Plus-Hex CLINICAL
Another potential complication post spinal stabilisation are domino lesions . Domino lesions occur most commonly in large-breed dogs with cervical vertebrae stabilisation and those with pre-existing subclinical disc disease . The term domino lesions refers to damage to the discs above and below the fused area . It is thought that domino lesions occur due to permanent immobilisation , resulting in mechanical overload of the adjacent discs . There may also be an impact from natural disease progression , and fusion may accelerate degeneration [ 6 ] .
When nursing these patients during hospitalisation , and at checks and nurse clinics , it is important to recognise signs of clinical relapse after initial recovery . Signs include paraparesis or tetraparesis , ataxia and proprioceptive deficits . Hypoventilation can result from paralysis of the respiratory muscles of the diaphragm and intercostal muscles ; this can progress rapidly to apnoea [ 5 ] .
A top-down approach can be used when monitoring these patients :
Head – responsiveness can be used to assess for pain , neurological status and overall stability . Ocular monitoring can be used to assess for vestibular signs , including nystagmus , anisocoria and the absence or presence of pupillary reflexes [ 7 ] . Facial checks can identify signs of Horner ' s syndrome , including ptosis ( eyelid drooping ), enophthalmos ( sunken eye ) and conjunctival hyperaemia ( raised and reddened third eyelid ) [ 8 ] . Mucous membrane colour provides an indication of circulatory status , oxygenation , potential anaemia and hydration .
Chest – the respiration rate and character should be monitored throughout the patient ' s stay , with blood gas analysis if inadequate ventilation is suspected .
Temperature – this should be monitored closely as these patients may be unable to regulate their temperature , becoming either hyper- or hypothermic [ 1 ] . Hyperthermia can also occur if a patient is unable to pant , especially if it is unable to lift its head . These patients should not be left unmonitored if active heating aids are being used .
Neurological deterioration – monitor for unexpected or extreme deterioration of the patient , including proprioceptive deficits , decrease in spinal reflexes , signs of pain , poor coordination and ataxia [ 8 ] .
These patients are at risk of myelomalacia ( Table 2 ). The pathophysiology of this condition is poorly understood ; however , it may be the result of ischaemia , haemorrhage , trauma or necrosis of the spinal cord following acute injury and extensive damage to the intramedullary spinal vasculature .
These patients have a very poor prognosis ; without treatment , they often succumb within 48 – 72 hours as the necrosis expands cranially or caudally [ 5 ] .
Table 2 . Signs of myelomalacia .
Signs Hyperthermia Abnormal or altered respiration Ascending panniculus reflex Altered mentation Weakness Inappetence Muscle atrophy Negative deep pain perception
Pain assessment – pain monitoring and management is important in these cases , with multimodal analgesia being appropriate [ 4 ] . Compromised pain sensations , which can occur with these patients , include allodynia or hyperaesthesia and dysaesthesia . Neuropathic pain can also present in these patients from central or peripheral nervous system injury , in which pain is produced from direct stimulation of the nervous tissue [ 5 ] .
Pain assessment of these patients can be difficult , with pain-scoring systems often being deceptive . Pain scores can still be used to track progress , but should not be used as a standalone assessment .
Additional signs of pain
• Decreased activity level or interaction
• Depressed mentation
• Unexplained vocalisation
• Increased cervical muscle tone
• Intermittent spasms of the neck
• Restricted range of motion of the neck or forelimbs
• Stiffness of any part of the body
• Inability to find a resting position
• Unwillingness or inability to eat and drink [ 9 ] .
Autonomic signs should be monitored during rest and interaction , including salivation , respiratory rate , heart rate and pupil dilation . An increase in any of these can indicate pain . Thorough palpation of these patients to assess pain is encouraged ( Table 3 , page 26 ).
Volume 39 ( 1 ) • February 2024
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