Blood transfusion
In addition to rehydration with crystalloid fluids , some feline flea-anaemic patients may require or benefit from a whole-blood transfusion . The decision as to whether a transfusion should be administered will be made by the VS , but it has previously been recommended in chronic anaemia where the PCV is < 10 % [ 6 ] . The goal of transfusion in cats is to increase the patient ' s PCV to 20 %, although in reality this level is not typically reached . Any improvement in PCV for the flea-anaemic patient is likely to have a positive impact on the patient ' s demeanour and can result in improved ability to eat and drink independently .
Despite the positive outcomes associated with blood transfusion in these patients , there are significant risks , which need to be considered . Unlike dogs , all cats have antibodies to non-self RBCs regardless of whether they have previously received a blood transfusion . This can result in life-threatening transfusion reactions if the wrong blood type is given . It is therefore essential that every cat is blood typed prior to transfusion and the correct donor blood is selected ( this is usually ‘ like for like ’ – i . e . type A cats should receive type A blood ). The VN will commonly monitor the blood transfusion in these patients by measuring and recording vital parameters ( heart rate , respiratory rate , blood pressure and temperature ) and should be aware of the signs of a transfusion reaction . These can include restlessness , vocalisation , tachypnoea , bradycardia , tachycardia , hypotension , hypertension and pyrexia . Unlike in dogs , urticaria is rarely seen in cats . If a transfusion reaction is suspected , the transfusion should be stopped immediately and a VS notified . Additionally , with every blood transfusion there is a risk of transfusiontransmissible infection ( TTI ). In cats , TTIs can include feline leukaemia virus ( FeLV ), feline immunodeficiency virus ( FIV ), feline coronavirus ( FCoV ), Anaplasma phagocytophilum , Ehrlichia species and Bartonella species [ 17 ] . It is therefore recommended that all donor cats undergo a vigorous screening process using sensitive tests to reduce the risk of TTI .
Given the risks and difficulties in obtaining blood from a feline donor , it is understandable that alternative options for blood transfusion in cats have been investigated . Previously , an artificial blood product ( Oxyglobin ) has been used off-licence but , at the time of writing , it is not available in the UK . Successful xenotransfusions of canine blood to feline patients without severe adverse reactions have been reported . However , a review of these cases concluded that antibodies to canine RBCs develop in 4 – 7 days , at which point the cells are destroyed by the cat [ 18 ] . Cats that received a second xenotransfusion after this time were likely to have a severe , often fatal , anaphylactic reaction . Therefore , where possible , a type-specific feline blood transfusion is preferred , as the reported 30-day RBC lifespan [ 19 ] for these transfusions is preferable to the available alternatives .
Temperature
The feline flea-anaemic patient is susceptible to hypothermia , due to impairment in their ability to thermoregulate . The reason for this inability is often multifactorial , with the relatively small size of the patient paired with the often poor body condition score being significant factors . Poor body condition means the patient has minimal to no fat reserves , which would ordinarily provide insulation , while the small size and large body surface area provides a relatively greater surface for heat loss , and this can be worsened by problems with fur loss . In addition to this , lack of energy reserves can mean the normal behaviour of shivering in response to hypothermia can be impaired .
To aid the patient , VNs should implement active warming in whatever format is available at the practice ( e . g . heat pads ), in addition to passive warming techniques such as supplying blankets . The patient ' s temperature should be monitored regularly until normothermia is established , at which point the frequency of monitoring can be decreased . Typically , once the patient ' s demeanour improves to the point where they are moving around by themselves , active warming is not needed but passive warming should remain in place . As with any patient , the option for the cat to choose to move away from the heat source must be available to prevent overheating .
Feeding
Meeting the nutritional needs of any inpatient is a core aim for the VNs responsible for their care . If the feline patient is eating independently , this can readily be achieved by selecting an appropriate diet and calculating the amount needed in accordance with the patient ' s resting energy requirement ( RER ). When the patient is not eating or is unable to eat , this presents a challenge . Severely flea-anaemic patients can often be too physically weak to be able to eat , rather than not wanting to , so tactics to tempt the patient to eat ( e . g . warming the food ) may not be effective .
The use of feeding tubes to provide nutritional support to feline patients is well documented [ 20 ] . However , many of these require a general anaesthetic to place ( e . g . oesophagostomy tube ). Patients with severe anaemia have a high general anaesthetic risk , so placement of these types of feeding tube may not be commonly performed .
44 Veterinary Nursing Journal