What are the common types of errors that can occur in electrosurgical units, and how are they detected?

Common errors in electrosurgical units (ESUs) can compromise their effectiveness and safety. One type is power output inaccuracy, where the actual power delivered by the ESU deviates from the set power level. This can lead to either insufficient tissue effect or excessive tissue damage. This is detected using an electrosurgical analyzer, which measures the output power delivered by the ESU into a known load. Another type is return electrode monitoring (REM) failure. The REM system is designed to prevent burns at the return electrode site by monitoring the contact quality between the electrode and the patient's skin. A failure of the REM system can result in burns if the contact is poor. This is detected by visually inspecting the return electrode for damage or contamination and by testing the REM system's functionality using a test load. Insulation failure can also occur, where the insulation on the active electrode breaks down, allowing current to leak to unintended tissues. This can cause burns or other unintended tissue effects. This is detected by visually inspecting the active electrode for damage or cracks in the insulation and by performing a high-voltage insulation test. Activation errors can occur, either unintended activation or failure to activate. This is detected by observing the activation indicator and by testing the activation switches for proper function. Finally, radiofrequency interference (RFI) can occur, where the ESU generates excessive RFI that interferes with other electronic devices. This is detected using a spectrum analyzer to measure the RFI emitted by the ESU.