Plus-Hex CLINICAL size of 370 rabbits , myiasis was the reason for 10.9 % of deaths or euthanasia . Turner et al . [ 1 ] recorded the death rate in myiasis cases as 44.7 %. Turner et al . [ 1 ] stated that several factors increase the risk of myiasis in rabbits , including rabbits being over the age of 5 years ( 3.8 %), female rabbits being entire ( 3.3 %) and an increase in climate temperature ( an increase of 1 ° C increases the myiasis risk by 33 %). Therefore , due to the increase in rabbit myiasis cases seen in veterinary practices and rabbits ' predisposition to this condition , it is important to understand the nursing care implications for the critical myiasis rabbit .
Treatment for the stable myiasis rabbit includes removing the maggots , cleaning the wound , using pesticides and administering a course of pain relief and antibiotics [ 12 , 31 ] . However , unstable rabbits can deteriorate ( as seen in ileus ) with hypovolaemic shock and lowered blood pressure [ 32 ] . In these cases , the following need to be considered for each patient : anaesthesia or sedation , thermoregulation , hydration , nutrition , treating underlying conditions and quality of life [ 12 , 33 ] .
Pain and stress were the main factors affecting rabbit survival in veterinary practices [ 34 ] . This supports the focus of this article being on pain management in the myiasis rabbit . It is important for VNs to have knowledge of pain management in the critical myiasis rabbit , as pain can induce further stress , triggering corticosteroid release , which can lead to organ failure and even death [ 35 ] .
As a prey species , rabbits hide their pain [ 36 ] , so pain assessments are often based only on their reduced mobility and alertness to their surroundings [ 35 ] . In a study carried out by Shaw et al . [ 19 ] the rabbit participants were observed through a camera and disturbed only occasionally for close monitoring . This could indicate the use of cameras in veterinary practices to monitor and assess pain without interfering with the patient more than necessary . Assessing rabbits without them knowing they are being watched would be less stressful for them , which could lead to more accurate assessment results .
Shaw et al . [ 19 ] assessed the RbtGS [ 37 ] ( Appendix A ) with VNs and identified major concerns , including unclear images , vague descriptions and its exclusion of lop-eared breeds . In a feedback survey , the participants stated that these issues made it difficult to score the rabbits accurately [ 19 ] . Issues were also identified by Benato et al . [ 11 ] , who argued that there is a lack of a specific multimodal composite pain scale for the species , with 71 % of VNs not using a pain scale for rabbits . The composite pain scale for assessing and quantifying pain in rabbits ( CANCRS ) [ 38 ] ( Appendix B ), which included the RbtGS , was assessed in clinical practice . However , none of the severe pain cases were identified using this scale [ 38 ] . The scale was comprehensive but the physiological parameters , such as heart rate , cannot be accurately assessed in rabbits due to stress [ 36 ] . Therefore , Benato et al . [ 18 ] produced a new multidimensional Bristol Rabbit Pain Scale ( BRPS ), comprising six categories on a four-point scale , which includes a category for ear position and movement , unlike the RbtGS . The final version of the BRPS [ 18 ] ( Appendix C ) included posture and locomotion , eyes , ears and grooming , which were not included in the RbtGS or CANCRS [ 18 ] . The BRPS also gives clear instructions to help reduce stress , in order to obtain more accurate and valid pain scores in rabbits [ 18 ] .
In severe cases , myiasis causes tissue damage , shock and rapid deterioration of the rabbit [ 31 ] . These patients will require effective fluid therapy and active warming to address circulatory shock [ 25 ] . Oglesbee and Lord [ 10 ] suggested that fluid therapy is essential to recovery in critically ill rabbits and those that are severely dehydrated . Intravenous fluid therapy is considered best practice [ 39 ] compared with subcutaneous therapy , which takes several hours for absorption and induces stress [ 40 ] . In paediatric cats , intravenous fluid therapy is used to improve tissue perfusion and prevent hypovolaemic shock [ 2 ] . Like paediatric patients , rabbits have a higher fluid requirement and can rapidly become dehydrated [ 2 , 41 ] . Therefore , as indicated , intravenous fluid therapy should be used in rabbit myiasis cases .
Rabbits ' fluid requirement for overall shock therapy is 100 ml / kg within the first hour [ 25 ] , but should be considered on a patient-by-patient basis , as Varga [ 42 ] states the recommended maintenance is 100 ml / kg / day . It is also important to remember that oral fluid intake is the most ideal form to restore normal hydration levels , but this is often difficult in hypovolaemic patients that present signs of poor mentation [ 43 ] .
In a study by Zhang et al . [ 44 ] the combination of fluids ( 6 % hydroxyethyl starch 130 / 0.4 , lactated Ringer ' s solution and 7.5 % hypertonic saline solution ) and hypotensive resuscitation led to higher perfusion rates . This included stabilising perfusion and a reduction in blood loss . Voldby and Brandstrup [ 43 ] agreed that the use of restrictive fluid therapy avoids fluid overload while returning to normovolaemia . However , according to Varga [ 42 ] , Hartmann ' s , lactated Ringer ' s solution and 0.9 % NaCl fluids are the most appropriate choice for replacement and maintenance in rabbits . Further research is needed on the best fluid solutions to use in the critical myiasis rabbit , as this is not covered in this article .
For effective intravenous catheterisation of the marginal ear vein , 30 min prior to placement [ 45 ] , a eutectic mixture of local anaesthetics ( EMLA ) topical cream should be applied to the ear after shaving the site and then covered with a bandage [ 39 ] . In a study by Keating et al . [ 46 ] , EMLA cream completely prevented severe pain in rabbits , indicating its use as part of catheterisation protocols in practice . Specific EMLA doses are used in humans to prevent toxicity and systemic adverse effects [ 47 ] , but this medication is used under the prescribing cascade and doses may vary under veterinary direction [ 48 ] . In humans , EMLA is indicated to be safe to apply topically to the genitalia but clinical parameters advise that the cream
Volume 38 ( 4 ) • August 2023
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