The International Association for the Study of Pain (IASP) has designated 2017 as the “Global Year Against Pain After Surgery”.
The International Association for the Study of Pain (IASP) has designated 2017 as the “Global Year Against Pain After Surgery” in an effort to improve the management of post-surgical pain. IASP aims to increase awareness, provide information and educate health professionals and researchers on post-surgical pain, and hopes to encourage world leaders and organisations to support policies that would facilitate and enable this.
This article presents a basic introductory overview of the information provided by the IASP as part of the Global Year campaign.
Pain is a normal side effect of surgical incisions / tissue trauma. The severity and duration of pain after surgery will vary depending on the type, location and intensity of the surgery, individual patient factors (genetic and environmental) and the mode and quality of pain management following surgery.
Acute post-surgical pain involves nociception and sensitisation. Nociceptors - pain sensing nerve cells - are stimulated when tissue is damaged through surgical incision and transmit information via the spinal cord to the brain where it is processed and perceived as pain. Nociceptors become more sensitive (sensitisation) and cause hyperalgesia (increased sensitivity to pain) due to local inflammation and the release of “mediators” – proteins released during and following surgery, such as those involved in the immune response – amongst other factors such as a drop in tissue pH. With nociceptor signalling intensified, the nervous system will begin to adapt and neurons in the central nervous system also become sensitised, further enhancing pain signalling and maintaining hyperalgesia. Nerve damage during surgery is another potential cause of ongoing post-surgical pain in the form of neuropathic pain.
If nociceptive sensitisation and neuropathic pain aren’t properly controlled following surgery, the risk of chronic post-surgical pain (CPSP) is elevated. According to the IASP, the definition of CPSP is pain (new or intensified existing pain) that results from the surgical process itself, and not from infection or any other cause, and that persists 2 – 3 months after surgery.
Numerous pharmaceutical agents are able to control or prevent pain and sensitisation after surgery, such as analgesics, local anaesthesia and adjuvant medications. Typically, opioid (narcotic) medications, non-traditional opioids or combination analgesics containing opioids are administered. Opioids may be used pre-operatively as well as post-operatively; however, long term use is unfavourable for numerous reasons such as the development of opioid dependence and emerging evidence that suggests that opioid medications may actually increase pain signalling and induce hyperalgesia.
A rise in focus and investigations on pain after surgery over the last two decades has seen vast improvements in the management of post-surgical pain. Previous generations saw a staggering ~50% of surgeries resulting in severe post-surgical pain. Surgeries were overall more invasive, traumatic, and the resulting pain was poorly managed in and out of the hospital. Nowadays, with minimisation of surgical invasiveness, enhanced surgical and anaesthetic techniques, a pre-emptive, multimodal and personalised approach to pain management that aims to reduce reliance on medications such as opioids, and with adequate patient assessment and follow-up, the severity of pain after surgery and the incidence of CPSP have greatly improved.
For more information on pain after surgery, easy to understand and expert fact sheets have been produced by the IASP that are free to download via the following link: http://www.iasp-pain.org/globalyear.