Failed spinal anaesthesia is defined as a partial or incomplete spinal block requiring supplemental analgesia or conversion to general anaesthesia. The incidence of failed spinal anaesthesia varies from centre to centre and time to time within the same centre. A retrospective analysis of almost 5000 spinal anaesthesia by Horlocker and colleagues reported 1% failure rate. Parikh KH et al have found that with careful performance of technique , failure rate of as low as 1% is attainable. Sprung Juraj et al concluded that most reliable method of determining the potential for technically difficult block is the examination of patients for quality of landmarks and other obvious factors. the suggestion from these report is that with meticulous attention to detail and appropriate management , most failure of spinal anaesthesia could be prevented . 

This observational study will be conducted to investigate the incidence of failure of spinal anaesthesia , first attempt success, conversion to general anaesthesia and factors associated with failed spinal anaesthesia  in obstetric patients requiring caesarean section in King Georges Medical  University ., Lucknow.