RESUMEN

A cytological grading system for canine mast cell tumors (MCTs) has been developed, but its integration into clinical routine has been hindered due to its diagnostic limitations. The aim of this study was to assess the prognostic value of Ki-67 and argyrophilic nucleolar organizing region (AgNOR) markers in cytological MCT samples and to determine cut-off values for these markers in correlation with histopathological grading. Cytological samples were collected prior to surgical excision, and histopathological samples were obtained postsurgery from 45 dogs diagnosed with cutaneous mast cell tumors (MCTs). The cytological specimens were classified using a two-tier grading system, and their Ki-67 (average immunopositive nuclei per 100 cells) and AgNOR (average AgNOR counts per 100 nuclei) signaling was assessed. Through receiver operating characteristic (ROC) analysis, cut-off values for Ki-67 and Ki-67 × AgNOR were determined to better align with histopathological grading (classified as low or high grade according to Kiupel's scoring system). Without the inclusion of proliferative markers, there was a 73% agreement between cytological and histopathological grading. The prediction of histopathological grade was slightly more accurate when assessing Ki-67 and Ki-67 × AgNOR signaling in cytological specimens (75% and 80%, respectively) compared to the initial cytological grading. The cytological assessment of canine MCTs proves beneficial for the initial evaluation, and the incorporation of the evaluation of Ki-67 and AgNOR markers may assist in identifying diagnostically highly malignant MCTs.

RESUMEN

The aim of this prospective, non-randomized study was to evaluate the effect of nine different premedication medications on the incidence of gastroesophageal reflux (GOR) in anesthetized dogs. Two hundred and seventy dogs undergoing non-intrathoracic, non-intrabdominal elective surgeries or invasive diagnostic procedures were included in the study, and were allocated into nine groups (30 dogs/group) defined by the type of premedication administered. Premedication consisted of dexmedetomidine with either morphine, pethidine or butorphanol, acepromazine with either one of the three opioids or midazolam with one of the above-mentioned opioids. Anesthesia was induced with propofol and maintained with isoflurane in oxygen. Esophageal pH was measured with the use of a pH-meter electrode and a pH-value less than 4 and over 7.5 was considered to be GOR. The study revealed that 119/270 (44.1%) dogs experienced a reflux episode during anesthesia. The incidence of reflux did not differ among groups (p = 0.117). In group AB the dogs refluxed within 10 min of the beginning of pH-measurements, in comparison with group DB in which dogs refluxed within 30 min (p = 0.029). Invasive diagnostic procedures had a lower incidence of GOR in comparison to castrations (p = 0.09). The outcome of the study suggests that none of the opioids used increased the incidence of GOR in anesthetized dogs.

RESUMEN

Mast cell tumor (MCT) is a frequent cutaneous tumor in dogs, with a variable biological behavior. Studies correlate cytologic and histopathologic features of MCTs with their biological behavior, prognosis, and response to treatment. The use of preoperative opioids is common in canine patients undergoing surgical removal of these tumors. Certain opioids can induce or downregulate mast cell degranulation and influence cancer progression. The aim of the present study was to investigate whether the administration of morphine or butorphanol during surgical excision of canine cutaneous MCTs affects their cytologic and histopathologic appearance, thus influencing cytologic and histopathologic grading. This was a prospective, blinded, randomized, cohort clinical study. Forty-five dogs with cutaneous MCTs were randomly allocated into three groups according to preanaesthetic medication: dexmedetomidine combined with morphine (group M) or butorphanol (group B) or normal saline (group C). Cytologic specimens and histopathologic samples were obtained both prior to and after surgery. Samples were graded according to Kiupel's and Patnaik's systems, examined immunohistochemically for Ki-67 protein (Ki-67) and c-kit proto-oncogene product (KIT) expression, and histochemically for argyrophilic nucleolar organizing regions (AgNORs). Based on both Kiupel's and Patnaik's systems, no statistically significant differences were noted concerning the number of cases with grading discrepancies in grades allocated prior to versus after surgery among the groups. The same applied for cytological grading and immunohistochemical and histochemical evaluation. It seems that administration of morphine or butorphanol as part of the preanesthetic medication for surgical removal of canine cutaneous mast cell tumors does not influence histopathologic and cytologic grading of MCTs.

RESUMEN

This study aimed to investigate the effect of three different preoperative fasting regimens on the incidence of gastro-oesophageal reflux (GOR) in dogs under general anaesthesia. Ninety dogs undergoing non-abdominal and non-thoracic elective surgery were included in the study and equally allocated to three groups. Dogs received canned food providing half the daily resting energy requirements (RER) 3 h prior to premedication (group 3H), a quarter of the daily RER 3 h before premedication (group 3Q), and half the daily RER 12 h before premedication (group 12H). The animals were premedicated with acepromazine and pethidine, anaesthesia was induced with propofol and maintained with isoflurane vaporised in oxygen. Oesophageal pH was monitored throughout anaesthesia. Demographic and surgery-related parameters were not different among groups. The incidence of GOR was 11/30 in group 3H (36.7%), 9/30 in group 3Q (30.0%) and 5/30 in group 12H (16.7%), which was not statistically different (p = 0.262). Reduction of the amount of the preoperative meal from half to a quarter of the daily RER did not reduce the incidence of GOR but resulted in a lower oesophageal pH (p = 0.003). The results of this study suggest that the administration of a meal 3 h before anaesthesia does not have any beneficial effect in the reduction of GOR incidence in dogs compared to the administration of a meal 12 h before anaesthesia.

RESUMEN

OBJECTIVES: The emergence and spread of transferable ß-lactamases among Enterobacteriaceae is a major problem both to human and veterinary medicine and is an important contributing factor to the development of multidrug-resistant bacterial isolates. In the present study, whole-genome sequencing of a Klebsiella pneumoniae isolate (LKP817909) resistant to first- and second-generation cephalosporins and non-susceptible to fluoroquinolones, isolated from a urine sample of a hospitalised dog, was performed. METHODS: Genome sequencing was performed on an Illumina MiniSeq Sequencing System. Multilocus sequence typing (MLST) was performed using a BLAST-based approach, whereas antimicrobial resistance genes and plasmid replicons were identified by ResFinder and PlasmidFinder, respectively. The Rapid Annotation using Subsystem Technology (RAST) server v.2.0 was used for genome annotation. RESULTS: Data analyses revealed the complete resistome of isolate LKP817909, which included the cefotaximase-München-11 (CTX-M-11) extended-spectrum ß-lactamase together with 11 other resistance genes. Ten resistance genes were located on plasmids and two on the chromosome. CONCLUSIONS: To the best of our knowledge, this is the first detection of a CTX-M-11-producing K. pneumoniae isolated from a canine. The whole genome sequence of the isolate has been deposited at GenBank to serve as a future reference.

Asunto(s)

RESUMEN

OBJECTIVE: To test the efficacy of intraoperative intrafragmentary administration of bupivacaine (haematoma block) in controlling postoperative pain in dogs undergoing osteosynthesis of long-bone isolated diaphyseal fractures. STUDY DESIGN: Randomized, 'blinded', placebo-controlled, prospective study. ANIMALS: A total of 23 client-owned dogs with isolated long-bone fractures. METHODS: Dogs were allocated randomly to two groups: bupivacaine group (B) or placebo group (P). Group B dogs (n = 11) were administered an intraoperative intrafragmentary injection of 0.5% bupivacaine (1.1 mg kg-1) just before fracture fixation, whereas group P dogs (n = 12) were administered normal saline. Postoperative pain evaluations using the University of Melbourne Pain Scale (UMPS) and algometer were performed upon arrival to the recovery room and 1, 2, 4, 6, 8, 20 and 32 hours later. Algometer measurements were performed on: the incision site, a healthy region near the fracture line and the contralateral healthy limb. When the pain score exceeded 14 points in the UMPS, rescue analgesia was administered. The time-standardised area under the curve (AUCst) was used to compare UMPS scores and mechanical pain thresholds between the two groups. RESULTS: None of the group B dogs required rescue analgesia, whereas eight of the 12 group P dogs did (p = 0.001). The pain threshold AUCst at the incision line was higher in group B [16.3 (2.9-41.6) N] than in group P [5.6 (2.5-17.4) N] (p = 0.029). The mean UMPS score AUCst was lower in group B (3.7 ± 1.8) than in group P (9.4 ± 4.6) (p = 0.016). In a small number of animals of both groups that were evaluated radiologically, adequate bone healing was noted. CONCLUSIONS AND CLINICAL RELEVANCE: An intraoperative bupivacaine haematoma block is a simple, quick and effective method that can be used to aid in postoperative pain control in dogs submitted to long-bone osteosynthesis.

Asunto(s)

RESUMEN

OBJECTIVE: The aim of this study was to investigate whether an increased frequency of gastro-oesophageal reflux (GOR) is more common in large-sized, deep-chested dogs undergoing spinal surgery in sternal recumbency than in small-sized, barrelchested dogs. STUDY DESIGN: Prospective, cohort study. ANIMALS: Nineteen small-sized, barrel-chested dogs (group B) and 26 large-sized, deep-chested dogs (group D). METHODS: All animals were premedicated with intramuscular (IM) acepromazine (0.05 mg kg-1) and pethidine (3 mg kg-1) IM. Anaesthesia was induced with intravenous sodium thiopental and maintained with halothane in oxygen. Lower oesophageal pH was monitored continuously after induction of anaesthesia. Gastro-oesophageal reflux was considered to have occurred whenever pH values > 7.5 or < 4 were recorded. If GOR was detected during anaesthesia, measures were taken to avoid aspiration of gastric contents into the lungs and to prevent the development of oesophagitis/oesophageal stricture. RESULTS: The frequency of GOR during anaesthesia was significantly higher in group D (6/26 dogs; 23.07%) than in group B (0/19 dogs; 0%) (p = 0.032). Signs indicative of aspiration pneumonia, oesophagitis or oesophageal stricture were not reported in any of the GOR cases. CONCLUSIONS AND CLINICAL RELEVANCE: In large-sized, deep-chested dogs undergoing spinal surgery in sternal recumbency, it would seem prudent to consider measures aimed at preventing GOR and its potentially devastating consequences (oesophagitis/oesophageal stricture, aspiration pneumonia).

Asunto(s)

RESUMEN

Accumulation of urine in the pleural space secondary to uroperitoneum with no disruption of the diaphragm appears to be a rare pathological condition. A 2 yr old male mixed-breed dog was referred with dyspnea and abdominal pain after a road traffic accident. Plain radiographs demonstrated pleural effusion and reduced serosal detail in the abdominal cavity that was compatible with fluid accumulation. Retrograde urethrography revealed a pelvic urethra rupture. Biochemical analysis of the pleural and abdominal fluid confirmed the diagnosis of urothorax and uroperitoneum. The dog underwent a prepubic urethrostomy and intensive care management. The dog was reported to be in good health after a follow up time of 10 mo. To the authors' knowledge, this is the first reported case of urothorax associated with uroperitoneum with no detectable defects of the diaphragm in a dog.

Asunto(s)

RESUMEN

A 4-mo-old red fox (Vulpes vulpes) was found recumbent after a vehicular accident. Radiology revealed several limb fractures and the fox underwent surgery after 24 hr of initial stabilization. Premedication consisted of dexmedetomidine and morphine. Anesthesia was induced with ketamine and midazolam and maintained with isoflurane. Lidocaine, bupivacaine, and morphine were administered epidurally and further analgesia was provided with meloxicam. The heart rate and respiratory rate of the fox remained stable during surgery and, except for a mild hypothermia, the recovery from anesthesia was uneventful. The postoperative pain scores were low and the animal was transported to a rehabilitation facility and eventually released to the wild. The low pain scores postoperatively should be attributed to the successful application of epidural anesthesia and analgesia.

Asunto(s)

RESUMEN

OBJECTIVE: To investigate the potential association of increased blood progesterone (P4 ) concentrations and/or late pregnancy with the incidence of gastro-oesophageal reflux (GOR), in healthy bitches undergoing ovariohysterectomy under general anaesthesia during anoestrus or dioestrus or during the second half of pregnancy. STUDY DESIGN: Prospective observational study. ANIMALS: Ninety-four healthy, female, dogs, aged 1-8 years presented for elective ovariohysterectomy. METHODS: Non-pregnant animals were classified into group A (anoestrus) (n = 35) if blood P4 concentration was sufficiently low or group D (dioestrus) (n = 26) if blood P4 concentration was sufficiently high. All animals in the second half of pregnancy were classified into group P (n = 33). Acepromazine (0.05 mg kg(-1) ) was administered intramuscularly as preanaesthetic medication, and sodium thiopental (10 mg kg(-1) , with additional doses if needed) was administered intravenously (IV) for induction of anaesthesia. After endotracheal intubation, halothane (1.1-1.3% end-tidal concentration) in oxygen was used for maintenance of anaesthesia. Lower oesophageal pH was monitored continuously throughout surgery using a pH-measuring probe. Reflux was considered to have occurred whenever pH values of >7.5 (alkaline reflux) or <4 (acid reflux) were recorded. On completion of surgery, carprofen (4 mg kg(-1) ) was administered IV. Further administration of analgesics post-operatively was dictated by visual analogue scale pain scoring. RESULT: Acid GOR was observed in five of 26 dogs in group D, six of 35 group A, and 12 of 33 group P (p = 0.152). The incidence of GOR in group P approached statistical significance and was higher than the incidence in the combined group A + D (one sided p = 0.044, two sided p = 0.077). CONCLUSIONS: In dogs undergoing ovariohysterectomy, GOR during anaesthesia occurs with a high incidence in dogs in the second half of pregnancy compared to non-pregnant animals during anoestrus or dioestrus. CLINICAL RELEVANCE: Measures could be taken in such cases to avoid the consequences of potential reflux.

Asunto(s)

RESUMEN

Although left- or right-sided pneumonectomy is tolerated by normal dogs, complications impacting the respiratory, cardiovascular, and gastrointestinal systems are not uncommon. Pneumonectomy in dogs results in secondary changes in the remaining lung, which include: decreased compliance and vital capacity; and increased pulmonary vascular resistance potentially leading to right ventricular hypertrophy. Such alterations make the anesthetic management of an animal with one lung particularly challenging. This report describes a dog with a history of left pneumonectomy due to Aspergillus fumigatus pneumonia 3 yr before presentation. The dog presented with a vaginal wall prolapse, and surgical resection of the protruding vaginal wall, ovariectomy, and prophylactic gastropexy were performed. Anesthesia was induced with midazolam, fentanyl, and propofol and was maintained with isoflurane using intermittent positive pressure ventilation and a constant rate infusion of fentanyl. Epidural anesthesia was also used. Recovery and postoperative management were uncomplicated. Intensive hemodynamic and respiratory monitoring and appropriate response and treatment of any detected abnormalities, taking into consideration the pathophysiologic alterations occurring in a pneumonectomized animal, are required for successful perianesthetic management.

Asunto(s)

RESUMEN

Remifentanil is a synthetic opioid with direct action on µ opioid receptors. It has an ultrashort duration of action, and its elimination is independent of hepatic or renal function. The anesthetic management of five dogs with nonuniform liver disease and requiring liver biopsy via celiotomy is described. Remifentanil and isoflurane were used for induction and maintenance of anesthesia. Intraoperative analgesia was provided by a constant rate infusion of remifentanil. Remifentanil, in combination with isoflurane, was safely and successfully used in five cases for the balanced anesthesia of dogs with hepatic diseases requiring liver biopsy via celiotomy.

Asunto(s)

RESUMEN

The enantiomeric naphthoquinones alkannins and shikonins (A/S) have been established as potent wound healing agents. The purpose of this study was to evaluate the effectiveness of an A/S based ointment for humans on second intention wound healing in the dog, as compared to wound flushing with Lactated Ringer's solution (LRS). Ten mixed breed dogs, aged 2 to 5 y, were used. One 2.5 × 2.5 cm full-thickness skin defect was created on the lateral aspect of each arm for subjective evaluation, laser-Doppler flowmetry (LDF), and planimetry. Additionally, 3 matching 2 × 2 cm wounds were created on opposite sides of the dorsal midline for histologic evaluation. Wounds were treated once daily with the A/S based ointment on the right side and by flushing with LRS on the left until healed (about 20 d). During the healing process, tissue perfusion (mean LDF value) was found to be significantly higher on the side treated with the A/S based ointment compared with the LRS-treated side. Histologically, angiogenesis (on days 4 and 11), collagen production score (on days 4, 11, and 20), and epithelial thickness score (on day 11) were significantly higher in the wounds treated with the A/S based ointment. Wound size, as evaluated by planimetry, decreased significantly from day 0 to day 20 on both sides, but no significant differences were found between the A/S based ointment and LRS-treated wounds.

Asunto(s)

RESUMEN

BACKGROUND: The healing efficacy of isohexenylnaphthazarins (IHN) has been well proved on chronic or contaminated wounds. OBJECTIVE: To evaluate the wound healing activity of an experimental ointment containing IHN on acute and noncontaminated wounds in dogs. METHODS: In each of six beagle dogs, four full-thickness skin defects were created bilaterally: one 2 x 2 cm defect on the lateral aspect of each arm for subjective evaluation, laser Doppler flowmetry (LDF), and planimetry and three 1.5 x 1.5 cm defects on opposite sides of the dorsal midline for histologic evaluation. Wounds on the left were treated with an ointment based on IHN and on the right with another based on petroleum jelly (Vaseline) and beeswax. RESULTS: Wound size decreased significantly in both sides. The significantly increased percentage of epithelialization was higher (p = .0274) in the petroleum jelly-treated wounds on day 20. Tissue perfusion (LDF) increased significantly bilaterally in the center of the wound but only in the IHN-treated side cranial to the wound. Histologically, angiogenesis was significantly higher (p = .0431) on day 5 in the IHN-treated wounds compared with the petroleum jelly-treated wounds. Collagen production increased significantly bilaterally. CONCLUSION: The IHN-based ointment promoted some of the proliferative processes, but it did not enhance the overall wound healing of acute, surgically created wounds in dogs.

Asunto(s)

RESUMEN

OBJECTIVE: To investigate the potential effect of increased blood progesterone (P(4)) and oestradiol-17beta (E(2)) concentrations on the barrier pressure (BrP) and the incidence of gastro-oesophageal reflux (GOR) in female dogs under general anaesthesia. STUDY DESIGN: Prospective, blinded experimental trial. ANIMALS: Seven female, adult, healthy dogs weighing 14-21 kg and aged 1-7 years. METHODS: Each of the animals was studied under the influence of high blood E(2) and basal P(4) (study O), basal E(2) and high P(4) (study P) and basal E(2) and P(4) (study C) concentrations. Animals were premedicated with acepromazine and anaesthesia was induced with thiopental and maintained with halothane. Lower oesophageal pH was monitored continuously for 1 hour after induction. GOR was defined as oesophageal pH >7.5 or <4. Manometry of the posterior oesophageal sphincter (POS) was then performed using the slow pull-through technique. RESULTS: Acid GOR was detected in only one animal of study O. The three studies did not differ significantly in GOR. Mean BrP was 11.2 (study O), 9.1 (study P) and 11.6 mmHg (study C). No significant differences were detected with respect to mean BrP, intra-gastric pressure and POS pressure. CONCLUSIONS: It is unlikely that the increased concentrations of E(2) or P(4) during the normal ovarian cycle influence the functional efficiency of the POS as a major barrier to GOR in healthy, female dogs under general anaesthesia. CLINICAL RELEVANCE: The fact that female dogs undergoing obstetrical surgery represented a substantial sub-group of the animals which developed postoperative benign oesophageal stricture, should probably not be attributed to the effects of increased concentrations of female sex steroid hormones.

Asunto(s)

RESUMEN

A blind, placebo-controlled clinical trial was performed to evaluate the postoperative analgesic effect of preoperative infiltration of the incision site with bupivacaine in dogs undergoing celiotomy. Sixty dogs were randomly allocated into four groups: preoperative bupivacaine, postoperative bupivacaine, preoperative saline, and postoperative saline. All dogs were premedicated with acepromazine and meperidine; then they were anesthetized with thiopentone and isoflurane. Each group received either bupivacaine or normal saline before midline incision or just before skin closure. After surgery, pain scores were assigned using a numerical rating scale. Preoperative bupivacaine was associated with significantly lower pain scores and a significantly lower need for opioid administration. The authors conclude that a preoperative incisional block with bupivacaine seems to be a useful adjunct for controlling pain after celiotomy in dogs.

Asunto(s)

RESUMEN

OBJECTIVE: To evaluate the effect of pre- and intraoperatively administered magnesium sulphate (MgSO(4)) on the induction dose of thiopental and of halothane for maintenance of anaesthesia in dogs undergoing ovariohysterectomy (OHE). STUDY DESIGN: Prospective, double-blind, randomized, placebo-controlled study. ANIMALS: Forty-six healthy, ASA physical status 1 dogs, scheduled for elective OHE. METHODS: The dogs were randomly assigned to receive a bolus of 50 mg kg(-1) MgSO(4) intravenously (IV), just before induction of anaesthesia, followed by a constant rate infusion (CRI) of 12 mg kg(-1) hour(-1) MgSO(4) intraoperatively (group Mg, n = 27) or a placebo bolus and CRI of 0.9% sodium chloride (NaCl) (group C, n = 19), approximately 30 minutes after premedication with acepromazine (0.05 mg kg(-1), intramuscularly, IM) and carprofen (4 mg kg(-1), subcutaneously, SC). Anaesthesia was induced with thiopental administered to effect and maintained with halothane in oxygen. End-tidal halothane (ET(hal)) was adjusted to achieve adequate depth of anaesthesia. Blood samples were obtained pre- and postoperatively for measurement of total serum magnesium concentration. RESULTS: The mean dose of thiopental was statistically lower (p < 0.0005) and the mean standardized ET(hal) concentration and end-tidal carbon dioxide partial pressure (Pe'CO(2)) areas under the curve were statistically smaller (p < 0.0005 and 0.014 respectively) in group Mg. Postoperatively the mean total serum magnesium concentration was statistically higher than the preoperative value (p < 0.0005) in group Mg, but not in group C. Nausea, associated with the MgSO(4) bolus injection, was observed in six dogs in group Mg, two of which vomited prior to induction of anaesthesia. CONCLUSIONS AND CLINICAL RELEVANCE: Magnesium sulphate administration reduced the induction dose of thiopental and ET(hal) concentration for maintenance of anaesthesia in dogs undergoing OHE. Observed side effects were nausea and vomiting.

Asunto(s)

RESUMEN

The laryngeal mask airway (LMA) has been used in various animal species anesthetized for the purpose of device evaluation, but the device has not been evaluated in rabbits during surgery. The authors tested the feasibility and potential advantages of using the LMA in 50 rabbits undergoing surgery under spontaneous-breathing inhalational anesthesia, focusing mainly on the technique of insertion and its efficacy. The LMA was easily inserted and no air leakage at the larynx was detected. Although four rabbits developed lingual cyanosis, this was reversible and most likely due to lingual vascular compression by the LMA. The authors conclude that the LMA is an attractive alternative to endotracheal intubation, as the mask can be inserted easily and rapidly and its correct placement is easily confirmed.

Asunto(s)

RESUMEN

BACKGROUND: Extradural lidocaine exerts several adverse effects which are seldom fatal. While cardiac arrest following extradural lidocaine injection has been reported in human beings, it has not hitherto been reported in dogs. OBSERVATIONS: The emergency management of a dog with complete urethral obstruction is described. We intended to perform vaginoscopy and cystostomy under extradural lidocaine anaesthesia, but cardiac asystole occurred a few minutes after injection. Resuscitation was successful. About 20 minutes later cardiac arrest recurred, and was treated successfully. The dog remained hypothermic for approximately 7 hours. Complete recovery without neurological deficit occurred the next day and the dog remained normal for at least 3 months. The probable cause of the problem was cranial lidocaine dispersion causing a drop in cardiac preload and cardiac arrest. The successful neurological outcome was attributed to early diagnosis and effective treatment. Hypothermia may have conferred cerebral protection during ischemia. CONCLUSIONS: Extradural local anaesthetic administration is not without risk and the technique should be tailored to individual animals. Constant monitoring is required to detect potentially fatal complications and increase the likelihood of successful outcome.

Asunto(s)