Side errors in neurosurgery.

Eight cases of neurosurgical operations being performed on the wrong side were studied. Safeguards of confidentiality were used. In seven cases side marking was not done and the surgeons felt that had it been done, the mistake would have or may have been prevented. In all but one case the surgeon's normal side check was omitted. Distracting circumstances contributed to the checks being omitted in these seven cases. In the one case where the check was carried out the mistake was made because the patient had been marked on the wrong side. In no case was the mistake made because of ambiguous or absent site data in the imaging or notes. It is concluded that to prevent these mistakes emphasis should be placed on ensuring that the preoperative site check is completed more than on ensuring that unambiguous side information is available in the notes and imaging.