Peripheral Edema due to Neuraxial Opioid Infusion: Still an Underrecognized Predicament

Peripheral Edema due to Neuraxial Opioid Infusion: Still an Underrecognized Predicament

The discovery of opioid receptor in the spinal cord in the 1970s opened the door for spinally mediated analgesia. The demonstration of profound analgesia by intrathecal opioid leads to the current popular utilization of the intrathecal opioid delivery pump to treat varieties of intractable painful conditions that have not responded to conventional treatment. The introduction of intrathecal opioid infusion marks one of the most important breakthroughs in pain management in the past decades. The main advantage of intrathecal opioid is that it produces profound analgesia in doses much smaller than would be required for comparable analgesia if administered systemically. Another advantage is that intrathecal opioid, unlike local anaesthetics, does not cause any sensory, motor, or autonomic blockade. With the increasing utilization of intrathecal opioid delivery pump therapy since 1980s, some clinically relevant side effects have been increasingly recognized. Among them, pruritus, nausea, vomiting, urinary retention, and respiratory suppression are commonly reported. Peripheral edema, as a result of intraspinal opioid infusion therapy, is somewhat less recognized.