This case highlights several topics that you may wish to explore to develop your knowledge. Other papers in the ‘Recommended Reading’ section for October 2024 will also give further insights.
Mr P was a challenging patient to manage with very fixed ideas regarding treatments that were acceptable to him. Information about why patients may display challenging behaviour and how to manage it can be found on the MDU website1.
Harnessing the placebo effect can be useful in managing patients with chronic pain. McCarter2 and Bishop et al3 provide an introduction to the subject. The mechanisms to explain this effect continue to be the subject of research4 but may involve opioids, cannabinoids, serotonin and dopamine5.
While the placebo effect may have contributed to Mr P’s experience, other factors might have been involved. Local anaesthetics have been observed to break the pain cycle6 and Arner et al7 demonstrated that the duration of pain relief can be much longer than the duration of local anaesthetic action. Possible mechanisms for this include effects on hypersensitive nociceptors and peripheral A-delta and C fibres and CNS effects from systemically absorbed drugs. Blocking release of noradrenaline from sympathetic efferent nerves, reduced sprouting of damaged nerves in the spinal ganglia and a reduction in the hyperexcitability of nociceptive nerves in the spinal cord dorsal horn have all been suggested8.
- What factors do you think contributed?
