Drug overdose due to malfunction of a patient-controlled analgesia machine -A case report-.

Patient-controlled analgesia (PCA) provides excellent pain control and high stability, thereby minimizing the incidence of adverse effects. However, one of our patients experienced respiratory depression and hypotension within 30 minutes of initiation of PCA therapy. We discovered that machine malfunction caused continuous activation of the PCA button, resulting in a drug overdose. The PCA machine was sent to the manufacturer, who found an electrical short in the PCA button. All PCA units of the same make and model were immediately removed from hospitals and replaced with redesigned units without defects in the PCA button. We have used the improved machines without any problems. The purpose of this report is to raise awareness of this type of malfunction in PCA units in order to help prevent adverse events in the future.