[The risk of anaesthesia. Investigations based on 153,660 anaesthetic procedures (author's transl)].

153,660 protocols of general and local anaesthesias were evaluated according to the complications observed during anaesthesia. The complications recorded were analysed with respect to the following criteria: type of anaesthetic procedure, experience of the anaesthesiologist, urgency of the operation and pre-operative condition (risk group) of the patient. The study shows that under the requirements of anaesthetic treatment at a university clinic, the degree of risk connected with anaesthesia is only slightly dependent on the type of the anaesthetic procedure and the experience of the physician performing the anaesthesia. Distinct differences in the complications recorded are found to be dependent on the urgency of the operation (cardiovascular and technical complications) and on the pre-operative condition of the patient (cardiovascular complications). A further decrease of the anaesthetic risk is only possible if all measures for optimal preparation before an operation are fully met and compromises are avoided to the utmost. However, spectacular improvement must not be expected with these measures.