SEPTEMBRE 2018 - ACTUS DOULEURS

 

1/ Epidural anesthesia and analgesia in small animal practice: An update

Fernando Garcia-PereiraVet. J., In Press, Accepted Manuscript,
Available online 11 September 2018

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Résumé

Epidural anesthesia is a commonly performed technique in both human and veterinary medicine.
The technique is relatively simple following appropriate training and provides anesthesia and analgesia for acute and chronic pain.
Several drug combinations have been administered by this route with variable success and duration.
Multiple techniques to guide or confirm correct epidural needle placement are discussed in this article, as well as anatomical features of the epidural space, effect of drug volume and concentration, and adverse effects of the technique in small animal practice. 
This article is not an exhaustive review of the literature, but an update of some new findings over the last decade.


2/ Comparison between methadone and buprenorphine within the QUAD protocol for perioperative analgesia in cats undergoing ovariohysterectomy

Meera Shah, David Yates, James Hunt, Jo Murrell
J. Fel. Med. Surg., First Published September 14, 2018

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Résumé

The aim of this study was to investigate the analgesic efficacy of methadone vs buprenorphine within the QUAD protocol for anaesthesia in cats undergoing ovariohysterectomy.

Methods

One hundred and twenty cats were recruited to an assessor-blinded, randomised clinical trial.
Cats received either methadone (5  mg/m2) or buprenorphine (180  µg/m2) combined with ketamine, midazolam and medetomidine intramuscularly.

Anaesthesia was maintained with isoflurane in oxygen.
Atipamezole was administered at extubation.
Pain was assessed using the feline Composite Measure Pain Scale (CMPS-F), a dynamic interactive visual analogue scale (DIVAS) and mechanical nociceptive threshold (MNT). Sedation, pain, heart rate and respiratory rate were measured prior to QUAD administration, before intubation, and 2, 4, 6 and 8 h post-QUAD administration.

If indicated by the CMPS-F, rescue analgesia was provided with 0.5 mg/kg of methadone administered intramuscularly.

Meloxicam was administered after the last assessment.
Differences in pain scores between groups were compared using a two-way repeated-measures ANOVA and requirement for rescue analgesia was compared using a χ2 test.

Results

Cats administered methadone had lower CMPS-F scores over time (P = 0.04).
Eighteen of 60 cats required rescue analgesia in the methadone group vs 29/60 in the buprenorphine group (P = 0.028). All cats that received rescue analgesia required it within 6 h post-QUAD administration.
There were no differences between groups in MNT or pain measured using the DIVAS.

Conclusions and relevance

Methadone produced clinically superior postoperative analgesia for the first 8 h after neutering than buprenorphine when used within the QUAD protocol.


3/ New therapies to relieve pain

The search for more efficient and safer alternatives to opioid pain killers

EMBO Reports (2018) e46925 - Philip Hunter

Résumé

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Opioids are a largely efficient medication for relieving severe pain and are prescribed for a wide variety of indications including metastatic cancer, arthritis, neuropathy or post‐surgical pain.
These drugs target opioid receptors to produce effects similar to morphine and include moderately strong painkillers such as oxycodone and hydrocodone (Vicodin), and strong drugs like fentanyl, which resembles opium‐derived morphine and heroin.
The great efficiency of opioids in treating severe pain has also been the major drawback for longer‐term use given their addictive power.
This does not matter for short‐term use, for instance to ease post‐operative pain, or terminal cancer when the primary requirement is to relieve suffering.
Yet, the addictive side effect has become a huge societal problem; in addition, opioids do not work against all types of chronic pain, including some of the most severe cases such as cancer‐induced bone pain or some cases of neuropathy resulting from nerve damage.

These problems have spurred efforts to develop new drugs for treating pain with some success in developing derivatives with reduced side effects.
The other major avenue of research is the identification of relevant pain pathways or protein binding sites including those involved in the placebo effect.

> Article accessible à l’adresse: http://embor.embopress.org/content/early/2018/09/17/embr.201846925


 
Thierry Poitte