Short duration anaesthesia for minor procedures in dogs

Anaesthesia was maintained with 4 different techniques in each of 12 dogs of ASA grades I or 11 undergoing 4 treatment sessions of mega-voltage x-ray therapy at weekly intervals. After induction of anaesthesia with propofol, these dogs received either: i) continiious pi-opofol iv infusion together with nitrous oxide/oxygen by inhalation: ii) halothane in nitrous oxiddoxygen; iii) entluraiie in nitrous oxide/oxygen; or iv) isollurane in nitrous oxide/oxygen. Anaesthesia dways enabled irradiation to be performed but stable anaesthesia was achieved more easily when enflurnne was used. The incidence of undesirable effects during anaesthesia wiis low. Recovery from the end of anaesthesia to swallowing was fastest Lifter enfluraiie (2.2 min median) but the recovery times to walking were similar (medians: halothane 12.5 min; entlurane 12.0 min; isoflurane 12.5 min; propofol I3 min). Personal preferences. local facilities and cost are likely to be the deciding factors in choice of any one of these techniques for dogs undergoing short procedures unussociatcd with surgical stimulation.     

Prevalence and distribution of meticillin-resistant Staphylococcus aureus within the environment and staff of a university veterinary clinic

O bjectives : To characterise the distribution of meticillin-resistant Staphylococcus aureus within the environment of a university small animal hospital and compare this with the distribution among staff.
M ethods : Samples were collected from 140 environmental sites and the anterior nares of 64 staff members at the University of Glasgow Small Animal Hospital on a single day (d1). Sixty of the environmental sites were resampled 14 days later (d14).
R esults : Meticillin-resistant S aureus was isolated from two of 140 (1·4 per cent; 95 per cent confidence interval: 1·7 to 5·1) environmental sites on d1 and one of 60 (1·7 per cent; 95 per cent confidence interval: 0·4 to 8·9) on d14. Two of the 64 staff sampled were positive for meticillin-resistant S aureus (3·1 per cent; 95 per cent confidence interval: 0·4 to 8·4).
C linical S ignificance : A lower prevalence of meticillin-resistant S aureus was observed in the environment than previously reported. The location, relatedness between isolates and the presence of Panton-Valentine leucocidin indicates that the source of the environmental meticillin-resistant S aureus was most likely to have been human rather than animal in these cases. This study presents important information regarding the potential source and distribution of meticillin-resistant S aureus within veterinary hospital environments and highlights potential variability of prevalence of meticillin-resistant S aureus within and between veterinary institutions.     

The effect of omeprazole on oesophageal pH in dogs during anaesthesia

O bjectives : Intra-operative, gastro-oesophageal reflux may be associated with post-anaesthestic complications such as oesophagitis and oesophageal stricture in dogs. The aim of this study was to investigate the effect of preoperative administration of omeprazole, a proton pump inhibitor, on oesophageal pH in anaesthetised dogs.
M ethods : Forty-seven dogs undergoing elective pelvic limb orthopaedic surgery were enrolled into the study. These were randomly allocated to treatment group (n=22) or control group (n=25). The treatment group received one dose of omeprazole (1 mg/kg po) at least 4 h before anaesthesia. All dogs were anaesthetised by the same standardised protocol. A pH probe was inserted into the distal oesophagus after induction of anaesthesia and oesophageal pH was continuously monitored.
R esults : In the treatment group, four animals (18 per cent) showed a sudden decrease in oesophageal pH (<4). In the control group the same phenomenon was detected in 13 animals (52 per cent). Gastro-oesophageal reflux occurred more frequently in the control group compared with the omeprazole group (odds ratio 4·7, 95 per cent C.I. 1.1 to 24.7, P=0.032).
C linical S ignificance : This study suggests that the preoperative administration of omeprazole is effective in reducing the incidence of gastro-oesophageal reflux during anaesthesia in dogs.     

A clinical trial of propofol infusion anaesthesia in dogs

Studies were carried out on 40 dogs premedicated with acepromazine (0·05 mg. kg^-1) and atropine (0·02 mg. kg^-1) to determine the minimum infusion rate of propofol needed to maintain anaesthesia and to compare the quality of the anaesthesia with that produced by halothane/nitrous oxide/oxygen. In 30 dogs anaesthesia was induced with propofol and maintained with a continuous infusion and in the other ten dogs anaesthesia was induced with thiopentone and maintained with the inhalation agents. An infusion rate of 0·4 mg. kg^-1 min^-1 of propofol produced surgical anaesthesia in dogs breathing oxygen or oxygen-enriched air. Cardiovascular and respiratory effects were similar to those in dogs anaesthetized with halothane/nitrous oxide and with both anaesthetic regimens myocardial oxygen consumption appeared to increase with increasing duration of anaesthesia. A possible familial susceptibility resulting in a more prolonged recovery was revealed and propofol infusion was associated with a 16 per cent incidence of vomiting in the recovery period. It was concluded that in canine anaesthesia the continuous infusion of propofol to maintain anaesthesia in healthy dogs was safe but less satisfactory than the use of halothane/nitrous oxide.     

Comparison of sevoflurane and isoflurane in dogs anaesthetised for clinical surgical or diagnostic procedures

OBJECTIVES: To assess attributes of sevoflurane for routine clinical anaesthesia in dogs by comparison with the established volatile anaesthetic isoflurane. METHODS: One hundred and eight dogs requiring anaesthesia for elective surgery or diagnostic procedures were studied. The majority was premedicated with 0.03 mg/kg of acepromazine and 0.01 mg/kg of buprenorphine or 0.3 mg/kg of methadone before induction of anaesthesia with 2 to 4 mg/kg of propofol and 0.5 mg/kg of diazepam. They were randomly assigned to receive either sevoflurane (group S, n=50) or isoflurane (group I, n=58) in oxygen and nitrous oxide for maintenance of anaesthesia. Heart rate, respiratory rate, indirect arterial blood pressure, haemoglobin saturation, vaporiser settings, end-tidal carbon dioxide and anaesthetic concentration and oesophageal temperature were measured. Recovery was timed. Data were analysed using analysis of variance and non-parametric tests. RESULTS: Heart rate (85 to 140/minute), respiratory rate (six to 27/minute) and systolic arterial blood pressure (80 to 150 mmHg) were similar in the two groups. End-tidal carbon dioxide between 30 and 60 minutes (group S 6.4 to 6.6 and group I 5.8 to 5.9 per cent) and vaporiser settings throughout (group S 2.1 to 2.9 and group I 1.5 to 1.5 per cent) were higher in group S. There was no difference in time to head lift (18+/-16 minutes), sternal recumbency (28+/-22 minutes) or standing (48+/-32 minutes). No adverse events occurred. CLINICAL SIGNIFICANCE: Sevoflurane appeared to be a suitable volatile anaesthetic for maintenance of routine clinical anaesthesia in dogs.     

Comparison of isoflurane and halothane as inhalation anaesthetics in the dog

A number of clinically important features of isoflurane anaesthesia were studied in comparison to those of halothane. Two groups of dogs were used. After light premedication, anaesthesia was induced by mask, and both groups of dogs were maintained for 30 minutes at 1.5 X MAC value of either halothane or isoflurane in a combination of oxygen and nitrous oxide (50:50). All animals were ventilating spontaneously. There was no difference in the speed of induction of the halothane and isoflurane groups. Blood pressure in both groups dropped to approximately 7.5 kPa (56 mm Hg) during maintenance anesthesia (1.5 MAC), while the heart rate was significantly higher in the isoflurane group. Individual respiratory variables were not significantly different between the two groups, however the differences between the trends of the mean values were significant (Sign-test). In general, with isoflurane, respiration rates were lower, with the tidal volume and end tidal CO2 being greater. The trends in pH and arterial pCO2 showed a slightly more severe respiratory acidosis in the isoflurane group. However, neither group showed values corresponding to any expected clinical problems. Speed of recovery (determined by times to head-lift and righting-reflex) was greater in the isoflurane group. Previously known important features of isoflurane are low biodegradability, low blood: gas partition coefficient, and decreased myocardial sensitivity to catecholamines. It is concluded from this study that isoflurane deserves a place in canine anesthesia whenever these specific pharmacologic properties are desired.     

Comparison of isoflurane and halothane as inhalation anaesthetics in the dog

Summary

A number of clinically important features of isoflurane anaesthesia were studied in comparison to those of halothane. Two groups of dogs were used. After light premedication, anaesthesia was induced by mask, and both groups of dogs were maintained for 30 minutes at 1.5 × MAC value of either halothane or isoflurane in a combination of oxygen and nitrous oxide (50:50). All animals were ventilating spontaneously.

There was no difference in the speed of induction of the halothane and isoflurane groups. Blood pressure in both groups dropped to approximately 7.5 kPa (56 mm Hg) during maintenance anesthesia (1.5 MAC), while the heart rate was significantly higher in the isoflurane group. Individual respiratory variables were not significantly different between the two groups, however the differences between the trends of the mean values were significant (Sign‐test). In general, with isoflurane, respiration rates were lower, with the tidal volume and end tidal CO₂ being greater.

The trends in pH and arterial pCO₂ showed a slightly more severe respiratory acidosis in the isoflurane group. However, neither group showed values corresponding to any expected clinical problems. Speed of recovery (determined by times to head‐lift and righting‐reflex) was greater in the isoflurane group. Previously known important features of isoflurane are low biodegradability, low blood: gas partition coefficient, and decreased myocardial sensitivity to catecholamines. It is concluded from this study that isoflurane deserves a place in canine anesthesia whenever these specific pharmacologic properties are desired.     

Ketone measurements using dipstick methodology in cats with diabetes mellitus

O bjectives : To compare the results of urine and plasma ketone dip test in a group of diabetic cats with possible ketosis or ketoacidosis, using laboratory plasma β-hydroxybutyrate measurements as the gold standard.
M ethods : According to clinical examinations, plasma β-hydroxybutyrate measurements and venous blood gas analysis, 54 cats with diabetes mellitus were classified as non-ketotic (n=3), ketotic (n=40) or ketoacidotic (n=11). Plasma and urine acetoacetate concentrations were determined using urine reagent strips.
R esults : Although there was a significant positive correlation between blood and urine ketone measurements (r=0·695, P<0·001), the results differed significantly (Z=−3·494, P<0·001). Using the differential positive rates, the best cut-off value to detect cats with ketoacidosis was 1·5 mmol/l for urine and 4 mmol/l for plasma. The sensitivity/specificity was 82/95 per cent for urine and 100/88 per cent for plasma, respectively.
C linical S ignificance : The urine and plasma ketone dip tests have a different diagnostic accuracy, and results have to be interpreted differently. Because of its high sensitivity, the plasma ketone dip test performs better than the urine ketone dip test to identify cats with impending or established ketoacidosis.     

Influence of a constant rate infusion of dexmedetomidine on cardiopulmonary function and recovery quality in isoflurane anaesthetized horses

ObjectiveTo investigate the influence of a dexmedetomidine constant rate infusion (CRI) in horses anaesthetized with isoflurane.Study designProspective, randomized, blinded, clinical study.AnimalsForty adult healthy horses (weight mean 491 ± SD 102 kg) undergoing elective surgery.MethodsAfter sedation [dexmedetomidine, 3.5 μg kg^?1 intravenously (IV)] and induction IV (midazolam 0.06 mg kg^?1, ketamine 2.2 mg kg^?1), anaesthesia was maintained with isoflurane in oxygen/air (FiO₂ 55–60%). Horses were ventilated and dobutamine was administered when hypoventilation [arterial partial pressure of CO₂ > 8.00 kPa (60 mmHg)] and hypotension [arterial pressure 70 mmHg] occurred respectively. During anaesthesia, horses were randomly allocated to receive a CRI of dexmedetomidine (1.75 μg kg^?1 hour^?1) (D) or saline (S). Monitoring included end-tidal isoflurane concentration, cardiopulmonary parameters, and need for dobutamine and additional ketamine. All horses received 0.875 μg kg^?1 dexmedetomidine IV for the recovery period. Age and weight of the horses, duration of anaesthesia, additional ketamine and dobutamine, cardiopulmonary data (anova), recovery scores (Wilcoxon Rank Sum Test), duration of recovery (t-test) and attempts to stand (Mann–Whitney test) were compared between groups. Significance was set at p < 0.05.ResultsHeart rate and arterial partial pressure of oxygen were significantly lower in group D compared to group S. An interaction between treatment and time was present for cardiac index, oxygen delivery index and systemic vascular resistance. End-tidal isoflurane concentration and heart rate significantly increased over time. Packed cell volume, systolic, diastolic and mean arterial pressure, arterial oxygen content, stroke volume index and systemic vascular resistance significantly decreased over time. Recovery scores were significantly better in group D, with fewer attempts to stand and significantly longer times to sternal position and first attempt to stand.Conclusions and clinical relevance A dexmedetomidine CRI produced limited cardiopulmonary effects, but significantly improved recovery quality.     

The perceived and actual diagnostic utility of veterinary cytological samples

O bjectives : To establish the proportion of cytology samples sent to a commercial veterinary laboratory that yields diagnostically useful information in the context of current use and perceptions of cytology.
M ethods : Nine hundred and forty-five cytology submissions were retrospectively collected and categorised according to diagnostic utility. A survey into the use and perceptions of cytology was distributed at the British Small Animal Veterinary Association Congress 2008.
R esults : A specific diagnosis was reached in 23·1 per cent of samples and a cytological diagnosis in 35·3 per cent. 22·4 per cent of samples yielded some useful information, but 19·2 per cent were unacceptable. Seventy-four participants in the survey took an average of 3·9 cytological samples per week, of which they examined 27·0 per cent in-house only, 21·6 per cent in-house before sending to an external laboratory and 51·4 per cent were sent externally without prior examination. "To obtain a definitive diagnosis" was the principal reason cited for performing cytology.
C linical S ignificance : Results suggest that cytology is underused and may be applied in an inappropriate context in the UK. It is hoped that illustrating the diagnostic outcome of samples received by a commercial laboratory will encourage increased, appropriate use of cytology.     

Comparison of thiopentone/guaifenesin, ketamine/guaifenesin and ketamine/midazolam for the induction of horses to be anaesthetised with isoflurane

Forty-eight horses subjected to elective surgery were randomly assigned to three groups of 16 horses. After premedication with 0.1 mg/kg acepromazine intramuscularly and 0.6 mg/kg xylazine intravenously, anaesthesia was induced either with 2 g thiopentone in 500 ml of a 10 per cent guaifenesin solution, given intravenously at a dose of 1 ml/kg (group TG), or with 100 mg/kg guaifenesin and 2.2 mg/kg ketamine given intravenously (group KG), or with 0.06 mg/kg midazolam, and 2.2 mg/kg ketamine given intravenously (group KM). Anaesthesia was maintained with isoflurane. The mean (sd) end tidal isoflurane concentration (per cent) needed to maintain a light surgical anaesthesia (stage III, plane 2) was significantly lower in group KM (0.91 [0.03]) than in groups TG (1.11 [0.03]) and KG (1.14 [0.03]). The mean (sd) arterial pressure (mmHg) was significantly lower in group KG (67.4 [2.07]) than in groups TC (75.6 [2.23]) and KM (81.0 [2.16]). There were no significant differences in the logarithm of the heart rate, recovery time or quality of recovery between the three induction groups. However, pronounced ataxia was observed in the horses of group KM, especially after periods of anaesthesia lasting less than 75 minutes.     

The effect of pre-anaesthetic medication on the incidence of cardiac arrhythmias during halothane anaesthesia in cats

Objective To compare the incidence of arrhythmias in cats receiving either acepromazine or diazepam for pre-anaesthetic medication prior to halothane anaesthesia.
Study design A blinded, randomized clinical study.
Animals Forty-six healthy cats undergoing surgery.
Methods Animals were allocated to one of two groups for pre-anaesthetic medication. Group 1 received diazepam (0.2 mg kg⁻¹). Group 2 received acepromazine (0.02 mg kg⁻¹). The trial drug was administered intramuscularly in combination with buprenorphine (0.01 mg kg⁻¹) 30 minutes prior to induction of anaesthesia with propofol (approximately 5 mg kg⁻¹). Anaesthesia was maintained using halothane: delivered concentration was 1–2% carried in oxygen and nitrous oxide via an endotracheal tube attached to an Ayre's T-piece (with Jackson-Rees modification) breathing system. The incidence of cardiac arrhythmias was determined by continuously monitoring the electrocardiogram from the time of induction until recovery occurred. Demographical group characteristics were compared using analysis of variance. The incidence of cardiac arrhythmias was compared by the Chi squared test. Statistical significance was set at the 5% level.
Results The two groups were similar in weight, age, length and type of procedure undertaken. The incidence of arrhythmias was the same in each group (3/23 cases) ( p = 1.0).
Conclusions The incidence of cardiac arrhythmias in this study did not appear to be influenced by the nature of pre-anaesthetic medication.
Clinical relevance The incidence of cardiac arrhythmias under halothane anaesthesia was 13% in this study. Acepromazine did not appear to exert an anti-arrhythmic effect. This may not be the case in a larger scale study.     

Aetiology and outcome in 90 cats presenting with dyspnoea in a referral population

O bjectives : Dyspnoea is an unspecific severe presenting sign, which can be life threatening and requires prompt treatment. Dyspnoeic cats often have significant underlying disease. Underlying aetiologies in cats that presented with dyspnoea were reviewed, and associations with patient signalment and outcome were investigated.
M ethods : The case records of 90 dyspnoeic cats were retrospectively reviewed and separated into different groups depending on aetiology (cardiac, respiratory, neoplastic and trauma). Duration of clinical signs, presentation, hospitalisation length and survival were analysed.
R esults : Cardiac (38 per cent), respiratory (32 per cent) and neoplastic (20 per cent) diseases were common causes of feline dyspnoea. Cats with respiratory causes had longer duration of clinical signs (P<0·001) before presentation. Cats with neoplasia were significantly older (P<0·001). No significant difference in respiratory rates was present between the groups (P = 0·154). High heart rates (P<0·001) and abnormalities on cardiac auscultation were more likely in the cardiac group.
Clinical Significance: Frequent causes of dyspnoea in cats were cardiac disease followed by respiratory causes and neoplastic conditions. Heart rate on presentation and presence of heart murmurs or gallops are useful to identify cardiac causes. Improved proportion surviving was found in the respiratory group (P = 0·027), whereas cats with neoplasia had the worst outcome.     

Inhalation anaesthesia for castration of newborn piglets: experiences with isoflurane and isoflurane/NO

The aim of this study was to evaluate the inhalation anaesthesia with isoflurane and isoflurane/N2O by mask induction for routine castration of piglets under 14 days of age. MATERIAL AND METHODS: Eighty-five male piglets aged between 4 and 12 days were used in a matched pair test. Two piglets of the same litter with the same weight were selected. One was castrated with, the other without anaesthesia. Induction was performed with either isoflurane (group ISO) or isoflurane/nitrous oxide (group ISO/N2O) in oxygen through a modified bain-breathing system. Induction time was 90 and 60 s for group ISO and group ISO/N2O, respectively. The disappearance of the palpebral reflex was recorded. The reaction of the piglets during castration was judged according to a scoring system separately for both testicles during skin incision and dissection of the spermatic cord. The scores were added and mean values were calculated. Total anaesthesia time, castration time and quality of recovery was recorded. Blood was collected from all piglets immediately after castration for measurement of ACTH and beta-endorphin values. Statistical analysis were performed by the Kruskal-Wallis test for nonparametric data and one-way anova (NCSS 2000, Kaysville, UT, USA). RESULTS: Induction of anaesthesia proved to be smooth in all cases. The palpebral reflex disappeared after 36.5 s in group ISO/N2O versus 51 s in group ISO. Mean castration scores were 0.6 in group ISO and 0 in group ISO/N2O, whereas 7.7 in piglets with no anaesthesia. These scores were significantly different. Mean anaesthesia time was 128 s (30-390) for group ISO and 123 s (70-220) for group ISO/N2O. No deaths occurred. The differences in the levels of ACTH and beta-endorphins in the blood plasma in the different groups showed no statistical difference. DISCUSSION: This study demonstrates that isoflurane or isoflurane/N2O anaesthesia by mask induction proves to be a safe, short and reliable method in piglets undergoing castration. Reaction to the castration procedure were significantly reduced. Stress hormone values were not different between the groups because of a large individual difference.     

Outcome following removal of canine spindle cell tumours in first opinion practice: 104 cases

O bjectives : To define the outcome of a cohort of canine patients with a histological diagnosis of spindle cell tumour of soft tissue managed solely by surgery in first opinion practice.
M ethods : Clinical details of 104 spindle cell sarcomas submitted to Finn Pathologists during the year 2000 were reviewed. Questionnaires were sent to the submitting veterinarians, requesting details about the tumour, surgery performed and ultimate outcome of the patient.
R esults : The method of surgical resection was described as marginal in 45 dogs (44·2 per cent). Excision margins of 3 cm or more were described in less than 10 per cent of cases. Tumours recurred locally in 29 dogs (27·9 per cent). Eighteen dogs (21·7 per cent) died of tumour-related causes. Most deaths were unrelated to sarcoma (50 dogs, 60·2 per cent) or unknown (15 dogs, 18 per cent). The median survival time was 1013 days. Tumour size, location or degree of surgical resection were not significantly related to survival or tumour recurrence. A palpable assessment of tumour invasion into underlying tissues was significantly associated with decreased disease-free interval (P<0·0001) and survival time (P = 0·0070).
C linical S ignificance : The results of this retrospective study indicate that many spindle cell tumours managed in first opinion practice exhibit a low-grade biological behaviour and may respond well to more conservative surgery than current recommendations advise.     

Low flow anaesthesia with isoflurane in the dog

The aim of the present study was to compare the safety of two low flow (LF) regimes [fresh gas flow (FGF) 20 ml/kg/min (group 2) and 14 ml/kg/min (group 3)] with the high flow (HF) technique (FGF 50 ml/kg/min; group 1) of isoflurane anaesthesia. Data were gathered from ninety dogs assigned for surgery under general anaesthesia with an expected duration of 75 minutes or longer. All dogs had an anaesthetic induction with 0,6 mg/kg I-methadone (maximum 25 mg) and 1 mg/kg diazepam (maximum 25 mg) i.v. Anaesthesia was maintained with isoflurane in a mixture of 50% O2 and 50% N2O as carrier gases, with controlled ventilation. The Monitoring included electrocardiogramm, body temperature, the temperature of in- and exspired gases, arterial oxygen saturation, arterial blood pressure as well as a continuous monitoring of inhaled and exhaled gas concentrations (O2, N2O, CO2, isoflurane). The consumption of isoflurane and carrier gases as well as the recovery times were evaluated for the three groups. The inspired oxygen concentrations always ranged above the minimum value of 30 Vol.-% during low flow anaesthesia. The arterial oxygen saturation ranged between 92-98%, the end tidal concentration of CO2 between 35 and 45 mmHg. Heart rate and arterial blood pressure were within normal limits. Recovery time was significantly shorter after LF than after HF anaesthesia. The highest decrease in body temperature occurred in the HF group 1 because of a significantly lower anaesthetic gas temperature. Despite this, LF anaesthesia resulted in a reduced consumption of carrier gases and volatiles. In conclusion, low flow anaesthesia with isoflurane is a safe technique and offers substantial economic advantages over high flow techniques and is moreover better tolerated by the patients.     

A comparison of the pharmacodynamic effects of intravenous ketamine–xylazine with alfaxalone in mute swans (Cygnus olor) presenting at a wildlife veterinary hospital

ObjectiveTo compare effects of intravenous (IV) alfaxalone with ketamine–xylazine combination on anaesthetic induction, recovery and cardiopulmonary variables in mute swans.Study designRandomized, controlled, clinical study.AnimalsA group of 58 mute swans.MethodsSwans were given either alfaxalone (10 mg kg^–1; group A) or a combination of ketamine (12.5 mg kg^–1) and xylazine (0.28 mg kg^–1) (group KX) IV. Heart and respiratory rates, end-tidal carbon dioxide and peripheral haemoglobin oxygen saturation were recorded at 5 minute intervals during anaesthesia. Time from anaesthetic induction to intubation, from cessation of isoflurane to extubation, to lifting head, sternal recumbency and absence of head/neck ataxia were recorded. Anaesthetic and recovery quality were scored (1 = very poor; 5 = excellent). Data are presented as median (interquartile range). Significance was set at p < 0.05.ResultsIn group A, 44% (12/27) of swans required mechanical ventilation for 2–14 minutes versus 3.2% (1/31) of swans in group KX (p = 0.0002). Heart rate was higher in group A than in group KX [146 (127–168) versus 65.5 (56–78) beats minute^–1, respectively; p < 0.0001]. The isoflurane concentration required to maintain anaesthesia was higher in group A than in group KX [2.5% (2.0–3.0%) versus 1.5% (1.0–2.0%), respectively; p = 0.0001]. Time from cessation of isoflurane administration to lifting head was significantly longer in group A than in group KX [12 (9–17) versus 6 (4–7.75) minutes, respectively; p < 0.0001]. Anaesthesia quality scores were significantly better in group KX than in group A [4 (4–5) versus 4 (3–4), respectively; p = 0.0011], as were recovery scores [4 (3–5) versus 2 (2–3), respectively; p = 0.0005].Conclusions and clinical relevanceAlfaxalone is a suitable anaesthetic induction agent for use in mute swans. There is a greater incidence of postinduction apnoea and a higher incidence of agitation on recovery with alfaxalone than with ketamine–xylazine.     

Subcutaneous pre-anaesthetic medication with acepromazine–buprenorphine is effective as and less painful than the intramuscular route

O bjectives : To compare reaction to injection, sedation and propofol induction dose in dogs receiving acepromazine–buprenorphine pre-anaesthetic medication by the intramuscular or subcutaneous routes.
M ethods : Fifty-two client owned dogs of American Society of Anesthesiologists grade I or II anaesthetised for diagnostic imaging. Dogs were randomly assigned to receive acepromazine 0·03 mg/kg and buprenorphine 0·02 mg/kg either intramuscular or subcutaneous. Reaction to injection was scored. Sedation was compared before and one hour after pre-anaesthetic medication. Propofol was administered in 1 mg/kg incremental injections until tracheal intubation was achieved. Total propofol dose was recorded.
R esults : Reaction to injection was significantly greater (P=0·009) in the intramuscular group compared to the subcutaneous group. Sedation scores were not significantly different (P=0·523) between the intramuscular and the subcutaneous group. There was no statistically significant difference in propofol dose for induction (P=0·7).
Clinical Significance: Acepromazine–buprenorphine pre-anaesthetic medication provides a similar degree of sedation whether administered by the intramuscular or subcutaneous route. The intramuscular route is more painful compared to the subcutaneous route.     

Acquired urinary incontinence in bitches: its incidence and relationship to neutering practices

A five-year cohort study was conducted on bitches chosen by a sample of 233 randomly selected practising veterinary surgeons in the UK, to estimate the incidence of acquired urinary incontinence (AUI) in neutered and entire animals, and to investigate possible risk factors associated with neutering practices. Information was collected using questionnaires, and data on 809 bitches, of which 22 developed AUI, were obtained. The estimated incidence rates in neutered and entire animals were 0·0174 and 0·0022 per animal-year, respectively (95 per cent confidence intervals: 0·0110, 0·0275 and 0·0009, 0·0058, respectively). The relative risk, neutered vs entire, was 7·8 (95 per cent confidence interval: 2·6, 31·5). The attributable proportion_exposed and population attributable proportion were 87·1 per cent and 63·1 per cent (95 per cent confidence intervals: 61·9 per cent, 95·6 per cent, and 28·3 per cent, 88·5 per cent, respectively). An increased risk, significant at the conventional 5 per cent level, was not demonstrated in animals neutered before, vs after, first heat (relative risk: 3·9, 95 per cent confidence interval: 0·8, 10·4), although the result was significant at the 10 per cent level. Removal of the cervix was not shown to be a risk factor in neutered dogs.