Objective:

Neuraxial blocks are increasingly used for anesthesia, postoperative analgesia, and pain management. In spite of advancements in neuroaxial block procedures, difficulty or failure to obtain satisfactory block is still the main isue. Data on operational failure which can be defined as inability to achieve planned blockade technique, its inadequacy or deficiency, differ due to the variability in description of the criteria of failure, and also methodologic differences. In this study we aimed to determine the rates of failure and causal correlations in cases with neuraxial blocks as to guide future attempts.

Material and Method:

After the approval of Research Committee, records of 7263 patients aged ≥18 years who had received neuraxial blocks between 1998-2008 were examined. Patients (n=297) who were given epidural blocks under general anesthesia were excluded from the study. From the records of the remaining 6966 patients, demographic, and medical historical data of the patients, coexisting health problems, methodologic, and operational features, causes and criteria of failure, as well as surgical details were extracted. Chi-square, Student-t, and Mann-Whitney U tests were used for statistical evaluations. Among parameters deemed as significant indicators of failure, independent risk factors were determined using logistic regression analyses.

Results:

The neuraxial blocks were performed for 10,69 % of our surgical anesthesia cases. Total failure rate was 5,4 %, being 3,9 % in spinal, 10,9 % in epidural, 6,4 % in combined spinal-epidural blocks, respectively. Independent risk factors were detected as paramedian approach (p<0,001/OR 30,8), peripheral vascular disease (p<0,001/OR 2,5), epidural block (p<0,001/OR 2,6), duration of surgery (p<0,001/OR 2,3), requirement for expert experience (p<0,001/ OR 1,9), chronic obstructive pulmonary disease (p=0,014/OR 1,7), and body weight (p=0,023/OR,1,0).

Conclusion:

In conclusion, careful patient evaluation, selection of anesthetic technique appropriate for surgical procedure, earlier consultation to an experienced expert. and keeping the patient records accurately will decrease the rate of operational failure and increase the safety of the patient.

Keywords: Neuraxial blocks, spinal, epidural, combined spinal epidural