Pain Management

Opioids Out, Cannabis In Negotiating the Unknowns in Patient Care for Chronic Pain

Summary:

“Unless the nation develops an increased tolerance to chronic pain, reduction in opioid prescribing leaves a vacuum that will be filled with other therapies.” Consideration for the pharmacological, social and legal role of cannabis as an alternative for prescribing opioids.

Conclusion:

The prescribing of opioid therapy for chronic noncancer pain advanced unchecked until opioid-related adverse events and other consequences reached epic proportions. To ensure the medical community does not repeat this mistake with cannabis, physicians should balance the need to keep pace with the swiftly evolving cultural, social, and legal climate surrounding cannabis use for pain with the imperative to guide practice with sound science.

Author & Journal:Choo, Esther K. et al, JAMA, 2016

Long-term treatment with carprofen of 805 dogs with osteoarthritis.

Summary:

The pain-relieving effect of carprofen and tolerance to the drug were investigated in 805 dogs that were lame as a result of osteoarthritis. The dogs were of different breeds, ages and bodyweights and of both sexes, and were selected from 51 veterinary clinics. Each dog was treated orally by its owner with 4 mg/kg carprofen for 84 consecutive days.

Conclusion:

Twenty-four dogs were removed from the study because of side effects, and 55 left the study for reasons unrelated to the treatment. The condition of the dogs and the benefit of the treatmentwere evaluated by the veterinary surgeons and the owners after 14 days, and at the end of the period of treatment, when 194 of the dogs (26.7 per cent) were no longer lame, and 357 (49.2 per cent) had improved. The period for which the dogs had been lame before entering the study significantly (P<0.01) affected the results and the rate of improvement. Too much exercise during the 84 days of treatment caused some dogs to relapse.

Author & Journal:Mansa S, et al, Vet Rec 2007;160:427-430

Efficacy of Venlafaxine in Neuropathic Pain: A Narrative Review of Optimized Treatment.

Summary:

The prevalence of neuropathic pain is high in the general population, and high priority is given to the management of this pain condition. The treatment of neuropathic pain remains challenging, despite the publication of national and international recommendations. The purpose of this narrative review of venlafaxine (VLX) is to provide a better knowledge of the pharmacology of this drug and a clearer view of its efficacy and tolerability in neuropathic pain.

Conclusion:

Eleven were randomized clinical trials, and the comparator was placebo in 8 studies. Nine studies reported that VLX was effective against neuropathic pain. However, among the trials, only one against placebo included a large number of patients with >200 participants and one against prégabaline and carbamazepine had >200 patients. Most of the adverse events reported in the selected studies were consistent with known adverse events of VLX, and most were mild to moderate. However, most studies were of very short duration.

Author & Journal:Trouvin AP, et al, Clin Ther. 2017 Jun;39(6):1104-1122

Examination of synovial fluid and serum following intravenous injections of hyaluronan for the treatment of osteoarthritis in dogs.

Summary:

A randomized, blinded, prospective clinical trial was performed to determine the effects of intravenous (i.v.) administration of hyaluronan sodium (HA) on serum glycosaminoglycans (GAG) concentrations, synovial fluid (SF) hyaluronan concentrations and viscosity in dogs treated for unilateral rupture of the cranial cruciate ligament.

Conclusion:

Data were analyzed using a Wilcoxon sign rank test (p < 0.05). Mean +/- SD viscosity (cP) was significantly higher (p = 0.011) in SF obtained from the intact stifle (450 +/- 604.1) than injured (54.8 +/- 60.8) prior to surgery. Mean +/- SD HA concentrations (ug/ml) were significantly higher (p = 0.02) in synovial fluid obtained from the injured stifles (281.4 +/- 145.9) than intact stifles (141.6 +/- 132.5). No significant difference was noted within or between treatment groups in SF viscosity, HA concentrations, or serum GAG concentrations at any time following surgery. Stifles with cranial cruciate ligament insufficiency had significant alterations in SF viscosity and HA concentrations.

Author & Journal:Canapp SO, et al, Vet Comp Orthop Traumatol 2005;18:19-174

2015 AAHA/AAFP Pain Management Guidelines for Dogs and Cats

Summary:

The included pain management “guidelines continue the trend in all branches of medicine toward evidence-based consensus statements that address key issues in clinical practice. Although not a review article, this compilation is a force multiplier for the busy practitioner, consolidating in a single place current recommendations and insights from experts in pain management.”

Conclusion:

“Behavioral changes are the principal indicator of pain and its resolution, for which there are now several validated, clinical scoring instruments. Pain is not an isolated event but instead exists either as a continuum of causation, progression, and resolution or as a chronic condition. Thus treatment of pain should consist of a continuum of care in the form of anticipatory analgesia through the anticipated pain period followed by longer-term or even chronic treatment that relies on periodic reassessment of the patient’s response.”

Author & Journal:Epstein, Mark et al, Journal of the American Animal Hospital Association, 2016

Nonsteroidal antiinflammatory drugs: a review.

Summary:

The increasing use of nonsteroidal antiinflammatory drugs (NSAIDs) in small animals has resulted in the development of new and innovative additions to this class of drugs. Examples of NSAIDs now available for use in small animals include aspirin, etodolac, carprofen, ketoprofen, meloxicam, deracoxib, and tepoxalin.

Conclusion:

The purposes of this article are to review the pathophysiology of prostaglandin synthesis and inhibition, the mechanisms of action, pharmacokinetics, pharmacological effects, and potential adverse reactions of aspirin and the newly released NSAIDs.

Author & Journal:Curry SL, et al, J Am Anim Hosp Assoc 2005; 41:298-309

Systemic administration of glycosaminoglycan polysulphate (arteparon) provides partial protection of articular cartilage from damage produced by meniscectomy in the canine.

Summary:

Bilateral medial meniscectomy was undertaken in 14 mature beagles. Another two underwent arthrotomy (sham-operated controls).

Conclusion:

The results indicated that Arteparon provided some protective effect to AC in the meniscectomised compartment as demonstrated histologically by reduced surface fibrillation, diminished chondrocyte cloning, and maintenance of alcianophilia. The levels of PGs and hexuronate-protein ratios in medial AC of drug-treated meniscectomised animals were found to be comparable to sham controls, whereas these parameters in the nondrug-treated meniscectomized group were depressed.

Author & Journal:Hannan N, et al, J Orthop Res 1987; 5:47-49

Effect of intraarticular hyaluronan injection on synovial fluid hyaluronan in the early stage of canine post-traumatic osteoarthritis.

Summary:

To determine how the quantity and molecular weight of synovial fluid hyaluronan (HA) within the synovial fluid (SF) of osteoarthritis (OA) joints is affected by intraarticular injection of HA.

Conclusion:

Intraarticular injection of HA did not alter the volume of SF or molecular weight of HA in SF of OA canine knees, nor did it restore the HA concentration to that of normal canine SF.

Author & Journal:Smith GN, et al, J Rheumatol 2001;28:1341-1346

Outpatient Oral Analgesics in Dogs and Cats Beyond Nonsteroidal Anti-inflammatory Drugs

Summary:

This article evaluates the current literature on oral analgesics and analgesic adjuncts in dogs and cats. An overview of how dosing recommendations are made covering controlled clinical trials, experimental study design, and pharmacokinetic studies is included.

Conclusion:

The weight of evidence for each drug [Polysulfated glycosaminoglycans, Amantadine, Tramadol, Gabapentin, Pregabalin, Codeine, Hydrocodone, Amitriptyline, Venlafaxine, Duloxetine, Glucosamine and chondroitin, Morphine, Oxycodone, Methadone] is reviewed and compared with the gold standard, controlled clinical trials. Other evidence such as experimental studies, extrapolation of pharmacokinetic studies, and case reports/series is also considered.

Author & Journal:KuKanich, Butch, Veterinary Clinics of North America: Small Animal Practice, 2013