Here is a disturbing article by Mike Adams on the most common surgical mistakes, in US operating theatres. All of these could cause great anxiety and nightmares, such as having the wrong organ removed, such as a testicle or breast, then having to have the bad one out anyway. Instruments are sometimes left inside, but in Australia there is a checklist that is scrutinised, so maybe all is well. But I had a nurse girlfriend, back in the day (1970s) who told me that during one operation she was assisting in, the surgeon suddenly took ill and vomited in the patient’s open body cavity! I suppose it went through the mask, or the mask went with it! They cleaned the mess it up, and gave antibiotics. I don’t recall whether or not the incident was reported or just covered up. The nurses would never rat on the all-mighty surgeons, her included.