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Pet pain management

It is now scientifically proven that our pets feel pain and also suffer from it. The mechanisms of pain perception in animals differ only insignificantly from those in humans. Therefore, professional pain treatment should also be a matter of course in animals. This applies both to acute pain after accidents or operations and to chronic pain such. B. in degenerative diseases of the musculoskeletal system.

Problem of pain detection

It is often difficult to even recognize pain in animals, because it is part of the natural protective mechanism not to show pain. This is especially true for "prey" such as rabbits, guinea pigs and other small mammals as well as birds. Those who appear visibly ill or handicapped are easy prey. As a result, many birds and pets fluff themselves up and appear healthy and well fed, although they are sick and already very emaciated.

There are good criteria for assessing acute pain in dogs and cats, e. B. acute lameness, pain on palpation and a change in posture. In the case of chronic pain, the symptoms are usually more subtle and develop insidiously over a longer period of time, so that they are not associated with pain but are often attributed to the animal's increasing age.

It has only recently become known that around a third of all cats between the ages of six and seven and 90% of all cats over the age of twelve suffer from painful osteoarthritis. The elbow joints are usually affected, followed by the hip and knee joints.

Possible signs of chronic pain can include:

  • all deviations from normal individual behavior, e.g. B. apathy, withdrawal, but also aggressiveness and restlessness

  • declining stamina, decreased activity and performance
  • Avoidance of fast races, lack of playing behavior
  • Problems getting up, climbing stairs, and jumping
  • Morning stiffness
  • stiff gait (especially in cats)
  • shaggy and unkempt fur
  • limited cleaning behavior (especially with cats)
  • Uncleanliness, unclean rooms (especially with cats)
  • Loss of appetite, weight loss
  • Muscular atrophy
  • Gnawing and licking painful parts of the body
  • decreased mobility of the joints
  • Whine, groan

If chronic pain is suspected, a trial of pain medication can help confirm the diagnosis. In the case of long-term treatment, documentation in the form of a pain diary has proven itself. The animal owner should determine the degree of pain at least once a week in order to obtain meaningful values ​​for assessing the course of the disease. Especially with chronic degenerative joint diseases, acute attacks with pain can occur again and again, in which the long-term medication has to be adjusted.

Particular challenge with pets

In pets (e.g. rabbits, guinea pigs, chinchillas, mice, hamsters, rats) it is much more difficult to detect chronic pain than in dogs and cats for the reasons mentioned above. Only attentive pet owners who know their animals very well perceive the often subtle symptoms:

  • decreased activity, hiding in the cottage
  • tense gait, scuttling
  • tense posture, arched back
  • Press your stomach on the floor
  • stubbornly staring into the corner
  • bristling, unkempt fur
  • soiled and reddish discolored inner corners of the eyes (so-called spectacle eyes) in rats

  • Attacks or being excluded by cage mates
  • isolate yourself from the group
  • aggressiveness
  • Automutilation (self-mutilation), especially in rabbits
  • Eating young animals
  • reduced food intake
  • Weight loss

The same difficulties apply to birds as to the pets mentioned above. On closer observation, however, the following symptoms are usually noticeable:

  • shaggy, fluffed plumage
  • abnormally trusting behavior
  • reduced food intake
  • reduced activity up to drowsiness
  • Pulling up the lower eyelid
  • decreased singing

Documenting the weight history and the exact amount of food consumed is often the best way to assess chronic pain in pets and birds. Because a reduced feed intake or a weight loss with the same feed intake can indicate a painful process.

Which painkillers are suitable?

As the first choice for chronic pain such as B. chronic degenerative joint diseases are non-steroidal anti-inflammatory drugs (NSAID, nonsteroidal anti-inflammatory drugs), as there are NSAIDs suitable for long-term or long-term therapy with only minor side effects. Since animals can react very differently to different non-steroidal anti-inflammatory drugs, it makes sense to switch to another NSAID if the therapy is inadequate or if the side effects are too great. If monotherapy fails, it is common in veterinary medicine to combine two or more differently acting substances (opioids, glucocorticoids, NSAIDs, pyrazone derivatives such as metamizole or phenylbutazone) in order to potentiate the effects and thus reduce the dose and the potential for side effects of the individual preparation. Metamizole is suitable e.g. B. in many cases very good as a supplement to a non-steroidal anti-inflammatory drug, if its effect alone is not sufficient. The fixed combination of phenylbutazone and prednisolone is approved as a veterinary medicinal product and is also practically relevant for particularly severe cases. On the other hand, there is an absolute contraindication for the simultaneous administration of NSAIDs and glucocorticoids, since it can lead to severe gastrointestinal side effects. Tables 1 and 2 show a selection of non-opioid analgesics approved and suitable for dogs and cats, respectively. The administration of human anti-inflammatory drugs should be avoided in self-medication because of the high rate of side effects. For example cause Diclofenac and Ibuprofen in dogs, even in sub-therapeutic doses, classic side effects in the gastrointestinal tract with sometimes massive bleeding and are therefore not suitable for use.Paracetamol is in the dog only briefly and insufficiently effective and even in small doses liver damaging in cats it may because of the risk of intoxication never be used. Non-steroidal anti-inflammatory drugs are mainly excreted as glucuronide conjugates. Because of the reduced activity of their glucuronyltransferase, cats are even more sensitive to non-steroidal anti-inflammatory drugs than dogs and should only be treated with preparations approved for them. Metamizole is well tolerated by cats. However, since the metamizole injection preparations approved in Germany for horses, cattle, pigs and dogs contain benzyl alcohol as a preservative, they must not be used on cats. The z. B. Preparations approved in Switzerland with the addition of Aqua ad injectabilia are well suited for cats, as are the metamizole preparations from human medicine.

Tab. 1: Non-opioid analgesics approved for dogs. All listed preparations require a prescription.

Dosage and Art
the application
4.0 mg / kg i.v., s.c., p.o.
  • for perioperative pain
  • for inflammation and pain in acute and chronic diseases of the musculoskeletal system
  • the indicated dosage should not be increased
0.3 to 1.0 mg / kg i.v., i.m., s.c., p.o.
  • maximum use 3 days
  • frequent gastrointestinal side effects
  • in inflammation and pain in connection with degenerative joint diseases
  • Administer once a month together with the main diet
0.1 mg / kg s.c., p.o. (on the first day 0.2 mg / kg)
  • based on clinical response, the lowest effective dose may be used for long-term treatment
Novaminsulfone® ad us. vet.
20 to 50 mg / kg slowly
i.v., i.m., s.c., p.o.
  • for perioperative pain
  • for abdominal pain and diseases of the muscles and joints
  • good visceral and somatic analgesia
  • can be combined with NSAIDs if their effect alone is not enough
  • a human preparation must be rededicated for oral use
Phenylbutazone 20%® / -Gel PH®
10 to 20 mg / kg IV, IM,
s.c., p.o.
  • Check blood count if used for more than 7 days
(in combination with prednisolone)
(Prednisolone 0.1 to
0.2 mg / kg)
  • maximum use 7 days
  • Check the liver values ​​for long-term therapy about every 3 months
see carprofen, not for perioperative pain
  • additional inhibition of lipoxygenase (limited to a few hours after application)
4.0 mg / kg i.m., s.c., p.o.
  • in acute attacks in chronic diseases of the musculoskeletal system
  • maximum use 3 days
Source: Veterinary Pain Therapy Initiative ITIS. Recommendations for pain therapy in small animals (as of October 2010)
www.vetpharm.uzh.ch

A specialty among the NSAIDs is mavacoxib, which is approved orally for once-monthly use in dogs for inflammation and pain in connection with degenerative joint diseases. This is particularly useful if the dog has to receive painkillers regularly and permanently and the reliable daily administration of a preparation cannot be guaranteed. With any long-term use of NSAIDs, possible gastrointestinal and renal side effects should be considered and the laboratory values ​​checked regularly (approximately every three to six months).

Tab. 2: Approved or suitable non-opioid analgesics for cats. All listed preparations require a prescription.

Dosage and Art
the application
  • for perioperative pain
  • for mild to moderate pain
  • Approved for single use only
0.05 mg / kg p.o. (on the first day 0.1 mg / kg)
  • for perioperative pain
  • for inflammation and pain in chronic diseases of the musculoskeletal system
  • based on clinical response, the lowest effective dose may be used for long-term treatment
Novalgin®
(Human preparation)
20 to 30 mg / kg slowly i.v., i.m., s.c., p.o., rectal
  • for perioperative pain
  • for abdominal pain and diseases of the muscles and joints
  • good visceral and somatic analgesia
  • can be combined with NSAIDs if their effect alone is not enough
  • only use preparations without benzyl alcohol for injection, e.g. B. Minalgin® ad us. vet. (approved in Switzerland)
  • for pain and inflammation of the muscles and joints and after soft tissue operations
  • maximum use 6 days
  • in acute attacks in chronic diseases of the musculoskeletal system
  • maximum use 3 days
  • for symptomatic lowering of fever
  • in cats only approved as an antipyretic

Source: Veterinary Pain Therapy Initiative ITIS. Recommendations for pain therapy in small animals (as of October 2010)
www.vetpharm.uzh.ch



The available preparations for pain therapy are not approved for pets and birds, but have empirically proven to be effective (Tab. 3). In the case of small animals weighing less than 1 kg, liquid oral preparations usually have to be diluted in order to ensure exact dosing. They should be given either directly into the mouth or via a special treat. In the case of a lump-sum administration via drink or feed, it is not possible to ensure that the calculated dose can be completely absorbed.

Table 3: Non-opioid analgesics suitable for pets (e.g. rabbits, guinea pigs, chinchillas, mice, hamsters, rats). All listed preparations require a prescription. They are not approved for these species and must be rededicated by the veterinarian.

Dosage and Art
the application
4.0 to 5.0 mg / kg s.c., p.o.
  • for perioperative pain
  • for moderate to severe pain
  • for pain of an inflammatory nature
0.2 (to 1.0) mg / kg s.c., p.o.
Novaminsulfone® ad us. vet.
Rabbits 20 to 50 mg / kg
i.v., i.m., s.c., p.o.
others 50 to 100 mg / kg p.o.
  • excellently tolerated
  • for perioperative pain after abdominal surgery
  • for abdominal pain and diseases of the muscles and joints
  • good spasmolysis
  • a human preparation must be rededicated for oral use
Source: Veterinary Pain Therapy Initiative ITIS. Recommendations for pain therapy in small animals (as of October 2010)
Gabriel, S. Pain Therapy in Pets. In: Compendium Small Animal 2010.
www.vetpharm.uzh.ch

Multimodal pain management

Multimodal pain therapy is understood to mean "both the combination of painkillers with different mechanisms of action and the simultaneous, coordinated treatment of a clinical picture with different therapy methods" [2].

Comprehensive therapy for chronic pain patients includes the use of painkillers, regular weight control, physiotherapeutic and physical measures to build muscle and maintain mobility, possibly acupuncture, as well as the use of supplementary feeds such as B. Chondroprotectives. Surgical measures can also be important.

Pentosan polysulphate (PPS) has an anti-inflammatory effect, increases the proteoglycan content in hyaline cartilage, inhibits the enzymes that break down cartilage and improves the perfusion of the joints and the viscosity of the synovia. It is administered subcutaneously at a dosage of 3.0 mg / kg body weight four times with an interval of seven days.

Suitable supplementary feeds or complete dietetic feeds contain z. B. Glucosaminoglycans, hyaluronic acid, chondroitin sulfate, extracts of the New Zealand green-lipped farmed mussel, vitamin C and manganese and are supposed to positively influence the growth and building processes in the hyaline cartilage and support the physiological bone structure. Long-chain, polyunsaturated fatty acids have an anti-inflammatory effect and can also be used. Traumeel is also used as a homeopathic treatment® or Zeel® into consideration.

Careful weight reduction is indicated in overweight dogs and cats with chronic degenerative joint diseases. Every gram less body weight can have a positive effect. A "senior feed" or a special diet feed is suitable for this, which is low in energy but with z. B. the above-mentioned chondroprotective agents is enriched. In addition, the animal should "work out" the food. For this purpose, food balls are suitable, which the animal has to roll so that individual chunks of food fall out. Alternatively you can hide chunks of dry food in the apartment (or for the dog in the garden) or throw individual chunks that the animal then has to "chase" after.

If the animal is no longer as mobile due to its illness and its cleaning behavior is restricted, the pet owner should support the body care with a cleaning glove or a very soft brush. It also makes sense to make cats' favorite places more accessible, e.g. B. to put a chair in front of the windowsill or to build more floors in the scratching post.

A factor that should not be underestimated in the supportive therapy of chronic pain are physiotherapeutic and physical measures that strengthen the muscles and restore or maintain mobility. The use of an underwater treadmill (e.g. with an animal physiotherapist) works in some cases "real miracles", but simple physiotherapeutic exercises can also be carried out very effectively at home under the guidance of a veterinarian. Massage and thermotherapy (cold or heat, depending on the indication) can also be used specifically by the pet owner. Laser, radiation, magnetic field or shock wave therapy are possible as additional physical therapies. There are many ways to help Karlo, Harry and Klopfer. The prerequisite is the attentive observation by the animal owner, who should also question a changed behavior of his animal with regard to possible pain.


Source and further internet links

[1] Gabriel, S. Pet pain therapy. In: Compendium Small Animal 2010 [2] Initiative for veterinary pain therapy ITIS. Recommendations for pain management in small animals. October 2010 [3] Cat Movement. Information brochure Boehringer Ingelheim Vetmedica GmbH [4] Tacke, S. et al. Pain detection and management in dogs, cats and pets. In: Fachpraxis Nr. 51, June 2007 [5] www.tiergesundheit.com/hund/ache/ index.htm
Address of the author: Veterinarian Sabine Wanderburg, Seeweg 5 a, 23701 Süsel



DAZ 2011, No. 17, p. 66