Retrospective study on the use of lidocaine constant rate infusions for the treatment of ileus in ruminants and camelids.

Limited knowledge exists regarding the use of lidocaine as a prokinetic in ruminants and camelids to treat gastrointestinal ileus. In this retrospective study, ruminant and camelid cases diagnosed with ileus and treated with a lidocaine constant rate of infusion were assessed for adverse reactions and medical outcomes. A review of medical records was performed to identify cases in which lidocaine was administered as a prokinetic. Ten cases were identified consisting of 8 cattle, 1 goat, and 1 alpaca. Nine animals improved with a lidocaine treatment. No adverse effects were reported during lidocaine administration. Nine animals were discharged, and 1 was euthanized.

Intravenous infusion of glucose improved farrowing performance of hyperprolific crossbred sows.

The sow at parturition is challenged with respect to energy status due to increases in energetic expenses associated with 1) nest building 2) uterine contractions, and 3) colostrum production. A previous study indicated that sows were depleted of glucogenic energy around farrowing. The aim was to investigate whether intravenous infusion of glucose from observed nest-building behavior to 24 h postpartum affected the farrowing kinetics and colostrum production in sows. Ten multiparous sows (DanBred landrace × DanBred Yorkshire) were fitted with a jugular vein catheter on each side (one for infusion and the other one for blood sampling). Sows were infused with either 0.9% saline (CON; n = 5) or 10% glucose (GLU; n = 5) solution at a constant rate of 125 mL/h. From day 108 of gestation, sows were fed once daily with 3.33 kg of a standard lactation diet. During farrowing, sows were monitored to register the onset of farrowing, time of birth, birth status (live or dead), sex, stillbirth rate (SR), and weight of newborn piglets. Farrowing assistance (FA) was provided when the birth interval exceeded 60 min. In late gestation, 1 mL of blood was collected every third hour for blood gas analysis and every sixth hour for harvesting plasma. During farrowing, 1 mL (for blood gas) and 9 mL of blood were collected at 0, 3, 6, 9, 12, 15, 18, 21, and 24 h in milk (HIM). Colostrum and milk samples were collected at 0, 6, 12, 18, 24, and 36 HIM and also at 3, 10, 17, and 24 d in milk. Compared with CON sows, GLU infusion decreased the SR (16.1% vs. 7.4%; P = 0.03), FA (21% vs. 9.0%; P = 0.01), and surprisingly also blood glucose at the onset of farrowing (5.53 vs. 5.09 mmol/L; P = 0.03), respectively. A tendency to higher plasma lactate at the onset of farrowing (P = 0.05) but decreased piglet mortality from 0 to 24 h (P = 0.06) was also found for GLU sows. No effects of treatment on farrowing duration or mean birth intervals were found. Lactate in whole blood (P = 0.003) and plasma (P = 0.002) was increased for GLU sows as compared with CON sows during the colostrum period. No effect of GLU infusion was seen on colostrum and milk composition and yield. The increase in lactate was most likely due to a shift toward a greater proportion of glucose oxidation and insufficient O2 supply to fuel uterine contractions. In conclusion, infusion of glucose reduced the frequency of SR and FA, and improved energy status of the sow which seems to be crucial to enhance total piglet survival.

Assessment of the physical compatibility of injectable enrofloxacin with commonly used intravenous fluids and drugs during simulated Y-port administration.

OBJECTIVE: To evaluate physical compatibility of small animal (SAE) and large animal (LAE) injectable formulations of enrofloxacin with select IV fluids and drugs. SAMPLE: 162 admixtures containing SAE or LAE with saline (0.9% NaCl) solution, lactated Ringer solution (LRS), Plasma-Lyte A (PLA), 6% hydroxyethylstarch 130/0.4 (HES), metoclopramide, or ampicillin-sulbactam. PROCEDURES: In the first of 2 simultaneously conducted experiments, admixtures containing enrofloxacin (10 mg/kg) and a volume of IV fluid that would be administered over a 20-minute period when dosed at the maintenance infusion rate (40 mL/kg/d for saline solution, LRS, and PLA and 20 mL/kg/d for HES) were created. In the second experiment, enrofloxacin (10 mg/kg) was admixed with saline solution (40 mL/kg/d) and metoclopramide (2 mg/kg/d) or ampicillin-sulbactam (30 mg/kg). In both experiments, admixture components were infused into a flask over 20 minutes assuming patient weights of 5, 10, and 20 kg. Admixtures were created by use of undiluted SAE and SAE diluted 1:1 with saline solution and undiluted LAE and LAE diluted 1:1 and 1:10 with saline solution. Admixtures were assessed for physical incompatibility at 0, 15, 30, and 60 minutes after completion of mixing. Physical incompatibility was defined as gross precipitation, cloudiness, Tyndall effect, or change in turbidity. RESULTS: Admixtures containing undiluted SAE or LAE were physically incompatible with saline solution, PLA, LRS, and HES. Because saline solution was used to dilute SAE and LAE, all admixtures containing diluted SAE or LAE were also physically incompatible. Physical compatibility of enrofloxacin with metoclopramide or ampicillin-sulbactam could not be assessed because those admixtures also contained saline solution. CONCLUSIONS AND CLINICAL RELEVANCE: Enrofloxacin was physically incompatible with all tested solutions.

Lispro insulin and electrolyte supplementation for treatment of diabetic ketoacidosis in cats.

BACKGROUND: Intravenous continuous rate infusion (IVCRI) of lispro at a starting dose of 0.09 U/kg/h and the use of 0.9% sodium chloride (NaCl) for fluid resuscitation in cats with diabetic ketoacidosis (DKA) have not been reported. Protocols for correction of electrolyte deficiencies in cats with DKA are lacking. OBJECTIVES: To characterize the use of IVCRI lispro at an initial dose of 0.09 U/kg/h and the use of NaCl for resuscitation. Explore protocols for electrolyte supplementation in cats with DKA. ANIMALS: Twelve cats with DKA enrolled from the cat population of a university hospital. METHODS: Randomized, controlled, blinded study. Six cats were randomized into each group, the lispro insulin treatment group (LITG) and regular insulin treatment group (RITG). All cats received IVCRI fluid resuscitation with NaCl. Solutions with higher than previously published electrolyte concentrations were used to treat electrolyte deficiencies. RESULTS: The median time to blood glucose (BG) concentration <250 mg/dL was significantly shorter in the LITG (median 7 hours, 2-10 hours) than the RITG (median 12.5 hours, 8-20 hours; P = .02). Two cats had nonclinical hypoglycemia (BG = 40 mg/dL). The most rapid change in 157 measurements of corrected sodium concentrations was 0.7 mmol/L/h. Low concentrations of serum sodium, potassium, phosphate, and magnesium were over 3 times more common than above normal electrolyte concentrations, despite supplementation with fluids of high electrolyte concentrations. CONCLUSIONS AND CLINICAL IMPORTANCE: Lispro at a starting dose of 0.09 U/kg/h and NaCl administered for fluid resuscitation are safe and effective for treatment of DKA in cats.

Evaluation of an outpatient protocol in the treatment of canine parvoviral enteritis.

OBJECTIVE: To compare 2 treatment protocols (standard in-hospital versus modified outpatient) in affecting the duration of treatment or survival of dogs with parvoviral enteritis. DESIGN: Prospective, randomized study. SETTING: University teaching hospital. ANIMALS: Client-owned dogs with naturally acquired parvovirus were randomized to receive either an inpatient (n = 20) or outpatient (n = 20) treatment protocol. INTERVENTIONS: Both groups received intravenous (IV) fluid resuscitation and correction of hypoglycemia at hospital admission. Following stabilization, basic inpatient interventions included administration of IV fluids, administration of cefoxitin (22 mg/kg IV q 8 h), and maropitant (1 mg/kg IV q 24 h). Basic outpatient interventions (provided in-hospital) included administration of subcutaneous (SC) fluid (30 mL/kg q 6 h), administration of maropitant (1 mg/kg SC q 24 h) and cefovecin (8 mg/kg SC once). Using daily electrolyte and glucose evaluations, dextrose and potassium supplementation was provided intravenously (inpatients) or orally (outpatients) as indicated. Rescue criteria were used in both groups for analgesia and nausea. All dogs were syringe fed a commercial canine convalescence diet (1 mL/kg PO q 6 h) until voluntary appetite returned. MEASUREMENTS AND MAIN RESULTS: Protocol success, defined as survival to hospital discharge, was 90% (18/20) for the inpatient group compared to 80% (16/20) for the outpatient group (P = 0.66). There was no difference detected in duration of hospitalization for inpatient dogs (4.6 ± 2 days) versus outpatient dogs (3.8 ± 1.8 days, P = 0.20). Metabolic disturbances were frequent in the outpatient group, with 50% of dogs requiring dextrose supplementation and 60% of dogs requiring potassium supplementation. CONCLUSIONS: An outpatient protocol may be a reasonable alternative for dogs that cannot receive standard in-hospital treatment for parvoviral enteritis. Diligent supportive care and monitoring are still required to optimize treatment of dogs with parvoviral enteritis in an outpatient setting.

Intravenous immunoglobulin transfusion in colostrum-deprived dairy calves.

Immunoglobulin transfusion is employed in the management of the failure of passive transfer (FPT). The aim of this study was to investigate the dose of immunoglobulin G (IgG) needed to reach a protective concentration (>10 g/L) in colostrum-deprived dairy calves. Twenty-eight Holstein Friesian newborn male calves were randomly assigned to either a control group (CG) or a treatment group (PG). Calves in the CG received 4 L of high quality colostrum within 12 h of birth. Calves in the PG received 62.7 ± 3.1 g of IgG IV in 2.6 ± 0.3 L of plasma within 6 h after birth. Serum immunoglobulin G (sIgG) and serum total protein (sTP) concentrations were assayed before and after (24 h, 72 h and 1 week after birth) plasma transfusion or colostrum ingestion. Serum (s) IgG and sTP concentrations increased in both groups throughout the period of observation. Mean sIgG and sTP concentrations after colostrum ingestion or plasma transfusion were higher in the CG than in the PG (P <0.01). Nine treated calves developed diarrhoea during the study and four were humanely euthanased due to progressive clinical deterioration. None of the calves in the CG showed signs of disease or died during the study. The dose of IgG used in this trial effectively provided an adequate sIgG concentration in colostrum-deprived calves (>10 g/L). Calves in the CG had significantly lower morbidity and mortality rates compared to those in the PG, suggesting that plasma transfusion alone is ineffective in providing complete protection against neonatal disease.

A randomized clinical trial evaluating metabolism of colostral and plasma derived immunoglobulin G in Jersey bull calves.

BACKGROUND: Intravenous plasma administration has been recommended in healthy or sick calves with failure of passive immunity. HYPOTHESIS: IV administered plasma-derived immunoglobulin G (IgG) undergoes increased catabolism as reflected by a rapid decrease in serum IgG concentration with an increase in fecal IgG concentrations within 48 h. ANIMALS: Thirty newborn Jersey calves. Fifteen were fed colostrum (CL group) and 15 were given bovine plasma IV (PL group). MATERIALS AND METHODS: Randomized clinical trial. Calves in the CL group were fed 3 L of colostrum once, by oroesophageal tubing. Calves in the PL group were given plasma IV at a dosage of 34 mL/kg. Serum and fecal samples were collected at 0 h, 6 h, 12 h, 48 h, 5 d, and 7 d. Serum and fecal IgG concentrations were determined by radial immunodiffusion. RESULTS: Calves in the CL group maintained serum IgG concentrations consistent with adequate transfer of immunity (≥1,000 mg/dL) throughout the study period. Calves in the PL group achieved median IgG concentrations of ≥1,000 mg/dL at 6 h but the concentrations were <1,000 mg/dL by 12 h. Calves in the PL group were 5 times more likely to experience mortality compared to the CL group (hazard ratio = 5.01). Fecal IgG concentrations were not different between the 2 groups during the first 48 h (P > .05). CONCLUSIONS AND CLINICAL IMPORTANCE: Catabolism of plasma derived IgG occurs rapidly during the first 12 h after transfusion. Fecal excretion did not explain the fate of the plasma derived IgG.

Accuracy of potassium supplementation of fluids administered intravenously.

BACKGROUND: Potassium (K+) supplementation of isotonic crystalloid fluids in daily fluid therapy is commonly performed, yet its accuracy in veterinary medicine is undetermined. OBJECTIVE: To investigate the accuracy of K+ supplementation in isotonic crystalloid fluids. ANIMALS: None. METHODS: Observational study. 210 bags of fluid supplemented with KCl being administered to hospitalized dogs and cats intravenously (IV) were sampled over a 3-month period. Measured K+ concentration ([K+]) was compared to the intended [K+] of the bag. In a second experiment, 60 stock fluid bags were supplemented to achieve a concentration of 20 mmol/L K+, mixed well and [K+] was measured. In another 12 bags of 0.9% NaCl, K+ was added without mixing the bag, and [K+ ] of the delivered fluid was measured at regular time points during constant rate infusion. RESULTS: The measured [K+] was significantly higher than intended [K+] (mean difference 9.0 mmol/L, range 6.5 to >280 mmol/L, P < .0001). In 28% of clinical samples measured [K+] was ≥5 mmol/L different than intended [K+]. With adequate mixing, K+ supplementation of fluids can be accurate with the mean difference between measured and intended [K+] of 0.7 (95% CI -0.32 to 1.7) mmol/L. When not mixed, K(+) supplementation of 20 mmol/L can lead to very high [K+] of delivered fluid (up to 1410 mmol/L). CONCLUSIONS AND CLINICAL IMPORTANCE: Inadequate mixing following K+ supplementation of fluid bags can lead to potentially life threatening IV infused [K+]. Standard protocols for K+ supplementation should be established to ensure adequate mixing.

Clinical efficacy and safety of a water-soluble micellar paclitaxel (Paccal Vet) in canine mastocytomas.

OBJECTIVE: To determine the clinical efficacy and safety of a cremophor-free formulation of paclitaxel (Paccal Vet, Oasmia Pharmaceuticals) in dogs with mast cell tumours. METHODS: Paccal Vet was administered at a median dose of 145 (range, 135 to 150) mg/m(2) intravenously once every 21 days for three cycles to 29 dogs with macroscopic grade 2 or 3 mast cell tumour. Efficacy was assessed by tumour response (Response Evaluation Criteria in Solid Tumours version 1.0) and performance status score. Progression-free survival, quality of life and safety/adverse events were also evaluated. Clinical safety was assessed by clinicopathological analyses and recording of adverse events. RESULTS: Complete or partial response was observed in 59% of dogs. Performance status score remained constant or improved for 20 dogs and decreased by one grade for 9 dogs. Median time to progression was 247 (range, 42 to 268) days. Expected, transient frequently subclinical adverse events (primarily grade 3/4 neutropenia and grade 1/2 leukopenia) were observed in the majority of dogs. Nine dogs were euthanased and one dog died due to disease progression. CLINICAL SIGNIFICANCE: Paccal Vet appears to be a clinically safe and effective treatment for canine mast cell tumours. Further controlled confirmatory investigation is warranted.

Effect of parenteral l-alanyl-l-glutamine administration on phagocytic responses of polymorphonuclear neutrophilic leukocytes in dogs undergoing high-dose methylprednisolone sodium succinate treatment.

OBJECTIVE: To determine whether parenteral l-alanyl-l-glutamine (Ala-Gln) administration modulated phagocytic responses of polymorphonuclear neutrophilic leukocytes (PMNs) from dogs undergoing high-dose methylprednisolone sodium succinate (MPSS) treatment. ANIMALS: 15 healthy Beagles. PROCEDURES: Dogs were randomly assigned to 3 treatment groups (n = 5/group): 38-hour IV infusion of saline (0.9% NaCl) solution (control group), saline solution with 8.5% amino acids (2.3 g/kg/d), or saline solution with 8.5% amino acids (1.8 g/kg/d) and 20% l-alanyl-l-glutamine (Ala-Gln; 0.5 g/kg/d). High-dose MPSS treatment was initiated at the same time that IV infusions began, such that a total dose of 85 mg of MPSS/kg was administered through multiple IV injections over a 26-hour period. The infusions were maintained until 12 hours after the last MPSS injection. Blood samples collected before MPSS injections began and 2, 12, and 24 hours after injections ceased were used to evaluate PMN function. RESULTS: MPSS injections resulted in an increase in the total number of circulating leukocytes and increases in neutrophil and monocyte counts but did not affect lymphocyte, eosinophil, or basophil counts. Lymphocyte counts in the Ala-Gln group were higher than in the control group 12 hours after MPSS injections finished. Relative to preinfusion values, phagocytic capacity, oxidative burst activity, and filamentous actin polymerization of PMNs were suppressed in all dogs except those that received Ala-Gln. CONCLUSIONS AND CLINICAL RELEVANCE: Parenteral Ala-Gln administration in dogs resulted in an increase in PMN phagocytic responses that were suppressed by high-dose MPSS treatment.

The effect of intravenous insulin infusion on renal blood flow in conscious sheep is partially mediated by nitric oxide but not by prostaglandins.

To test the effect of insulin on renal perfusion and the participation of NO and PG as mediators of this response, renal blood flow (RBF) was measured in sheep (n = 8) implanted with ultrasonic flow probes around renal arteries and with a systemic arterial pressure (SAP, n = 4) telemetry device. Three protocols were performed: 1) RBF and SAP were recorded (0800 to 1800 h) in fed and fasted sheep, with the latter receiving intravenous (i.v.) infusions (0.5 mL/min) of insulin at 2 or 6 mU/(kg·min); 2) fasted sheep received i.v. infusions of either an inhibitor of NO synthesis (N(G)-nitro-L-arginine methyl ester, L-NAME) alone [0.22 mg/(kg·min), 1000 to 1200 h] or L-NAME (1000 to 1200 h) + insulin during the second hour (6 mU/(kg·min), 1100 to 1200 h); and 3) the same protocol was followed as in protocol 2, substituting L-NAME with ketoprofen [0.2 mg/(kg·min)], a cyclooxygenase inhibitor. In all protocols, plasma insulin and glucose were determined. During insulin administration, euglycemia was maintained and hypokalemia was prevented by infusing glucose and KCl solutions. After the onset of meals, a long-lasting 18% increase in RBF and a 48% insulin increase were observed (P < 0.05), without changes in SAP. Low- and high-dose insulin infusions increased RBF by 19 and 40%, respectively (P < 0.05). As after meals, the increases in RBF lasted longer than the insulin increase (P < 0.05). The L-NAME infusion decreased RBF by 15% (P < 0.05); when insulin was added, RBF increased to preinfusion values. Ketoprofen decreased RBF by 9% (P < 0.05); when insulin was added, RBF increased to 13% above preinfusion values (P < 0.05). In no case was a modification in SAP or glucose noted during the RBF changes. In conclusion, insulin infusion mimics the meal-dependent increase in RBF, independent of SAP, and lasts longer than the blood insulin plateau. The RBF increase induced by insulin was only partially prevented by L-NAME. Ketoprofen failed to prevent the insulin-dependent RBF increase. Both facts suggested that complementary vasodilatatory agents accounted for the insulin effect on sheep renal hemodynamics.

Effects of acute dilutional hyponatremia on acid-base changes and electrolyte concentrations in rats with bilateral renal pedicle ligation.

OBJECTIVE: To describe the effects of increasing the extracellular fluid (ECF) volume by approximately 20% on acid-base changes and electrolyte concentrations in anesthetized rats. ANIMALS: 18 adult male Sprague-Dawley rats. PROCEDURES: Rats were assigned to a control group (n = 6 rats) and a treatment group (12). All rats were anesthetized, and instrumentation and bilateral renal pedicle ligation were performed. The treatment group was infused IV with sterile water throughout a 30-minute period. Acid-base variables and concentrations of electrolytes, lactate, albumin, phosphorus, and hemoglobin were measured before (baseline) and 30 and 60 minutes after onset of infusion. Anion gap, strong ion difference, strong ion gap, and contributions of sodium, chloride, albumin, phosphorus, and lactate concentrations to base excess were calculated at each time point. RESULTS: Infusion of sterile water led to an increase in ECF volume of approximately 18%. This had no effect on acid-base balance, compared with that in control rats. Infusion of sterile water caused a significant decrease in sodium, chloride, ionized calcium, lactate, and albumin concentrations, compared with concentrations in the control group. Anion gap and calculated effects of sodium, chloride, albumin, and lactate concentrations on base excess at 60 minutes differed significantly between infused and control rats. CONCLUSIONS AND CLINICAL RELEVANCE: Infusion of sterile water did not cause clinically relevant dilutional acidosis. The acidotic impact of water administration was offset by generation of new bicarbonate via carbonic acid equilibration and intracellular buffering in combination with the alkalotic effects of decreases in albumin, phosphorus, and lactate concentrations.

Effects of intravenous infusion of trans-10, cis-12 18:2 on mammary lipid metabolism in lactating dairy cows.

It has previously been established that supplementation of trans-10, cis-12 18:2 reduces milk fat content and fat deposition in several species. The objectives of the study were 1) to examine whether potential mechanisms by which trans-10, cis-12 18:2 is reported to affect lipid metabolism in adipose tissue of different species could be partly responsible for the inhibition in milk fat synthesis in lactating dairy cows; and 2) to investigate the effects of trans-10, cis-12 18:2 on the expression of a newly identified isoform of stearoyl-coenzyme A desaturase (SCD) in bovine mammary tissue. Four primiparous Holstein cows in established lactation, fitted with indwelling jugular catheters, were used in a balanced 2 x 2 crossover design. For the first 5 d of each period, cows were infused intravenously with a 15% lipid emulsion providing 10 g/d of either cis-9, cis-12 18:2 (control) or trans-10, cis-12 18:2 (conjugated linoleic acid; CLA). On d 5 of infusion, mammary gland biopsies were performed and tissues were analyzed for mRNA expression of acetyl-coenzyme A carboxylase, fatty acid synthetase, lipoprotein lipase, SCD1, SCD5, sterol regulatory element-binding protein-1, IL6, IL8, and tumor necrosis factor-alpha by real-time PCR. Compared with the control treatment, CLA reduced milk fat concentration and yield by 46 and 38%, respectively, and increased the trans-10, cis-12 18:2 content in milk fat from 0.05 to 3.54 mg/g. Milk yield, milk protein, and dry matter intake were unaffected by treatment. Infusion of the CLA treatment reduced the mRNA expression of acetyl-coenzyme A carboxylase and fatty acid synthetase by 46 and 57%, respectively, and tended to reduce the expression of SCD1 and lipoprotein lipase. Abundance of mRNA for sterol regulatory element-binding protein-1 was reduced by 59% in the CLA treatment group. However, infusing trans-10, cis-12 18:2 did not affect the expression of transcripts for SCD5, tumor necrosis factor-alpha, IL6, and IL8. Results from the current study corroborate the idea that effects of trans-10, cis-12 18:2 reported on adipose tissue in animal models and humans are not part of the response in the inhibition of milk fat synthesis in lactating dairy cows. They also support the hypothesis that SCD1 and SCD5 present important differences in their regulation and physiological roles.

Effect of intravenous calcium borogluconate and sodium phosphate in cows with parturient paresis.

Thirty cows with parturient paresis were divided into three groups of 10. All the cows were given 500 ml of a 40 per cent calcium borogluconate solution intravenously over a period of 10 minutes, and 20 were also given 500 ml of a 10 per cent solution of sodium phosphate intravenously; in 10 of the cows this solution was administered over a period of 10 minutes immediately after the calcium borogluconate solution, and in the other 10 cows 200 ml of the solution was administered rapidly and the remaining 300 ml was added to 10 litres of sodium chloride and glucose solution and infused slowly over six hours. There were no significant differences between the groups with respect to the outcome of the treatments; six or seven of the cows in each group stood within eight hours of the treatment. There were no significant differences between the changes in serum calcium concentrations among the groups. The mean concentrations of inorganic phosphorus in the groups given sodium phosphate were increased above the normal range initially, but after eight hours there were no significant differences between the groups in terms of the numbers of cows that were hypophosphataemic. There were no significant differences between the three groups with respect to changes after treatment in the serum concentrations of magnesium or parathyroid hormone.

Plasma levels of a low-dose constant-rate-infusion of ketamine and its effect on single and repeated nociceptive stimuli in conscious dogs.

This study quantitatively investigated the analgesic action of a low-dose constant-rate-infusion (CRI) of racemic ketamine (as a 0.5 mg kg(-1) bolus and at a dose rate of 10 microg kg(-1) min(-1)) in conscious dogs using a nociceptive withdrawal reflex (NWR) and with enantioselective measurement of plasma levels of ketamine and norketamine. Withdrawal reflexes evoked by transcutaneous single and repeated electrical stimulation (10 pulses, 5 Hz) of the digital plantar nerve were recorded from the biceps femoris muscle using surface electromyography. Ketamine did not affect NWR thresholds or the recruitment curves after a single nociceptive stimulation. Temporal summation (as evaluated by repeated stimuli) and the evoked behavioural response scores were however reduced compared to baseline demonstrating the antinociceptive activity of ketamine correlated with the peak plasma concentrations. Thereafter the plasma levels at pseudo-steady-state did not modulate temporal summation. Based on these experimental findings low-dose ketamine CRI cannot be recommended for use as a sole analgesic in the dog.

Effects of nutritionally induced metabolic acidosis with or without glutamine infusion on acid-base balance, plasma amino acids, and plasma nonesterified fatty acids in sheep.

This study characterized the effects of nutritionally induced metabolic acidosis with or without Gln infusion on acid-base balance, plasma AA, and plasma NEFA in sheep. In a randomized complete block design with a 2 x 2 factorial arrangement of treatments, 24 fully fleeced sheep (Rideau-Arcott, 63.6 +/- 5.9 kg of BW) were fed a control supplement (CS; 300 g/d of canola meal) or an acidosis supplement (AS; 300 g/d of NutriChlor; HCl-treated canola meal), offered twice daily at 0700 and 1100 h. Sheep were infused at 1400 h daily with 0.3 g of L-glutamine per kg of BW or saline via jugular vein catheters for 7 d. The sheep were individually housed and limit-fed a basal diet of dehydrated alfalfa pellets (1.75 kg/d; 90% DM, 22% CP, and 1.2 Mcal of NE(g)/kg on a DM basis) offered twice daily at 1000 and 1300 h. Blood and urine was sampled daily between 1100 and 1130 h, and blood samples were analyzed for hematocrit, plasma pH, gases, strong ions, AA, and NEFA, whereas urine was analyzed for pH. The AS reduced (P < 0.01) DMI, urine and plasma pH, blood urea, partial pressure of CO(2), strong ion difference, and plasma HCO(3)(-), and increased (P < 0.01) plasma K(+), Ca(2+), and Cl(-). The AS with saline infusion increased (P

Analgesia for the critically ill dog or cat: an update.

Acute pain reliably accompanies severe illness and injury, and when sufficiently severe, it can complicate the recovery of critically ill patients. Because acute pain is closely tied to the neurologic process of nociception, pharmacologic therapy is often essential and effective. This update focuses on two methods of treatment of acute pain-local anesthetic infusion and continuous intravenous infusion of multimodal agents-that can be layered on top of standard care with other drugs.

Suspected albuterol toxicosis in a dog.

CASE DESCRIPTION: A 6-year-old male castrated Shetland Sheepdog was evaluated because of severe hypokalemia and progressive paresis. CLINICAL FINDINGS: Physical examination revealed fever, tachypnea, mydriasis, hyperemic mucous membranes, severe forelimb paresis, and hind limb paraplegia. The dog had superficial and deep pain sensation in all 4 limbs. Forelimb spinal reflexes were considered normal, but hind limb reflexes were normal to slightly hyperreflexive. The panniculus reflex was considered to be normal, and cranial nerve reflexes were intact. A CBC revealed mild leukocytosis and erythrocytosis, and serum biochemical analysis revealed severe hypokalemia. Thoracic and abdominal imaging did not reveal relevant findings. Blood pressure and ECG findings were within reference limits. Questioning of the owner revealed possible exposure to albuterol via ingestion of medication intended for the owner's horse. Results of serum testing via immunoassay were suggestive of albuterol toxicosis. TREATMENT AND OUTCOME: Treatment included IV administration of an electrolyte solution and supplemental potassium chloride. The rate of potassium chloride supplementation was slowly decreased as serum potassium concentration increased. No other medical intervention was required, and the dog made a rapid and complete recovery. CLINICAL RELEVANCE: Ingestion of albuterol can lead to profound physical and serum biochemical abnormalities. Appropriate historical information should be obtained to identify possible sources and routes of exposure to intoxicants. Albuterol-induced hypokalemia can be successfully managed medically.

Ligneous conjunctivitis secondary to a congenital plasminogen deficiency in a dog.

CASE DESCRIPTION: A 7-month-old 16.6-kg (36.5-lb) sexually intact female Golden Retriever was evaluated because of progressive severe bilateral membranous conjunctivitis, oral lesions, nasal discharge, and cough. CLINICAL FINDINGS: Histologic examination of conjunctival biopsy specimens revealed findings consistent with ligneous conjunctivitis. Circulating plasminogen activity was repeatedly low, and congenital plasminogen deficiency was identified as the underlying cause of the ocular, oral, and respiratory lesions. TREATMENT AND OUTCOME: Topical and subconjunctival administrations of fresh frozen plasma (FFP), topical administration of cyclosporine, and oral administration of azathioprine had no effect on the conjunctival membranes. Excision of the membranes followed by intensive treatment with topical applications of heparin, tissue plasminogen activator, corticosteroid, and FFP and IV administration of FFP prevented membrane regrowth. Intravenous administration of FFP increased plasma plasminogen activity to within reference limits, improved respiratory and oral lesions, and resulted in weight gain; discontinuation of this treatment resulted in weight loss, signs of depression, and worsening of lesions. After euthanasia because of disease progression, necropsy findings included mild hydrocephalus; multifocal intestinal hemorrhages; and fibrinous plaques in the oral cavity, nasopharynx, trachea, esophagus, and pericardium. Microscopically, the plaques were composed of fibrin and poorly organized granulation tissue. Fibrin thrombi were present within vessels in the lungs, oral cavity, and trachea. CLINICAL RELEVANCE: In dogs, congenital plasminogen deficiency can occur and may be the underlying cause of ligneous conjunctivitis. A combination of surgical and medical treatments may improve conjunctival membranes, and administration of FFP IV appears to be effective in treating nonocular signs of plasminogen deficiency.

The effect of low dose rocuronium on globe position, muscle relaxation and ventilation in dogs: a clinical study.

OBJECTIVE: The purpose of this study was to evaluate globe position, muscle relaxation and changes in ventilatory parameters after intravenous administration of 0.1 mg/kg rocuronium. STUDY DESIGN: Prospective clinical study. ANIMAL STUDIED: Sixteen dogs of different breeds, with a body weight of 22.1 +/- 13 kg and age of 5.6 +/- 2.8 years (mean +/- SD), were anesthetized for a short ophthalmic examination requiring central position of the globe. PROCEDURES: All dogs were premedicated with 0.005 mg/kg medetomidine and 0.1 mg/kg methadone IV. Anesthesia was induced with propofol to effect and maintained with 10 mg/kg/h propofol by continuous rate infusion. Following endotracheal intubation all dogs breathed 100% oxygen via an anesthetic circle system. Neuromuscular function was assessed with an acceleromyograph (TOF-Guard, Organon Teknika NV, Turnhout, Belgium) and by stimulation of the nervus peroneus superficialis. The ventilation parameters were measured using spirometry and capnography. After baseline measurements 0.1 mg/kg rocuronium was administered IV. Minute volume (MV), tidal volume (Vt), respiratory rate (RR), end expiratory carbon dioxide concentration (PE'CO(2)) and maximal depression of the response of the first twitch (T1) of train-of-four (TOF) stimulation and train-of-four ratio (TOFR) was measured. The change in the position of the globe was recorded. RESULTS: T1 decreased to 61 +/- 18% and the TOF ratio to 45 +/- 21% of baseline values. Both parameters returned to baseline after 9 min. There was no significant reduction in MV, TV and RR and no increase in PE'CO(2). The globe rotated to a central position of 45 +/- 7.7 s after administration of rocuronium and remained there for 23 +/- 10.8 min in all dogs. CONCLUSION: Rocuronium administered intravenously at a dose of 0.1 mg/kg to dogs causes a central position of the globe but minimal impairment of ventilation parameters.