Ostéosarcome, Cannabis, Dexmédétomidine, Lévobupivacaïne ...



1/ Pain characterization and response to palliative care in dogs with naturally-occurring appendicular osteosarcoma: An open label clinical trial

Monteiro BP, de Lorimier L-P, Moreau M, Beauchamp G, Blair J, Lussier B, et al. (2018) 

PLoS ONE 13(12): e0207200.

Résumé : 

This study aimed to characterize bone cancer pain (quantitative sensory testing (QST), stance asymmetry index, actimetry, scores of pain and quality of life (QoL)) in dogs with appendicular osteosarcoma (OSA), and to evaluate a stepwise palliative analgesic treatment. The pain profile of thirteen client-owned dogs with OSA was compared with seven healthy dogs.

Dogs with OSA were then enrolled in a prospective, open-label, clinical trial.
Outcome measures included: primary and secondary mechanical thresholds (MT), conditioned pain modulation (CPM), stance asymmetry index, actimetry (most and least active periods), visual analog scales and QoL.

After baseline assessments, stepwise treatment comprised orally administered cimicoxib (2 mg/kg q 24h), amitriptyline (1–1.5 mg/kg q 24h) and gabapentin (10 mg/kg q 8h); re-evaluations were performed after 14 (D14), 21 (D21) and 28 (D28) days, respectively.

Statistics used mixed linear models (α = 5%; one-sided).
Centralized nociceptive sensitivity (primary and secondary MT, and dynamic allodynia) was recorded in OSA dogs. Healthy dogs had responsive CPM, but CPM was deficient in OSA dogs.
Construct validity was observed for the QST protocol. Asymmetry index was significantly present in OSA dogs.

The CPM improved significantly at D14. When compared with baseline (log mean ± SD: 4.1 ± 0.04), most active actimetry significantly improved at D14 (4.3 ± 0.04), D21 and D28 (4.2 ± 0.04 for both).
When compared with baseline, least active actimetry significantly decreased after treatment at all time-points indicating improvement in night-time restlessness.
No other significant treatment effect was observed. Except for tactile threshold and actimetry, all outcomes worsened when gabapentin was added to cimicoxib-amitriptyline.
Dogs with bone cancer are affected by widespread somatosensory sensitivity characterized by peripheral and central sensitization and have a deficient inhibitory system.

This severe pain is mostly refractory to palliative analgesic treatment, and the latter was only detected by specific and sensitive outcomes.

PDF à https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0207200&type=printable

2/ Evaluation of the cardiorespiratory effects of the alpha-2 adrenoceptor agonists xylazine, medetomidine and dexmedetomidine in combination with ketamine in dogs

Guzel O., Kaya D.A., Altunatmaz K., Sevim G., Sezer D., Erdikmen D.O. (2018)

Veterinarni Medicina, 63: 546-554.

Résumé : 

In this study, we compared the effects of xylazine, medetomidine and dexmedetomidine in combination with ketamine on heart rate, respiratory rate, blood gas values, temperature and sedation scores.

A total of 30 dogs were evaluated. The dogs were randomly allocated into three anaesthesia groups, each of which included ten dogs.

  • The first group, denoted the xylazine/ketamine group, intravenously received xylazine (0.5 mg/kg) for premedication and ketamine (5 mg/kg) for induction.

  • The second group, the medetomidine/ketamine group, intravenously received medetomidine (10 µg/kg) followed by ketamine (5 mg/kg).

  • The third group received the dexmedetomidine/ketamine combination. This group intravenously received dexmedetomidine (3 µg/kg) for premedication and ketamine (5 mg/kg).

Heart rate, respiratory rate, oxygen saturation, blood gas parameters and temperature were recorded for all patients immediately before sedation onset (T0), five minutes after sedation onset (T1) and five minutes after endotracheal intubation following ketamine injection (T2).

The end tidal carbon dioxide level was recorded at T2. A significant decrease in heart rate occurred following premedication in all groups.

However, the decrease was most marked in the medetomidine/ketamine group.

An increase was observed in venous partial pressure of carbon dioxide values at T2 in the xylazine/ketamine group compared to the medetomidine/ketamine and dexmedetomidine/ketamine groups.

The end tidal carbon dioxide levels were higher in the medetomidine/ketamine group than in the other two groups, and oxygen saturation of haemoglobin levels in the same group were found to be lower than in the others. It was determined that none of α2-agonists, namely xylazine, medetomidine or dexmedetomidine, had superior properties over the others.

If medetomidine is used, special care should be taken because of the rapid decrease in heart rate.

PDF à https://www.agriculturejournals.cz/publicFiles/92_2018-VETMED.pdf

3/ US veterinarians’ knowledge, experience and perception regarding the use of cannabidiol for canine medical conditions

Lori R. Kogan, Regina Schoenfeld-Tacher, Peter W. Hellyer and Mark Rishniw

Front. Vet. Sci., 17 Dec. 2018

Résumé : 

Due to the myriad of laws concerning cannabis, there is little empirical research regarding the veterinary use of cannabidiol (CBD). This study gauged US veterinarians’ knowledge level, views and experiences related to the use of cannabinoids in the medical treatment of dogs. Participants (n = 2130) completed an anonymous, online survey.

Results were analyzed based on legal status of recreational marijuana in the participants’ state of practice, and year of graduation from veterinary school. Participants felt comfortable in their knowledge of the differences between THC and marijuana, as well as the toxic effects of marijuana in dogs.

Most veterinarians (61.5%) felt comfortable discussing the use of CBD with their colleagues, but only 45.5% felt comfortable discussing this topic with clients.

No differences were found based on state of practice, but recent graduates were less comfortable discussing the topic. Veterinarians and clients in states with legalized recreational marijuana were more likely to talk about the use of CBD products to treat canine ailments than those in other states. Overall, CBD was most frequently discussed as a potential treatment for pain management, anxiety and seizures.

Veterinarians practicing in states with legalized recreational marijuana were more likely to advise their clients and recommend the use of CBD, while there was no difference in the likelihood of prescribing CBD products.

Recent veterinary graduates were less likely to recommend or prescribe CBD. The most commonly used CBD formulations were oil/extract and edibles. These were most helpful in providing analgesia for chronic and acute pain, relieving anxiety and decreasing seizure frequency/severity. The most commonly reported side-effect was sedation. Participants felt their state veterinary associations and veterinary boards did not provide sufficient guidance for them to practice within applicable laws.

Recent graduates and those practicing in states with legalized recreational marijuana were more likely to agree that research regarding the use of CBD in dogs is needed. These same groups also felt that marijuana and CBD should not remain classified as Schedule I drugs. Most participants agreed that both marijuana and CBD products offer benefits for humans and expressed support for use of CBD products for animals.

4/ Pharmacokinetics of Bedrocan®, a cannabis oil extract, in fasting and fed dogs: An explorative study

Beata Łebkowska-Wieruszewska, Fabio Stefanelli, Silvio Chericoni, Helen Owen, Mario Giorgi

Res. Vet. Sci., In Press, Accepted Manuscript, Available online 17 December 2018

Résumé : 

The aim of this study was to explore the pharmacokinetics of the two main active compounds (THC and CBD) contained in the cannabis oil extract Bedrocan® in fasting and fed dogs. Bedrocan® (20% delta-9-tetrahydrocannabinol [THC] and 0.5% cannabidiol [CBD]) was administered at 1.5 and 0.037 mg/kg THC and CBD, respectively in fasted and fed dogs according to a 2 × 2 cross over study design. The quantification of the two active ingredients was performed by LC/MS.

No detectable concentrations of CDB were found at any collection time. THC was quantifiable from 0.5 to 10 h, although there was large inter-subject variability. Fed dogs showed a longer absorption phase (Tmax 5 vs 1.25 h) and lower maximal blood concentration (7.1 vs 24 ng/mL) compared with the fasted group. A larger AUC was found in the fasted group; the relative oral bioavailability in fed animals was 48.22%.

5/ Effect of Levobupivacaine administred intraperitoneally on fisiological variables and on intra and post surgery pain, in dogs undergoing ovariohysterectomy

G.L. Costa, B. Nastasi, F. Spadola, F. Leonardi, C. Interlandi

J. Vet. Behav., In Press, Accepted Manuscript, Available online 8 December 2018



The aim of this study is to evaluate intra- and post-operative efficacy and cardiovascular effects of levobupivacaine compared with bupivacaine, administered intraperitoneally in dogs undergoing ovariohysterectomy surgery. 


Thirty females, divided into three groups of ten subjects B, L and E. All subjects received dexmedetomidine 5 μg Kg-1 and methadone 0,3 mg Kg-1 intramuscularly, propofol 4 mg Kg-1 intravenously and isoflurane after intubation. After laparotomy, bupivacaine 2,5 mg Kg-1 (B group), levobupivacaine 2,5 mg Kg-1 (L group) or saline solution 0,9% (E group) were sprayed on ovarian stalks and on the neck of the uterus. Heart rate (HR), respiratory rate (RR), hemoglobin saturation (Sp02), non-invasive systolic blood pressure (SAP), carbon dioxide at the end of expiration (ETCO2) and concentration of inspired isofluorane (CI) were recorded . Evaluation of intra-operative analgesia was performed with a cumulative pain scale, while evaluation of post-operative analgesia was performed using the University of Melbourne Pain Scale (UMPS).


Intraoperative analgesia was significantly different among the groups p=0.000, L group scores were lower than groups B and E. 

Total pain score, during the 24 hours after extubation, was significantly different between the groups. In fact, in Groups B and L scores were statistically lower than Group E. In our study there were no differences in anesthetic power between the two local anesthetics. 

No patients manifested side effects. Clinical Significance: Intraperitoneal anesthesia, with levobupivacaine represents an effective and safe method to control intra and postoperative pain in abdominal surgery.