Science classes are taught in these classrooms, where experiments may be performed safely.

The advent of endoscopic stapling was also a major advance so that complicated procedures such as pulmonary lobectomy could be performed safely.

Under some circumstances, lumbar puncture can not be performed safely (e.g. a severe bleeding tendency).

Anatomic resections are generally preferred because of the smaller risk of bleeding and biliary fistula; however, non-anatomic resections can be performed safely as well in selected cases.