -.3, P = .003), creatinine concentration (R = .6, P ≤ .001) and urea concentration (R = .3, P = .002). MAIN LIMITATIONS: Limitations include a small sample size, no consideration of subclinical disease and a short follow-up period. CONCLUSIONS: In equine neonates, SDMA concentration is higher than in adult horses, older foals and adults with acute kidney injury. Therefore, currently SDMA cannot be used as a marker of renal dysfunction in this age group. Further work is required to assess whether SDMA concentration is increased in neonates with renal disease and, if so, what cut-off should be used.

Intrasynovial triamcinolone treatment is not associated with incidence of acute laminitis.

BACKGROUND: Intrasynovial corticosteroid injections are commonly used in the treatment of equine orthopaedic disease, but corticosteroid administration is widely considered a risk factor for the development of laminitis. Despite a list of putative mechanisms and a number of case reports of steroid-induced laminitis, no case-control or cohort studies investigating the association between use of intrasynovial corticosteroids and acute laminitis have been published. OBJECTIVES: To quantify the risk of laminitis posed by intrasynovial triamcinolone acetonide (TA) administration in a mixed population of horses. STUDY DESIGN: Retrospective observational cohort study. METHODS: Clinical records of horses registered with one large UK equine practice were reviewed retrospectively to identify all horses receiving intrasynovial TA treatment between 1 January 2007 and 31 December 2017. A total of 1510 horses were selected and records investigated for incidence of laminitis over a 4-month period following treatment. For each TA-treated horse, an untreated horse, individually matched by age, sex, date of treatment and client type, was selected from the clinical records. Untreated horses were then investigated for laminitis over the same 4-month period. Data were analysed in a 2 × 2 contingency table using Fisher's exact test. RESULTS: A total of 489 horses were lost to follow-up and 55 horses were excluded, leaving 966 treated and matched, untreated horses. The incidence of laminitis over the 4-month study period in both groups was identical: 3/966 horses (0.31%) (95% C.I. [0.08%, 0.91%]), equivalent to 0.93 cases per 100 horses per year (P > .9). MAIN LIMITATIONS: Retrospective study; large proportion (489/1510) of horses lost to follow-up; large proportion of study population were racehorses; selection method resulted in disproportionate selection of horses born before 2013; similar incidence between groups may reflect existing risk-based selection by clinicians. CONCLUSIONS: intrasynovial triamcinolone acetonide administration does not increase the risk of laminitis in this study population.

Assessment of acute moderate hyperglycemia on traditional and thromboelastometry coagulation parameters in healthy adult horses.

OBJECTIVE: To determine whether experimentally induced acute moderate hyperglycemia is associated with coagulation activation in healthy adult horses. DESIGN: Prospective experimental study. SETTING: University veterinary teaching hospital. ANIMALS: Six healthy adult horses. INTERVENTIONS: Hyperglycemia (10.0-13.3 mmol/L [180-240 mg/dL]) was induced and maintained for 6 hours using a hyperglycemic clamp technique. Blood glucose concentrations were assessed using a point of care (POC) glucometer at 10- and 20-minute intervals throughout the hyperglycemic clamp procedure. Platelet count, fibrinogen concentration, prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin antithrombin complex level (TAT), and thromboelastometry (TEM) were determined before and after jugular catheter placement, prior to glucose administration, and at 3 and 6 hours of sustained hyperglycemia. Data were analyzed by repeated measures analysis of variance with significance defined as P < 0.05. MEASUREMENTS AND MAIN RESULTS: All horses maintained blood glucose concentration >10.0 mmol/L (>180 mg/dL) throughout the duration of the hyperglycemic clamp with a mean concentration of 11.9 ± 0.3 mmol/L [216 ± 6 mg/dL] as measured by the POC glucometer. No significant difference was found for any evaluated parameter associated with sustained hyperglycemia. Intravenous catheter placement resulted in a significant increase in mean TAT (0.8 ± 0.3 µg/L pre-catheter, 2.3 ± 0.8 µg/L post-catheter; P = 0.008). CONCLUSIONS: Acute, moderate hyperglycemia in healthy adult horses does not have a detectable effect on coagulation based on evaluated parameters. Jugular catheter placement results in a transient increase in thrombin generation as determined by increased TAT concentrations.

Attempted medical management of suspected ascending colon displacement in horses.

OBJECTIVE: To determine the success of medical management of suspected displacement of the ascending (large) colon in horses. STUDY DESIGN: Retrospective case series. ANIMALS: Horses (n = 127) with suspected large colon displacement. METHODS: Medical records (January 1998-September 2008) of horses admitted for colic were reviewed. Suspected large colon displacement was diagnosed from clinical examination and in some cases, subsequent surgical examination. Medically managed horses were exercised and administered intravenous fluids and analgesia. Horses with suspected left dorsal displacement (LDD) of the large colon were also administered phenylephrine. RESULTS: Medical management had a high success rate for treatment of suspected right dorsal displacement (RDD) (64%) and LDD (76%) of the large colon; 4 horses died (1) or were euthanatized (3) and 36 horses had surgery. Of 127 horses treated medically or surgically for a colon displacement, 94% survived to hospital discharge. CONCLUSIONS: Horses with suspected RDD or LDD of the large colon may respond to medical management including exercise.

Osteomyelitis and osteonecrosis after intraosseous perfusion with gentamicin.

OBJECTIVE: To describe and discuss previously unreported complications associated with intraosseous perfusion with gentamicin in horses. STUDY DESIGN: Case report. ANIMALS: Ten-year-old Warmblood gelding. METHODS: Intraosseous perfusion with gentamicin into the proximal phalanx (P1) was used as part of the treatment regimen for distal interphalangeal joint and navicular bursa synovial sepsis. Although the sepsis responded favorably complications developed at the perfusion site, including persistent osteomyelitis, progressive osteonecrosis, and ultimately pathologic fracture of P1. RESULTS: The progression of the clinical signs and findings at necropsy are suggestive of a toxic osteonecrosis secondary to intraosseous perfusion. CONCLUSIONS: Further work is needed to investigate the effects of high dose gentamicin on equine mesenchymal cells that may be achieved during intraosseous perfusion. CLINICAL RELEVANCE: Lower doses of perfusate within the medullary canal of P1 or alternative perfusion sites should be considered.

Clinical nurse specialists' knowledge specific to Medicare structures and processes.

PURPOSE: The purpose of this study was to describe clinical nurse specialists' (CNSs) knowledge of Medicare structures and processes using a multiple-choice examination. DESIGN: This descriptive study used the survey method with a convenient sample. SETTING: Potential subjects received the research study packet at the address designated by them for membership mailings sent from the National Association of Clinical Nurse Specialists (NACNS). SAMPLE: The population of interest was practicing CNSs. The accessible population was NACNS members drawn from the 2002 mailing list organized by zip code. Every third mailing label was skipped. The remaining list members (N = 950) received a study packet. There was a 14.42% response rate with 137 respondents. Eighty-two percent held a master's degree in nursing. METHODS: A 46 item multiple-choice examination was developed based upon a content map established after a review of the available Medicare-related literature and consultation with Medicare advanced practice nurse providers. Content validity was established. Survey packets with the instrument, Scantron answer key, informational letter, and demographic profile were sent to potential subjects. Returned responses were keyed for correct answers. Relationships between demographic variables, raw score, and self-reported Medicare expertise were analyzed. Qualitative data elicited on the demographic form were thematically analyzed. FINDINGS: The examination had a.67 coefficient. Correlation of examination raw score to self-reported Medicare content expertise was 0.982 (P =.000). One third of the examination questions were incorrectly answered by 30% or more of respondents. Percentage correct scores ranged from 60.9 to 95.7 (M = 62.7%; SD = 10.46). Respondents offered 40 comments. Eleven comments related to a self-recognized Medicare knowledge deficit. Four responses highlighted that graduate studies had not provided them with the knowledge necessary for understanding reimbursement issues. Ten respondents expressed an interest in locating some type of educational resource addressing the Medicare system, reimbursement processes, and opportunities. CONCLUSIONS: Findings suggest that NACNS members have Medicare program knowledge deficits. Respondents recognize their deficiencies and are interested in obtaining more information about Medicare but are uncertain as to available resources or networking opportunities that might support them in this process. Graduate nursing programs may need to evaluate the amount of information provided within curriculums specific to insurance reimbursement and Medicare structures and processes. Study limitations include the low response rate and indeterminate sample representativeness. IMPLICATIONS FOR PRACTICE: Educators should examine CNS curriculums to ensure the adequacy of Medicare program information. Continuing education programs and conference workshops addressing Medicare information should be offered to CNSs interested in increasing their expertise or exploring provider opportunities. There may be entrepreneurial opportunities available to CNSs interested in developing an expertise in Medicare programs. Future research studies should quantify potential benefits to Medicare beneficiaries when CNSs participate as providers.