Patient-controlled analgesia: An efficient therapeutic tool in the postoperative setting

Patient-controlled analgesia (PCA) is one of the newer techniques for pain management. It was developed in reaction to the large number of unsatisfied postoperative, patients suffering from moderate to severe pain despite the availability of potent analgesic drugs. With PCA, patients are allowed to self-administer small analgesic doses into a running intravenous infusion, intramuscularly, subcutaneously or even into the spinal space. Clinical exp erience soon demonstrated that individual variability in pain intensity and analgesic needs was extremely large. Psychological factors seem to be as i mportant as the surgical trauma. Opioid consumption is usually higher than with conventional regimens, but without serious side effects. Although pati ents generally prefer self-control, pain relief is not necessarily better t han with well-conducted conventional techniques. In addition to routine cli nical pain management, PCA has proven its importance in research, e.g. for pain measurement, to determine predictors of postoperative pain, to evaluat e drug interactions and the concept of pre-emptive analgesia, or for pharma cokinetic designs. PCA has been extremely important in order to change the mind of physicians and nursing staff with respect to individual pain manage ment strategies.