If a PCA pump delivers an error message stating "does not requested," what could be the issue?

The error message "does not requested" from a PCA (Patient-Controlled Analgesia) pump typically indicates that there is an issue with the patient controller, which is the device that allows the patient to request medication. If the patient controller is malfunctioning—due to a fault in its hardware or software—it may not send the request signals properly to the pump, resulting in the error message.

In contrast, if the medication cartridge were empty, the pump would likely signal a different specific error related to medication delivery. A contact error with the patient would typically manifest differently, possibly affecting how the pump interprets the patient’s requests rather than generating a request failure message. Lastly, a faulty power connection would generally cause the pump to stop functioning altogether rather than produce this specific error message. Therefore, the most plausible cause for the "does not requested" error is a potential fault in the patient controller.