The role of the veterinary nurse in homecare for the cardiac patient

Cardiac disease is common in small animals. Cardiomyopathies in cats are the most common form of heart disease, with a reported prevalence of around 15% of the feline population affected (Payne et al, 2015) and cardiovascular disease among the top ten causes of death in cats (O'Neill et al, 2015). It is estimated that 10% of all dogs presented to primary care veterinary practice have heart disease, with degenerative valve disease representing approximately 75% of these cases (Keene et al, 2019). The most frequent causes of canine death identified among UK purebred dogs were cancer, ‘old age’ and cardiac disease (Adams et al, 2010).

With the majority of cardiac disease being degenerative in nature, patients are likely to deteriorate gradually as their disease progresses and are at risk of developing life-limiting sequelae including congestive heart failure, arrhythmias, and aortic thromboembolism. At all stages, patients can be managed at home with regular rechecks, a suitably tailored home care plan and good communication with the veterinary team.

Identifying cases

Home care for patients with cardiac disease which is life-limiting is palliative by nature. Palliative care can be defined as relieving or soothing the symptoms of a disease or disorder at any stage of an illness (Shanan et al, 2020). Patients with incurable, advanced disease are obvious candidates for home care support; however, patients who have signs of cardiac remodelling, who are at higher risk of developing heart failure, are also candidates for home care, particularly those with owners wishing to do everything possible to support their pets. A recent survey by the Blue Cross (2022) found that 95% of pet owners said that their pet was part of the family, emphasising the bond that many clients have with their animals. Palliative care has been established in human medicine since the 1970s, but is a relatively new concept in veterinary medicine, with the animal hospice movement becoming established in America in the 1990s. While this is still a growing field in UK veterinary medicine, increasing numbers of practices now offer palliative care, with some offering purely home-based hospice and palliative care services.

Initial assessment and homecare plans

Individual patient assessment allows for homecare plans to be tailored to the patient. It is important that each patient is assessed individually to determine the patient's current stage in their disease, quality of life and individual needs. This provides a baseline which future assessments can be compared to. It is also important to remember that we are caring for people as well as their pets, and as such it is essential that we evaluate the client's needs, beliefs, and goals for their pet (Shearer, 2011).

Owner assessment

When assessing owners' expectations and goals, it is important that the owner has a clear understanding of the patient's disease process, its likely trajectory and ultimately what to expect at the patient's end of life.

In human medicine, three disease trajectories have been described for people with progressive chronic illness (Murray et al, 2005) (Figure 1) and these are easily transferable to veterinary medicine.

Cardiac disease has specific clinical signs which owners should be trained to look for. Learning how to monitor parameters accurately, particularly respiratory rate and effort, can allow for early changes to be noted and reported to the veterinary team for any appropriate changes to be made prior to further deterioration.

Open and honest discussions should be undertaken with owners about which trajectory is applicable to their pet and how their pet's disease is likely to develop, what signs or symptoms owners should look for and what interventions or treatment options the owner may be willing to pursue. The owner's ability to cope with the time, emotional, physical, and financial burdens of providing care are also important factors (Gardner, 2023).

Patient assessment

Providing an uninterrupted, quiet consultation time in which to perform the initial assessment of the patient allows for a full and detailed understanding of the patient's current health and an opportunity to identify areas which can be improved.

General condition

Patient weight, body condition score and muscle condition score should be checked at every assessment. Several factors can result in changes to weight in cardiac patients, including weight gain due to fluid retention (ascites, pleural effusion, oedema) or weight loss associated with anorexia or cardiac cachexia – a loss of lean muscle mass common in end stage cardiac patients (Figure 2). By noting changes promptly, the cause can be determined, and measures put into place to rectify problems, either through alterations in medication by the veterinary surgeon (additional diuresis, alterations to dose, changes of medication) or through nutritional plans implemented by the veterinary nurse. While gold standard care includes monitoring of renal parameters and electrolytes for patients receiving diuresis at rechecks or following alterations of doses, this should be reviewed on a case by case basis, particularly if the patient is clinically well and tests are likely to increase patient stress.

Owners can monitor the weight of small dogs and cats at home using baby scales, or even regular bathroom scales (holding the pet and deducting their own weight can be an easy way of doing this). Larger dogs can be monitored by using the scales at their local practice. The same method should be used consistently in order to provide an accurate means of monitoring, and owners may wish to calibrate home scales to match weights in practice in order to have comparable results both at home and at follow up visits. For patients with ascites, fluid accumulation will increase body weight, with noticeable abdominal distension visible. Owners can monitor changes to abdominal size at home using a tape measure around the widest part of the abdomen, taking care to try and measure consistently in the same place each time.

Nutrition

Not all cardiac patients have the same nutritional requirements and a ‘one size fits all’ approach to nutrition is not appropriate. Patient condition, diagnosis, other systemic illness and any electrolyte imbalance should all be taken into consideration.

Resting energy requirement (RER), can be calculated by multiplying body weight in kilograms to the power of 0.75 multiplied by 70 (Figures 3 and 4): e.g. (28 kg (0.75)) x 70 = 852 (Lumbis, 2014). Maintenance energy requirement can then be calculated by multiplying the resting energy requirement by known life stage factors (Table 1). These calculations provide a starting point but may need to be reassessed over time.

Table 1.

Known life stages and corresponding factors used to estimate daily energy needs for dogs (Ohio State University, 2023)

Important questions to ask owners when discussing nutrition include:

• What diet is the pet currently fed?
• How much food do they have a day?
• Does the pet have any particular dietary requirements? e.g. hypoallergenic diets, allergies, low fat diet due to history of pancreatitis
• Do they eat well by themselves, or do they need to be tempted?
• Do they have any extras/treats?
• What is their favourite food?

These facts alongside the initial assessment of general condition can help to determine whether the patient is on the most appropriate diet or whether changes would be beneficial.

A good quality diet should be fed, without protein restriction (unless concurrent renal disease is present). Sodium restriction is only advised in later stages of cardiac disease, and although several specialist low sodium cardiac diets are available on the market, these are often not especially palatable and are therefore not commonly suggested by cardiologists, as the necessity for the patient to eat is greater than the requirement for sodium restriction.

Patients with a low body condition score will require additional calories. Weight loss can be due to anorexia, which is a common issue for cardiac patients. Tempting to eat by hand feeding, warming foods or offering strong smelling foods may be necessary. In cases where tempting to eat isn't successful, pharmacological intervention may be necessary. In some cases, anorexia is related to electrolyte disturbances, particularly hypokalaemia in patients receiving diuresis, and blood sampling to monitor electrolytes is indicated in these patients to determine whether supplementation is appropriate. In patients who may be experiencing pain, for example cats recovering from aortic thromboembolism or patients with neoplasia, pain scoring may be beneficial to ensure that the patient is pain free and that this is not the underlying cause for anorexia.

Obese patients will require less calories, and weight loss in these patients will often improve cardiac output, exercise tolerance, and breathing rate and effort, therefore improving quality of life. For patients that have already progressed into heart failure, there are studies which suggest that obesity can be associated with longer survival times (the obesity paradox). The reasons for this are unclear, but possibilities include obese patients presenting earlier for treatment due to more pronounced clinical signs, or excess body fat providing a ‘buffer’ against weight loss associated with cachexia.

Patients with low muscle condition scores due to cardiac cachexia may benefit from the addition of omega 3 fatty acids in the form of fish oils, which can be purchased readily in health food shops and online. Inflammatory cytokines, especially tumour necrosis factor (TNF) and interleukin (IL-1), are primary mediators of cachexia as they inhibit appetite, increase energy metabolism, and accelerate the breakdown of muscle protein (catabolism) of lean body mass (Freeman, 2010). Omega 3 fatty acids have been shown to reduce these inflammatory cytokines: 40 mg/kg/day eicosapentaenoic acid (EPA) and 25 mg/kg/day docosahexaenoic acid (DHA) were shown to alter plasma fatty acids and improved cachexia score in dogs (Freeman et al, 2006). Sourcing a good quality supplement from a reputable supplier which has quality assurance (ideally International Fish Oil Standard certified) is important to ensure guaranteed ingredients and quality. Cod liver oil is not recommended as it contains high levels of vitamin D and A, which may result in toxicity if given at the doses required to meet the requirement for EPA/DHA dosage. Flaxseed oil is also unsuitable as it is not effective at providing omega 3 in dogs and cats.

In humans, bleeding times were greatly increased when omega 3 and aspirin were administered together and it is thought that clopidogrel is likely to interact in a similar manner (Lenox and Bauer, 2013), therefore care should be taken when administering omega 3 to patients who have been prescribed anti-clotting medication due to the increased risk of delayed clotting.

Exercise

For patients who do not have current signs of heart failure, regular gentle exercise is beneficial. Many patients will self-limit the amount of exercise they are able to tolerate, sitting or turning for home once they have done enough, and owners should be educated to look for these cues and respect them. For patients who do not self-limit, owners should take care not to allow their pet to do more than they can manage comfortably, monitoring their breathing, colour and time it takes for recovery after a walk as gauges of what is manageable. A harness may be more appropriate than a collar for walking dogs to avoid airway compromise in patients who may already have reduced capacity for oxygenation.

Aids such as pushchairs can be useful in later stages to allow for further mental stimulation once the patient has reached their physical limit (Figure 5).

For patients who are higher risk of syncopal episodes or sudden death, e.g. those with dilated cardiomyopathy or subaortic stenosis, consideration should be given as to where they can walk safely, especially with larger dogs who cannot be carried easily.

Physiotherapy can be beneficial for some patients. Effleurage and passive range of motion can help to provide patient relaxation (and improve patient/owner bond), improve blood flow and reduces pain (Cartlidge, 2014). This can be particularly useful for feline patients recovering from aortic thromboembolism with limb paralysis, although care should be taken not to do more than the patient is willing to tolerate comfortably.

Medication

It is important that owners understand what the medications their pets have been prescribed are for, how often they should be given and at what dosage. Providing this information in writing can be useful as this also provides a reference later outside of the veterinary clinic. If changes are made to doses, or further medications are added, then a new, dated medication sheet should be issued to keep information current.

For patients receiving multiple medications, clients may find it easier to prepare a week's medication using tablet organisers (Figure 6).

Potential side effects should be discussed (e.g. polyuria/polydipsia, possible breaking of house training and renal effects with diuresis; low blood pressure and associated symptoms of weakness with beta blockers) as well as how to best administer medication. Medicating cats in particular can be challenging, with one study finding that ‘a substantial number of owners indicated that it was “extremely difficult” to medicate their pet’ with the level of concern increasing as the number of medications and dosing frequency increased (Reynolds et al, 2010). Making owners aware of different formulations of medications, e.g. tablets, liquids, flavoured options, and tips on how to medicate other than manual oral administration can be especially important for improving quality of life for both patient and owner.

Quality of life assessment

Studies have shown that the majority of owners value quality of life over quantity, with 86% of dog owners (Oyama et al, 2008) and 93% of cat owners (Murray et al, 2005) willing to trade some amount of survival time for good quality of life, emphasising the importance of monitoring and maintaining this.

Several assessment tools are available to veterinary professionals which can be useful for monitoring patient progress.

The Functional EvaluaTion of Cardiac Health (FETCH) questionnaire was developed by the Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University specifically for dogs with cardiac disease (Freeman et al, 2005). It is designed to assess patient quality of life in the previous seven days, and so can be followed up with re-evaluation within this period. It focuses on cardiac specific symptoms, such as respiration, coughing, exercise tolerance, syncopal episodes, food intake, urination and general demeanour.

Another user-friendly quality of life scale which can be used to guide highly bonded owners who may be in denial about issues which may be affecting their pet is the HHHH-HMM (hurt, hunger, hydration, hygiene, happiness, mobility, and more good days than bad) scale (Villalobos, 2011), which was developed for oncology patients but can easily be adapted to cardiac patients. This assessment encourages open conversation with clients and suggests possible interventions or adaptations that can be made for the pet which can open up further discussions.

When questioned about their own concerns for their pets, many owners worry that they will not know when it is the right time to consider euthanasia or that their pet will suffer. As well as quality of life assessments performed in practice, there are tools available that owners may find useful for monitoring their pets at home either daily or weekly, ideally encouraging more than one family member to participate in order to provide a more accurate evaluation of the pet (Figure 7). Another simple method that owners can use at home is marking good days and bad on a calendar to assess the balance and identify any causes for bad days and improvements that may be able to be made on discussion with the veterinary team.

This home-based assessment allows owners to remain involved in their pet's care and the decision-making process, allowing them to have confidence that any choices made are the right thing for their pet.

Conclusions

Veterinary nurses are a tremendous, currently underused resource for the development of palliative care within the veterinary profession (Goldberg, 2016). Homecare based on proper assessments with regular follow ups (either remote or hands on), can make a huge difference to cardiac patients, by identifying factors which can be improved or altered in order to improve quality of life and patient outcomes. This process also allows us to form good relationships with our clients through open conversation. By providing them with the information and means to be more involved in their pet's care, and by offering support and advice during periods of deterioration, we can give families better end of life experiences with their pets.

KEY POINTS

• Cardiac disease is common in small animals and among the top causes of death in patients.
• The majority of owners value quality of life over quantity.
• Veterinary nurses can play a key role in improved homecare for cardiac patients by providing education and support to owners, allowing them to make informed decisions about their pets care and enabling them to monitor their pet for signs of deterioration.
• Patient assessment including condition scoring, nutritional assessment and quality of life assessment allow for tailored home care plans to be designed which can improve patient welfare and identify areas for improvement.