Patient-Controlled Analgesia in Cancer Pain

Patient-controlled analgesia (PCA) is indicated for patients experiencing moderate to severe nociceptive cancer pain unrelieved by strong oral or transdermal opioids. This is appropriate in two situations: 1) the impossibility of oral or transdermal administration, and 2) inadequate control of breakthrough pain. Intravenous morphine remains the most frequently used opioid in PCA devices. Background infusion provides effective management of baseline pain; its dosage is calculated according to the daily amount of opioid previously taken by the patient. The bolus dose ( ranging between 1/24 and 1/10 of the daily amount) is used as the breakthrough dose to treat breakthrough pain. In the case of renal insufficiency, fentanyl or sufentanil can be used. If the patient experiences refractory pain or opioid tolerance, it is possible to associate morphine with low doses of ketamine. Lastly, in the most difficult cases, the spinal route ( epidural or intrathecal) may be an effective alternative in terms of improving of the quality of life of end-of-life patients.