Current and developing methods of patient-controlled analgesia.

Moderate-to-severe acute postoperative pain is commonly controlled with opioids administered via programmable intravenous (IV) patient-controlled analgesia (PCA) infusion pumps. Intravenously administered opioids provide effective relief of postoperative pain, and IV PCA enables patients to control their level of analgesia, which has advantages over nurse-administered approaches, including more satisfied patients and improved pain relief. Unfortunately, commonly used opioid analgesics can cause significant adverse effects. Furthermore, IV PCA has drawbacks, such as device programming errors, system errors, medication errors, limitations in patient mobility, and potential for IV tubing kinks, clogging, and transmission of infection. The IV route of administration is also characterized by a rapid, high peak in analgesic drug concentration followed by rapidly decreasing concentrations. Consequently, respiratory depression, excessive sedation, and inadequate pain control can occur. Furthermore, the technical assembly of an infusion pump is often complex and time-consuming. PCA modalities that incorporate superior opioid analgesics, such as sufentanil, and novel noninvasive routes of administration offer great promise for enhancing the patient and caregiver experience with the use of postoperative PCA.