Prospective collection and analysis of error data in a neurosurgical clinic

It is still unknown how often surgical errors lead to clinical impact and contribute to complications for patients. Hence, reliable and detailed prospective collection and analysis of error data is considered essential and a valuable key to error prevention.

In a mono center study, errors and complications were prospectively recorded concerning consecutive patients undergoing elective and emergency neurosurgical procedures. A broad error definition (deviation from an optimal course=DOC) was used to catch as much as possible errors. Each error was scored for type, severity, preventability, and consequence.

More than 1100 consecutive operative cases were studied, 756 cases could be evaluated, among them 529 elective and 227 emergency cases. A total of 190 DOC (25%) were found. The most common DOC was primarily due to (a) equipment failure or missing equipment, then to (b) pre-operative mismanagement, and only to (c) non-optimal procedures. 26% DOC were classified as medical, 69% as non-medical, and 5% as combined. Of all deviations identified, 16% were considered relevant errors, with only 4% slightly impacting the clinical course of the patient. Hence, in less than 1% of all cases a clinically relevant medical error occurred. 19% of all DOC were deemed not preventable. Unexpectedly, the error rate in emergency cases was lower than in elective cases (14% vs. 30%). A propensity for error was discovered with regard to technically complex cranial procedures and patients with higher ASA scores. Without permanent supervision, the documented error rate was significantly lower.

We were able to identify typical reoccurring deviations and discovered several procedure- and patient-related characteristics. Medical errors with relevant clinical impact were rare. Unexpectedly, the error rate in emergency cases was lower than in elective cases. Prospective error documentation and analysis are valuable, but also time-consuming since permanent close supervision is required for maintaining documentation quality.