INTRODUCTION:Obesity,osteophytic spine with deformities,variant epidural anatomy and suboptimal position predispose anaesthesiologist to challenges.We aimed to determine the utility of preprocedural ultrasound scan compared with the conventional blind technique for epidural neuraxial blockade in patients
undergoing hip and knee replacement surgeries in terms of technical difficulty,clinical efficacy,safety and patient comfort.
MATERIAL&METHODS:210 patients aged 50-88 years with BMI 30-45kg/m2 and osteophytic spines including abnormalities were randomized in two groups.Both groups received combined spinal epidural anaesthesia(CSEA).Epidural depth was confirmed by LOR technique.In group'B' preprocedural ultrasound was done to identify level of intervertebral space in median longitudinal view and needle insertion
site.Epidural depth was measured from skin to midpoint of posterior complex in median longitudinal and transverse view.Two tailed tests,Pearson correlation coefficient and Bland-Altman analysis with 95% confidence interval were calculated.
RESULTS:Both groups were similar in physical characteristics.Ultrasound improved success of CSEA at 1st attempt from 74.28% in group'A' to 85.71% in group'B'(p-0.038).Fewer needle insertion attempts(p- 0.013),passes(p-0.022) and anaesthesiologist(p-0.044) were required in group'B' thereby,ultrasound
reduced the technical difficulty.Ultrasound determined the most neutral space and its orientation in scoliosis.Ultrasound precisely determined the depth of epidural space with insignificant difference of 0.030cm(p-0.66) and Pearson correlation coefficient of 0.977 using both views.Bland Altman analysis revealed mean difference of 0.007cm[-0.044,0.030].Ultrasound improved efficacy and safety with higher
patient satisfaction score(p-0.019) and decreased procedural complications(p-0.003) like inadvertent dural puncture(p-0.013).
CONCLUSION: Preprocedural ultrasound scan improves success rate for epidural neuraxial blockade and can be used as an adjunct to lumbar epidural blocks in obese patients with osteophytic abnormal spines.Therefore,lumbar ultrasound scan is a valuable skill to learn to ensure higher standards of healthcare.

06 / Use of ultrasound for epidural neuraxial blockade in hip and knee replacement surgeries: A randomised controlled study