[Complex regional pain syndrome. Current status]. / Síndrome doloroso regional complejo. Estado actual.

Complex regional pain syndrome (CRPS) is a disorder or group of disorders that develop as a consequence of previous trauma with or without evident nerve injury. The syndrome is characterized by presence of spontaneous pain, hyperalgesia and allodynia, sensitive changes, blood flow changes, sweating, and trophic changes. The disease is characterized by symptoms of acute inflammatory states as well as by chronic neuropathic changes. Pain is associated with changes generated by the autonomic nervous system. Spinal neurons can increase their sensitivity to these autonomic changes. At a supraspinal level, reorganization of somatosensorial cortex is seen. Creation of diagnostic criteria has been difficult due to the plentiful symptoms of CRSP. Sympathetic blockade with phentolamine is the most commonly approved examination to diagnose sympathetic maintained pain. Several strategies have been used for treatment of CRPS, but with none of these has sufficient evidence of treatment effectiveness been afforded.

Management of opioid-induced bowel dysfunction in cancer patients.

The gastrointestinal (GI) effects of morphine and other opioids may result in opioid-induced bowel dysfunction (OBD) and the need for treatment. Although OBD is very common in morphine-treated patients, it is usually under-diagnosed. Opioids deliver their GI effect through central and peripheral mechanisms. Laxatives are the pharmaceuticals prescribed most in this area. Prokinetics as well as cholinergic agonists have been used satisfactorily. One-third of patients with OBD have to be treated rectally. The use of opioid antagonists has been favored, but the bioavailability of oral forms is poor. Opioid antagonists with a quaternary structure have a high affinity for peripheral opioid receptors and therefore do not interfere with the analgesia, nor do they generate alkaloid withdrawal syndrome. Opioid rotation is another strategy for maintaining or improving analgesic quality directed toward decreasing the effects of previous opiates on the GI tract.