Efficacy of tramadol for postoperative pain management in dogs: systematic review and meta-analysis

Influence of intravenous fentanyl or dexmedetomidine infusions, combined with lidocaine and ketamine, on cardiovascular response, sevoflurane requirement and postoperative pain in dogs anesthetized for unilateral mastectomy

OBJECTIVE

To compare the effects of constant rate infusions (CRI) of fentanyl or dexmedetomidine, combined with lidocaine and ketamine, on cardiovascular response during surgery, sevoflurane requirement and postoperative pain in dogs undergoing mastectomy.

STUDY DESIGN

Prospective, randomized, blinded, clinical trial.

ANIMALS

A total of 29 female dogs with mammary tumors.

METHODS

Premedication consisted of intramuscular acepromazine and morphine. General anesthesia was induced with intravenous propofol and maintained with sevoflurane. Dogs were randomized to be administered intravenous DLK [dexmedetomidine 1 μg kg-1 loading dose (LD) and 1 μg kg-1 hour-1; lidocaine 2 mg kg-1 LD and 3 mg kg-1 hour-1; ketamine 1 mg kg-1 LD and 0.6 mg kg-1 hour-1; n = 14] or FLK (fentanyl 5 μg kg-1 LD and 9 μg kg-1 hour-1; same doses of lidocaine and ketamine; n = 15) during anesthesia. Cardiorespiratory variables and end-tidal sevoflurane (Fe'Sevo) were recorded during surgery. The number of dogs administered ephedrine to treat arterial hypotension [mean arterial pressure (MAP) < 60 mmHg] was recorded. Meloxicam was administered to both groups. Postoperative pain and rescue analgesia requirement were assessed for 24 hours using the short form of the Glasgow Composite Measure Pain Scale. Data were compared using a mixed effects model or a Mann-Whitney test.

RESULTS

More dogs required ephedrine in FLK than in DLK (67% versus 7%). Heart rate was not significantly different between groups, whereas lower values of MAP (p ≤ 0.01) and Fe'Sevo (p = 0.018) were observed in FLK than in DLK. Rescue analgesia was administered to 2/15 dogs in FLK and 0/14 dogs in DLK.

CONCLUSIONS AND CLINICAL RELEVANCE

Based on the cardiovascular response during surgery, intraoperative infusions of FLK and DLK provided adequate antinociception. Infusion of DLK provided greater stability of blood pressure. Both protocols resulted in minimal need for additional analgesia within 24 hours postoperatively.

Improving access to melarsomine therapy: treating canine heartworm infection in a high-volume, outpatient community clinic setting

BACKGROUND

Models that provide high-quality veterinary care for more affordable prices are emerging, but not well documented outside of wellness and preventative care. Effective treatment guidelines for heartworm disease have been developed by the American Heartworm Society; however, not all owners are able to access treatment due to the high costs associated with sick and emergency care services.

METHODS

To increase access to high-quality adulticidal treatment of canine heartworm disease, we developed and implemented a technician-leveraged heartworm treatment protocol for high-volume, outpatient community clinic settings based on the American Heartworm Society guidelines. Modifications were few and included limited pre-treatment blood work, pre-injection sedation, post-injection pain medication, and a reduced exercise restriction period. We monitored retention rates for 556 dogs throughout treatment, evaluated treatment success (defined as no antigen detection 9 months post treatment) for patients that returned for post-treatment antigen testing, and reported on adverse reactions and therapy adherence throughout treatment.

RESULTS

Of the patients that began adulticide therapy, 539/556 (97%) successfully completed the three-injection series. No microfilariae were detected in 99% (428/433) of those who returned for post-injection microfilaria testing. Among those that returned for or reported the results of post-injection antigen testing, no antigen was detected for 99% (245/248) and no microfilariae were detected for 99.5% (200/201). During the course of treatment, 483/539 (90%) of patients experienced at least one adverse reaction, with the most frequently reported types being behavioral and injection site reactions. 25/539 (4.6%) of owners sought additional medical care for adverse reactions at some point during the treatment course. The overall mortality rate was 1.3% (7/556).

CONCLUSIONS

This study represents the first evaluation of a heartworm treatment protocol optimized for implementation in a high-volume, outpatient community clinic setting. Our findings align with those previously reported in private practice or tertiary referral centers, illustrating that through the inclusion of pre-treatment blood work, employing short-acting or reversible sedatives, ensuring proper analgesia, minimizing the use of ancillary diagnostics, reducing the duration of in-clinic monitoring while focusing on outpatient care, and maximizing technician involvement, we can deliver effective and safe melarsomine therapy at a more affordable cost to pet owners.

Pelvic limb anesthesia and analgesia in dogs undergoing tibial plateau leveling osteotomy (TPLO): A survey of board-certified anesthesiologists

OBJECTIVE

To report the locoregional anesthesia and analgesia preferences of veterinary anesthesiologists for use in dogs undergoing a TPLO and determine any association with specialty college, time from board-certification, or employment sector.

STUDY DESIGN

Cross sectional study.

SAMPLE POPULATION

Diplomates of the American (ACVAA) and European (ECVAA) Colleges of Veterinary Anesthesia and Analgesia.

METHODS

An electronic survey was distributed to diplomates and responses were used to determine associations between preferred methods.

RESULTS

The survey response rate was 28% (141/500) with 69% (97/141) of ACVAA diplomates and 31% of diplomates with ECVAA (44/141) certification. Peripheral nerve block (PNB) was preferred by 79% (111/141) of all diplomates, lumbosacral epidural (LE) by 21% (29/141), and peri-incisional infiltration (PI) by <1% (1/141). There was no association (p = .283) with specialty college. There was an association (p < .001) with time from board-certification with increased preference for LE when >10-years from certification and PI preferred by only those board-certified >20-years ago. There was an association with employment sector (p = .003) with more academic diplomates preferring LE. Anesthesiologists reported that treatment decisions were affected by various factors including time pressure and surgeon influence.

CONCLUSION

Diplomates of ACVAA and ECVAA prefer PNB as the locoregional method of pelvic limb anesthesia in dogs undergoing TPLO. A greater percentage of newer and private practice diplomates prefer PNB while a larger percentage of senior and academic diplomates prefer LE. Decision making is multifactorial and includes perceived time pressure and surgeon influence.

CLINICAL SIGNIFICANCE

Veterinary anesthesiologists prefer and frequently use PNB in dogs undergoing TPLO and surgeon influence may affect their chosen treatment.

Blinded, randomized, placebo-controlled study of the efficacy of bupivacaine liposomal suspension using static bodyweight distribution and subjective pain scoring in dogs after tibial plateau leveling osteotomy surgery

OBJECTIVE

To compare the analgesic effect of surgical wound infiltration with liposomal bupivacaine (LB) to saline placebo in dogs after tibial plateau leveling osteotomy (TPLO).

STUDY DESIGN

Blinded, randomized, placebo-controlled clinical prospective study.

ANIMALS

Fifteen client-owned dogs receiving LB and 17 dogs receiving an equivalent volume of saline placebo, all with confirmed unilateral cranial cruciate ligament insufficiency.

METHODS

Preoperatively and up to 48 h after surgery, Glasgow Composite Measure Short Form (CMPS-SF) pain scores were assigned and using a weight distribution platform, static bodyweight distribution (%BW_dist ) to the operated limb was measured. Postoperatively, dogs also received carprofen 2.2 mg/kg subcutaneously every 12 h. Rescue analgesia was provided. Treatment success was defined as not requiring rescue analgesia over the 48-h postoperative period.

RESULTS

There was no difference between treatment success, postoperative opioid consumption, CMPS-SF pain scores, or %BW_dist in dogs that received surgical wound infiltration with LB compared with those receiving saline placebo, following TPLO. There was no linear correlation between CMPS-SF pain scores and %BW_dist .

CONCLUSION

For the population of dogs that underwent TPLO and received postoperative carprofen at our institution, LB did not provide an analgesic effect discernable by success/failure analysis, CMPS-SF pain scores, or %BW_dist measurement using a weight distribution platform, compared with saline placebo.

CLINICAL SIGNIFICANCE

LB may not provide detectable analgesia during the first 48 h for dogs recovering from TPLO and receiving only postoperative carprofen.

Comparative growth dynamics of bacterial and fungal contaminants in bupivacaine liposomal injectable suspension, bupivacaine 0.5%, and propofol

OBJECTIVE

To determine whether bupivacaine liposomal injectable suspension (BLIS) supports microbial growth when artificially inoculated and to evaluate liposomal stability in the face of this extrinsic contamination as evidenced by changes in free bupivacaine concentrations.

STUDY DESIGN

A randomized, prospective in vitro study in which three vials of each BLIS, bupivacaine 0.5%, and propofol were individually inoculated with known concentrations of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans (n = 36) to quantify bacterial and fungal growth was conducted. Over 120 hours, aliquots from contaminated vials were withdrawn, plated, and incubated to determine microbial concentrations. High-pressure liquid chromatography (HPLC) was used to evaluate free bupivacaine concentrations over time in BLIS. Data were analyzed using a mixed effects model with multiple comparisons.

SAMPLE POPULATION

Twelve vials of each BLIS, bupivacaine 0.5%, and propofol.

RESULTS

BLIS did not support significant growth of Staphylococcus aureus or Candida albicans at any time. BLIS supported significant growth of Escherichia coli and Pseudomonas aeruginosa beginning at the 24 hour time point. Bupivacaine 0.5% did not support significant growth of any organisms. Propofol supported significant growth of all organisms. Free bupivacaine concentrations changed minimally over time.

CONCLUSION

Bacterial and fungal contaminant growth in artificially inoculated BLIS is organism dependent. BLIS supports significant growth of Escherichia coli and Pseudomonas aeruginosa. Extra-label handling of BLIS should only be undertaken with caution and with adherence to strict aseptic technique.

Treatment of Pain in Rats, Mice, and Prairie Dogs

Recent myomorph and scuiromorph rodent analgesia studies are reviewed and evaluated for potential clinical application. Differences between laboratory animal studies and clinical use in diseased animals are discussed. Analgesia classes reviewed include local anesthetics, nonsteroidal anti-inflammatories, acetaminophen, opioids, and adjuvants such as anticonvulsants. Routes of administration including sustained-release mechanisms are discussed, as are reversal agents. Drug interactions are reviewed in the context of beneficial multimodal analgesia as well as potential adverse effects. Dosage recommendations for clinical patients are explored.

Clinical features and management of snake bites in 70 dogs in Korea

BACKGROUND

Snakebites remain a devastating and life-threatening environmental hazard. While the management of snakebites has been well described in humans, few clinical data and guidelines exist for dogs, especially in Korea.

OBJECTIVES

This retrospective study evaluated the clinical features of 70 dogs with snakebite wounds in Korea.

METHODS

The medical records of 72 dogs that presented to three animal hospitals from June 2008 to July 2021 were reviewed; among these, 70 dogs that met the inclusion criteria were enrolled. Their signalment, history, clinical signs, physical examination, blood analysis, treatment, and prognosis were also evaluated.

RESULTS

Of 70 dog owners, 35 (50%) witnessed the bite, with a mean time between bite and hospital presentation of 9.7 ± 4.1 h in 58 dogs. Blood smears were evaluated in 45 dogs, of which 28 (62%) showed echinocytosis. Anemia and acute kidney injury were found in 21 (29%) and 2 dogs (3%), respectively. A total of 37 dogs (53%) were hospitalized, 5 (7%) of which died.

CONCLUSIONS

The most significant finding was the high prevalence of echinocytosis. The data from this retrospective study could inform the management of dogs bitten by snakes in Korea.

Intensity of perioperative analgesia but not pre-treatment pain is predictive of survival in dogs undergoing amputation plus chemotherapy for extremity osteosarcoma

The purpose of this bi‐institutional retrospective study was to determine whether, in dogs treated with limb amputation and adjunctive chemotherapy for osteosarcoma, oncologic outcomes are impacted by either: (1) baseline cancer pain severity, or (2) the approaches used for perioperative pain management. Data were extracted from the medical records of 284 dogs that underwent both limb amputation and chemotherapy (carboplatin and/or doxorubicin) between 1997 and 2017 for localized (non‐metastatic) osteosarcoma of the appendicular skeleton. Kaplan–Meier survival curves and Cox proportional hazard (PH) models were used to determine the impact that retrospectively scored baseline pain levels (high vs. low) and various analgesic and local anaesthetic treatments had on both metastasis‐free survival and all‐cause mortality. For the entire population, the median disease free interval and median overall survival times were 253 and 284 days, respectively. Baseline pain was rated as “low” in 84 dogs, and “high” in 190 dogs; pain severity had no detectable effect on either metastasis‐free survival or all‐cause mortality. When accounting for the potential influences of known prognostic factors, dogs treated with what was characterized as a high‐intensity perioperative analgesic plan (including both a non‐steroidal anti‐inflammatory drug [NSAID] and a bupivacaine‐eluting soaker catheter placed at the amputation site) had a higher probability of survival than dogs treated with a low‐intensity perioperative analgesic plan (neither an NSAID, nor a soaker catheter); the median overall survival times were 252 and 378 days, respectively (hazard ratio: 2.922; p = .020).

Comparative Multimodal Palliative efficacy of gabapentin and tramadol By Using Two Pain Scoring Systems in Cats Undergoing Ovariohysterectomy

The analgesic efficacy of the gabapentin-tramadol combination was compared with meloxicam-tramadol and tramadol perioperative analgesic regimens in cats brought to the clinic for ovariohysterectomy. Thirty adult cats belonging to comparable demographics (age, body weight), were enrolled into a randomized, blinded study after due consent from their owners into four treatment groups. A Gabapentin-Tramadol group (GT-group, n = 10), Meloxicam-Tramadol group (MT-group, n = 10), and a Tramadol group (T-group, n = 10) were formed. Gabapentin capsules at 50 mg were administered orally 2 hours before surgery while the rest received a placebo dose. Tramadol (2 mg/kg, IM) and meloxicam at (0.2 mg/kg, SC) were injected immediately prior to anesthetic premedication. Anesthetic protocol involved premedication with ketamine and xylazine, while anesthesia was induced using propofol. Inhalant isoflurane anesthesia was used to maintain a surgical plane. GT group scored lower on IVAS as well as CPS than MT group, and T group for up to 8 hours after surgery. The mechanical nociceptive threshold remained higher (98±0) for up to 12 hours postoperatively a nd serum cortisol concentrations remained significantly lower during the 24hr period. The addition of gabapentin to the tramadol regimen significantly improved analgesia and mechanical nociceptive threshold than when used on its own.

Evaluation of prescribing practices for gabapentin as an analgesic among veterinary professionals

OBJECTIVE

To describe the prescribing practices for gabapentin as an analgesic within the veterinary community.

STUDY DESIGN

Anonymous online voluntary survey.

POPULATION

A total of 718 veterinarians within the United States and Canada, including general practitioners and diplomates of the American Colleges of Veterinary Anesthesia and Analgesia, Emergency and Critical Care, Surgery and Internal Medicine.

METHODS

An anonymous online survey was used to gather information about individual prescribing practices for gabapentin including frequency of use, reasons for prescribing and procedures for authorizing refill requests. Questions specific to gabapentin covered mechanisms of action, perceptions of efficacy and the potential for abuse in people. Dunn's test for multiple comparisons and pairwise Mann-Whitney U test were used to evaluate relationships between veterinary specialty and survey responses.

RESULTS

A total of 718 veterinarians responded to the survey, 528 (73.5%) answered all questions of the survey to completion. Frequency of prescribing was high with 365/529 (69.0%) of respondents prescribing gabapentin as an analgesic on a daily or weekly basis. Surgeons and general practitioners used gabapentin significantly more frequently than other groups, with surgeons more likely to prescribe gabapentin for postoperative pain. The most common reason [254/517 (49.1%)] survey respondents prescribed gabapentin as an analgesic was because administration of a non-steroidal anti-inflammatory medication was contraindicated for that animal. The majority of survey respondents [362/527 (68.7%)] considered the abuse potential of gabapentin to be low in people.

CONCLUSIONS AND CLINICAL RELEVANCE

Veterinary prescribing practices for gabapentin closely mirrored that of human physicians, with gabapentin being prescribed frequently and for uses largely unrelated to its labeled indication. The perception of the potential for abuse of gabapentin is low within the veterinary community.