Considering the widespread use of rabbits in research that potentially causes pain and discomfort and the limited number of pain assessment validated tools in this species, we aimed to develop and validate a scale of acute postoperative pain in rabbits (RPBS). Footage of 58 rabbits from previous studies were used, recorded at ‘baseline’ (before orthopaedic and soft tissue surgeries), ‘pain’ (after surgery), ‘analgesia’ (after analgesic), and ‘24h post’ (24 hours after surgery). The videos were randomised and assessed twice by four evaluators, within one-month interval between evaluations. After content validation, RBPS was further refined using the criteria from the validation. According to the principal component analysis, RPBS was considered unidimensional. The intra- and inter-observer reliability was excellent (ICC>0.80) for all evaluators. There was a high Spearman’s correlation of the RPBS with unidimensional scales (>0.80) and a moderate correlation with the Rabbit Grimace Scale (0.68), confirming criterion validity. According to the mixed linear model, the scale was responsive, shown by the increase in pain scores after surgery. Construct validity was confirmed by known-group approach and internal relationships among items. Adequate item-total correlation (>0.3) was observed for all items, except for the attention to the affected area (0.04). The internal consistency was very good (Cronbach’s α coefficient = 0.78; Mcdonald’s ω coefficient = 0.83). The cut-off score for rescue analgesia was ≥3, with an area under the curve >0.95, demonstrating a high discriminatory capacity of the instrument. Scores 3 and 4 were within the uncertainty diagnostic zone. Specificity was 87% and sensitivity was 90%. It was concluded that the RPBS presented content, criterion, and construct validities, responsiveness, and reliability to assess acute pain in rabbits submitted to orthopaedic and soft tissue surgeries. The cut-off for rescue analgesia serves as a basis for the administration of analgesics to rabbits submitted to painful procedures.

Rabbits are widely used in studies focusing on pain. However, pain is undertreated in this species and one possible factor to explain this is the lack of evaluation methods. The objective of this study was to identify behaviours related to orthopaedic pain in rabbits and to evaluate the influence of the presence of an observer on these behaviours. Twenty-eight rabbits undergoing orthopaedic surgery and filmed 24 hours before surgery, and 1 hour (before rescue analgesia), 4 hours (3 hours after rescue analgesia), and 24 hours post-recovery were observed in the presence and absence of an observer. The frequency and/or duration of behaviours were compared over time and between the presence and absence of the observer using the Friedman and Wilcoxon tests respectively. Data are expressed as median and interquartile range and a significant difference was considered when p<0.05. At 1 hour post-recovery, the rabbits showed reduced activity, hopping, change posture, position in the cage, explore, and open eyes in both the presence and absence of the observer. In the absence of the observer, quadrupedal posture, interact with pinecone, and eat carrot also decreased, while wince behaviour increased. In the presence of the observer, before surgery, the rabbits were less active (Presence-280; 162–300, Absence-300; 300–300) and presented a lower duration of explore (Presence-3; 0–32, Absence-40; 4–63). Post-recovery the rabbits flinched less (Presence-0; 0–0, Absence-0; 0–1) and suspended the affected limb less (Presence-0; 0–0, Absence-0; 0–65). After rescue analgesia the rabbits put weight on and raised the affected limb less (Presence-0; 0–0, Absence-0; 0–2) and licked the affected area less (Presence-0; 0–0, Absence-0; 0–2). These findings demonstrate that the presence of the observer inhibited pain-free behaviours in the rabbits, leading to a false impression of pain, and after the surgery the rabbits masked some pain signs related to the affected area.

As alterações dos anéis vasculares são decorrentes de malformações dos grandes vasos e seus ramos, sendo que a persistência do quarto arco aórtico direito é a mais comum em cães. Este trabalho relata o caso de um canino, fêmea, de três meses, com quadro clínico de regurgitação. A radiografia lateral contrastada mostrou constrição esofágica próxima à base cardíaca e sua consequente dilatação cranial. O tratamento instituído foi a correção cirúrgica, por meio da transecção do ligamento arterioso para a liberação do esôfago, bem como o manejo nutricional adequado. O prognóstico é reservado, podendo haver remissão do megaesôfago e melhora do quadro de regurgitações, conferindo ao paciente, melhor qualidade de vida.

Background: Malignant peripheral nerve sheath tumors are neurogenic neoplasms that originate from cells that surround the axons of peripheral nerves. Surgery is the treatment of choice for peripheral nerve sheath tumors. They have a better prognosis when the lesion is in the extremity of a limb and the surgeon leaves wide peripheral margins after resection. However, this procedure makes local treatment a challenge due to difficult wound healing in this region. This report describes a successful case involving the use of a meshed skin graft immediately after resection of a neurofibrosarcoma in the distal region of the radius bone of a dog.Case: A 6-year-old Boxer bitch weighing 40 kg was admitted with a history of a round, firm, non-ulcerated skin nodule attached to the lateral side of the distal region of the right radius bone, which had been present for about 40 days. Fine needle aspiration cytology of the lesion showed the presence of mesenchymal cells, suggesting a sarcoma. Thus, the decision was made for an incisional biopsy to confirm the diagnosis and for the preparation of a subdermal pattern tubular flap for subsequent rotation and transposition to close the wound that would be formed after the complete removal of the lesion. After the 7th postoperative day, the diagnosis of low-grade neurofibrosarcoma was confirmed and due to the presence of necrotic onset in the middle portion of the tubular flap, further surgical intervention was scheduled for the resection of the tube flap, en bloc removal of the neoplastic lesion with peripheral margins of 2 cm, and wound closure with a free skin graft. A mesh skin graft was made with a portion of the right flank skin. The mesh graft was carefully implanted on the recipient bed using simple interrupted sutures with a 3-0 non-absorbable monofilament suture material. A dressing made with water-based sterile lubricating solution and gauze and a modified Robert Jones bandage were applied. The patient was treated with analgesic medication, antimicrobial therapy, and gastric protectors. The first bandage and dressing were changed after 48 h, and only warm physiological solution was used. Histopathological analysis confirmed the diagnosis of low-grade neurofibrosarcoma with free surgical margins. The dressing was changed every 72 h for up to 12 postoperative days, when the immobilization was removed, and wound cleaning could be completed at home using physiological solution and a dressing with nitrofurazone ointment. Granulation tissue was first seen at day 12, and at day 30 the wound was completely closed.Discussion: The primary closure of skin defects after the resection of tumors located in the distal portion of limbs is often not possible due to a lack of adjacent skin. Thus, grafts are commonly used to repair the skin in these areas using the technique presented in this report. In order to survive, skin grafts need a vascular bed capable of allowing new blood vessel connections with the implanted skin portion. There is no consensus in the literature on the best bed for graft implantations. In the case described in this study, a free mesh graft was implanted on a fresh wound without granulation tissue, which resulted in excellent clinical evolution and total survival of the graft. Excellent clinical results were achieved with the graft, since its survival and adherence to the recipient bed occurred without complications. The clinical result of this case suggests that the application of full-thickness mesh grafts to fresh wounds in distal limbs immediately after tumor resection is a good alternative when the surgical wound is too large (which prevents primary closure). Good preoperative planning associated with good surgical techniques and adequate postoperative management are essential for the success of the technique under these conditions.

Background: Mastectomy, a procedure with high pain stimulation, is the treatment of choice for bitches with breast cancer. Tumescent anaesthesia is widely used for transoperative and postoperative analgesia in bitches submitted to mastectomy, because facilitates tissue divulsion, also contributing significantly for the rapid recovery of patients. Although, there is no consensus as to which local anesthetic to use and at what concentration it should be used. Herein was investigated which local anesthetics, lidocaine or ropivacaine, when used in tumescent solutions, could provide a more lasting analgesic effect in the postoperative period in bitches submitted to radical unilateral mastectomy.Materials, Methods & Results: Sixteen bitches were sedated with chlorpromazine (0.3 mg/kg) and meperidine (3 mg/kg) followed by anesthesia with propofol and isofluorane. Then, bitches were randomly assigned to two groups (n= 8 each): LG group, infused with 15 mL/kg of tumescence solution containing 0.1% lidocaine; and RG group, infused with 15 mL/kg of tumescence solution with 0.1% ropivacaine. The study was conducted in a double-blind fashion. Control group did not include, because the patients would be submitted to severe or unbearable pain, according to the short-form of the Glasgow pain Scale (CMPS-SF). The heart (HR) and respiratory (ƒ) rates, and systolic blood pressure (SBP) were measured in the pre-operative period and immediately after extubation (Mextub) and at 0.5 h, 1 h, 2 h, 4 h, 8 h, and 12 h after the extubation. Analgesic efficacy was assessed using the CMPS-SF and von Frey filaments. Both groups showed higher means for HR at 0.5 h (167 ± 7 in LG; 170 ± 7 in RG) than at 4 h (117 ± 7 in LG; 120 ± 7 in RG). CMPS-SF revealed higher medians (P= 0.038) at the Mextub and 12 h time points for the LG [5 (3-6) and 1 (0-2)] than for the RG [5 (2-5) and 0 (0-1)].Discussion: Pain was excluded as a possible explanation for the difference presented for HR in both groups because, moderate pain is considered when more than two cardiorespiratory parameters show an increase of at least 20% in relation to baseline values, which did not occur in this study. Indeed, most animals were walking at 0.5 h after extubation and, in many cases, this occurred before the collection of data for the postoperative period. This may have influenced the results since exercise releases catecholamines and increases HR. Moreover at 4 h after extubation, most animals were asleep. As metabolism decreases during sleep, expected that HR would also decrease and that was indeed the case. Regarding CMPS-SF, the way the patients walks was the item that most contributed to the high score found for the Mextub time point because it's impossible to be performed seconds after extubation. As the reluctance to move occurred only immediately after extubation, the values obtained at the Mextub time point are more likely to be due to an anesthetic residual effect and not to the pain stimulus itself. When the groups were compared, the median values obtained at the LG were greater than RG at the Mextub and 12 h postoperative time points.  There was no need for analgesic rescue differing from those in literature that reported the need for analgesic rescue in 50% of the animals. Those study established a CMPS-SF score of 3.3 as indicative for analgesic rescue whereas our research established a score of 7. Tumescence solutions with lidocaine or ropivacaine provide equivalent postoperative analgesia for at least 12 h.