How should a technician respond to significant respiratory depression observed during anesthesia?

In the context of significant respiratory depression observed during anesthesia, the most appropriate response involves immediately lightening the anesthesia. This action is crucial because respiratory depression indicates that the patient is not able to ventilate effectively, which can lead to severe complications, including hypoxia or respiratory failure.

Immediately reducing the anesthetic depth allows the patient's respiratory function to recover. By lightening anesthesia, you are minimizing the effects of the agents that may be suppressing the respiratory drive, thus enabling a return to normal respiratory patterns and improving oxygen levels in the bloodstream.

The other options, while they may seem viable in different scenarios, are not suitable in this case. Monitoring more closely is important but does not address the immediate need to improve the patient's respiratory status. Increasing the anesthetic depth or administering more sedatives would further exacerbate respiratory depression, worsening the situation rather than alleviating it.