Effectiveness of nuchal ligament autograft in the healing of an experimental superficial digital flexor tendon defect in equid.

This study aimed to investigate nuchal ligament (NL) autograft on experimental tendon defect healing in donkeys. Eight healthy donkeys were used. The left forelimb's superficial digital flexor (SDF) tendon was assigned as treatment, and the right forelimb was allocated as the control group (without surgical intervention). A 3×1.5 cm segment of the funicular part of the NL was excised. A full thickness defect created in the treatment tendon and was grafted with the excised NL. The following parameters were evaluated in 120 days postoperatively: clinical, ultrasonography, radiography, histopathology, biomechanical properties, and scanning and electronic transmission microscopy. There were no significant changes observed in the neck angle so that it was confirmed this treatment regimen preserved the head and neck situation without any considerable neck swelling. Weight-bearing in gait and trot was similar between both forelimbs at the end of the study. Mild to moderate adhesion was detected in the dorsal surface of the SDF tendon. There was no significant difference in the echogenicity and fiber alignment, respectively, on days 90 and 120 after surgery. Treatment significantly amplified the collagen diameter and enhanced the collagen fibril diameter and density considerably compared to the NL. The transplanted tissue was mostly in the remodeling or maturation phase, on day 120 postoperatively. It seems that the NL is biocompatible, almost biodegradable, and effective in tendon healing without metaplasia or tissue rejection.

Effects of Medetomidine, Dexmedetomidine and their combination with Acepromazine on the intraocular pressure (IOP), tear secretion and pupil diameter in dogs.

BACKGROUND: A great number of sedatives and anaesthetics have been used to perform surgeries or routine ophthalmologic examinations in animals and sometimes the combination of these medicines has more suitable effects than each one alone. OBJECTIVES: This paper aims to explore the main effects of Medetomidine + Acepromazine, Dexmedetomidine + Acepromazine on intraocular pressure, tear secretion and pupil diameter. METHODS: To accomplish the aforementioned aim, 32 adult dogs (aged one-to-three-years-old) were clinically examined. Dogs were divided into four groups consisting of group DA, Dexmedetomidine (5 µg/kg) + Acepromazine (0.05 mg/kg); Group D, Dexmedetomidine (5 µg/kg); Group M, Medetomidine (10 µg/kg); Group MA, Medetomidine (10 µg/kg) + Acepromazine (0.05 mg/kg). The ocular factors including tear production, pupil diameter and intraocular pressure of both right and left eyes were first measured and then recorded in each dog at time T0 (-15 min). Afterwards, the drugs were administered intramuscularly, based on which the ocular factors were re-measured at T1 (+5 min), T2 (+15 min) and T3 (+20 min). All four groups showed a reduction in intraocular pressure, which was significant in DA, D and M groups. RESULTS: Furthermore, there was a fluctuation in the amount of tear secretion in DA and D groups (increase and then decrease), as well as a significant reduction in M and MA groups. Decreasing in pupil diameter also occurred in all four groups, but the reduction was significant only in DA and MA groups. CONCLUSION: According to the results obtained, as the changes caused by the systemic administration of the above drug compounds did not exceed the physiological range, it can be concluded that these combinations could be utilized as suitable sedatives or pre-anaesthetic compounds in the eye surgeries.

Intraperitoneal administration of lidocaine or tramadol alone or in combination on postoperative pain after ovariohysterectomy in dogs.

The present prospective randomized experimental study aimed to assess the intraperitoneal (ip) administration of lidocaine or tramadol, alone or in combination, on postoperative pain management following ovariohysterectomy in dogs. Eighteen healthy female mixed-breed dogs, aged 1-2 years, weighed 16.7 ± 3.8 kg, were used. Animals were sedated with acepromazine (0.1 mg/kg, intramuscular). Forty minutes later, anaesthesia was induced through intravenous titration with diazepam (0.5 mg/kg) and ketamine (10 mg/kg) and maintained with isoflurane 1.5%. Afterwards, ovariohysterectomy was performed, and prior to the closure of the linea alba, animals received lidocaine containing epinephrine (8.8 mg/kg, ip) in group L, tramadol (4 mg/kg, ip) in group T and lidocaine containing epinephrine (8.8 mg/kg, ip) plus tramadol (4 mg/kg, ip) in the LT group. Cortisol, vital signs and pain scoring systems were evaluated at different time points. Vital signs did not change among the groups. Cortisol level in the LT group significantly decreased compared to the L and T groups one, three and six hours after surgery. Pain scores also did not change among the groups based on Sammarco and Simple descriptive (SDS) scoring method. However, pain scores in the LT group were higher than the two other groups according to the University of Melbourne pain scale (UMPS) and the short form of Glasgow pain scale (CMPS-SF). According to the obtained results, the combination of lidocaine and tramadol seemed to be able to provide better analgesia compared with their separate administration. Therefore, combined intraperitoneal administration of lidocaine (8.8 mg/kg) and tramadol (4 mg/kg) with a final volume of (0.2 ml/kg) following ovariohysterectomy is recommended.

The effects of doxapram on haematology, serum biochemical parameters and erythrocyte oxidant/ antioxidant status in dogs anaesthetized with propofol.

The present prospective randomized experimental study was designed to determine the effects of doxapram on haematological, serum biochemical and antioxidant status in dogs after propofol anaesthesia. Twenty-four healthy male mixed breed dogs, aged 1-2 years, weighing 20.4 ± 2.6 kg was studied. Each dog was anaesthetized twice, with at least one week for washout. Animals were sedated with acepromazine (0.1 mg/kg) intramuscularly. Forty minutes later, anaesthesia was induced using intravenous (IV) propofol (4 mg/kg) titration and maintained for 30 min by propofol (0.2 mg kg-1  min-1 ). After propofol was discontinued, doxapram (2 mg/kg) hydrochloride was administrated IV in PD treatment while an equal volume of saline was administrated in PS treatment. Blood parameters were analysed in four times: immediately before sedation (T1), after treatment (T2), after complete recovery (T3) and 24 hr later (T4). Haematological assessments revealed no significant difference between treatments except in haematocrit which was significantly reduced at T4 (24 hr later) in PD. A decreasing trend of all haematological variables was observed after doxapram administration until recovery, except monocyte, mean corpuscular haemoglobin, red blood cell distribution width and platelet count. Serum urea, creatinine, glucose, cholesterol, direct bilirubin concentration and alanine aminotransferase activity were not changed following doxapram administration compared to the PS treatment. After doxapram administration, Creatinine (T3), Albumin (T2) and Protein (T2 & T3) decreased while Glucose (T2 & T3) and BT (T3) increased. Antioxidant parameters measured showed no difference between treatments or time. Doxapram (2 mg/kg) IV did not induce any major negative effects on haematological, serum biochemical variables and oxidant/antioxidant status in dogs after propofol anaesthesia.

Effect of phentolamine mesylate on regression of lidocaine-epinephrine epidural anaesthesia in sheep.

OBJECTIVE: To determine the impact of epidural phentolamine on the duration of anaesthesia following epidural injection of lidocaine-epinephrine. STUDY DESIGN: Blinded randomized experimental study. ANIMALS: A group of 12 adult ewes weighing 25.7 ± 2.3 kg and aged 8-9 months. METHODS: All sheep were administered epidural lidocaine (approximately 4 mg kg-1) and epinephrine (5 µg mL-1). Of these, six sheep were randomized into three epidural treatments, separated by 1 week, administered 30 minutes after lidocaine-epinephrine: SAL: normal saline, PHE1: phentolamine (1 mg) and PHE2: phentolamine (2 mg). The other six sheep were administered only epidural lidocaine-epinephrine: treatment LIDEP. Each injection was corrected to 5 mL using 0.9% saline. Noxious stimuli were pinpricks with a hypodermic needle and skin pinch with haemostatic forceps to determine the onset and duration of sensory and motor block. Heart rate, noninvasive mean arterial pressure (MAP), respiratory rate and rectal temperature were recorded. RESULTS: The onset times were not different among treatments. Duration of sensory block was significantly shorter in SAL (57.5 ± 6.2 minutes), PHE1 (60.7 ± 9.0 minutes) and PHE2 (62.0 ± 6.7 minutes) than in LIDEP (81.7 ± 13.4 minutes) (p < 0.05). Duration of motor blockade was significantly shorter in PHE1 (59.4 ± 5.4 minutes) and PHE2 (54.3 ± 4.0 minutes) than in SAL (84.8 ± 7.0 minutes) and LIDEP (91.5 ± 18.2 minutes) (p < 0.01). MAP in PHE2 was decreased at 10 minutes after administration of phentolamine (p < 0.05). CONCLUSION AND CLINICAL RELEVANCE: Epidural administration of 5 mL normal saline after epidural injection of lidocaine-epinephrine reduced the duration of sensory but not motor block in sheep. Epidural administration of phentolamine diluted to the final volume of 5 mL diminished both the duration of sensory and motor block in sheep administered epidural lidocaine-epinephrine.

Cardiopulmonary effects during anaesthesia induced and maintained with propofol in acepromazine pre-medicated donkeys.

OBJECTIVE: To evaluate the cardiopulmonary effects of anaesthesia induced and maintained with propofol in acepromazine pre-medicated donkeys. STUDY DESIGN: Prospective experimental study. ANIMALS: Six healthy male donkeys weighing 78-144 kg. METHODS: Donkeys were pre-medicated with intravenous (IV) acepromazine (0.04 mg kg(-1) ). Ten minutes later, anaesthesia was induced with IV propofol (2 mg kg(-1) ) and anaesthesia maintained by continuous IV infusion of the propofol (0.2 mg kg(-1)  minute(-1) ) for 30 minutes. Baseline measurements of physiological parameters, and arterial blood samples were taken before the acepromazine administration, then 5, 15, 30, 45, and 60 minutes after the induction of anaesthesia. Changes from baseline were analysed by anova for repeated measures. RESULTS: When compared with baseline (standing) values, during anaesthesia heart rate increased throughout: significant at 5 (p = 0.001) and 15 (p = 0.015) minutes. Mean arterial blood pressure increased significantly only at 15 minutes (p < 0.001). Respiratory rate and arterial pH did not change significantly. PaO2 was lower throughout anaethesia, but this only reached significance at 15 minutes (p = 0.041). PaCO2 was statistically (but not clinically) significantly reduced at the times of 30 (p = 0.02), 45 (p = 0.01) and 60 (p = 0.04). Rectal temperature decreased significantly at all times of the study. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of propofol by the continuous infusion rate for the maintenance of anaesthesia resulted in stable cardiopulmonary effects and could prove to be clinically useful in donkeys.

Analgesic effects of tramadol hydrochloride administered via caudal epidural injection in healthy adult cattle.

OBJECTIVE: To evaluate the extent and duration of analgesic effects of tramadol hydrochloride administered epidurally in standing healthy adult cattle. Animals-5 mixed-breed adult female cattle. PROCEDURES: 1, 2, or 3 mg of tramadol/kg was injected into the first intercoccygeal space of each cow in random order at 1-week intervals. Analgesia, sedation, and ataxia were scored on scales of 0 (no effect) to 3 (complete analgesia or extreme sedation or ataxia) at 5-minute intervals beginning 5 minutes prior to injection and ending 120 minutes after injection. Analgesia was evaluated on the basis of response to pinprick stimuli over 9 caudal regions. Heart rate, respiratory rate, rectal temperature, and rumen motility were assessed 5 minutes before and at predetermined intervals for 120 minutes after tramadol injection. RESULTS: Analgesia induced via tramadol administration was dose dependent (eg, mean duration of complete analgesia at the perineum was 18 minutes when cows received the 1 mg/kg dose, 60 minutes when cows received the 2 mg/kg dose, and 92 minutes when cows received the 3 mg/kg dose). Slight to mild sedation and ataxia were observed when cows received 2 or 3 mg of tramadol/kg. No significant tramadol-associated changes in heart rate, respiratory rate, rectal temperature, or rumen motility were detected. CONCLUSIONS AND CLINICAL RELEVANCE: Caudal epidural tramadol administration induced analgesia with slight to mild sedation and ataxia in cows. Analgesia in affected regions after administration of 2 or 3 mg of tramadol/kg was considered sufficient to allow common surgical procedures to be performed in standing cattle.