Indicators of 'critical' outcomes in 941 horses seen 'out-of-hours' for colic.

BACKGROUND: This study aimed to describe the presentation and outcomes of horses with signs of colic (abdominal pain) seen 'out-of-hours' in equine practice. METHODS: This was a retrospective study of horses seen 'out-of-hours' with colic by two equine veterinary practices between 2011 and 2013. Case outcomes were categorised as 'critical' or 'not critical'. A critical outcome was defined as requiring medical or surgical hospital treatment, or resulting in euthanasia or death. A non-critical outcome was defined as resolving with simple medical treatment. A hierarchical generalised linear model was used to identify 'red flag' parameters (aspects of signalment, history and presenting clinical signs) associated with critical outcomes. RESULTS: Data were retrieved from 941 cases that presented with colic; 23.9 per cent (n=225/941) were critical. Variables significantly associated with the likelihood of a critical outcome in the final multivariable model were increased heart rate (P<0.001), age of the horse (P=0.013) and abnormal mucous membrane colour (P<0.001). Overall 18 per cent (n=168/941) of cases were euthanased. CONCLUSIONS: This study highlights the mortality associated with colic. The 'red flag' parameters identified should be considered an essential component of the primary assessment of horses with colic.

Exploratory Celiotomy in the Horse Secondary to Acute Colic: A Review of Indications and Success Rates.

To review indications and risk factors for exploratory celiotomy secondary to acute colic in the horse; decision making for and during surgery; and prognosis for return to function after exploratory celiotomy for the practicing veterinarian. Data sources included scientific reviews and original research publications from veterinary sources, as well as clinical data specifically in regard to underlying disease and survival rates from a tertiary referral hospital where exploratory celiotomy is commonly performed. There is a high positive predictive value of specific clinical preoperative parameters of the equine acute abdomen, many of which rely on techniques available to field practitioners, relative to the need for surgical intervention. Decision making regarding surgical procedure or even intraoperative euthanasia depends on owner expectations. Survival rates following exploratory celiotomy range from fair to excellent (60%-100%) depending on underlying lesion and return to athleticism following celiotomy is good to excellent (76%-90%). A knowledge base of indications for and rates of survival from colic requiring exploratory celiotomy in the horse is of paramount importance to the equine practitioner. Preconceived notions of poor survival rates are rampant among horse owners, and owners rely on their primary veterinarian's advice for continuation to referral center and in further treatment including exploratory celiotomy.

Colic in the British military working horse population: a retrospective analysis.

Colic is a common and potentially life-threatening condition of horses. Multiple risk factors have been previously identified and it is known that a careful management routine can help reduce colic rates. The British military working horse population represents a unique cohort of horses that are intensively managed with a strict regimen. This retrospective study examined the incidence and mortality rate of colic within this population, as well as the signalment of affected horses, and compared these with the general population. Data for 717 horses over a five-year period (2008-2012) were analysed. Of these, 163 horses (22.7 per cent) experienced 267 colic episodes and 13 horses (1.8 per cent) died because of colic. Recurrent colic was experienced by 35 per cent (57/163) of horses. The incidence of colic was 11.1 episodes per 100 horse-years and of colic-related death was 0.5 deaths per 100 horse-years. Horses purchased from mainland Europe were more likely to suffer from colic (OR 4.6; P<0.001) and from recurrent colic (OR 6.0; P=0.005) than horses purchased from Ireland. Only 3 per cent (8/267) of colic episodes were treated surgically. It was concluded that the incidences of colic and colic-related deaths within the British military working horse population are similar to those of the general horse population.

Clinical and intestinal histologic features of horses treated for recurrent colic: 66 cases (2006-2015).

OBJECTIVE To describe gastrointestinal histologic findings for horses with recurrent colic and evaluate possible associations between initial clinical signs, biopsy method, histologic diagnosis, and outcome 1 year after hospital discharge. DESIGN Retrospective case series. ANIMALS 66 horses with a history of recurrent colic for which gastrointestinal specimens had been submitted for histologic examination. PROCEDURES Histologic diagnosis was categorized as inflammatory, neoplastic, ischemic, other, and undiagnosed. Relationships among initial clinical features, biopsy method, histologic diagnosis, and outcome 1 year after hospital discharge (ie, alive vs dead and persistent recurrent colic [yes vs no]) and between corticosteroid treatment and outcome were investigated. Odds ratios and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. RESULTS Inflammatory disease (36/66 [55%]) was the most common histologic diagnosis. Horses undergoing rectal biopsy alone were significantly (OR, 14.4; 95% Cl, 2.7 to 76.1) more likely to not have a histologic diagnosis than were horses in which other biopsy methods were used. In multivariable modelling, persistence of recurrent colic (HR, 15.2; 95% Cl, 1.9 to 121.2) and a history of weight loss (HR, 4.9; 95% Cl, 1.4 to 16.5) were significantly associated with outcome (alive vs dead) 1 year after surgery. Corticosteroid treatment was not significantly associated with either outcome. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that a high proportion (36/66 [55%]) of horses with recurrent colic had inflammatory gastrointestinal disease. Use of rectal biopsy alone to obtain biopsy specimens was more likely to result in no histologic diagnosis. Use of corticosteroids in horses with inflammatory gastrointestinal disease was not associated with outcome but warrants further investigation.

Effects of hyaluronate-carboxymethylcellulose membranes on the clinical outcome of horses undergoing emergency exploratory celiotomy.

OBJECTIVE: To determine the influence of hyaluronate-carboxymethylcellulose (HA-CMC) membranes applied to intestinal anastomoses or enterotomies on postoperative complications after emergency exploratory celiotomy. STUDY DESIGN: Multicenter retrospective case-controlled series. ANIMALS: Adult horses (59 in the HA-CMC group and 91 controls). METHODS: Medical records from 4 referral hospitals were searched for horses ≥1 year of age, treated between 2008 and 2014 with emergency exploratory celiotomy, and surviving at least 24 hours postoperatively. Horses receiving repeat celiotomy during the same hospitalization were excluded. Horses who received HA-CMC were matched with controls who did not receive HA-CMC but had similar intestinal lesions and procedures at the same referral hospital. Postoperative complications (colic, nasogastric reflux, fever, incisional infection, and septic peritonitis), duration of hospitalization, and survival were compared between groups. Data were compared between horses by t test, Wilcoxon signed rank test, and χ2 test. RESULTS: The volume of nasogastric reflux at admission (P = .02) and the duration of administration of lidocaine after surgery (P = .02) were greater in horses with HA-CMC membranes than in controls. No difference in postoperative complications or survival was detected between groups: 48 of 59 (81%) horses treated with HA-CMC survived until discharge from the hospital compared with 80 of 91 (88%) horses in the control group (P = .27). Fifteen of 21 horses treated with HA-CMC and 30 of 43 horses in the control group survived >12 months after hospital discharge. CONCLUSION: Application of HA-CMC membranes to anastomoses or intestinal incisions did not influence postoperative complications or survival after emergency celiotomy compared with controls. CLINICAL SIGNIFICANCE: The safety and efficacy of HA-CMC membrane application to intestinal sites during colic surgery in horses is equivocal.

Characteristics of frozen epididymal spermatozoa from stallions that died 12 to 36 hours after colic surgery.

Equine spermatozoa from the cauda epididymis were previously collected and frozen, and the fertility was assessed. Most studies were performed on healthy stallions that had undergone routine castration or on the epididymis collected at the abattoir, but there are no studies on the quality of epididymal semen in subjects which have died from colic or which underwent intensive care. The present study was designed to verify whether a severe illness could affect epididymal semen quality and freezability in the stallion. Therefore, epididymal semen characteristics during the freezing process in stallions which had died from colic and in healthy stallions submitted to elective castration were compared. Five stallions that had died from colic (ill stallions [ISs]) and seven stallions that had undergone elective castration (healthy stallions) were castrated, and cauda epididymis spermatozoa were collected and processed. Sperm quality was tested after collection, after washing procedures, at the end of the equilibration (5 °C for 75 minutes), and after freezing/thawing. Sperm quality was measured by objective motility characteristics, membrane and acrosome integrity, and mitochondrial activity. After collection, sperm in ISs showed low kinetic parameters (total motility: 17.3 ± 3%, progressive motility: 6 ± 1%, average path velocity: 57.4 ± 35.4 µm/s, straightness: 74.2%) compared with healthy stallions (total motility: 90.8 ± 3.7%, progressive motility: 70 ± 4%, average path velocity: 118.1 ± 12.6 µm/s, straightness: 82.4%) but demonstrated similar membrane and acrosome integrity (85 ± 2.8% vs. 87.6 ± 3.1%). Sperm kinetic parameters increased after washing procedures and cooling in ISs, reaching comparable values after equilibration (5 °C for 75 minutes) and freezing/thawing. The data reported in this study suggest that the quality of the equine epididymal spermatozoa cryopreserved in stallions that had died from colic was similar to that reported in epididymal sperm after elective castration and was also similar to the data reported in literature for cryopreserved equine semen.

Association Between Necropsy Evidence of Disseminated Intravascular Coagulation and Hemostatic Variables Before Death in Horses With Colic.

BACKGROUND: Disseminated intravascular coagulation (DIC) is frequent in horses with severe gastrointestinal disorders. Postmortem studies have found fibrin microthrombi in tissues of these horses, but studies relating these histopathological findings with antemortem hemostatic data are lacking. HYPOTHESIS: Antemortem classification of coagulopathy is related to the presence and severity of fibrin deposits observed postmortem in horses with severe gastrointestinal disorders. ANIMALS: Antemortem hemostatic profile data and postmortem tissue samples (kidney, lung, liver) from 48 horses with colic. METHODS: Tissue samples were stained with phosphotungstic acid hematoxylin and immunohistochemical methods for histological examination. A fibrin score (grades 0-4) was assigned for each technique, tissue and horse, as well as the presence or absence of DIC at postmortem examination. D-dimer concentration, prothrombin time (PT), activated partial thromboplastin time (aPTT), and antithrombin (AT) activity, as well as the clinicopathological evidence of coagulopathy, were determined from plasma samples collected 0-24 hours before death or euthanasia. Histologic and clinicopathologic data from the same horses were compared retrospectively. RESULTS: No association was found between antemortem classification of coagulopathy and postmortem diagnosis of DIC based on tissue fibrin deposition. None of the hemostatic parameters was significantly different between horses with or without postmortem diagnosis of DIC. There was no association between horses with fibrin in tissues or different cut-offs for D-dimer concentration and postmortem evidence of DIC. CONCLUSIONS AND CLINICAL IMPORTANCE: Abnormalities of the routine clotting profile, including D-dimer concentration, were not useful in predicting histologic evidence of DIC at necropsy in horses with severe gastrointestinal disorders.

Twenty years later: a single-centre, repeat retrospective analysis of equine perioperative mortality and investigation of recovery quality.

OBJECTIVES: To determine the mortality rates associated with equine anaesthesia for elective and emergency (colic and non-colic) cases in one equine, university teaching hospital and to investigate the effect of several horse- and anaesthetic-related variables on anaesthetic recovery quality. STUDY DESIGN: Retrospective data analysis. ANIMALS OR ANIMAL POPULATION: In total, 1416 horses undergoing anaesthesia between May 2010 and December 2013. METHODS: Patient information and details of the anaesthetic, recovery period and immediate complications were extracted from an archiving database. Statistical evaluation of factors affecting mortality included chi-squared tests and binary logistic regression. Factors affecting recovery quality were investigated using univariable and multivariable ordinal logistic regression. Statistical significance was set at p < 0.05. RESULTS: Anaesthesia/recovery-related mortality was 1.1% for all cases, 0.9% for elective cases, 1.6% for colics and 0% for non-colic emergencies. Fractures and dislocations accounted for the majority (71.4%) of deaths. No intra-operative deaths occurred during the study period. Risk factors for mortality included increasing age and American Society of Anesthesiologist's (ASA) status but these and other factors were confounded by 'colic'. Non-fatal complications in the immediate recovery period included postanaesthetic myopathy/neuropathy and postanaesthetic respiratory obstruction. Recovery quality was associated with body mass (p = 0.016), ASA status 3 and 4 (p = 0.020 and 0.002, respectively), duration of anaesthesia (p < 0.001) and out-of-hours anaesthesia (p = 0.013). Although recovery quality was also influenced by age and breed-type, these factors were removed from the final model as age was highly associated with both ASA status (p < 0.001) and colic surgery (p < 0.001), and breed-type was a determinant of body mass. CONCLUSION AND CLINICAL RELEVANCE: Anaesthetic/recovery-associated mortality was comparable to previously reported figures except intra-operative deaths were not reported. Fractures remained responsible for the largest proportion of recovery-associated deaths. Improvements to the recovery process that can reduce fracture occurrence are still required.

Effects of preoperative administration of hypertonic saline or pentastarch solution on hematologic variables and long-term survival of surgically managed horses with colic.

OBJECTIVE: To compare the effects of preoperatively administered pentastarch (10% concentration in isotonic saline [0.9% NaCl] solution) and hypertonic saline (7.2% NaCl) solutions on PCV and circulating total protein (TP) concentration in horses with colic undergoing emergency exploratory laparotomy and to assess survival rates of horses that received each treatment. DESIGN: Prospective, randomized study. ANIMALS: 100 horses with signs of abdominal pain and PCV ≥ 0.46 L/L. Procedures-Horses received a 4 mL/kg (1.8 mL/lb) dose of pentastarch solution (n = 50) or hypertonic saline solution (50) over a 10- to 20-minute period before anesthetic induction. Blood samples were collected at the time of evaluation and ≤ 5 minutes after fluid resuscitation; changes in PCV and TP concentration were compared. Survival was evaluated by Kaplan-Meier and Cox proportional hazards analyses. RESULTS: Age, weight, sex, PCV, and heart rate on initial examination were similar between treatment groups. Hypertonic saline solution treatment resulted in a significantly greater reduction in PCV (median change, -0.14 L/L) than did pentastarch treatment (median change, -0.07 L/L). Reduction in TP concentration was also significantly greater after hypertonic saline solution treatment (median change, -16 g/L) than after pentastarch treatment (median change, -2 g/L). Long-term survival was not significantly different between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Despite a greater reduction in preanesthetic hemoconcentration following administration of hypertonic saline solution (4 mL/kg infusion, once), no difference in overall long-term survival was found between horses that received this treatment and those that received an equal volume of pentastarch solution. Findings suggested that, in a clinical setting, either of these fluids would be appropriate for preoperative fluid resuscitation in horses with colic.

Surgical treatment of equine colic - a retrospective study of 297 surgeries in Norway 2005-2011.

BACKGROUND: Colic, defined as pain originating from the abdomen, is a common condition in horses. Most of the cases resolve spontaneously or after medical treatment, but a few require surgical treatment. Surgical treatment of colic in horses is resource-demanding and expensive, and information on prognosis is therefore important for both owners and surgeons. In the present study, surgical cases in two equine hospitals in Norway between 2005 and 2011 were reviewed. The aim of the study was to describe associations between prognostic indicators, diagnoses and short term survival by use of random effects logistic regression. RESULTS: In the present study, 162 out of 297 (54.5%) surgeries resulted in the horse being discharged from the hospital. Excluding cases euthanized during surgery, the overall short-term survival was 74.0% (162 out of 219 surgeries). Seventy-eight (26.3%) of the horses were euthanized during surgery, due to grave or poor prognosis. In univariable analyses, duration of colic signs, heart rate, capillary refill time, mucosal membrane appearance, intestinal sounds, affected gastrointestinal segment, hematocrit, intestinal resection, hospital and surgeon board-certification had P-value <0.20 and were assessed in multivariable analyses. Respiration rate, rectal temperature and lactate in blood also had univariable P <0.20, but were left out from multivariable analyses due to too high levels of missing values. A random effect of primary surgeon was included and breed, sex and age were tested in multivariable analyses as possible confounders; and hospital was included to control for hospital routine differences. In the final multivariable model the variables mucosal membrane appearance, affected gastrointestinal segment and surgeon board-certification significantly influenced survival. The random surgeon effect was not significant. CONCLUSIONS: The present study showed that prognostic parameters and diagnoses of surgical treatment of horses with colic in Norway are in accordance with reports from other parts of the world. The significant effect of board-certification of surgeon is not reported in previous studies. The general short-term survival rate was somewhat lower than reported in other studies, partly due to more horses being euthanized intraoperatively in the present study. This might be because of economical or animal welfare reasons.

Short-term survival and mortality rates in a retrospective study of colic in 1588 Danish horses.

BACKGROUND: Outcomes of colic treatment are of great interest to clinicians, horse owners and insurers. One commonly used criterion of success is the overall short-term survival rate. This is used as to compare treatments and to measure quality of veterinary care, but may be biased by demographic or social factors such as attitudes towards animal suffering and euthanasia. The aims of this study were to 1) describe and analyse characteristics in horses with signs of colic referred to the University Hospital for Large Animals (UHLA), University of Copenhagen, Denmark over a 10-year period and 2) to compare these rates with those published in other comparable studies. RESULTS: The overall survival rate for colic horses over the 10-year study period was 68% (confidence intervals (CI): 66-71%; 1087/1588). In the medical group, 1093 horses, short-term survival was 87% (CI: 85-89%). Thirty one % of referred horses were given diagnoses requiring surgical intervention (CI: 29-33%). In this group 32% of the horses were euthanized before surgery (CI: 28-36%; 159/495). Of the surgical cases 27% (CI: 23-31%) were euthanized or died during surgery. Of the horses that recovered from surgery 25% died or were euthanized (CI: 19-32%; 48/189), while 75% survived to discharge (CI: 68-81%). CONCLUSIONS: The short term survival rates of Danish horses with colic were similar or lower to those reported from other countries. Apart from variability of veterinary care, attitudes towards euthanasia vary among the countries, which may bias the outcomes. This study indicates that qualitative interview studies on owners' attitudes towards animal suffering and euthanasia need to be conducted. Our opinion is that survival rates are not valid as sole indicators of quality of care in colic treatment due to selection bias. If the survival rates are to be compared between hospitals, techniques or surgeons, prospective studies including mutually agreed-on disease severity scores and a predefined set of reasons for euthanasia are needed.

Colic in equine neonates: 137 cases (2000-2010).

OBJECTIVE: To document causes of colic in equine neonates, evaluate clinical features of neonates managed medically versus surgically, determine short- and long-term survival rates for neonates with specific medical and surgical lesions, and assess ability of patients to achieve intended use. DESIGN: Retrospective case series. ANIMALS: 137 client-owned equine neonates (< 30 days old) with a history of colic or signs of colic within 1 hour after hospital admission examined between 2000 and 2010. PROCEDURES: Signalment, history, results of physical examination, laboratory data, ancillary diagnostic tests, details of treatment, primary diagnosis, concurrent diseases and short-term survival rate were obtained from the medical records. Long-term follow-up information was obtained through phone survey. RESULTS: 137 neonates with colic were included. The majority (122 [89%]) of neonates were managed medically. The 3 most common diagnoses associated with colic were enterocolitis (37 [27%]), meconium-associated colic (27 [20%]), and transient medical colic (26 [19%]). The most common reason for surgery was small intestinal strangulating obstruction, and these neonates were more likely to have severe, continuous pain and were less responsive to analgesics. Concurrent diseases were common (87 [64%]) but did not significantly impact survival rate. Short-term survival rate was not significantly different between medically (75%) and surgically (73%) managed neonates. Long-term survival rate was excellent (66/71 [93%]) for horses that survived to hospital discharge. Most neonates surviving to maturity were used as intended (49/59 [83%]). CONCLUSIONS AND CLINICAL RELEVANCE: Most neonates examined for signs of colic can be managed medically. Short-term survival rate in medically and surgically treated neonates was good. Long-term survival rate of foals discharged from the hospital was excellent, with most achieving intended use.

Sensitivity and specificity of blood leukocyte counts as an indicator of mortality in horses after colic surgery.

The objectives of this study were to describe and relate perioperative changes in blood leukocyte counts to the outcome of surgical colic horses, determine a cut-off value in the early postoperative period to obtain an indicator of the outcome, and compare the obtained value to a validation population of horses. Fifty-three horses undergoing colic surgery were included in the descriptive part of the study. Total leukocyte counts were performed before, during and serially after surgery. A receiver operating characteristic analysis was performed on the leukocyte counts of 45 of these horses to determine a cut-off value for the outcome. The results obtained were validated on a second set of 50 horses that underwent colic surgery in similar conditions. The kinetics of blood leukocytes in survivors was higher than in non-survivors during the first days. Non-survivor horses were more likely to have at least one blood leukocyte count ≤ 3.9 × 10(3)/mm(3) between 28 and 60 hours after surgery than survivor horses. This cut-off value was confirmed in the validation population. These results suggest that routine values of blood leukocyte counts can be used as an additional prognostic indicator after colic surgery alongside other predictors previously associated with the outcome.

Nephrosplenic entrapment of the large colon in 142 horses (2000-2009): analysis of factors associated with decision of treatment and short-term survival.

REASONS FOR PERFORMING STUDY: Previous studies indicate similar overall survival of horses with nephrosplenic entrapment of the large colon (NSE), regardless of treatment strategy. Short-term survival of a primarily conservative treatment strategy without rolling under general anaesthesia (GA) and a low proportion of surgical intervention as well as indicators of short-term nonsurvival has not been documented. OBJECTIVES: To document short-term survival of horses with NSE treated in a university referral hospital with a low rate of surgical interventions and to determine factors associated with the decision of treatment and short-term nonsurvival. METHODS: A retrospective review of medical records of 142 horses diagnosed with NSE between January 2000 and October 2009 was undertaken. Case details and clinical parameters from the initial examination, treatment and outcome were recorded. Factors associated with decision of treatment and short-term survival were identified by multiple logistic regression analysis. RESULTS: Warmblood breeds were over-represented in comparison to the general colic population. Overall short-term survival was 91.5% (130/142) which is similar to previous studies. Three horses considered to be in need of surgery were subjected to euthanasia for economical reasons before treatment. Of 114 conservatively treated horses, 110 (96.5%) survived, as did 20/25 (80%) of surgically treated horses. Nine conservatively managed horses were treated with phenylephrine. Gastric reflux (P = 0.0077), pain (P = 0.024) and abdominal distension (P = 0.05) were associated with the decision to treat surgically. Increased heart rate (P<0.001), and surgery (P = 0.032) were associated with reduced likelihood of short-term survival. CONCLUSIONS AND POTENTIAL RELEVANCE: Overall short-term survival was similar to that reported in previous studies with higher proportions of surgically managed cases. Consequently, horses with NSE should be managed by a primarily conservative treatment strategy, with the decision to treat surgically based on specific evidence based criteria.

Factors associated with survival of epiploic foramen entrapment colic: a multicentre, international study.

REASONS FOR PERFORMING STUDY: Epiploic foramen entrapment (EFE) has been associated with reduced post operative survival compared to other types of colic but specific factors associated with reduced long-term survival of these cases have not been evaluated in a large number of horses using survival analysis. OBJECTIVE: To describe post operative survival of EFE cases and to identify factors associated with long-term survival. METHODS: A prospective, multicentre, international study was conducted using clinical data and long-term follow-up information for 126 horses diagnosed with EFE during exploratory laparotomy at 15 clinics in the UK, Ireland and USA. Descriptive data were generated and survival analysis performed to identify factors associated with reduced post operative survival. RESULTS: For the EFE cohort that recovered following anaesthesia, survival to hospital discharge was 78.5%. Survival to 1 and 2 years post operatively was 50.6 and 34.3%, respectively. The median survival time of EFE cases undergoing surgery was 397 days. Increased packed cell volume (PCV) and increased length of small intestine (SI) resected were significantly associated with increased likelihood of mortality when multivariable analysis of pre- and intraoperative variables were analysed. When all pre-, intra- and post operative variables were analysed separately, only horses that developed post operative ileus (POI) were shown to be at increased likelihood of mortality. CONCLUSIONS: Increased PCV, increased length of SI resected and POI are all associated with increased likelihood of mortality of EFE cases. This emphasises the importance of early diagnosis and treatment and the need for improved strategies in the management of POI in order to reduce post operative mortality in these cases. POTENTIAL RELEVANCE: The present study provides evidence-based information to clinicians and owners of horses undergoing surgery for EFE about long-term survival. These results are applicable to university and large private clinics over a wide geographical area.

Plasma endotoxin in horses presented to an equine referral hospital: correlation to selected clinical parameters and outcomes.

REASONS FOR PERFORMING STUDY: Endotoxaemia is frequently presumed on the basis of clinical signs in horses with colic. OBJECTIVE: Measurements of plasma endotoxin (LPS) are rarely made in clinical cases and there is little information on the correlations between this variable, clinical variables and outcomes. OBJECTIVES: To measure LPS levels in plasma of horses presented to the Philip Leverhulme Equine Hospital on admission and daily for up to 4 days and to relate LPS levels to selected clinical parameters, such as heart rate and packed cell volume, and outcomes. METHODS: Blood samples were collected and stored at -20°C prior to assay of the plasma using a validated kinetic chromogenic Limulus amoebocyte lysate (LAL) assay. Clinical parameters and outcome variables were collected from hospital records. Associations were determined by Chi-squared test and logistic regression analysis. RESULTS: Daily blood samples were collected from 234 horses. LPS was detected in 26.5% of the study population and in 29% of those horses presented for colic. Horses providing samples with detectable LPS were more likely to die whilst in the hospital than those that did not (P = 0.045). Horses presenting with colic were more likely to have detectable LPS in their plasma than noncolic cases (P = 0.037), although LPS was detected in the plasma of 8 out of 42 noncolic horses. A horse that did not meet the study definition of clinical endotoxaemia was 10 times less likely to provide a positive LPS sample (OR 0.10, 95% CI: 0.05-0.22). CONCLUSIONS: The proportion of horses providing samples with detectable LPS was similar to other studies. POTENTIAL RELEVANCE: LPS was detected in the minority of horses presented with colic. Increased levels of LPS positively correlated with packed cell volume and with risk of mortality in colic cases.

Colic in geriatric compared to mature nongeriatric horses. Part 1: Retrospective review of clinical and laboratory data.

REASON FOR PERFORMING STUDY: It is the impression of some surgeons that geriatric horses have a lower survival rate compared to mature nongeriatric horses following colic surgery. One possible reason for this is that geriatric horses may be more critically ill at admission and have more severe disease than mature nongeriatric horses. OBJECTIVE: To compare admission historical, physical examination and laboratory data for geriatric and mature nongeriatric horses referred for signs of colic. METHODS: Medical records of horses admitted with a presenting complaint of colic between 2000 and 2006 were reviewed. Geriatric horses ≥16 years (n = 300) and mature nongeriatric horses 4-15 years (n = 300). Information obtained included duration of colic prior to admission, admission level of pain, heart rate, intestinal borborygmi, packed cell volume (PCV), plasma creatinine and blood lactate concentrations and peritoneal fluid total protein. Data were analysed using a Chi-squared test or an analysis of variance. Level of significance was P<0.05. RESULTS: There was no difference between geriatric and mature horses in the duration of colic prior to admission or in admission heart rate, PCV, or plasma creatinine or blood lactate concentrations. However, geriatric horses were more likely to be moderately painful and less likely to be bright and alert than mature horses; and less likely to have normal intestinal borborygmi than mature horses. Peritoneal fluid total protein concentration was higher in geriatric than mature horses. CONCLUSIONS AND POTENTIAL RELEVANCE: Geriatric horses presenting with signs of colic had a similar admission cardiovascular status based on heart rate, PCV, and plasma creatinine and blood lactate concentration to mature horses. Geriatric horses, however, may have different causes of colic, which may be more serious than mature horses based on pain, lack of intestinal borborygmi and peritoneal fluid total protein concentration.

Colic in geriatric compared to mature nongeriatric horses. Part 2: Treatment, diagnosis and short-term survival.

REASON FOR PERFORMING STUDY: Owners and veterinarians are often concerned about mortality of geriatric horses following colic surgery. OBJECTIVE: To compare treatment, diagnosis and short-term survival for geriatric compared to mature nongeriatric horses with colic. METHODS: Medical records of horses admitted with a presenting complaint of colic between 2000 and 2006 were reviewed. Geriatric horses were aged ≥16 years (n = 300) and subcategorised as age ≥20 years (n = 134). Mature nongeriatric horses were age 4-15 years (n = 300). Information obtained included medical (included horses subjected to euthanasia without surgery) vs. surgical management, lesion location, type and classification, surgical procedures performed and short-term survival. Data were analysed using a Chi-squared test or an analysis of variance. Level of significance was P<0.05. RESULTS: The overall short-term survival of geriatric horses was lower than that for mature horses (59 vs. 76%, respectively). The survival of medically managed geriatric horses was lower than that for mature horses (58 vs. 80%, respectively). The survival of surgically managed geriatric horses was not different to that for mature horses (59 vs. 70%, respectively) except for geriatric horses age ≥20 years (53%). There was no difference in survival between geriatric and mature horses with small (86 and 83%, respectively) or large (78 vs. 70%, respectively) intestinal strangulating lesions or those undergoing jejunojejunostomy (75 vs. 70%, respectively). Geriatric horses with a large colon simple obstruction had a lower survival compared to mature horses (80 vs. 97%, respectively). CONCLUSIONS AND POTENTIAL RELEVANCE: The survival of geriatric horses with a strangulating lesion or requiring jejunojejunostomy was not different to that for mature horses. Geriatric horses presenting with colic were more likely than mature horses to be subjected to euthanasia without surgery (i.e. lower survival with medical treatment). Geriatric horses undergoing surgery for a large colon simple obstruction had a lower survival than mature horses.

Haemoperitoneum in horses: a retrospective review of 54 cases.

This retrospective study was conducted in the UK and identifies the most frequent causes, diagnoses, treatment and prognoses for short- and long-term survival in 54 cases of horses with haemoperitoneum. Clinical signs of haemorrhagic shock and colic were common, and abdominal ultrasound was very useful for the identification of haemoperitoneum. Causes of haemoperitoneum included uterine injury (22 per cent), involvement of specific blood vessels (20 per cent), splenic injury (19 per cent), neoplasia (13 per cent) and other (4 per cent). No source was identified in 22 per cent of cases. Fifty-seven per cent of cases underwent exploratory laparotomy. Of the surgical cases, a diagnosis was made in 65 per cent, with 42 per cent surviving to discharge. It was felt that exploratory laparotomy had both diagnostic and therapeutic implications. Twenty-eight per cent of cases died, and 33 per cent were euthanased, whereas 39 per cent survived to be discharged from the hospital, with 35 per cent of these surviving in the long term. Idiopathic haemoperitoneum was associated with the best outcome for long-term survival.

Plasma levels of heat shock protein 72 (HSP72) and beta-endorphin as indicators of stress, pain and prognosis in horses with colic.

A prospective observational study was performed to evaluate whether the plasma concentration of heat shock protein 72 (HSP72) or beta-endorphin is related to clinical signs, blood chemistry, or severity of pain of colic. Seventy-seven horses with colic and 15 clinically healthy controls were studied. The horses were divided into four groups which reflected increasing severity of colic, from normal control horses to horses with mild, moderate and severe colic. Blood samples were collected before any treatment. Packed cell volume (PCV) and plasma HSP72, beta-endorphin, cortisol, adrenocorticotropic hormone (ACTH) and lactate concentrations were measured. Plasma beta-endorphin was related with severity of colic and survival, as well as with plasma cortisol, ACTH and lactate concentrations, heart rate, PCV and pain score. High plasma HSP72 concentration may indicate circulatory deficits, but was not associated with clinical signs of colic. Plasma lactate still seemed to be the most useful single prognostic parameter in horses with colic.