The influence of the full moon on the number of accessions to an animal emergency centre

OBJECTIVE: To test the hypothesis that the number of animal emergency centre accessions is associated with the time of the full moon. DESIGN AND PROCEDURE: Retrospective study. A comparison was made of the number of accessions to the University of Melbourne Animal Emergency Centre in the period February 2003 to January 2006 on full moon and non-full moon days, adjusted for day of the week and public holiday. A three day period with the day of the full moon as the middle day was taken to be a full moon period. RESULTS: A total of 12,102 animals were presented to the Centre in this time. An adjusted count ratio of 1.048 (95% CI 0.97 to 1.14; P = 0.26) for accessions on full moon days compared with those on non-full moon days indicated that there was no significant association between the full moon and the number of accessions per day. CONCLUSION: There was no significant difference between the number of animals presented to the University of Melbourne Animal Emergency Centre on full moon days and non-full moon days.     

Canine and feline emergency room visits and the lunar cycle: 11,940 cases (1992-2002)

OBJECTIVE: To determine the frequency of canine and feline emergency visits with respect to the lunar cycle. DESIGN: Retrospective case series. ANIMALS: 11,940 dogs and cats evaluated on an emergency basis during an 11-year period. PROCEDURES: Date of emergency visit, signalment, and chief complaint were retrieved from a medical records database. Emergency type was categorized as animal bite, cardiac arrest, epilepsy, ophthalmic, gastric dilatation-volvulus, trauma, multiple diseases, neoplasia, or toxicosis. The corresponding lunar phase was calculated and recorded as new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, or waning crescent. The effect of lunar phase on the frequency of emergency visits was evaluated by calculating relative risk. RESULTS: Of 11,940 cases, 9,407 were canine and 2,533 were feline. Relative risk calculations identified a significant increase in emergencies for dogs and cats on fuller moon days (waxing gibbous to waning gibbous), compared with all other days. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that more emergency room visits occurred on fuller moon days for dogs and cats. It is unlikely that an attending clinician would notice the fractional increase in visits (0.59 and 0.13 more canine and feline visits, respectively) observed in this study at a facility with a low caseload. If the study is repeated at a facility with a robust emergency caseload, these results may lead to reorganization of staffing on fuller moon dates. A prospective study evaluating these findings under conditions of high caseload is necessary to determine the clinical relevance.     

Fertility of sows mated on different days of the week

The farrowing rates resulting from matings on different days of the week were determined for a 2800-sow intensive piggery in both 1983 and 1984. The results showed that sows mated early in the week achieved a significantly higher farrowing rate than sows mated late in the week (P less than 0.0001). During the seasonal (summer to autumn) infertility period, Wednesday matings resulted in a poor farrowing rate whereas for the rest of the year farrowing rates following Wednesday matings were similar to those for Sunday Monday and Tuesday matings. Consistent results were obtained for data from both years. It is proposed that the stress of regrouping unmated sows on Wednesday to accommodate newly weaned sows is responsible for this decrease in fertility. This study illustrates how detailed analysis of farrowing rates on a day of mating basis can identify a problem which is otherwise masked by weekly data.     

Relationship of the iridocorneal angle, as measured using ultrasound biomicroscopy, with post-operative increases in intraocular pressure post-phacoemulsification in dogs

Objective  To investigate the relationship of the iridocorneal angle as it appears on ultrasound biomicroscopy (UBM) to increases in IOP post-phacoemulsification in the canine eye.
Animals studied  47 eyes of 28 dogs of various age, sex, and breed.
Methods  The ciliary process and limbus were used as a reference points to measure the angle opening distance (AOD), which was set by multiplying 0.45 by the distance between the ciliary process and limbus (when measured from the ciliary process). Pressure measurements were taken at five set points: Before, immediately post-, one day post-, 1 week post-, and 1 month post-phacoemulsification.
Results  A weak relationship between the AOD and the IOP one day post-phacoemulsification (Intercept: 2.83, Slope: –1.24, P -value: 0.0155) was observed. No relationship immediately post-operative (Intercept: 3.45, Slope: –1.34, P -value: 0.0651), 1 week post-phacoemulsification (Intercept: 2.31, Slope: –0.01, P -value: 0.9829), 1 month post-phacoemulsification (Intercept: 1.85, Slope: –0.49, P -value: 0.1533) was observed. The pre-operative measurements made with UBM were: Distance from limbus to ciliary process (DLCP): (Minimum: 1.152, Maximum: 2.992, Mean: 1.91, SD: 0.468); AOD (Minimum: 0.104, Maximum: 0.764, Mean: 0.40, SD: 0.172).
Conclusions  The relationship between AOD as measured by UBM pre-operatively is weakly associated with IOP pressure elevations at day one post-phacoemulsification. Further study is required prospectively to establish the importance of this relationship. Initial measurements of the canine iridocorneal angle were created, suggesting a method to be used in the future to establish true canine normal measurements.     

Improved in vitro procedure for maintaining stock cultures of three genera of rumen protozoa

To maintain stock cultures of rumen protozoa, studies were initiated to explore possible methods for keeping the protozoa viable without feeding every day. Cultures of Entodinium caudatum, Epidinium caudatum, Enoploplastron triloricatum, and Entodinium exiguum were used to study the effect of not feeding for 1 or 2 d. The study lasted 88 d, and although bacterial concentrations decreased when cultures were not fed for 2 d (over the weekend), they recovered quickly with subsequent daily feedings. The exception was Enoploplastron triloricatum, which showed a gradual decline over the entire study. Addition of streptomycin to the media had little effect on maintaining bacterial concentrations in all cultures except Entodinium caudatum, in which the overall mean concentration was greater (P < 0.01). No differences in pH or bacterial concentrations were found between cultures fed daily and those held without feed for 2 d, with or without streptomycin. For maintaining protozoal cultures (10-mL volumes) over a long period without feeding on weekends, the following schedule is proposed: transfer and feed 0.12 mL of 1.5% ground wheat-1% orchardgrass on Monday; feed 0.12 mL of 1.5% ground wheat-1% orchardgrass on Tuesday, Wednesday, and Thursday; transfer and feed 0.5 mL of 1.5% ground wheat-1% orchardgrass on Friday; do not feed on Saturday and Sunday.     

Fournier's gangrene in a cat

Objective – To describe the clinical course of a cat diagnosed with Fournier's gangrene.
Case Summary – A 2-year-old castrated male cat was presented to an emergency hospital for evaluation of acute onset of lethargy, mucoid anal discharge, and fever. During hospitalization, with provision of supportive care, an area of necrotizing fasciitis around the prepuce and anus developed and surgical debridement was performed. Severe sepsis developed secondary to the necrotizing fasciitis and the cat was eventually euthanized.
New Information Provided – The purpose of this report is to document the first case of Fournier's gangrene in a cat that presented for mucoid anal discharge, lethargy, and mild ataxia, and to alert emergency clinicians to this disease process. Early detection of the disease with prompt, aggressive supportive care and surgical debridement is necessary for successful treatment.     

Colonic,ureteral, and vascular injuries secondary to stick impalement in a dog

Objective – To report the surgical repair, case management, and outcome of a dog with sepsis and severe intraabdominal trauma secondary to a penetrating stick injury. Case or Series Summary – A 1.5‐year‐old, spayed female, mixed‐breed dog was presented to the emergency service after incurring a small laceration on the medial aspect of the left pelvic limb while running in the woods. The wound was surgically explored and a primary closure achieved. The patient was discharged the same day with oral antimicrobial therapy. The following morning the dog was represented to the emergency service for acute vomiting. Abdominal radiographs were performed and demonstrated loss of serosal detail and pneumoperitoneum. An emergency celiotomy was performed and revealed distal colonic perforation, left ureteral laceration, and lacerations of the left common iliac vein. Ureteronephrectomy, as well as primary closure of the distal colonic perforation and left common iliac vein lacerations, were performed. The patient recovered and was ultimately discharged from the hospital 5 days later. Follow‐up 1 year later revealed no significant physical exam or biochemical abnormalities. New or Unique Information Provided – A seemingly benign penetrating stick injury initially deemed to be superficial in nature was later demonstrated to have resulted in sepsis following severe intraabdominal trauma that included lacerations of the distal colon, left ureter, and left common iliac vein in a dog. Successful surgical management and intensive care led to a full recovery without any residual impairment noted a year later.     

A Prospective, Randomized, Double-Blinded, Placebo-Controlled Study of Human Intravenous Immunoglobulin for the Acute Management of Presumptive Primary Immune-Mediated Thrombocytopenia in Dogs

Background: Immune-mediated thrombocytopenia (IMT) is a common hematologic disorder in dogs. Human intravenous immunoglobulin (hIVIG) may have a beneficial effect in canine IMT.
Hypothesis: A single hIVIG infusion (0.5 g/kg) in dogs with presumed primary IMT (pIMT) is a safe adjunctive emergency treatment to accelerate platelet count recovery and shorten hospitalization time without increasing the cost of patient care.
Animals: Eighteen client-owned dogs with a presumptive diagnosis of pIMT.
Methods: Prospective, randomized, double-blinded, placebo-controlled clinical trial.
Results: There were no identifiable immediate or delayed adverse reactions associated with hIVIG administration over a 6-month period. The median platelet count recovery time for the hIVIG group was 3.5 days (mean ± SD: 3.7 ± 1.3 days; range, 2–7 days) and 7.5 days (mean ± SD: 7.8 ± 3.9 days; range, 3–12 days) for the placebo group. The median duration of hospitalization for hIVIG group was 4 days (mean ± SD: 4.2 ± 0.4 days; range, 2–8 days) and 8 days (mean ± SD: 8.3 ± 0.6 days; range, 4–12 days) for the placebo group. There was no significant difference between groups with respect to expense of initial patient care, whereas significant reduction in platelet count recovery time ( P = .018) and duration of hospitalization ( P = .027) were detected in the hIVIG group.
Conclusions and Clinical Importance: Compared with corticosteroids alone, adjunctive emergency therapy of a single hIVIG infusion was safe and associated with a significant reduction in platelet count recovery time and duration of hospitalization without increasing the expense of medical care in a small group of dogs with presumed pIMT.     

The prevalence and significance of hyperglycemia in hospitalized cats

Objective – To report the prevalence of hyperglycemia in cats admitted to a veterinary hospital and to determine if hyperglycemic cats had increased morbidity and mortality when compared with normoglycemic cats.
Design – Retrospective clinical study.
Setting – Community-based referral hospital.
Animals – Nondiabetic cats admitted to the hospital.
Interventions – None.
Measurements and Main Results – The medical records of nondiabetic cats admitted to the hospital over a 1-year period were reviewed. There were 182 cats that met the criteria for inclusion in the study. Information obtained included signalment, length of hospitalization, initial and highest blood glucose measurement, diagnosis, treatment, and final disposition. Sixty-three percent of cats (116/182) were hyperglycemic at the time of presentation. Total incidence of hyperglycemia at any point during hospitalization was 64% (118/182). No association was found between hyperglycemia either initially or at any point during the hospitalization and mortality. However, a significant association was documented between the presence of hyperglycemia and increased length of hospitalization (LOH) ( P =0.04). The duration of LOH was also significantly associated with the degree of hyperglycemia ( P =0.01). A number of different disease processes were represented in the study population. However, the number of cats in each disease category was small and no association could be found between any of them and blood glucose affecting mortality and morbidity.
Conclusion – The prevalence of hyperglycemia in feline patients admitted to a primary referral hospital was 64%. Cats with hyperglycemia had a longer LOH when compared with normoglycemic cats; however, presence of hyperglycemia did not impact mortality in this population of cats.     

Use of human immunoglobulin in addition to glucocorticoids for the initial treatment of dogs with immune-mediated hemolytic anemia

Objective – To determine the utility of human intravenous immunoglobulin (hIVIG) for the initial treatment of canine immune-mediated hemolytic anemia (IMHA).
Design – Blinded, randomized, clinical trial.
Setting – Veterinary teaching hospital.
Animals – Twenty-eight, client-owned dogs with primary IMHA.
Interventions – At enrollment, after diagnosis of IMHA, dogs were randomly assigned to receive either hIVIG or placebo, in a blinded fashion. For the next 14 days, all dogs received glucocorticoids as the sole immunosuppressant agent. All dogs received low-molecular-weight heparin as an anticoagulant. D-dimer concentrations were evaluated at the beginning and end of the study protocol to monitor for thromboembolic complications.
Measurements and Main Results – Twenty-five of 28 dogs (89%) were discharged from the hospital. Thirteen of those received hIVIG and 12 received placebo. Twenty-four dogs (86%) were alive 14 days after enrollment, and of these 13 received hIVIG and 11 received placebo. D-dimer concentrations were elevated in 86% of all dogs at the time of diagnosis.
Conclusions – For initial treatment of dogs with IMHA, the addition of hIVIG to corticosteroid treatment did not improve initial response, nor did it shorten hospitalization.     

Serum Acute Phase Protein Concentrations in Dogs with Autoimmune Hemolytic Anemia

Background: Serial monitoring of acute phase protein (APP) concentrations in canine autoimmune hemolytic anemia (AIHA) has not been reported.
Hypotheses: Acute canine AIHA is accompanied by an acute phase response (APR) characterized by increased C-reactive protein (CRP) and α1-acid glycoprotein (AAG) concentrations and decreased albumin concentrations.
Animals: Twenty-seven dogs with AIHA and 11 control dogs.
Methods: Prospective, cohort study. CRP, AAG, and albumin concentrations, white blood cell (WBC) count, and packed cell volume (PCV) were determined at admission (day 1), every 48 hours until death or discharge, and on days 30, 90, 180, and 365.
Results: Compared with controls, CRP and AAG concentrations were increased and albumin concentration was decreased in dogs with AIHA (days 1–7; P < .002) and normalized with disease stabilization (days 9–365; P > .05). APP concentrations on day 1 were not predictive of survival, duration of hospitalization, or number of blood transfusions ( P = .153–.940). PCV correlated with APP concentrations over time (CRP r =−.600, AAG r =−.665, albumin r = .533; P < .0001) as did WBC count (CRP r = .253, AAG r = .486, albumin r =−.246; P < .006). Day 1 CRP concentration was lower for dogs that received corticosteroids before referral (115.3 μg/mL) compared with dogs that did not (191.2 μg/mL; P = .02).
Conclusions: An APR occurs in canine AIHA. Initial APP concentrations are not predictive of acute survival, correlate with hematologic markers of remission, and normalize rapidly with disease stabilization.     

Use of thromboelastography in dogs with immune-mediated hemolytic anemia: 39 cases (2000–2008)

Objective – To analyze thromboelastograms (TEGs) of naturally occurring cases of immune-mediated hemolytic anemia (IMHA) in order to identify whether a hypercoagulable state was present and whether its presence was associated with differences in survival.
Design – Retrospective study spanning January 2000 to June 2008. Medical records of dogs were evaluated. Endpoints were considered death or discharge from the hospital.
Setting – Academic teaching hospital.
Animals – Thirty-nine dogs with a diagnosis of IMHA and at least one TEG performed during hospitalization were included.
Interventions – None.
Measurements and Main Results – Four values were evaluated from the TEG: the R time (R), K time (K), alpha angle (α), and maximum amplitude. From these values, a coagulation index (CI) was calculated to classify patients as normocoagulable, hypercoagulable, or hypocoagulable. Thirty-three of 39 patients were hypercoagulable based on the CI. The 6 remaining dogs were normocoagulable. The patients with a normocoagulable CI had an increased mortality rate (100%) when compared with the hypercoagulable patients using Fisher's exact test ( P =0.02). Additionally, prolongation of partial thromboplastin time did not preclude hypercoagulable TEG values.
Conclusions – The majority of dogs with IMHA were hypercoagulable as measured by TEG. A normal CI was associated with a worse outcome in this patient population. TEG may provide additional and complementary information to prothrombin time and partial thromboplastin time relating to coagulation status in dogs with IMHA and may help predict prognosis and potentially guide clinical decisions to utilize anticoagulant drugs.     

Therapy and outcome of suspected alpha lipoic acid toxicity in two dogs

Objective – To report a suspected toxicity in 2 dogs; to discuss therapy and prognosis.
Series Summary – Suspected alpha lipoic acid (ALA) toxicity was diagnosed based on clinical history and compatible laboratory findings in 2 dogs. Case 1 was presented within 10 hours of ALA ingestion, with initial behavioral changes likely due to hypoglycemia. During the course of hospitalization, hypoglycemia persisted and evidence of acute hepatic insult developed. With aggressive supportive care (including IV fluids with dextrose supplementation, hepatoprotective medications, and a plasma transfusion), he made a full recovery. Case 2 was presented approximately 60 hours after ALA ingestion, and was found to be in oliguric renal failure. She was treated with IV fluids, gastroprotective medications, and furosemide, but her condition deteriorated and she was ultimately euthanized within 16 hours of admission to the hospital.
New or Unique Information Provided – ALA is an uncommon but serious toxin that should be considered in cases presenting with hypoglycemia, acute renal failure, or acute hepatic insult.     

Prevalence of malignancy when solitary versus multiple lesions are detected during abdominal ultrasonographic examination of dogs with spontaneous hemoperitoneum: 31 cases (2003–2008)

Objective – To compare the histopathologic diagnosis in dogs with spontaneous hemoperitoneum when abdominal ultrasonographic examination detects a solitary versus multiple lesions.
Design – Retrospective cross-sectional study.
Setting – Private veterinary hospital.
Animals – Client-owned dogs presented with spontaneous hemoperitoneum between March 1, 2003 and June 1, 2008.
Interventions – Dogs were divided into 2 groups based on presence of a solitary or multiple abdominal ultrasonographic lesions. Prevalences were compared between groups for malignancy and specifically hemangiosarcoma.
Measurements and Main Results – Ten of 31 (32%) dogs had a solitary abdominal ultrasonographic lesion and 21 of 31 (68%) had more than 1 lesion. The bleeding tissue was characterized as malignant in 8 of 10 (80%) dogs with solitary lesions and 17 of 21 (81%) dogs with multiple lesions; there was no significant difference ( P =1.0) between groups. In this study no association ( P =0.26) was found between the number of abdominal ultrasonographic lesions observed and subsequent diagnosis of hemangiosarcoma.
Conclusions – Solitary abdominal ultrasonographic lesions in dogs with spontaneous hemoperitoneum do not necessarily indicate a lower prevalence of malignancy.     

Coagulation effects of low molecular weight heparin compared with heparin in dogs considered to be at risk for clinically significant venous thrombosis

Objective – Compare the effects of 3 anticoagulation protocols on anti-factor Xa activity (AXa).
Design – Prospective, randomized, double-blind study.
Setting – University veterinary teaching hospital.
Animals – Eighteen dogs considered to be at risk for venous thrombosis.
Interventions – Each dog was randomly assigned to 1 of the following 3 groups ( n =6/group) and was treated for 24 hours: low-dose heparin (LDH), high-dose heparin (HDH), and dalteparin (DP). Dogs in the LDH group received a constant rate infusion (CRI) of unfractionated heparin (UFH) at 300 U/kg/d, the HDH group received a bolus of 100 U/kg of UFH IV, then a CRI of 900 U/kg/day, and the DP group received 100 U/kg DP SC at 0, 12, and 24 hours.
Measurements and Main Results – A total of 54 samples for activated partial thromboplastin time (aPTT) and AXa assays were collected at 0, 4, and 28 hours. Six samples had an AXa >0.1 U/mL, 5 of those were from the HDH group at hour 4. Two samples from the HDH group at hour 4 had a prolonged aPTT (93 and 200 seconds) and the highest AXa (0.6 and 1.0 U/mL, respectively). Four additional dogs in the HDH group did not complete the study due to hemorrhage; none of the dogs completing the study showed signs of hemorrhage.
Conclusions: Neither DP nor LDH increased AXa to values considered therapeutic in humans (0.5–1 and 0.35–0.75 U/mL, respectively), and both protocols appear to be inadequate to increase AXa in dogs with clinical illness. HDH increased AXa to this range in 2 of 6 dogs, but had unpredictable effects on aPTT and resulted in hemorrhage in some dogs.     

Splenectomy as an adjunctive treatment for dogs with immune-mediated hemolytic anemia: ten cases (2003–2006)

Objective – To describe the patient population, disease severity, and outcome in dogs with immune-mediated hemolytic anemia (IMHA) that underwent splenectomy. To compare presurgical and postsurgical data.
Design – Retrospective case series.
Setting – Emergency clinic/referral hospital.
Animals – Ten dogs diagnosed with IMHA.
Interventions – Splenectomy in addition to standard medical management for IMHA.
Measurements – Medical records of 10 dogs with IMHA, in which a splenectomy was performed were reviewed. The population was analyzed with regards to physical and clinicopathologic data, severity, treatment, and outcome. Outcome was defined as survival at 30 days, percentage of dogs on medications at 30 days, and number of relapses documented by 30 days. The presurgical and postsurgical PCV and transfusion requirements were documented and compared for each dog.
Results – Nine of 10 dogs survived to 30 days. Four of the 9 that survived were not on any immunosuppressive medications. There were no relapses during the 30 days. The 3-day postsplenectomy PCVs were significantly higher than presplenectomy. The number of transfusions administered postsplenectomy was significantly less than those administered presplenectomy.
Conclusion – The use of splenectomy may be associated with an improved outcome in dogs with IMHA.     

Reproducibility of Airway Responsiveness in Horses Using Flowmetric Plethysmography and Histamine Bronchoprovocation

Background: Inflammatory airway disease has a high prevalence in horses, but is often a diagnostic challenge. Flowmetric plethysmography and histamine bronchoprovocation (FP/HBP) is a simple and effective tool for diagnosis, but reproducibility of these measurements made over time has not been established.
Hypothesis: We hypothesize that the measurement of airway responsiveness in horses using FP/HBP is consistent over both short and long periods of time.
Animals: Twenty-nine healthy adult horses from 2 university herds.
Methods: In this prospective experimental study, airway responsiveness was determined in each horse at day 0 (baseline [BL]) with FP/ HBP, using PC35 (provocative concentration of histamine needed to increase Δ_flow by 35%) as a measure of airway responsiveness. Each horse was re-tested 1–4 weeks after BL (short-term [ST]) and again at 3–12 months after BL (long-term [LT]).
Results: In the ST period, 23/27 (85%) of the horses had a PC35 that was within 1 doubling concentration of histamine of their BL value, with a mean change of 0.52 doubling concentrations (95% CI 0.26–0.79, range 0–2.06). For the LT data, 19/26 (73%) of horses were within 1 doubling concentration of their BL value, with a mean change of 0.81 doubling concentrations (95% CI 0.45–1.17, range 0.14–3.10). There was no significant difference in reproducibility between the 2 groups of subjects.
Conclusions and Clinical Importance: Repeated measurements of airway responsiveness obtained with FP/HBP show acceptable reproducibility over time periods up to a year. However, caution must be used when testing horses when ambient air temperature is low.     

Multiple Rib Fracture Repair in a Neonatal Holstein Calf

Objectives— To report rib fracture repair in a neonatal calf using the Securos^® Cranial Cruciate Ligament Repair System (SCCLRS).
Study Design— Case report.
Animals— A 2-day-old female Holstein calf with fracture of right ribs 4–10.
Methods— On the day of admission the calf was anesthetized and rib fractures were repaired using open reduction and the SCCLRS.
Results— Rib fractures were successfully stabilized and the calf discharged from the hospital 8 days postoperatively.
Conclusions— Modification of previously reported use of the SCCLRS to repair rib fractures in foals was required because of the different anatomy in the calf. This new technique was rapidly and easily performed for a large number of fractured ribs in this case.
Clinical Relevance— Effective rib fracture repair in calves can be readily performed using the SCCLRS with modification of the technique reported in foals.     

Determination of cardiac output in neonatal foals by ultrasound velocity dilution and its comparison to the lithium dilution method

Objective – To compare cardiac output (CO) measured by use of lithium dilution (LiDCO) and ultrasound velocity dilution (UDCO) in conditions of high, intermediate, and low CO in anesthetized foals.
Design – Original prospective study.
Setting – University teaching hospital.
Animals – Six foals 1–3 days of age (38–45 kg).
Interventions – Neonatal foals were anesthetized and instrumented to measure direct blood pressure, heart rate, arterial blood gases, and CO. The CO was measured by use of LiDCO and UDCO techniques. Measurements were obtained from each foal at baseline and during low, intermediate, and high CO states. Measurements were converted to cardiac index (cardiac index=CO/body weight) values for statistical analysis. Agreement between the 2 methods was determined using Bland and Altman analysis and concordance correlation coefficients.
Measurements and Main Results – LiDCO determinations of CO ranged between 4.0 and 14.0 L/min resulting in cardiac index ranging between 75.5 and 310 mL/kg/min. There was no significant effect of blood pressure variation on bias or relative bias ( P =0.62 and 0.93, respectively). The mean bias and relative bias of UDCO (±SD) compared with LiDCO were −20.1±39.2 mL/kg/min and −7.7±23.4%, respectively. Concordance correlation coefficient between LiDCO and UDCO was 0.833.
Conclusions – When compared with LiDCO, the UDCO technique has acceptable clinical utility for measuring CO in healthy anesthetized newborn foals.     

Temporal Variability of Ventricular Arrhythmias in Boxer Dogs with Arrhythmogenic Right Ventricular Cardiomyopathy

Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is prevalent in the Boxer. There is little information on the temporal variability of ventricular arrhythmias within affected dogs.
Objective: To evaluate ambulatory electrocardiograms (AECG) from Boxers with ARVC for hourly variation in premature ventricular complexes (PVC) and heart rate (HR).
Animals: One hundred and sixty-two Boxer dogs with ARVC.
Methods: Retrospective, observational study of 1,181 AECGs collected from Boxer dogs at The Ohio State University from 1997 to 2004 was evaluated. The proportion of depolarizations that were PVCs was compared across each hour of the day, during six 4-hour periods of day, to the time after AECG application, and to the maximum and minimum HR.
Results: A lower proportion of PVCs was noted during early morning (midnight to 0400 hours) as compared with the morning (0800–1200 hours) and late (1600–2000 hours) afternoon ( P = .012). There was no increase in PVC proportion in the 1st hour after AECG application as compared with all other hours of the day ( P = .06). There was poor correlation between maximum (ρ= 0.19) and minimum (ρ= 0.12) HR and PVC proportion.
Conclusions and Clinical Importance: The likelihood of PVC occurrence in Boxer dogs with ARVC was relatively constant throughout the day, although slightly greater during the hours of 0800–1200 and 1600–2000. A biologically important correlation with HR was not apparent. The role of autonomic activity in the modulation of electrical instability in the Boxer with ARVC requires further study.