Pain after surgery is common, often severe and largely unnecessary. Effective relief of post-operative pain is vital, and not just for humanitarian reasons. Such pain probably prolongs hospital stay, as it can affect all organ systems, including: respiratory (e.g. reduced cough, sputum retention, hypoxaemia); cardiovascular (e.g. increased myocardial oxygen consumption, ischaemia); gastrointestinal (e.g. decreased gastric emptying, reduced gut motility, constipation); genitourinary (e.g. urinary retention); neuroendocrine (e.g. hyperglycaemia, protein catabolism, sodium retention); musculoskeletal (e.g. reduced mobility, pressure sores, increased risk of DVT); and psychological (e.g. anxiety, fatigue). There is now evidence that post-operative pain relief has significant physiological benefit (Charlton 1997).
Not only can it result in earlier discharge from hospital, but it may also reduce the onset of chronic pain syndromes. Nevertheless, post-operative pain remains grossly under treated, with up to 70% of patients reporting moderate to severe pain following surgery (Pyati 2007).
The goal for postoperative pain management is to reduce or eliminate pain and discomfort with a minimum of side effects as cheaply as possible (Breivik 2008). The standard method of treating postoperative pain in the developed world is an intramuscular opioid (usually diamorphine or morphine), but other analgesics (paracetamol, NSAIDs) and local anesthetics may also be used (Taylor 2001). Nonpharmacological treatments include hypnosis, transcutaneous electrical stimulation, and hot and cold application.
Breivik H, Stubhaug A. Management of Acute postoperative pain: still a long way to go! Pain 2008; 137: 233-4.
Charlton E. The management of postoperative pain. Practical Procedures 1997; 7: 1-7.
Pyati S, Gan TJ. Perioperative pain management. CNS Drugs 2007; 21: 185 - 211.
Taylor M S. Managing postoperative pain. Hosp Med 2001; 62: 560-3.
How acupuncture can help
Systematic reviews suggest that acupuncture and ear acupuncture are useful adjunctive treatments for post-operative pain management (Sun 2008; Usinchenko 2008). Several recent randomised controlled trials have found acupuncture and electroacupuncture to reduce post-operative pain, the use of patient-controlled analgesia (opioids), and post-operative nausea and vomiting (Salmeddini 2010; Larson 2010; Parthasarathy 2009; Wu 2009; Grube 2009; Wong 2006).
In general, acupuncture is believed to stimulate the nervous system and cause the release of neurochemical messenger molecules. The resulting biochemical changes influence the body's homeostatic mechanisms, thus promoting physical and emotional well-being. Stimulation of certain acupuncture points has been shown to affect areas of the brain that are known to reduce sensitivity to pain and stress, as well as promoting relaxation and deactivating the 'analytical' brain, which is responsible for anxiety (Wu 1999).
Acupuncture may help relieve post-operative pain by:
- altering the brain's chemistry, increasing endorphins (Han 2004) and neuropeptide Y levels (Lee 2009; Cheng 2009), and reducing serotonin levels (Zhou 2008).