Caroline J. Hewson, MVB, PhD, MRCVS
This presentation reviews ten areas of veterinary patient care that may not be widely known (hence 'secrets') and that can tend to be overlooked in the busyness of the clinical day.
# 1 & # 2 Hospitalisation of Cats
When cats are hospitalised, they are typically put in a cage containing a litter tray, food and water as appropriate, newspaper on the floor +/- soft bedding. For cats surrendered to shelters, such unenriched housing, coupled with the unpredictable and uncontrollable nature of their situation, can cause significant distress. In one study that expressly examined the question, cats relinquished by their owners showed higher levels of stress than stray cats (Dybdall, et al., 2007).
One of the many things that can help minimise stress in caged cats is to provide them with some environmental control. In a recent randomised, controlled study that compared enriched and traditional housing for newly arrived shelter cats (Gourkow and Fraser, 2006), cats in the traditional cage were significantly more stressed at the outset and took an average of eight days to approach the lower stress level of the cats in the enriched housing, who had access to toys, a hiding place and consistent human interaction. The strength of evidence is limited by the fact that the study was not blinded, although blinding would have been difficult to achieve. However, the data are consistent with a secondary finding of the study that whereas 26% (8/31) of cats in the traditional housing were sent to isolation because of illnesses (undescribed), only 12% (4/34) of cats in the enriched housing succumbed. This secondary finding is consistent with findings elsewhere that persistent stress can adversely affect health and immunity (e.g., Connor, et al., 1998; Moberg, 2000).
These data indicate that we can make our care of feline patients even better by recognising that stress is caused by separation from the owner (Dybdall, et al 2007) (see Lecture 3), and by providing hospitalised patients with some environmental control such as a way to hide themselves (e.g., towel over half of the cage door) and toys (Gourkow and Fraser, 2006).
#3 Cat Litter Tray Size
Recent research on 74 cats from 45 households indicated a statistically and clinically significant preference for using a larger litter box, especially if it was in a preferred location (Guy and Hopson, 2006). The larger box was almost twice as long as the standard size and, in 41 of the 45 households, there were significantly more deposits of faeces and of urine in the larger box. These data suggest that many cats may prefer a larger litter box, and that providing a larger one in a preferred location may be an important additional tool in the management of cats with inappropriate elimination.
#4 & #5 Hospitalisation of Dogs
A popular assumption is that hearing the radio is a comfort to in-patients. Often, local radio is played, typically featuring a combination of high-energy speech and pop music. In a randomised, controlled study of shelter dogs in the UK (Wells, et al., 2002), there was no detectable effect of human conversation (radio) or pop music on dogs' behaviour. However, the dogs spent significantly less time barking, and more time resting, with classical music. In the absence of other scientific data, this study suggests that we can make our care of canine patients even better by playing (melodious) classical music in the kennel area.
# 6 Tail Docking in Puppies
Puppies typically have their tails docked without analgesia being provided; in Canada, 83% of veterinarians performing the surgery in 2001 were estimated to have done so without using analgesia (Hewson, et al., 2006). Pertinent data on the likely effect of this come from rats and human infants. In summary: neonatal rat pups were injected with substances that were either chronically irritant (Complete Freund's Adjuvant (CFA)) or temporarily irritant (carrageenan). Injections were given in one paw, without analgesia. The sensitivities of both the injected paw and the contralateral one, to mechanical pressure and to heat, were then assessed at various intervals afterwards, and under various conditions. The data indicated that:
Pups that were allowed to suckle during exposure of the inflamed paw to pressure or heat could tolerate a higher intensity of these (Anseloni, et al., 2002, 2005) than injected pups that did not suckle. The sucrose component of the milk, specifically, and the mechanical act of sucking provided the analgesia. The sucrose component was opioid-dependent (Anseloni, et al., 2002, 2005) but did not develop until ~4 days after birth.
Reinjection of the paw, without analgesia, at 62 days old, resulted in hyperalgesia to mechanical and thermal stimuli, as compared to rats that had not their paws injected as pups (Ren, et al., 2004).
Similarly, human infants circumcised without analgesia at 5 days of age or younger showed an exaggerated pain response to routine vaccination at 6 months (Taddio, et al., 1997). Likewise, neonatal babies that were blood sampled by heel-lancing, without analgesia, and subsequently sampled by venipuncture showed increased sensitivity to venipuncture as compared to infants who were given local anesthetic cream before heel-lancing (Taddio, et al., 2002).
Taildocking is more invasive than carrageenan or CFA injections, circumcision or heel lancing. In addition, canine puppies may be said to be intermediate in development between rat pups and human infants (Clancy, et al., 2007). Thus, if the research in rats is paralleled by findings in human infants, it is not unreasonable to extrapolate the results to canine puppies. Under that assumption, and in light of the difficulty of providing the multimodal analgesia that amputation requires, we can improve our care of puppies by not docking their tails.
# 7 & # 8 Bedding Depth and Cage Size for Golden (Syrian) Hamsters Mesocricetus auratus
In the wild, golden hamsters burrow 60 to 80 cm beneath the ground and from there have tunnels of a further ~60 cm leading to resting and food storage areas (Sorensen et al., 2005). However, the usual hamster cages are too small--typically 24 cm H x 35cm L x 25 cm W--to permit the animals to burrow. Recent randomised controlled studies of laboratory hamsters indicated that:
When given bedding of 40 cm or 80 cm deep, hamsters burrowed and dug tunnels to create sleeping chambers (Hauzenberger, et al., 2006). They also showed significantly less bar-biting, which is notable because the behaviour is considered to indicate present or past environmental inadequacy.
When given cages of 10,000 cm2 (105 cm L × 95 cm W × 45 cm H), with 15 cm of bedding, hamsters showed less bar-biting (Fischer, et al 2007) compared to those in cages of 1,800 cm2 (32 cm L × 57 W × 45 cm H) that had the same bedding depth. The authors noted that the large cage size nevertheless only represented 0.007% of the normal size of hamsters' territory in the wild.
These studies indicate that we can make our care of hamsters even better by advising owners to provide at least 40cm of bedding, and/or a cage area of at least 10,000 cm2.
# 9 Use of Analgesics for Routine Surgery
Canadian research on the use of analgesics in small animal surgery in 1994 (Dohoo and Dohoo, 1996) and 2001 (Hewson, et al., 2006) showed growing awareness of and use of analgesia, coincident with more drugs being available. However, there were still inadequacies e.g., in 2001, between 22,414 and 35,137 dogs a month, nationally, were estimated to have been spayed using pre-incisional analgesia only, most commonly butorphanol or meperidine alone. These data emphasise that good patient care requires an up-to-date policy on analgesia. They also illustrate the scale on which animals may be affected by inadequate usage of pain relief.
#10 Thoroughly Assess How Patient-Friendly Your Clinic or Hospital Is
Without a critique of clinic facilities from an animal's point of view, it can be very easy for the practice team to cause or exacerbate distress in patients without realising it. However, as the scientific examples above illustrate, good patient care can be made even better by a detailed review of patient care practices, from the patient's point of view. An excellent starting point is the Feline Advisory Bureau's Cat Friendly Practice booklets (Feline Advisory Bureau 2007), which pull together a lot of information. For a systematic evaluation that includes other species, I have developed an online assessment, which generates a score and ranking relative to other practices, and has an accompanying manual that describes simple ways to improve areas of weakness (information available on request, or from firstname.lastname@example.org).
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