Abstract
Patient-controlled analgesia (PCA) is a newer technique for pain management. Patients are allowed to self-administer small analgesic bolus doses into a running intravenous infusion, intramuscularly, subcutaneously or even into the epidural space. Demands are usually controlled by computer-driven infusion pumps, but can also be delivered by disposable devices. Clinical experience demonstrates that individual variability in pain sensitivity and analgesic needs are of utmost importance. In contrast to earlier expectations, opioid consumption is usually higher than with restrictive conventional dosing regimes, but without an increase in serious side effects. Patients' acceptance is generally enthusiastic because of the possibility of self-control. PCA has proved its importance for pain studies, e.g. for algesimetry, to determine predictors of postoperative pain, to describe drug interactions, to evaluate the concept of pre-emptive analgesia or for pharmacokinetic designs. It is concluded that PCA results have been urgently required in order to change the mind of physicians and nursing staff with respect to individual pain management strategies. Once this goal is achieved, PCA concepts should also be used for the improvement of more conventional techniques.