Intrasynovial autograft for reconstruction of chronic large rotator cuff tears in a rabbit model: biomechanical, computed tomography, and histological results.

BACKGROUND: Rotator cuff (RC) tears are a common cause of shoulder dysfunction and pain, posing significant challenges for orthopedic surgeons. Grafts have been proposed as a solution to augment or bridge torn tendons, but optimal clinical outcomes are not always achieved due to poor graft integration, suboptimal mechanical properties, and immunological reactions. The aim of this study was to investigate the biomechanical, CT and histological results of RC reconstruction using an intrasynovial tendon autograft, in a chronic large tear subscapularis rabbit model. METHODS: Twenty-six adult male Zealand white rabbits were used in this study. Large defects in the subscapularis tendons were produced bilaterally in 20 rabbits. After 6 weeks, secondary procedures were performed to the right shoulder of the rabbits, which were reconstructed with an intrasynovial interposition autograft (graft group). The left shoulder did not undergo any further treatment (defect group). The specimens were randomly divided into two equal time groups and underwent biomechanical testing, CT analysis, and histological evaluation at 6, and 12 weeks after reconstruction. In addition, 6 rabbits that were not operated, were used as a control group. RESULTS: At 12 weeks post-repair, the graft group exhibited a significant increase in ultimate failure load compared to the defect group (p < 0.05). Furthermore, the 12-week graft group demonstrated comparable stiffness to that of the control group. CT analysis indicated no significant progression of intramuscular fat accumulation in both graft groups, in contrast to the 12-week defect group when compared to the control group. Finally, histological evaluation revealed a gradual integration of the graft with the host tissue at 12 weeks. CONCLUSION: Our study suggests that intrasynovial flexor tendon autografts hold promise as an effective interposition graft for the reconstruction of chronic large RC tears, as they improve the biomechanical and biological properties of the repaired tendon. Nonetheless, further investigations in preclinical large animal models are warranted to validate and extrapolate these findings to human studies.

Repair of chronic and large rotator cuff tears using extra-synovial autografts: An experimental study in rabbits.

Purpose: To investigate whether and how extra-synovial autografts can enhance the reconstruction of chronic and large rotator cuff tears in a rabbit subscapularis model. Methods: Twenty rabbits were used to create a large subscapularis tear bilaterally. Six weeks later, the right shoulder of each rabbit was operated to repair the tear with an extra-synovial autograft, whereas the left shoulder did not undergo any surgery. At 6 and 12 weeks after the second procedure, the specimens underwent biomechanical and histological evaluation. Six more rabbits were used only as a normal reference. Results: Biomechanical evaluation demonstrated that the ultimate load to failure of the Graft group (184.1 ± 35.7 N) was significantly higher (p = 0.04) than that of the Defect group (144.5 ± 32.2 N) at 12 weeks after repair, rising to 76% of the normal subscapularis tendon tensile strength. Histological analysis revealed an enhanced healing environment with neoangiogenesis and decreased inflammatory response at the repair site. Moreover, the tendon maturing score of the Graft group increased substantially from 6 (15.8 ± 0.9) to 12 (23.1 ± 0.6) weeks after repair (p = 0.01). Conclusion: In vivo data support the efficacy of extra-synovial autograft interposition in repairing chronic and large rotator cuff tears in a rabbit subscapularis model. The autografts were capable of enhancing the biomechanical properties of the repaired tendons, as evidenced by increased tensile strength, and forming new connective tissue simulating a fibrocartilage zone, as revealed by histological evaluation. Level of Evidence: N/A.

Isoflurane treatment for refractory and super-refractory status epilepticus in dogs.

Introduction: Resistant epileptic episodes, such as refractory status epilepticus (RSE) and super-refractory status epilepticus (SRSE), are neurological emergencies that require immediate medical treatment. Although inhalational anesthetics, such as isoflurane (ISO), have been proposed as a means of seizure control in dogs, there is currently a lack of both experimental and clinical studies on this subject. Study design: This is a retrospective clinical study. Methods: Records of dogs that received ISO for the management of RSE and SRSE during their intensive care unit (ICU) hospitalization at the Companion Animal Clinic of the Aristotle University of Thessaloniki were included in the present study. The study period spanned from February 2013 to March 2023. Dogs were identified as responders (R) when RSE/SRSE ceased after ISO administration, and the dogs were successfully discharged from the ICU after ISO discontinuation. Dogs were identified as non-responders (NR) when RSE/SRSE ceased after ISO administration, but RSE/SRSE reoccurred after ISO discontinuation. Additional data about the number and time of ISO cycles, the time of ICU hospitalization, the side effects of ISO administration, and an additional administration of antiepileptic drugs (AEDs) and anesthetic drugs were also recorded. Results: A total of 20 dogs with 26 recorded RSE/SRSE episodes and 26 anesthetic cycles with ISO were included in the present study. The clinical termination of seizure activity was achieved 100% (26/26) in all episodes. In 73.1% (19/26) of the episodes, ISO administration resulted in successful RSE/SRSE treatment. Poor outcome was recorded in 26.9% (7/26) of the episodes because RSE/SRSE reoccurred after ISO discontinuation, and the dogs were euthanatized or died due to cardiac arrest. Inspiratory ISO ranged between 0.5 and 4.0%. The median time of the anesthetic cycles with ISO was 12.67 h (4.00-62.00). The median duration of the ICU hospitalization was 48.00 h (24.00-120.00). At least one ISO-related side effect was recorded in 23 out of 26 (88.5%) episodes. Conclusion: To the authors' knowledge, this is the first clinical study that addresses the administration of ISO for RSE/SRSE treatment in dogs. The use of ISO may be beneficial in terminating RSE/SRSE; however, further prospective studies are necessary to confirm this observation.

Orally administered gabapentin and alprazolam induce comparable levels of anxiolysis and sedation in cats.

OBJECTIVE: To assess the level of anxiolysis achieved by alprazolam and gabapentin in hospitalized cats prior to elective ovariohysterectomy and to evaluate the sedative effects of these agents. ANIMALS: 60 client-owned female cats classified as American Society of Anesthesiologists physical status 1, admitted for elective ovariohysterectomy at a veterinary teaching hospital. METHODS: The cats were prospectively and randomly allocated into 3 groups. Ninety minutes before evaluation, group G received gabapentin (100 mg/cat), group A received alprazolam (0.125 mg/cat), and group P received no medication (placebo). Stress, enclosure activity, and sedation scores were blindly evaluated. RESULTS: Stress scores were similar in cats treated with gabapentin and alprazolam and gabapentin-treated cats had significantly lower stress score than those of the placebo group. Enclosure activity levels did not differ among the groups. Additionally, gabapentin and alprazolam resulted in similar sedation levels 90 minutes after treatment, which differed significantly compared to placebo. CLINICAL RELEVANCE: The results of this study suggest that gabapentin provides similar anxiolysis in cats to that of alprazolam when evaluated 90 minutes after administration. Although no difference was noted in sedation levels between gabapentin and alprazolam, both induced deeper sedation than placebo.

A Retrospective Study on Canine and Feline Mortality during Anaesthesia at a University Clinic in Greece.

This retrospective cohort study investigated the mortality rate during anaesthesia and possible contributing factors in canine and feline population in an academic institution in Greece. Data on 1187 dogs and 250 cats which underwent general anaesthesia from 1 January 2018 to 31 December 2019 at the Veterinary Faculty of the Aristotle University of Thessaloniki were analysed regarding cardiac arrest and mortality. In dogs, the rate of cardiac arrest was 1.1% and the rate of death was 0.6%. In cats, these rates were 2.8% and 0.8%, respectively. The mortality rate in healthy/mild disease (ASA I-II) dogs was 0.1% and in cats was 0.5%. Sick (ASA III-V) dogs exhibited a death rate of 2.6%, while sick cats had a rate of 2.2%. In dogs, ASA status had a positive association with cardiac arrest and mortality, with sick dogs being 23 times more likely to suffer cardiac arrest and 24.5 times more likely to die than healthy/mild disease ones. Other factors associated with cardiac arrest and mortality were the anaesthetic protocol and the use of inotropes. In cats, premedication and inotropic support were related to cardiac arrest and death. Feline anaesthesia involves higher risk, and requires greater vigilance in peri-anaesthetic management than dogs.

Contribution to the Study of Perioperative Factors Affecting the Restoration of Dog's Mobility after Femoral Head and Neck Excision: A Clinical Study in 30 Dogs.

This study aimed to compare postoperative analgesia and the time of limb weight bearing induced by the intraoperative administration of a local anesthetic at the site of the femoral head and neck excision (FHNE) in dogs, with and without the administration of preoperative epidural anesthesia. Additionally, the impact of postoperative opioid drug administration on weight-bearing time was examined. This randomized, blinded, prospective clinical study included 30 client-owned dogs. The dogs were randomly divided into three groups (A, B, C), each further divided into two subgroups (A1, A2, B1, B2, C1, C2). Group A received epidural anesthesia and ropivacaine at the ostectomy site, Group B received only ropivacaine, and Group C served as the control group. Subgroup 1 received a non-steroidal anti-inflammatory drug postoperatively, while Subgroup 2 had tramadol added to their regimen. Pain assessment was conducted using the University of Melbourne Pain Scale (UMPS) and an algometer. The study concluded that multimodal analgesia, utilizing all the aforementioned analgesic techniques, resulted in faster limb weight bearing for dogs undergoing FHNE.

Evaluation of Survival of Subdermal Plexus Skin Flaps in 8 Cats After Injection of Platelet Rich Plasma.

The aim of the present study was to evaluate the effect of platelet-rich plasma injection on the survival of experimentally developed subdermal plexus skin flaps in cats. Two flaps, 2 cm wide and 6 cm long were created bilaterally in the dorsal midline in 8 cats. Each flap was randomized to 1 of 2 groups: platelet-rich plasma injection and control. After flap development, the flaps were immediately placed back on the recipient bed. Then 1.8 mL of platelet-rich plasma was equally injected into 6 different parts of the treatment flap. All flaps were evaluated macroscopically daily and on days 0, 7, 14, and 25 by planimetry, Laser Doppler flowmetry, and histology. Mean flap survival on day 14 was 80.437 % (±22.745) for the treatment group and 66.516 % (±24,12) for the control group with no statistically significant difference between the 2 groups (P = .158). Histologically, a significant difference was found between the base of the PRP and the control flap in edema score on day 25 (P = .034). In conclusion, there is no evidence to support the use of platelet-rich plasma in subdermal plexus flaps in cats. However, the use of platelet-rich plasma may aid in reducing edema of subdermal plexus flaps.

Prophylactic Effect of Fenestration on the Recurrence of Thoracolumbar Intervertebral Disc Disease in Dogs.

This systematic review aimed to assess the effect of prophylactic fenestration (PF) on the recurrence of thoracolumbar (TL) intervertebral disc (IVD) disease in dogs. Three online databases were searched (Web of Science, MEDLINE via PubMed, SCOPUS), 115 relevant studies were thoroughly examined by the authors, 29 of which met the pre-defined inclusion criteria for this systematic review. Data about the initial treatment, the performance of PF, the incidence of recurrence, and the site of recurrence were extracted. Most of the studies were deemed to have serious to moderate risk of bias. Out of 5457 dogs, 1264 underwent prophylactic fenestration. A total of 504 cases of suspected or confirmed recurrence were recorded, in which 164 (32.54% of total recurrences and 11.02% of PF cases) were in dogs treated with PF. In order to perform quantitative analysis for the recurrence odds, we conducted a meta-analysis. Five studies were included that met the inclusion criteria. Despite a large number of relevant publications, the quality of the evidence they provide is low. This prevented us from reaching a definitive conclusion on the prophylactic effect of fenestration on recurrence in dogs surgically treated for TL IVDH.

The Effect of Premedication on the Incidence of Gastroesophageal Reflux in 270 Dogs Undergoing General Anesthesia.

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.

Locally Injected Autologous Platelet-Rich Plasma Improves Cutaneous Wound Healing in Cats.

Cutaneous defects in cats are commonly encountered in clinical practice, and healing can be accomplished by first or second intention. Platelet-rich plasma (PRP) is characterized by a plasma concentration containing a large number of platelets in a small volume of plasma. The objective of the present study was to record the efficacy of PRP infiltration in open wounds in laboratory cats. Six wounds were created in the dorsal midline of eight laboratory cats, with the wounds of one side designated as the PRP group and the wounds of the other side as the control group. Wound healing was evaluated by daily clinical examination, planimetry, laser Doppler flowmetry, and histologic examination on days 0, 7, 14, and 25, and by measurement of metalloproteinases (MMPs)-2 and -9 and tissue inhibitor metalloproteinase (TIMP)-1 on days 0, 14, and 25. Based on the results of the present study, the mean time for full coverage with granulation tissue was shorter in the PRP group, the mean contraction and total wound healing percentage were increased compared to the control group, and finally, the perfusion measured with laser Doppler flowmetry was higher in the PRP group during all examination days. In conclusion, this is the first study focusing on the topical application of PRP in the treatment of open wounds in laboratory cats, and our results are encouraging-showing a more rapid healing in the PRP group.

The role of the sequential organ failure assessment score in evaluating the outcome in dogs with parvoviral enteritis.

SCIENTIFIC BACKGROUND: The aim of this prospective study was to assess whether the Sequential Organ Failure Assessment (SOFA) score could be indicative of outcome (survival to discharge) in dogs with parvoviral enteritis. METHODS: In 35 naturally infected dogs, the SOFA score and clinical score were calculated and the presence of systemic inflammatory response syndrome was verified on admission and during the first four days of hospitalization. RESULTS: 26 dogs survived, and out of the 9 non-survivors, 6 dogs had positive blood cultures. Mean SOFA scores and clinical scores between survivors and non-survivors and between septic and non-septic dogs on admission and on each hospitalization day were significantly different. Trends in SOFA score indicated that in non-survivors and septic dogs there was an increase in SOFA score during the first four days of hospitalization and a decrease occurred in survivors and non-septic dogs. The area under the curve (ROC curve analysis) for SOFA score predicting the outcome was 0.797 and predicting sepsis was 0.834. The best cut-off point of SOFA score for predicting the final outcome was 3.5 and the best cut-off of SOFA score for predicting sepsis was also 3.5. CONCLUSIONS: Either single values or trends in SOFA score can assist in suspecting sepsis and reaching prognosis in parvoviral enteritis.

Factors Affecting Intraoperative Gastro-Oesophageal Reflux in Dogs and Cats.

In animals, gastro-oesophageal reflux (GOR) may occur during anaesthesia, and it can lead to severe consequences such as oesophagitis and oesophageal stricture. This systematic review investigates the effect of fasting duration and anaesthetic and nonanaesthetic drugs on GOR in dogs and cats during general anaesthesia. Fifteen clinical studies met the inclusion criteria in this systematic review. In thirteen studies the population was dogs, while in two studies the population was cats. In the meta-analysis, seven studies were included. Four studies on the effect of fasting duration on GOR in dogs were included in the meta-analysis. In total, 191 dogs had a fasting duration less than 5 h, while 311 dogs had a fasting duration more than 5 h. The heterogeneity of the studies was high and statistically significant (p = 0.0002, I2 = 85%), but the overall effect was statistically nonsignificant (p = 0.82, odds ratio = 0.81, 95% CI 0.15, 4.26), in favour of the low fasting duration (<5 h). Concerning the effect of antacids on GOR, three studies were included in the meta-analysis. The heterogeneity of the studies was low and nonsignificant (p = 0.13, I2 = 52%) and the overall effect was statistically nonsignificant (p = 0.24). The low number of studies and the diverse factors affecting the incidence of reflux prevented us from reaching valuable conclusions on the risk factors for GOR.

Limited cross-species transmission and absence of mutations associated with SARS-CoV-2 adaptation in cats: A case study of infection in a small household setting.

In the present study, the course of SARS-CoV-2 natural infection in two asymptomatic cats, which were negative for immunosuppressive retroviral infections, is investigated. The source of the virus for the cats was their COVID-19-affected owner, with whom they were in continuous proximity in a small household setting. The owner's signs included fatigue, sneezing, anosmia and loss of taste, and diagnosis was confirmed 4 days after symptom onset. Oropharyngeal and faecal swabs were collected from the cats, to investigate the course of SARS-CoV-2 RNA concentrations, as well as the directionality of the chain of virus transmission. Both infected cats were real-time RT-PCR-positive on various time-points. Pharyngeal shedding of at least 6 days was observed in them, with high SARS-CoV-2 titres (> 7 Log10 copies/swab) on the first sampling time-point, that is, 7 days after the onset of owner's clinical signs. In one cat, after the initial decline, slightly increasing virus titres were measured 3 to 6 days after the first real-time RT-PCR-positive swab. Serological testing of this cat revealed absence of seroconversion. The course of viral RNA concentrations in the faecal swabs of the other cat was similar to that in its pharynx. The detected SARS-CoV-2 strains, from both infected cats and their owner, underwent whole-genome sequencing, revealing the absence of emergence of cross-species adaptive mutations in cats. The results support the notion that human SARS-CoV-2 strains are relatively well-adapted to cats. It is still unclear whether asymptomatic animals could play a role in COVID-19 epidemiology, in case of interaction with naïve animals and/or people. Our findings highlight difficulties in SARS-CoV-2 transmission to cats, as neither the two infected cats nor their owner was able to transmit the virus to a third cat living in the same small flat, despite their very close contact during the days corresponding to high virus shedding.

Use of propofol to induce food consumption by anorectic dogs following ovariohysterectomy.

OBJECTIVE: To determine whether IV propofol administration at a dose of 2 mg/kg (0.9 mg/lb) could induce food consumption by anorectic female dogs following elective ovariohysterectomy. ANIMALS: 51 healthy female dogs that failed to eat voluntarily when food was offered 6 hours after ovariohysterectomy. PROCEDURES: In a randomized, blinded, controlled clinical trial, dogs received propofol (2 mg/kg; n = 31) or an equivalent volume of saline (0.9% NaCl) solution (20) IV 6 hours after ovariohysterectomy. Afterward, food was offered to the dogs and food consumption was reassessed. Pain, sedation, and stress were scored before and immediately after treatment. RESULTS: 27 of the 31 (87%) dogs in the propofol group consumed food immediately after administration of the assigned treatment, whereas only 1 of 20 (5%) dogs in the placebo group did. No difference in pain, sedation, or stress scores was identified between the 2 groups. Sedation scores for dogs in the propofol group increased immediately after propofol administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that food consumption following elective surgical procedures can be effectively induced in anorectic female dogs by IV administration of propofol at a dose of 2 mg/kg.

The Role of Magnesium in the Management of Acute and Long-Term Symptoms Caused by Tetanus in Two Dogs.

Tetanus in dogs is a relatively uncommon neurological disease caused by the sporogenic bacillus Clostridium tetani. This disease is associated with prolonged hospitalization and mortality rates from 8%-50%. A 2-year-old, neutered male King Charles Spaniel and an approximately 8-months-old female Mongrel dog presented to Companion Animal Clinic with symptoms of muscle rigidity and generalized stiffness. A tentative diagnosis of generalized tetanus was made in both dogs. Treatment consisted of IV fluids, antibiotics (metronidazole), human tetanus antitoxin, analgesics and supportive care. Muscle relaxation was provided by midazolam. Acetylpromazine meleate was added to the treatment of the second dog to better control excitability. Each dog received magnesium therapy on the 10th and 3rd days, respectively; which was provided per os to the first dog and constant rate infusion (4 mg/kg/h) to the second dog. The addition of magnesium helped to increase muscle relaxation and increased the time interval between acetylpromazine administration. On the tenth day, magnesium sulfate was discontinued from the second dog and magnesium aspartate (12 mg/kg), twice a day, per os was administered in both animals. Further muscle relaxation was noted in both dogs with a substantial reduction of tetanus symptoms. Both dogs were discharged from Intensive Care Unit on the 14th and 13th day respectively with sole treatment of magnesium aspartate (12 mg/kg) orally, twice a day. Magnesium aspartate was continued for 14 days and 12 days respectively. Both dogs had progressive reduction of muscle rigidity and the first dog recovered completely. The second dog presented again with muscle rigidity and increased spinal reflexes after the discontinuation of magnesium aspartate, thus therapy with magnesium aspartate was started again and symptoms subsided after the second oral dose of magnesium. Therapy was continued for two more weeks during which muscle rigidity subsided and then was stopped. At that time, tetanus symptoms did not relapse and the dog was considered fully recovered. According to the findings of this case series, magnesium therapy may provide further muscle relaxation during the standard therapeutic protocol of tetanus in dogs. In addition, long term symptoms of the disease were adequately managed with the administration of magnesium aspartate, orally.

The Effect of the Preoperative Fasting Regimen on the Incidence of Gastro-Oesophageal Reflux in 90 Dogs.

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.

Presumptive Lornoxicam Intoxication in Four Dogs.

Lornoxicam is a nonsteroidal anti-inflammatory drug extensively used in human medicine, which is not approved for canine use. Lornoxicam intoxication has been rarely reported in dogs. Four dogs of various breeds, aged 7 months to 10 years, were admitted with a recent history of melena, anorexia and depression, occurring 1-4 days after the ingestion of lornoxicam (dose range: 0.53-2.7 [median 1.17] mg/kg). No clinically relevant comorbidities were documented, but low doses of prednisolone had been given in 3 of the dogs, in close temporal association with lornoxicam. Major clinical and clinicopathologic findings on admission included mucosal pallor, melena, depression, severe anemia, neutrophilic leucocytosis, and panhypoproteinemia. Perforated pyloric and duodenal ulcers were documented in 3 dogs by exploratory celiotomy or postmortem. Prolonged hospitalization (5-20 days) with extensive supportive care and multiple blood transfusions was required in 3 of the 4 dogs who survived to discharge. Lornoxicam ingestion may cause protracted and severe gastrointestinal tract injury and bleeding, blood loss anemia, panhypoproteinemia, and perforated gastrointestinal ulcers, associated with significant morbidity and mortality in dogs.

Bilothorax Associated with Bile Peritonitis in a Dog with No Diaphragmatic Disruption: A Case Report.

A 4-year-old intact male mixed-breed dog was presented with vomiting and severe depression of 6-day duration after being struck by a car 2 weeks before presentation. Clinical examination revealed hypothermia, respiratory difficulty, jaundice, and a bicavitary (pleural and peritoneal) effusion. Hematological and biochemical abnormalities included neutrophilic leukocytosis, increased total bilirubin concentration, and increased serum lipase activity. Biochemical and cytological evaluation of both abdominal and thoracic fluids were suggestive of bilious effusions. During celiotomy, a rupture of the cystic duct was observed, which necessitated cholecystectomy. A diaphragmatic rupture was not found. A thoracostomy tube was inserted in the right pleural space, and continuous suction was maintained for 48 hours. The dog was discharged 20 days after surgery and no abnormalities were detected on either blood tests or ultrasonographic examinations of the thorax and abdomen on follow-up examination 7 months after surgery. The presence of a bilothorax should be considered in animals with bile peritonitis, grossly intact diaphragm and pleural effusion. The exact mechanisms of the development of bilothorax are unclear, but the transport of bile through microscopic congenital or acquired weaknesses or defects of the diaphragm, via abdominal lymphatics penetrating the diaphragm and draining into the thoracic lymphatics represent the most probable route.

Circulatory effects of dexmedetomidine in early sepsis: a randomised controlled experimental study.

We designed this experimental study with a view to evaluate the effects of dexmedetomidine (DEX) on cardiac performance and systemic and peripheral hemodynamics in healthy and early-stage endotoxemia swine models. Our study hypothesis was that DEX can ensure hemodynamic stability during the course of endotoxemia. Thirty-two male pigs (25-27 kg) were assigned into four groups: (1) no intervention (group A), (2) DEX 0.8 µg/kg was administered in non-septic animals (group B), (3) sepsis induced by intravenous Escherichia coli endotoxin (group C) and (4) DEX 0.8 µg/kg was administered in septic animals (group D). Hemodynamic parameters such as heart rate, mean blood pressure, central venous pressure, pulmonary artery pressures, pulmonary artery occlusion pressure, pulmonary vascular resistance and cardiac output were continuously recorded. Central venous oxygen saturation was also measured in order to obtain a complete evaluation of cardiovascular response to sepsis. Heart rate was decreased, whilst mean arterial pressure decrease was alleviated after DEX administration in septic animals. In addition, central venous pressure was stable in animals with sepsis after DEX infusion. Sepsis dramatically elevated pulmonary function indicators but DEX succeeded in ameliorating this effect. The important decrease measured in central venous oxygen saturation in both sepsis groups reflected the decreased perfusion of tissues that takes place at the end of early sepsis. Our findings support the hypothesis that DEX has beneficial effects on heart rate and pulmonary artery pressure, whilst reduction in systemic blood pressure occurs at acceptable levels.

Hereditary methemoglobinemia in a cyanotic cat presented for ovariohysterectomy.

A 1-year-old, female, domestic shorthair cat with a history of cyanotic mucous membranes for several months was referred for ovariohysterectomy. Blood samples exhibited a noticeably brownish discoloration, while laboratory screening revealed mild-to-moderate erythrocytosis and near normal partial arterial oxygen pressure. Blood methemoglobin content was 41% of total hemoglobin concentration, and erythrocytic methemoglobin reductase activity was < 1% compared with control samples. A diagnosis of hereditary methemoglobinemia was established. After an intravenous injection of methylene blue, the cat's mucous membranes became transiently pink, and the ovariohysterectomy was uneventful. Methylene blue may have improved safety during anesthesia and surgery. Hereditary methemoglobinemia should be considered in persistently cyanotic cats with normal partial arterial oxygen pressure and lack of evidence of cardiopulmonary disease, anemia, or toxin exposure.

Méthémoglobinémie héréditaire chez une chatte cyanotique présentée pour une ovariohystérectomie. Une chatte domestique âgée de 1 an avec une anamnèse de muqueuses cyanotiques pendant plusieurs mois a été recommandée pour l'ovariohystérectomie. Des prélèvements sanguins présentaient une décoloration brune manifeste tandis que les tests de laboratoire ont révélé une érythrocytose de légère à modérée et une pression d'oxygène artérielle partielle presque normale. Le contenu de méthémoglobine sanguine était de 41 % de la concentration totale des hémoglobines et l'activité de la réductase de la méthémoglobine érythrocytaire était < 1 % comparativement aux prélèvements témoins. Un diagnostic de méthémoglobinémie héréditaire a été posé. Après une injection intraveineuse de bleu de méthylène, les muqueuses du chat sont devenues provisoirement roses et l'ovariohystérectomie a été réalisée sans complications. Le bleu de méthylène peut avoir amélioré l'innocuité durant l'anesthésie et la chirurgie.(Traduit par Isabelle Vallières).