Principles of barrier nursing in the veterinary hospital

Barrier nursing is a term used to describe the care of patients with infectious diseases (Guthrie and Lane, 2006). Specific protocols are put in place to ensure there is minimal risk of cross contamination between patients and the person responsible for their care. The patients are usually isolated from the main hospital area and excellent hygiene and disinfection protocols are followed.

It can be easy in everyday practice to become blasé about nursing patients in isolation. The extra care and precautions can be time consuming and in a busy practice, this can lead to the cutting of corners. However this can have catastrophic consequences for the welfare of other patients in the hospital, the welfare of other animals in the community, and in some cases human health and wellbeing can also suffer.

Veterinary nurses need to understand the importance of maintaining standards set out by barrier nursing protocols, how to provide holistic care to patients in isolation, as well as how to keep themselves and other patients safe. It is vital that good barrier nursing protocols are in place to prevent a potential crisis from occurring.

Conditions that require barrier nursing

Animals that need barrier nursing can range from a kitten with ringworm to a dog with meticillin-resistant Staphylococcus aureus (MRSA). The nursing of a kitten with ringworm may be as simple as housing it away from other patients, wearing the appropriate protective clothing and ensuring good hygiene and disinfection protocols are followed; whereas nursing a patient with MRSA will involve strict adherence to isolation and full barrier nursing precautions, including full protective clothing and the disposal of all bedding and equipment used to treat that patient. Table 1 lists the most common conditions seen in practice that require barrier nursing (Guthrie and Lane, 2006). Of these conditions some patients (i.e. those with feline upper respiratory tract disease, kennel cough, ringworm, salmonella and campylobacter) may not be nursed in the hospital environment, but sent home with the owner, depending on the severity of the illness. Strict instructions should be given to owners on keeping themselves as well as their own and other animals safe. All the other condition require full barrier nursing precautions.

Routes of infection within the hospital environment

Infection may be passed between animals within the veterinary hospital in any number of ways (Table 2) but they will all involve contact with infectious body fluids such as faeces, blood, pus, vomit, saliva, urine, ocular, nasal and vaginal discharge and wound exudates (Aspinall, 2006). Some ectoparasites are highly contagious such as Sarcoptes scabiei and although these animals may not be hospitalized great care must be taken with any bedding or clothing they come into contact with in the hospital.

Disease transmission can occur either through direct or indirect contact (Aspinall, 2006) (Table 3). For transmission through direct contact the animals need to physically have contact with one another. The infected animal needs to have the micro-organism living in or on them in order for the micro-organism to survive. Indirect contact requires no physical contact between animals in order for transmission to occur; instead it is contracted by inanimate objects, the environment or ectoparasites coming into contact with an animal.

Siegal et al (2007) have shown that contaminated hands are a common denominator in indirect contact transmission if correct hand hygiene is not used between patients. This could be from either another patient or from touching a contaminated object. Objects such as thermometers, pens and stethoscopes may transmit pathogens if they are not cleaned between patients. Contaminated food and food bowls, water, bedding and medications such as intravenous fluids can also be an environmental source of infection. As indirect contact involves the transfer of a pathogen through another animal or a contaminated intermediate object, the environment is very important when it comes to preventing the spread of infection.

Physically separating infectious animals by placing them in isolation should reduce the risk of disease exposure to healthy animals and prevent healthy patients acquiring a nosocomial infection. They are unable to directly or indirectly infect other animals as long as appropriate barrier nursing techniques are strictly adhered to.

The isolation area

As shown by Cooper and Lane (1999) and Jones and Mullineaux (2007) the design of the isolation facility should take into account the following factors:

• The kennels should be apart from the main hospital area. For dogs this means at least 5 m. This takes into account the distance a dog sneeze can travel. For cats a minimum of 3 m separation from the cat housing area is appropriate
• Ideally it would have its own separate entrance and exit away from the main hospital area. This would reduce the risk of contamination to other hospitalized patients, and patients with suspected infectious disease can bypass the hospital area and be admitted straight into isolation
• It needs to have an effective ventilation system directed away from the main hospital area for the risk reduction of airborne disease. This is particularly important if there is more than one patient housed in isolation at a time
• There should be a heating and cooling system in place as well as good lighting. Adequate humidity and temperature can be an important part of the patient's recovery
• The surfaces and floor should be designed to be cleaned easily
• Wall-mounted hand sanitizer units should be placed outside but next to the door to the unit. They should be used each time a person enters and exits the isolation unit
• Sneeze barriers should be present between cages to prevent cross-contamination
• The doors should be locked easily and the keys stored within easy reach. This is to prevent animals escaping but also to prevent lay staff and clients accidentally entering the isolation area. If families want to visit they need to follow the appropriate guidelines and wear protective clothing. They must enter and exit without walking through the hospital
• There needs to be adequate storage for food and water bowls, food bins, waste disposal, disinfectants, paper towels, newspapers and bedding as well as bandaging materials, needles and syringes, scissors, intravenous fluids, and any other medical supplies that may be needed by infectious patients
• An area should be set up for a foot bath as well as a sink with a hot and cold water supply for hand and bowl washing. This would also provide a fresh water supply for the patients
• The sink should be a clinical non hand-operated hand basin
• A good pest control system to prevent vermin and for the control of flies, ants, lice and fleas
• A storage area for all disposable clothing and equipment needed for the nursing of the contagious patient
• A disposable paper towel unit for drying hands and cleaning will help to reduce the risk of infection.

The housing of infectious animals is an important part of the treatment and recovery process as well as minimizing the risk to other healthy animals. Figure 1 shows a cat in isolation — note the cage is fully enclosed, and there are no open bars allowing aersosol contact with the cat in the cage next door. The isolation area should be regularly inspected for stock levels and cleanliness, and kept manintained and ready for use at any time.

Infection control procedures

The hospital should have standard operating procedures (SOPs) in place to ensure the safety of personnel. It needs to be comprehensive and all personnel should be up to date with the procedures. Proper adherence to SOPs has been shown to decrease the transmission of infections. It should cover the following points listed in Table 4.

Hand hygiene is one of the most important factors in reducing the transmission of infectious agents as cited by Siegal et al (2007) and it is essential it is part of the SOPs. The term ‘hand hygiene’ includes the use of both plain or anti-septic soap and water and also the use of alcohol-based foams and gels that do not need rinsing. If the hands are visibly unsoiled alcohol-based products are preferable to soap and water. Holston Moore and Rudd (2008) and Siegal et al (2007) recommend that hand hygiene should be performed:

• Before and after attending to a patient
• After contact with wounds, soiled dressings, blood, mucous, pus or other body fluid, faecal and urine contamination
• After taking a patient's pulse, lifting or moving a patient or other procedure
• Before and after examining wounds, drains or catheters
• Between touching contaminated and non-contaminated parts of the patient's body
• After contact with stethoscopes, thermometers and other inanimate objects in the immediate surroundings of the patient
• After removing gloves
• When leaving the isolation area.

Ideally only one nurse would be allocated to the care of infectious patients each day and only fully-trained staff should be working in the isolation area. They would have no contact at all with the other animals in the clinic although in everyday practice this is often not achievable due to staffing levels and commitment. Regardless of the setup of the hospital and isolation unit certain protective clothing should always be worn in the nursing of these patients (Figure 2):

• Disposable gown or overalls. These need to fully cover the nurse from the neck down to their feet and should be long sleeved
• Gloves – these must be changed after touching contaminated objects and before touching patients
• Disposable shoe covers or similar
• Plastic apron
• Mask and goggles. Particularly important if dealing with airborne zoonoses, but also for protection in the use of vaporized disinfectant sprays
• A hair covering. Ringworm spores, some ectoparasites and vaporized body fluids can leave deposits in the hair and lead to the possibility of cross contamination.

The protective clothing should be used in such a way that when putting on and taking off they do not contaminate the normal clothing of the nurse. They should only be worn in the isolation area and not into other areas of the hospital, and should be disposed of once removed. If items of clothing are worn that are not disposable and are not heavily soiled they may be soaked in the appropriate diluted disinfectant solution, e.g. TriGene, and then washed and dried separately. However any heavily soiled personal protective clothing, and all items worn when nursing a patient with an illness such as a MRSA infection, should be disposed of in the biological waste bag and held separately while awaiting collection.

Adequate supplies and equipment should always be available in the isolation unit. There should be a comprehensive list of these and the unit should be re-stocked regularly. They include such items as needles, syringes, food, intravenous fluid bags, catheters, and tape among other items used. Pens should not be taken into the isolation unit and then taken out again. There should be a supply of pens available in the unit that must be wiped clean with a suitable disinfectant between use and when finished.

As shown by Aspinall (2006) personal hygiene is essential. Nurses should remove watches, necklaces, rings and other jewellery that could come into contact with an infectious patient before starting their rounds. Any wounds, scratches or areas of open skin on the hands and arms of the nurse need to be covered with a waterproof occlusive dressing. These should be replaced regularly. If the nurse is suffering from multiple or chronic skin lesions on their hands and forearms it may be better for another nurse to deal with the infectious patient.

If a nurse suspects she has been exposed to a zoonosis (e.g. leptospirosis, ringworm, campylobacter, salmonellosis) medical advice should be sought.

Nursing the infectious patient

Along with wearing the protective clothing mentioned above there are many basic nursing protocols that should be followed in the nursing of the patient in isolation. These will further help prevent cross contamination between patients and protect the health and safety of the nurse in the presence of zoonoses. A high standard of aseptic technique should always be used when dealing with these patients. The key elements are shown in Table 5 and covered in more depth below.

The nurse should always care for the least serious patient first. Once they have been seen the nurse can then move on to the next patient, with the most seriously infectious patient being seen last. This will help prevent the spread of illness to patients who are already compromised and suffer with lowered immunity. Every effort should be made to ensure that the patients do not lick the face and arms of the nurse who is caring for them.

The hands and forearms (if wearing short sleeve gowns) should be washed with an antiseptic soap and water before and after handling each patient. An instant hand sanitizer should also be used between patients. Gloves should never be solely relied on to prevent the transmission of disease. If the gloves become contaminated, punctured or torn while dealing with a patient they should be replaced as soon as possible. The gloves and aprons should always be changed between patients and before touching anything else.

While cleaning each cage and patient ensure that the patient has no contact with other patients in isolation. They need to be confined to their cage area and under no circumstances should they be allowed out to roam around. Ideally they would also remain in the same cage for the duration of their stay. If possible, use the same bowls and litter trays for each patient, and these should be cleaned and disinfected between each use. The cages should be cleaned at least once a day however in some cases this may need to be more frequent, i.e. in a patient with parvovirus. Ensure that clean bedding does not come into contact with any animals before use; it should be stored separately away from the cages and waste bins.

Footbaths should be prepared at the entrance and exit of the isolation unit and must be used each time someone enters and exits the unit. It should be prepared with an appropriate disinfectant that has a broad spectrum activity and is effective on fungal, viral and bacterial contamination, such as TriGene Advance. A dilution of 1:100 is most effective in high risk situations.

The appropriate diet should be fed to each patient taking into account their individual needs, i.e. pediatric, gastrointestinal or geriatric. In some cases an animal may be nil per os. The food requirement should be calculated to meet the patient's resting and maintenance energy requirements as well as their water requirement. The food preparation area must be well away from the waste bins and the cages.

If a nurse is pregnant or suspects that she is pregnant she should take special care when handling patients in isolation, particularly in the instance of zoonoses. If possible, other nurses should deal with infectious patients and the pregnant nurse should be placed on other duties.

Finally it is essential that comprehensive hospitalization sheets are kept and filled out regularly. They need to include information on medications, demeanor, appetite, intravenous fluids, temperature, pulse, respiration as well as urination and faeces. Any changes or concerns should be brought to the veterinary surgeon's attention immediately.

Communication is a key element in the wellbeing of these patients; all staff should be kept up-to-date on each individual patient's progress. This includes reception staff who will be taking the phone calls from the worried owners.

Cleaning and disinfection

A rigorous disinfecting regimen should be employed for all cages and equipment that are used when caring for infectious patients. It is vital that the disinfectant used is effective against the organism in question. They need to be diluted to the correct strength according to the manufacturer's instructions and used appropriately to ensure the chemicals are safe and effective. Disinfectants that are too weak will not sufficiently kill all of the bacteria or viruses present. Too strong and they can be harmful to animals and veterinary professionals as well as not being cost effective. Suitable disinfectants that are effective against fungi, viruses and bacteria include Virkon and TriGene.

All cleaning materials should be kept in the isolation area or nearby and labeled For isolation use only. They should not be removed from the area and used in other areas of the hospital. The cages must be cleaned first and all organic waste must be removed from the cages before they are disinfected as some disinfectants are inactive against organic materials.

Any heavily soiled bedding, newspapers and other items used are disposed of in the clinical waste, usually a yellow bag with a biological hazard label (according to the relevant regulations) and stored until collection in a manner that will not contaminate other waste or equipment. The isolation unit should have a sharps bin where all sharps are placed; they are not to go in the general hospital sharps collection bins. Non-soiled bedding can be soaked in a suitable disinfectant according to the manufacturer's instructions and washed separately to other bedding.

Personal protective clothing should be worn when cleaning the unit. It is important that all surfaces are cleaned, not just the cages, in the isolation unit including the doors and door handles, drip stands, bench tops, cage doors and handles and other surfaces that are touched often. They should be cleaned and disinfected and left for the appropriate time (depending on the product used i.e. TriGene is usually 10 minutes in the presence of blood or a high organic load) before other animals are placed in the cages.

Psychological needs of the patient in isolation

It is important to remember that even though these patients must be kept in isolation that does not mean they should also be subject to complete sensory deprivation. A radio left on for company is a must. Boredom, loneliness and stress can all hinder recovery and it is important that some time is spent with these patients each day as long as the nursing protocols are observed. Figure 3 shows a litter of kittens all with upper respiratory disease. As they are from the same family and are receiving the same treatment they have been housed together.

The use of Feliway and Dog Appeasing Pheromone (DAP) diffusers should be encouraged. Feliway is a synthetic pheromone that mimics the cat's own facial pheromones which cats use to make them feel secure and safe in their environment. DAP is a similar product which can help dogs feel less anxious and fearful by producing a calming effect on the brain. Many animals react positively to these products. The spray should be used 20 minutes before an animal is placed in a cage; often this is not possible in the isolation unit. A plug in diffuser is an acceptable alternative to the sprays and may be preferable in an isolation area. Dry catnip can be sprinkled in cages and catnip spray can be used for those cats that enjoy them.

Ping pong balls are a cheap and easy way to provide entertainment for cats; they can either be disinfected or thrown away when the patient is discharged. Some cats enjoy playing with straws which can be disposed of once they become tatty.

For low risk and non-zoonotic conditions the owners should be encouraged to visit as long as they follow the procedures, understand the risks and wear the appropriate personal protective clothing. They should pre-arrange a time when they will be visiting and should be met by the nurse who will then take them into the unit. They should not be left unattended in the isolation unit at any time.

As with all hospitalized animals, regardless of where they are, time should be spent talking and interacting with them, this is particularly important with animals that are in isolation. Patients need to have some positive experiences, not just see veterinary nurses when invasive procedures need to be done, i.e. when giving medication.

Client communication

Ideally barrier nursing would begin when the client rings to make an appointment to visit the practice. If the symptoms are suggestive of an infectious disease, the client should be informed to keep the animal in the car and avoid contact with other animals and people in the waiting room. Common scenarios may include young unvaccinated dogs with vomiting and/or bloody diarrhoea, upper respiratory disease and seizures.

Clients should be phoned each day with an update on the patient's progress. As mentioned above, visits can be encouraged with low risk and non-zoonotic patients as long as the set precautions are followed.

In some instances when animals are discharged the owners need to be informed that their animal may still shed the microorganism into the environment for a period of time. They should avoid contact with other animals, public parks and pavements, and in the instance of zoonoses such as leptospirosis they should be informed of the hygiene issues relating to themselves.

Conclusion

Barrier nursing patients in isolation can offer many challenges to the veterinary nurses nurse designated to their care. It requires an excellent understanding of the infectious diseases present and how they can be transmitted from one patient to another and in some instances to people. The nurse needs to understand the process involved in how pathogens can transfer from one patient to another in order to keep other animals safe, both in the hospital and in the community.

Although time consuming and demanding, barrier nursing can greatly improve the patient's outcome and experience in the isolation unit.

Key Points

• Disease transmission can occur either through direct or indirect contact and it is important to have an understanding of these two routes in order to prevent the spread of infection.
• Hand hygiene is one of the most important factors in reducing the transmission of infectious agents.
• Personal protective clothing and personal hygiene are essential when it comes to nursing patients in isolation.
• A high standard of aseptic technique should always be used when dealing with patients.
• The psychological needs of patients in isolation should not be underestimated and time should be spent addressing this issue.