Evaluation of the analgesic effect of lidocaine and bupivacaine used to provide a brachial plexus block for forelimb surgery in 10 dogs

Twenty adult dogs weighing between 1.4 and 53.5 kg and aged between six months and nine years were anaesthetised and the brachial plexus was localised with the aid of a nerve stimulator. In 10 of the dogs a brachial plexus block was induced with a mixture of lidocaine and bupivacaine and the other 10 each received 0.25 ml/kg saline as a control. The end-tidal isoflurane concentration was maintained between 1.3 and 1.4 per cent during surgery for carpal arthrodesis or a fracture of the radius or ulna. Acute heart rate or blood pressure increases of 20 per cent or more were treated with 1 microg/kg fentanyl intravenously. Postoperatively, signs of pain were scored by a single blinded observer at hourly intervals until eight hours after the block had been induced, on a scale from 0 to 18. Dogs with pain scores above 5 received 0.1 to 0.2 mg/kg methadone intravenously, repeated as necessary. During surgery the control dogs received significantly more fentanyl (median 0.05 microg/kg/minute, range 0.02 to 0.20 microg/kg/minute) than the group given local anaesthetic (median 0 microg/kg/minute, range 0 to 0.02 microg/kg/minute). Postoperatively, the control group required significantly more methadone (median 0.2 mg/kg, range 0.1 to 1 mg/kg) than the treated group (median 0 mg/kg, range 0 to 0.13 mg/kg).     

Endoscopic evaluation of the gastroduodenal mucosa to determine the safety of short-term concurrent administration of meloxicam and dexamethasone in healthy dogs

OBJECTIVE: To evaluate the safety, with respect to the development of gastric ulcers and erosions, of concurrent administration of meloxicam and dexamethasone for 3 days to healthy dogs. ANIMALS: 20 conditioned purpose-bred research Beagles. PROCEDURE: Seven days prior to treatment, dogs were anesthetized for endoscopic evaluation of the upper portion of the gastrointestinal tract (ie, the gastric and duodenal mucosa). Five regions of the gastroduodenal area were scored by 2 investigators. Dogs were randomly assigned to 1 of 4 treatment groups as follows: saline-saline, dexamethasone-saline, saline-meloxicam, and dexamethasone-meloxicam groups. On days 1, 2, and 3, dogs received either dexamethasone or saline (0.9% NaCl) solution injections SC twice daily. On days 2, 3, and 4, dogs received either meloxicam or saline solution injections SC once daily. On day 2, dogs were anesthetized for a sham surgery (ie, electrostimulation). On day 5, the gastroduodenal area of each dog was reevaluated by use of endoscopic evaluation and histologic examination of biopsy specimens. RESULTS: The total endoscopic score of the dexamethasone-meloxicam group was significantly greater than the scores of the other groups. The dexamethasone-saline group had a mean cumulative score that was significantly greater than the saline-meloxicam or saline-saline groups. Endoscopic scores of the saline-meloxicam group were not significantly different from scores of the saline-saline group. No significant differences in histologic findings were found between groups. CONCLUSIONS AND CLINICAL RELEVANCE: In healthy dogs, meloxicam appears to be safe with regard to adverse effects on the gastrointestinal tract. Concurrent administration of dexamethasone and meloxicam is more likely to cause gastric erosions than meloxicam administration alone.     

Evaluation of a short glass fibre-reinforced tube as a model for cat femur for biomechanical testing of orthopaedic implants.

The biomechanical testing of tubes made of third generation short glass fibre-reinforced (SGFR) material approximating cat femurs was performed in order to determine their suitability as cat femur surrogates for the biomechanical testing of orthopaedic implants. The tubes were tested in compression, three-point bending, notch testing, and screw pullout. Thin walled (B1-tubes) had a 13% lower maximum load to failure, a 19% higher maximum strength and a 13% lower elastic modulus compared to cat femurs tested in compression. B1-tubes maximum load to failure in three-point bending and screw pullout strength were considerably lower compared to cat femurs (29% and 63%, respectively). Notch testing was not performed on B1-tubes due to low bending strength. Thicker walled (B2-tubes) had a 23% higher maximum load to failure, a 10% higher maximum strength and a 21% lower elastic modulus compared to cat femurs tested in compression. The comparison of B2-tubes and cat femurs in three-point bending revealed a 7% increase in maximum load to failure for the B2-tubes. Drilled B2-tubes (notch testing) were weaker with a 30% lower load to failure compared to cat femurs. A screw pullout comparison of B2-tubes and cat femurs revealed a 2% increase in maximum load to failure for the B2-tubes. These tubes were intended to provide a model as a suitable surrogate for cat femurs for testing the bending strength of various orthopaedic constructs involving plates and screws. Testing revealed that third generation SGFR tubes were not suitable for these purposes and emphasizes the need to carefully evaluate the suitability of any model.     

Histologic prognosticators in feline osteosarcoma: a comparison with phenotypically similar canine osteosarcoma

Objective— To investigate the histologic characteristics of feline osteosarcoma (OS) and compare the histologic data with phenotypically comparable canine OS. The effects of histologic and clinical variables on survival statistics were evaluated.
Study Design— Retrospective study.
Animals— Cats (n=62) and dogs (22).
Methods— Medical records of 62 cats with OS were reviewed for clinically relevant data. Clinical outcome was obtained by telephone interview. Histologic characteristics of OS were classified using a standardized grading system. Histologic characteristics in 22 feline skeletal OS were compared with 22 canine skeletal OS of identical location and subtype. Prognostic variables for clinical outcome were determined using multivariate analysis.
Results— Feline OS was characterized by moderate to abundant cellular pleomorphism, low mitotic index, small to moderate amounts of matrix, high cellularity, and a moderate amount of necrosis. There was no significant difference between histologic variables in feline and canine OS. Histologic grade, surgery, and mitotic index significantly influenced clinical outcome as determined by multivariate analysis. Tumor invasion into vessels was not identified as a significant prognosticator.
Conclusion— Feline and canine skeletal OS have similar histologic but different prognostic characteristics.
Clinical Relevance— Prognosis for cats with OS is related to histologic grade and mitotic index of the tumor.     

Nematology Research in Europe

 Nematology started in Europe at the end of the last century.In Belgium and the Netherlands for example the first nematological paper(in Dutch) appeared in 1876.It was prepared by de Man and dealt with soil nematodes.Nematology gradually increased in importance.This lead to the establish-ment of the European Society of Nematologists in 1953.Since then, ESN has arranged a symposium every two years with an increasing number of participants.During the last meeting in Dundee, this number exceeded 450.The Society distributes a membership directory and keeps contact with the members through 'Nematology News'.This newspaper reports on the events in the nematology labs and issued twice a year.     

Arterial-alveolar carbon dioxide tension difference and alveolar dead space in halothane anaesthetised horses

Arterial-alveolar carbon dioxide tension differences (a-A) PCO2 and alveolar dead space were measured during clinical halothane anaesthesia of 110 horses with the help of continuous infra-red carbon dioxide analysis of expiratory gas. Mean (a-A) PCO2 was 1.6 +/- 0.8 kPa. Alveolar dead space expressed as a percentage of alveolar tidal volume had a mean value of 23 +/- 13 per cent. Influence on (a-A) PCO2 and alveolar dead space of the following variables was tested statistically: age, weight, body position, respiration mode and duration of anaesthesia. (a-A) PCO2 was influenced positively by weight (P less than 0.0001) and adoption of dorsal recumbency (P less than 0.01). Alveolar dead space was influenced positively by weight (P less than 0.0005), adoption of dorsal recumbency (P less than 0.01), intermittent positive pressure ventilation (P less than 0.0001) and duration of anaesthesia (P less than 0.05).     

Two cases of intraoperative herniation of the endotracheal tube cuff

During anaesthesia for elective procedures, 2 dogs developed acute airway obstruction caused by herniation of the endotracheal cuff.This is an uncommon but potentially fatal complication especially when minimal monitoring of the patient leads to late recognition of the condition. The most typical symptoms are decreased thoracic excursions and tidal volume, absence of gas flow through the endotracheal tube, change in the capnographic waves morphology and increased airway pressures. In both cases desaturation of haemoglobin (measured by pulse oximetry) occurred in-between 6 and 8 minutes after cuff herniation. All signs normalised following partial deflation of the cuff. Careful management of cuff pressures especially when nitrous oxide is used, awareness of the condition and monitoring of the patient can prevent fatal consequences.     

The use of a catheter to provide brachial plexus block in dogs

The objective of the study was to devise a method to facilitate catheter placement to perform brachial plexus block in the dog. Lidocaine plus epinephrine was injected through a 3.5 French feeding tube secured in proximity of the brachial plexus. Cutaneous areas for the nerves of the distal forelimb were tested for nociceptive sensation by pinching the skin with hemostats. Five out of the 7 dogs developed a full motor and sensory block. The onset time for a full block and duration of blockade were 54 min, s = 17.1 and 39 min, s = 37.6, respectively. A second blockade was successfully achieved in 2 dogs in which the catheter was not displaced. An indwelling feeding tube is an effective way to provide blockade of the brachial plexus in the dog. The placement and the fixation of the catheter were critical for the production of a full block.     

Vertical Distribution of the Plant-Parasitic Nematode, Pratylenchus penetrans, Under Four Field Crops

ABSTRACT The vertical distribution of Pratylenchus penetrans was monitored in four fields cropped with maize, black salsify, carrot, or potato. Soil samples were collected at 21-day intervals from May 2002 until April 2003 from five plots (2 x 5 m(2)) per field. Per plot, 15 cores were taken to a depth of 70 cm and split into seven segments of 10 cm each. Within the plots, segments from corresponding depths were pooled. After mixing, 200-g subsamples were taken and nematodes were extracted by zonal centrifugation from the root fraction and the mineral soil fraction separately. In most crops, the root fraction contained more than 50% of the total number of P. penetrans. Because the ratio between the numbers of nematodes in the root fraction and mineral soil fraction changes during the growing season, numbers of P. penetrans found in the mineral soil fraction cannot be used to estimate the total number in the soil. Therefore, both fractions have to be processed to obtain a reliable estimate of the density. No nematodes were recovered below 50 cm soil depth, except in the maize field where nematodes were found at 70 cm. The optimum sampling depth for maize, black salsify, carrot, and potato was 45, 25, 25, and 35 cm, respectively. The percentage of nematodes per soil layer was independent of the sampling date, indicating that a defined optimum sampling depth will be applicable throughout all seasons. The cumulative vertical distribution, modeled with a logistic equation, can be used to estimate the sampling error when samples are collected at different depths.