Dynamic Interactive Visual Analogue Scale Research Articles

Evaluation of three doses of oral trazodone and their impact on handling, activity, and physiological parameters in rabbits: a prospective, blinded, randomized cross-over study.

No study has determined the minimal effective dose of trazodone required to induce behavioral changes and its safety profile in rabbits. Therefore, this study aimed to determine the minimal effective dose of trazodone to improve compliance to handling, and to evaluate associated changes in motor activity, physiological and arterial blood gas parameters. Eight intact female New Zealand White rabbits (2-month-old; 1.66 ± 0.12 kg) were included in this prospective, blinded, randomized cross-over study. After a 10-day acclimation, rabbits randomly received placebo or trazodone 10, 20 or 30 mg/kg orally (PLAC, TRAZ10, TRAZ20, TRAZ30) with a 1-week wash-out period. Compliance scoring (dynamic interactive visual analog scale; DIVAS), activity levels measured with accelerometry (T0-T600), physiological parameters (temperature, heart, and respiratory rates), and arterial blood gas parameters (up to T240) were evaluated. Compliance scores, accelerometry, physiological and arterial blood gas parameters and hypoxemia prevalence (PaO2 <60 mmHg) were analyzed using linear mixed models and Chi-squared tests, respectively (P<0.05). When compared with PLAC, DIVAS scores were significantly higher at T80-120, T40-120 and T120-200 in TRAZ10, TRAZ20 and TRAZ30 post-administration, respectively. When compared with baseline, DIVAS scores were significantly higher from T80-160, T40-240 and T80-200 in TRAZ10, TRAZ20 and TRAZ30, respectively. All other parameters were not significantly different. In TRAZ30, hypoxemia was observed in 2/8 rabbits (P=0.104). In conclusion, oral trazodone improved rabbit compliance at all studied dosages, especially 20 mg/kg improved rabbit compliance without decreasing motor activity or causing hypoxemia.

Intraperitoneal and incisional ropivacaine did not improve postoperative analgesia after multimodal anaesthesia compared with saline in dogs undergoing ovariohysterectomy.

Intraperitoneal administration of local anaesthetics may reduce postoperative pain after ovariohysterectomy in dogs. The aim of this prospective, randomised, blinded, placebo-controlled clinical trial was to compare postoperative analgesia and opioid requirements after intraperitoneal and incisional administration of ropivacaine versus 0,9 % NaCl (saline). Forty-three client-owned dogs were enrolled in the study and anaesthetised using a standardized protocol that included premedication with acepromazine (0,03-0,05 mg/kg) and dexmedetomidine (0,01 mg/kg) intramuscularly. Anaesthesia was induced with propofol titrated to effect and ketamine (1 mg/kg) intravenously and maintained with isoflurane in oxygen. The analgesic regimen included carprofen (4 mg/kg) subcutaneously and morphine (0,2 mg/kg) intravenously. Depending on group assignment, each dog received either an intraperitoneal and incisional splash with ropivacaine (2 mg/kg and 1 mg/kg, respectively) (group R), or an equal volume of saline (group S). Buprenorphine (0,02 mg/kg) was administered intramuscularly once the uterus was removed. Sedation and pain were assessed 0,5, 1, 2, 4, 6 and 8 hours after extubation using a sedation scale, the short form of the Glasgow Composite Pain Scale (CMPS-SF) and a dynamic interactive visual analogue scale (DIVAS). Postoperatively, buprenorphine (0,01 mg/kg) was administered intravenously if dogs scored 6/24 on CMPS-SF. The ordinal mixed model showed no difference in pain scores between groups. Fisher's exact test showed no significant difference in postoperative buprenorphine requirements between group S (3/22 dogs) and group R (1/21 dogs) at the doses used. In addition, lower sedation scores were associated with higher DIVAS scores. In this multimodal analgesic protocol, ropivacaine could not improve analgesia compared to saline.

Randomized single-blinded prospective comparison between ozone therapy and electroacupuncture for canine thoracolumbar disk disease

Ozone therapy has been used to control pain in animals. Moreover, electroacupuncture (EA) has been effective in neurological recovery and pain control in dogs with thoracolumbar discopathy. EA was compared with Ozone applied at acupuncture points in dogs with signs of thoracolumbar disk disease. Chondrodystrophic mongrel dogs, with lesion scores between 1 and 4, were randomly divided into groups: EA (n = 13) - electroacupuncture at BL20, BL23, ST36, KID3 and BL60 and dry needle in lumbar Bai Hui, and OZO (n = 15) - paravertebral application of 3 mL ozone (20 μg / mL) at BL20, BL23, lumbar Bai Hui, ST36, and KID3/BL60, both groups with weekly applications. No significant differences were observed between groups in weekly blind pain assessments using a dynamic interactive visual analog scale, and neurological assessments using a numerical-functional scale. Both groups showed a progressive improvement in pain control and neurological condition, which was observed when comparing the group's EA and OZO in dogs with all lesion scores. The time of return to locomotion (days) of dogs scored 3 and 4, between groups EA (10.6 ± 5.4) and OZO (14.5 ± 15.7), had no significant differences. Ozone therapy was effective to control pain and motor rehabilitation and sensory functions of dogs with thoracolumbar discopathy signs, just as electroacupuncture. Ozone application was a quick and easy-to-handle treatment. Paravertebral and subcutaneous routes did not require anesthesia or other advanced imaging technology, besides being safe and effective.

Evaluation of the Analgesic Efficacy of Undiluted Intraperitoneal and Incisional Ropivacaine for Postoperative Analgesia in Dogs after Major Abdominal Surgery.

Recommendations for intraperitoneal (IP) and incisional (INC) administration of local anaesthetics after visceral surgery exist, but evidence is scarce. This prospective, randomized, blinded, controlled, clinical trial compared postoperative pain in dogs undergoing major abdominal surgery. Sixteen client-owned dogs were anaesthetized with a standardized balanced protocol including opioids and received either 2 mg/kg ropivacaine IP (0.27 mL/kg) and a 1 mg/kg INC splash (0.13 mL/kg) or equal volumes of saline. Influence of the treatment on heart rate (HR) and postoperative pain was assessed using the Short Form of the Glasgow Composite Pain Scale (GCPS-SF), a dynamic interactive visual analogue scale (DIVAS) and mechanical nociceptive threshold testing (MNT). Data was tested with mixed ordinal regression and log linear mixed models for 0.5, 1, 2, 3, 4, 6, 8, 10 and 12 h after extubation. Rescue analgesia was given to 3/8 dogs after ropivacaine and 0/8 dogs after saline. GCPS-SF and MNT were not different between groups. DIVAS was slightly higher after ropivacaine (odds increased by 5.44 (confidence interval (CI) 1.17-9.96, p = 0.012)), and HR after ropivacaine was 0.76 * that after saline (CI 0.61-0.96, p = 0.02) with no effect of time (p = 0.1). Undiluted ropivacaine IP and INC was not beneficial for postoperative analgesia.

A randomized, prospective, masked clinical trial comparing an opioid-free vs. opioid-sparing anesthetic technique in adult cats undergoing ovariohysterectomy.

This study aimed to compare the analgesic effects of an injectable protocol using multimodal analgesia with or without opioids in cats undergoing ovariohysterectomy (OVH). Thirty-two healthy cats were enrolled in a prospective, blinded, randomized trial after the caregiver's written consent. Cats received a combination of ketamine (4 mg/kg), midazolam (0.25 mg/kg) and dexmedetomidine (40 μg/kg), and either buprenorphine (20 μg/kg) or saline (same volume as buprenorphine) intramuscularly [opioid-sparing (OSA) and opioid-free anesthesia (OFA) groups, respectively]. Intraperitoneal bupivacaine 0.25% (2 mg/kg) and meloxicam (0.2 mg/kg subcutaneously) were administered before OVH. Atipamezole (400 μg/kg intramuscularly) was administered at the end of surgery. Pain and sedation were evaluated using the Feline Grimace Scale (FGS) and a dynamic interactive visual analog scale, respectively. Intravenous buprenorphine was administered as rescue analgesia if FGS scores ≥ 0.39/1. Statistical analysis included repeated measures linear mixed models, Fisher's exact test and Bonferroni adjustments when appropriate (p < 0.05). Twenty-seven cats were included. The prevalence of rescue analgesia was lower in OSA (n = 0/13) than in OFA (n = 5/14) (p = 0.04). The FGS scores (least square means and 95% CI) were higher in OFA at 1 [2.0 (1.3-2.7)] and 2 h [2.2 (1.5-2.9)] than baseline [0.7 (0.0-1.4)], but not in OSA. Sedation scores were not significantly different between groups. Opioid-free injectable anesthesia was appropriate for some cats using a multimodal approach. However, a single dose of intramuscular buprenorphine eliminated the need for rescue analgesia and assured adequate pain management after OVH in cats.

Selected highlights from other journals.

CARPROFEN has been extensively studied for both pre- and postoperative pain control in dogs, while, until recently, metamizole was only approved as an injectable formulation for the veterinary market. This blinded, randomised study aimed to compare the analgesic efficacy and duration of a new slow-release formulation of metamizole with carprofen for dogs undergoing ovariohysterectomy. Dogs were randomly assigned into two groups; one group received 50 mg/kg of metamizole, the other was given 4 mg/kg of carprofen, and the same medications were repeated 24 and 48 hours later. The dogs were later sedated using medetomidine and methadone, followed by anaesthesia induced with propofol. Assessment of postoperative sedation and analgesia was performed by one blinded observer, using a visual analogue scale, a dynamic interactive visual analogue scale, the Glasgow composite pain scales (GCPS) and a mechanical nociceptive threshold device. Plasma concentrations of the test drugs were also analysed. Twenty dogs, 10 in each group, completed the study. Half an hour after the procedure, sedation scores were significantly higher in the carprofen group. Of the …

Preperitoneal ropivacaine infusion versus epidural ropivacaine–morphine for postoperative analgesia in dogs undergoing ovariohysterectomy: a randomized clinical trial

ObjectiveTo assess the effect of continuous wound infusion (CWI) with preperitoneal ropivacaine on postoperative analgesia and compare it with the epidural administration of ropivacaine and morphine in bitches undergoing ovariohysterectomy. Study designA parallel, randomized, clinical, prospective and nonblinded study. AnimalsA group of 38 Greyhound bitches. MethodsIn the catheter group (CathG), CWI with ropivacaine 1% (1 mg kg–1 + 0.8 mg kg–1 hour–1) was applied to the preperitoneal space over the surgical incision. In the epidural group (EpiG), ropivacaine 0.5% (1.3 mg kg–1) and morphine (0.1 mg kg–1) were epidurally administered. Occipital-coccygeal length was used to calculate the volume for the epidural. Pain was scored using a dynamic interactive visual analogue scale (DIVAS) and Glasgow composite measure pain scale–short form (CMPS-SF) before anaesthesia and at 2, 4, 6, 18, 21 and 24 hours after extubation. Incisional sensitivity using a dynamometer (MWTs-incision) was evaluated simultaneously. Plasma ropivacaine and cortisol concentrations, degree of sedation, motor blockade and response to interdigital clamping were measured or assessed. A two-way mixed analysis of variance and a Mann–Whitney U test were used to analyse data; p < 0.05. ResultsNo differences were detected in the DIVAS (p = 0.301), CMPS-SF (p = 0.600) scores, MWTs-incision measurements (p = 0.257) and cortisol values (p = 0.878) between the groups. Rescue analgesia was required in two dogs, one in each group, at 2 hours. Sedation, motor blockade and negative response to interdigital clamping were detected in EpiG at 2, 4 and 6 hours. Mean plasma ropivacaine values were higher in CathG (0.475 ± 0.164 ng mL–1) than in EpiG (0.184 ± 0.213 ng mL–1; p = 0.001). Conclusion and clinical relevanceCompared with epidural ropivacaine and morphine, CWI with preperitoneal ropivacaine is an effective analgesic technique for postoperative pain management in bitches undergoing ovariohysterectomy without motor blockade.

Preemptive effect of amantadine as adjuvant in postoperative analgesia of ovaryhisterectomy in dogs

This study aimed to evaluate the preemptive analgesic effect of amantadine on postoperative pain control in female dogs that underwent ovariohysterectomy. Twenty female dog were randomly assigned to two groups of ten. The control group (CONTROL) received oral placebo capsules, while the amantadine (AMANT) group received 5 mg/kg of oral amantadine one hour before sedation. All the animals were premedicated with 3 mg/kg (IM) meperidine, induced with propofol and maintained with isofluorane. The transanesthetic physiological parameters were recorded, and postoperative pain was evaluated every hour after extubation for six hours with the Dynamic Interactive Visual Analog Scale (DIVAS) and mechanical nociceptive threshold (MNT) and when the necessary analgesic rescue was administered (morphine, 0.2 mg/kg (IM)). During the surgical procedure, there was no significant difference in the variables measured between the two groups. Regarding postoperative pain assessment, there was a significant difference in the DIVAS score (p = 0.004) between the groups, in which AMANT required fewer rescues than did CONTROL (p = 0.03). The MNT was significantly higher ​​in AMANT than in CONTROL (p = 0.03). The results suggested that the preoperative administration of amantadine decreased analgesic requirement in female dogs that underwent elective ovariohysterectomy.

Sedative effects of acepromazine in combination with nalbuphine or butorphanol, intramuscularly or intravenously, in healthy cats: a randomized, blinded clinical trial.

The aim of this study was to compare the sedative effects in cats administered acepromazine-nalbuphine and acepromazine-butorphanol, intramuscularly (IM) and intravenously (IV), and the occurrence of adverse cardiorespiratory effects. Forty-six cats were randomly divided into four groups and administered acepromazine (0.05 mg/kg) combined with nalbuphine (0.5 mg/kg) or butorphanol (0.4 mg/kg), IV (ACP-NALIV and ACP-BUTIV groups, respectively) or IM (ACP-NALIM and ACP-BUTIM groups, respectively). Sedation scores, ease of intravenous catheter placement (simple descriptive scale [SDS] scores), physiologic variables, venous blood gases and the propofol dose required for anesthetic induction were recorded. Mild sedation was observed in all groups approximately 30 mins after treatment administration (timepoint T1, prior to propofol administration). Sedation scores at T1 increased above baseline in all groups (P <0.05), but no significant difference was observed among groups. Dynamic interactive visual analogue scale sedation scores (range 0-100 mm) recorded at T1 were (median [interquartile range]): ACP-NALIM, 12 (10-12); ACP-NALIV, 11 (6-16); ACP-BUTIM, 11 (7-14); and ACP-BUTIV, 12 (7-19). Overall, SDS scores did not change from baseline at T1 and there was no significant difference among groups. The propofol dose did not differ among groups. Blood gases remained within the reference intervals for cats. Significant decreases from baseline were detected for all groups in systolic arterial pressure (SAP). Mean ± SD values at T1 were (mmHg): ACP-NALIM, 108 ± 13; ACP-NALIV, 102 ± 10; ACP-BUTIM, 97 ± 13; and ACP-BUTIV, 98 ± 21. Arterial hypotension (SAP <90 mmHg) was recorded at T1 in 0/11, 1/13, 4/11 and 5/11 cats in groups ACP-NALIM, ACP-NALIV, ACP-BUTIM and ACP-BUTIV, respectively, and was further exacerbated after the induction of anesthesia with propofol. In healthy cats administered acepromazine-nalbuphine and acepromazine-butorphanol, IM and IV, the degree of sedation was mild regardless of the protocol and the route of administration. The main adverse effect observed was a reduction in arterial blood pressure.

Evaluation of nalbuphine, butorphanol and morphine in dogs during ovariohysterectomy and on early postoperative pain

ObjectiveTo evaluate the effects of nalbuphine, butorphanol and morphine combined with acepromazine on intraoperative and early postoperative pain management in dogs anesthetized for ovariohysterectomy. Study designProspective, randomized blinded clinical study. AnimalsA total of 48 healthy female dogs of different breeds, aged 1–6 years, weighing (mean ± standard deviation) 14.5 ± 4.8 kg. MethodsDogs were randomly assigned into four groups to be intravenously administered nalbuphine (0.5 mg kg–1; group N0.5), nalbuphine (1.0 mg kg–1; group N1.0), butorphanol (0.4 mg kg–1; group B0.4) or morphine (0.2 mg kg–1; group M0.2) combined with acepromazine (0.02 mg kg–1) prior to propofol and isoflurane for anesthesia. Heart rate (HR), respiratory rate, systolic arterial pressure and rectal temperature (RT) were recorded at time points during anesthesia. A dynamic interactive visual analog scale applied in three phases (DIVAS I, II and III) and the modified Glasgow composite measure pain scale were used to assess pain before premedication and 1, 2, 3, 4, 5 and 6 hours after extubation. Administration of rescue analgesia was recorded. ResultsAt the left ovarian pedicle ligation, HR was higher in N1.0 than in B0.4 (p = 0.020). RT decreased significantly by the end of surgery in N0.5 (p = 0.043) and B0.4 (p = 0.010). Rescue analgesia was administered postoperatively over 6 hours to eight, seven, nine and 10 dogs in N0.5, N1.0, B0.4 and M0.2, respectively (p = 0.57). DIVAS II was higher in B0.4 than in N1.0 at 2 and 3 hours (p = 0.038 and p = 0.002, respectively) and N0.5 at 3 hours (p = 0.003). Conclusions and clinical relevanceAt the doses used, all premedication protocols provided insufficient intraoperative analgesia, with minimal clinical differences between groups. No premedication provided satisfactory analgesia in the first 6 hours postoperatively.

Postoperative Analgesic Effects of Laserpuncture and Meloxicam in Bitches Submitted to Ovariohysterectomy.

Background: This prospective, randomised and blind study investigated the efficacy of laserpuncture for postoperative pain management in dogs. Method: Sixteen bitches were sedated with acepromazine and randomly treated before ovariohysterectomy with meloxicam 0.2 mg·kg−1 intramuscular or laserpuncture (wavelength 904 mm, frequency 124 Hz, potency 10 Joules, 100 s in each acupoint). Anaesthesia was performed with propofol, isoflurane/O2, and fentanyl. The Glasgow Composite Measure Pain Scale (GCMPS) and Dynamic Interactive Visual Analog Scale (DIVAS) were used to evaluate postoperative pain before and for 24 h after surgery. Morphine was administrated as rescue analgesia when pain scores were ≥3.33 (GCMPS). Differences between treatments, time points, and amount of rescue analgesia between groups were investigated by the Mann–Whitney test and the area under the curve (AUC) for GCMPS, Friedman, and Chi-squared tests, respectively (p < 0.05). Results: Dogs treated with laserpuncture presented lower GCMPS AUC for 24 h and lower GCMPS scores at 2 and 4 h postoperatively (p = 0.04). Three dogs treated with meloxicam required postoperatively rescue analgesia against none treated with laserpuncture. Conclusions: In this preliminary study, laserpuncture mitigated postoperative pain in dogs following ovariohysterectomy, and the technique is a promising adjunct to perioperative pain management in dogs undergoing soft tissue surgery.

The analgesic effects of buprenorphine (Vetergesic or Simbadol) in cats undergoing dental extractions: A randomized, blinded, clinical trial.

This study aimed to evaluate the analgesic efficacy of two dosage regimens using two different concentrations of buprenorphine in cats undergoing dental extractions. Twenty-three cats with oral disease (8.2 ± 2.2 years old; 4.9 ± 0.9 kg) were included in a prospective, blinded, randomized clinical trial. Cats randomly received either Simbadol (1.8 mg/mL; 0.24 mg/kg, subcutaneously, every 24h: SG, n = 11) or Vetergesic (0.3 mg/mL; 0.02 mg/kg, intramuscularly, every 8h: VG, n = 12) throughout the study. They were admitted at day 0, underwent oral examination/radiographs/treatment under general anesthesia (buprenorphine-propofol-isoflurane-meloxicam-local anesthetic blocks) at day 1 and discharged at day 4. Sedation and pain were scored using the dynamic interactive visual analog scale (day 1) and the Glasgow Composite Measure Pain Scale-Feline (CMPS-F; up to postoperative 8 hours at day 1, 8 am, 4 pm and midnight at days 2 and 3, and 8 am at day 4), respectively. Rescue analgesia was administered with hydromorphone (0.05 mg/kg intravenously on day 1 or 0.1 mg/kg intramuscularly after day 2) when CMPS-F ≥ 5. Resentment defined as any type of escape behavior associated with aversion to drug administration was recorded. Sedation and pain scores, the prevalence of rescue analgesia and resentment during drug administration were analyzed using linear mixed models and Fisher’s exact test, respectively (p < 0.05). Pain and sedation scores were not significantly different between groups. Sedation scores were significantly higher up to postoperative 2 hours in both groups. Pain scores in SG and VG were significantly higher up to postoperative 8 hours and 8 am of day 2, respectively, than baseline. Prevalence of rescue analgesia and resentment were not significantly different between groups (SG: 27.3%, VG: 33.3% and SG: 0%, VG: 25%, respectively). Simbadol produced similar analgesic effects to Vetergesic without resentment during drug administration.

The analgesic effects of buprenorphine (Vetergesic or Simbadol) in combination with carprofen in dogs undergoing ovariohysterectomy: a randomized, blinded, clinical trial

BackgroundBuprenorphine is a potent lipophilic opioid analgesic that is largely used in the multimodal treatment of acute pain. Simbadol (buprenorphine hydrochloride) is the first and only FDA-approved high-concentration formulation of buprenorphine for use in cats. The aim of this study was to evaluate the analgesic efficacy of carprofen in combination with one of two commercial formulations of buprenorphine (Simbadol and Vetergesic, 1.8 mg/mL and 0.3 mg/mL, respectively) in dogs undergoing ovariohysterectomy. Twenty-four dogs were included in a randomized, prospective, controlled, clinical trial. Patients were randomly divided into 2 groups as follows. Dogs were premedicated with acepromazine (0.02 mg/kg) and either 0.02 mg/kg of Vetergesic or Simbadol intramuscularly (Vetergesic group – VG; Simbadol group – SG, respectively; n = 12/group). General anesthesia was induced with propofol and maintained with isoflurane in 100% oxygen. Carprofen (4.4 mg/kg SC) was administered after induction of anesthesia. Heart rate, respiratory rate, blood pressure, pulse oximetry, pain scores using the Glasgow Composite Pain Scale Short Form (CMPS-SF), sedation scores using a dynamic interactive visual analogue scale and adverse events were evaluated before and after ovariohysterectomy by an observer who was unaware of treatment administration. If CMPS-SF scores were ≥ 5/20, dogs were administered rescue analgesia (morphine 0.5 mg/kg IM). Statistical analysis was performed using linear mixed models and Fisher’s exact test (p < 0.05).ResultsPain and sedation scores and physiological parameters were not significantly different between treatments. Three dogs in VG (25%) and none in SG (0%) required rescue analgesia (p = 0.109). Adverse effects (i.e. vomiting and melena) were observed in two dogs in SG and were thought to be related to stress and/or nonsteroidal anti-inflammatory drug toxicity.ConclusionsThe administration of buprenorphine with carprofen preoperatively provided adequate postoperative analgesia for the majority of dogs undergoing OVH without serious adverse events. Prevalence of rescue analgesia was not significantly different between groups; however, it could be clinically relevant and explained by a type II error (i.e. small sample size). Future studies are necessary to determine if analgesic efficacy after Simbadol and Vetergesic is related to individual variability or pharmacokinetic differences.

A comparison between methadone and buprenorphine for perioperative analgesia in dogs undergoing ovariohysterectomy

To investigate whether preoperative methadone provides superior perioperative analgesia compared to buprenorphine in dogs undergoing ovariohysterectomy. Eighty female dogs were recruited to an assessor-blinded, randomised, clinical trial. Dogs received a premedication dose of 0·05 mg/kg acepromazine or 10μg/kg medetomidine combined with either 0·3mg/kg methadone or 20 μg/kg buprenorphine intramuscularly. Anaesthesia was induced with propofol and maintained with isoflurane. Pain was assessed using two scoring schemes (a dynamic interactive visual analogue scale and the short form of the Glasgow Composite Pain Scale) before premedication, 30 minutes later and every hour for 8hours after premedication. If indicated, rescue analgesia was provided with methadone. Meloxicam was administered after the final assessment. The area under the curve for change in pain scores over time and the requirement for rescue analgesia were compared between groups. Groups premedicated with buprenorphine had significantly higher pain scores than those premedicated with methadone. There was no interaction between opioid and sedative for any outcome measure. Rescue analgesia was required by significantly more dogs premedicated with buprenorphine (45%) than that of methadone (20%). At the doses investigated, methadone produced superior postoperative analgesia compared to buprenorphine in dogs undergoing ovariohysterectomy.

Intraperitoneal bupivacaine with or without incisional bupivacaine for postoperative analgesia in dogs undergoing ovariohysterectomy

ObjectiveIntraperitoneal (IP) bupivacaine provides postoperative analgesia in dogs undergoing ovariohysterectomy (OHE) alone or in combination with incisional (INC) bupivacaine. This study investigated whether the combination of INC and IP bupivacaine is superior to IP bupivacaine alone. Study designProspective, randomized, blinded clinical study. AnimalsThirty-nine privately owned dogs undergoing OHE, aged 25 ± 23 months and weighing 11.8 ± 5.7 kg. MethodsDogs were premedicated with acepromazine (0.05 mg kg−1) and morphine (0.5 mg kg−1) intramuscularly (IM); anaesthesia was induced with propofol and maintained with isoflurane in oxygen. Carprofen (4 mg kg−1) was administered subcutaneously (SC) after intubation. Bupivacaine (3 mg kg−1) IP was administered before complete closure of the linea alba to all dogs. Dogs were randomly assigned into two groups: group B received bupivacaine (n = 20; 1 mg kg−1) and group S received saline (n = 19; 0.2 mL kg−1) INC as a subcutaneous ‘splash’ before skin closure. Postoperative analgesia was assessed with a dynamic interactive visual analogue scale, the short form of the Glasgow Composite Pain Scale, and mechanical nociceptive threshold (MNT) measurement at 0.5, 1, 2, 4, 6, 8, 12 and 20 hours after surgery by one blinded observer. Parametric data were tested using t-test; nonparametric data were analysed using the two-sample Wilcoxon test (p < 0.05). ResultsThere was no significant difference between groups with regard to age, weight, surgical and anaesthetic duration, incision length, sedation and pain scores. MNT values decreased in both groups at all time points as compared with the baseline. No dog required rescue analgesia. No postoperative complications were observed. Conclusion and clinical relevanceBupivacaine IP and carprofen SC after morphine IM did provide satisfactory postoperative analgesia in dogs undergoing OHE with the anaesthetic protocol used. There appears to be no clinical advantage to adding bupivacaine INC. Neither protocol could prevent the development of primary hyperalgesia.

Analgesic efficacy of intraperitoneal administration of bupivacaine in cats.

Objectives The aim of this study was to evaluate the analgesic efficacy of intraperitoneal (IP) bupivacaine in cats undergoing ovariohysterectomy (OVH). Methods Forty-five cats were included in a randomized, prospective, blinded study after owners' written consent was obtained. The anesthetic protocol included acepromazine-buprenorphine-propofol-isoflurane. A ventral midline incision was made and cats (n = 15/group) were administered either IP saline 0.9% (negative and positive control groups; NG and PG, respectively) or IP bupivacaine (2 mg/kg; bupivacaine group; BG). Cats in the PG received meloxicam (0.2 mg/kg SC). An OVH was performed and postoperative pain was evaluated using a dynamic interactive visual analog scale (DIVAS), the UNESP-Botucatu multidimensional composite pain scale (MCPS) and mechanical nociceptive thresholds (MNT) for up to 8 h after the end of surgery. Postoperative sedation was evaluated using DIVAS. Rescue analgesia was provided with buprenorphine and/or meloxicam. Repeated measures linear models and a Cochran-Mantel-Haenszel test were used for statistical analysis ( P <0.05). Results There was a significant effect of treatment on the number of times rescue analgesia was administered ( P = 0.002) (PG, n = 2, 13%; NG, n = 12, 80%; BG, n = 4, 27%) with the number of rescues being higher in the NG group than in the PG ( P = 0.0004) and BG ( P = 0.02) groups. The DIVAS, MCPS and MNT were significantly different when compared with baseline values at different time points; however, data were not significantly different among groups. Conclusions and relevance Treatments PG and BG produced similar analgesia in terms of pain scores, number of times rescue analgesia was administered and MNT. Based on rescue analgesia, IP administration of bupivacaine provides analgesia in cats after OVH.

Agreement between veterinary students and anesthesiologists regarding postoperative pain assessment in dogs

ObjectiveTo determine the levels of agreement among first- and second-year veterinary students and experienced anesthesiologists in assessing postoperative pain in dogs from video-recordings. Study designCross-sectional study. SubjectsTwenty-seven veterinary students, five anesthesiologists and 13 canine clinical patients. MethodsPrior to their enrolment in a core anesthesia course, veterinary students volunteered to watch 13 90 second videos of dogs. Dogs were hospitalized in an intensive care unit after a variety of surgical procedures. Students were asked to score the level of the dogs’ pain using the Dynamic Interactive Visual Analog Scale and the Short Form of the Glasgow Composite-Measure Pain Scale. The same videotapes were scored by five board-certified anesthesiologists. The differences and agreement between the ratings of anesthesiologists and students, and first- and second-year students were determined with Mann-Whitney U-tests and Fleiss’ or Cohen’s kappa, respectively. ResultsPain scores assigned by students and anesthesiologists differed significantly (p < 0.01). Students assigned higher pain scores to dogs that were given low pain scores by anesthesiologists, and lower pain scores to dogs deemed to be in more pain by anesthesiologists. On average, students assigned higher scores on both scales. Conclusions and clinical relevanceVeterinary students early in their training assigned pain scores to dogs that differed from scores assigned by experienced anesthesiologists.

Comparison of a new metamizole formulation and carprofen for extended post-operative analgesia in dogs undergoing ovariohysterectomy

A newly developed slow-release tablet formulation of metamizole was compared with carprofen for post-operative analgesia in dogs undergoing ovariohysterectomy. Twenty-three dogs were randomly assigned to one of two groups, and administered 50 mg/kg metamizole PO (Group M) or 4 mg/kg carprofen PO (Group C) 1 h before anaesthetic induction and 24 and 48 h later. Anaesthesia was induced with propofol and maintained with isoflurane and fentanyl, after premedication with 0.005 mg/kg medetomidine and 0.3 mg/kg methadone IM. A blinded observer assessed post-operative sedation, and analgesia using a visual analogue scale, a dynamic interactive visual analogue scale, the Glasgow composite pain scale (GCPS), and a mechanical nociceptive threshold device (T = 0.5, 1, 2, 4, 8, 12, 18, 21, 24, 36, 45, 60 and 70 h after surgery). Rescue methadone was administered if the GCPS was >6/24 in ambulatory dogs, or >5/20 in non-ambulatory dogs. Plasma concentrations of test drugs were quantified.The dose range for metamizole was 39–56 mg/kg. At T = 0.5 h sedation scores were significantly higher in Group C and GCPS scores were significantly higher in Group M. Three dogs required rescue methadone (Group M, n = 1; Group C, n = 2). Vomiting occurred post-operatively in 45% of dogs in Group M. Carprofen and metamizole were both well absorbed; peak concentrations occurred within 4–24 h, and 4–16 h for carprofen and metamizole, respectively. Both drugs provided adequate analgesia of similar duration. No side effects were observed with carprofen while vomiting was frequent following administration of metamizole.

Laser Acupuncture for Postoperative Pain Management in Cats.

The aim of this study was to evaluate laser acupuncture as an adjuvant for postoperative pain management in cats. Twenty cats, undergoing ovariohysterectomy, were sedated with intramuscular (IM) ketamine (5 mg kg−1), midazolam (0.5 mg kg−1), and tramadol (2 mg kg−1). Prior to induction of anaesthesia, the subjects were randomly distributed into two groups of 10 cats: Laser: bilateral stomach 36 and spleen 6 acupoints were stimulated with infrared laser; Control: no acupuncture was applied. Anaesthesia was induced using intravenous propofol (4 mg kg−1) and maintained with isoflurane. Postoperative analgesia was evaluated by a blinded assessor for 24 h following extubation using the Dynamic Interactive Visual Analogue Scale and Multidimensional Composite Pain Scale. Rescue analgesia was provided with IM tramadol (2 mg kg−1), and the pain scores were reassessed 30 min after the rescue intervention. If the analgesia remained insufficient, meloxicam (0.2 mg kg−1 IM, single dose) was administered. Data were analyzed using t-tests, the Mann-Whitney test, and the Friedman test (P < 0.05). The pain scores did not differ between groups. However, postoperative supplemental analgesia was required by significantly more cats in the Control (5/10) compared with the Laser group (1/10) (P = 0.038). Laser acupuncture reduced postoperative analgesic requirements in cats undergoing ovariohysterectomy.

The effects of an intravenous bolus of dexmedetomidine following extubation in a mixed population of dogs undergoing general anaesthesia and surgery

An observer blinded, placebo controlled study evaluated the effects of 62.5μg/m2 dexmedetomidine administered IV on recovery from isoflurane anaesthesia in dogs. Forty-four healthy dogs, weighing 1.8–19.95kg, presented for surgery that was expected to cause mild to moderate pain were studied. All were premedicated with 125μg/m2 dexmedetomidine and 20μg/kg buprenorphine IM. Anaesthesia was induced with propofol and maintained with isoflurane. Non-steroidal anti-inflammatory drugs and local anaesthetics were administered as appropriate. Immediately prior to extubation dogs were treated with dexmedetomidine 62.5μg/m2 (group D) or an equivalent volume of heparinised saline (S). Assessments of heart rate, respiratory rate, pain (short form Glasgow composite pain scale [SF-GCPS], dynamic interactive visual analogue scale [DIVAS]), sedation (simple descriptive scale [SDS], DIVAS) and mechanical nociceptive threshold (MNT) were performed immediately before premedication, 20min later, at the time of test drug administration (T0) and at 15–30min intervals for four hours (T240min). Recovery quality was scored 0 – 3 (SDS). Data were analysed with Student’s t and Mann–Whitney U tests, two-way ANOVA and Fisher’s exact test.Significantly fewer poor quality recoveries were observed in group D (D 2 [1–3]; S 2 [0–3]; P=0.02), however, sedation was increased in group D compared to group S from T15 to T150min (P=0.0001). Pain scores were lower in group D compared to group S from T15 to T120min (P=0.001), but the requirement for additional analgesia in the first 4h following extubation was not different between groups. Dexmedetomidine may decrease the incidence of poor quality anaesthetic recoveries in dogs.