Title: Incidence and risk factors of Postdural Puncture Headache: Prospective cohort study design

Abstract Background: Post-dural puncture headache is one of the complications following spinal anaesthesia and accidental dural puncture. Several modifiable risk factors contribute to the development of headache after lumbar puncture which includes needle size, needle design, direction of the bevel and number of lumbar punctures attempts. This study aimed to assess the incidence and risk of postdural puncture headache.Methods: This prospective cohort study design was conducted using a consecutive sampling method. Regular supervision and follow up were made. Data was entered in to Epi info version 7 software and transported to SPSS version 20 for analysis. Odd ratio and 95% confidence interval was computed. The findings of the study were reported using tables, figures and narration. Variables that were found to be candidate (p value < 0.25) on binary logistic regression entered into a multiple logistic regression analysis to identify independent predictors of postdural puncture headache.Results: One hundred fifty eligible study participants were included in our study of which 28.67% had developed postdural puncture headache. This study found that needle size, number of CSF drops and multiple attempts as independent predictors of postdural puncture headache at significant level (p < 0.05). In addition, twenty five needle was identified as strongest pre-operative independent predictor with PDPH (AOR = 4.150, CI = 1.433- 12.021)Conclusions: Recent study revealed that small size spinal needle was much better to large size cutting spinal needle regarding the frequency of postdural puncture headache. Besides, frequent attempts during lumbar puncture and increased CSF leakage were associated with the events. In view of this, we recommend the use of small size spinal needle; avoid more leakage of cerebrospinal fluid and multiple attempts in spinal anesthesia and lumbar puncture.