1. Aims To determine the discrepancy between conventional landmark technique and Ultrasound to identify site of insertion of Lumbar CNB. No patients should have their spinal/ CSE sited above the L 2-3 interspace. Introduction Methods Results Accuracy of landmark technique: 45.4% Increased BMI & difficulty of palpation of landmarks >> Statistically significant decrease on accuracy (p=0.0.32* & 0.019* respectively) 7 out of 68 (10.3%) patients had their spinal/CSE placed above L 2 level No statistically significant correlation between the experience of operator & accuracy (p=0.311*) * Fisher’s Exact t-Test (2-tailed) Key Findings Recommendations All patients having a lumbar CNB should have ultrasound of their spine to identify the correct vertebral level Easy availability of curvilinear probes Promote staff education & awareness References 1.Shiraishi N, Matsumura G. What is the true location of Jacoby’s line? Okajimas Folia Anat Jpn 2006; 82: 111–5 2.Render CA. The reproducibility of the iliac crest as a marker of lumbar spine level. Anaesthesia 1996; 51: 1070–1 3.Halpern SH, Banerjee A, Stocche R, Glanc P. The use of ultrasound for lumbar spinous process identification: A pilot study. Can J Anaesth 2010; 57: 817–22 Ultrasound Analysis of the Accuracy of Landmark Approach to Central Neuraxial Blocks in Anaesthesia Lie J 1, Venkataraju A 1, Bhatia K 2 & Kochhar P 2 1 Specialty Trainee in Anaesthesia, 2 Consultant Anaesthetist Insert your logos Insert your QR Code Three experienced US operators retrospectively performed the US of spine post-operatively in 91 patients having a lumbar CNB by landmark method From January to March 2013 Location: St Mary’s Hospital & Manchester Royal Infirmary Patient’s demographics, anaesthetic details of CNB & documentation of CNB were noted, including vertebral level at which CNB was performed US spine was then used to identify the actual vertebral level in which the block was performed at using the visible skin puncture point Level was compared with documented vertebral level Difficulty in palpating lumbar anatomy & iliac crest was also recorded SpecialtyNumber of Patients Obstetrics51 Orthopaedics23 Gynaecology8 Vascular4 Urology3 GI Surgery2 PopulationAccuracySpinal/ CSE above L 2 % (n) Overall45.4%10.2% (7) General54.3%16.2% (6) Obstetrics39.2%3.2% (1) Block Level: USG Vs Documentation Degree of Discrepancy Small sample size Heterogeneous population - Obstetric/Non- obstetric, predominantly females Skin puncture site & positioning Operator bias Limitations Correct identification of the vertebral level during a central neuraxial block (CNB) would avoid needle damage to the spinal cord which usually ends at L 1-2 in adults An imaginary horizontal line joining the posterior iliac crests (Tuffier’s line) is the most commonly used anatomical landmark by anaesthetists for CNB as it passes through the L 4 vertebral body 1, 2 Evidence suggests that ultrasound (US) imaging of the spine by an experienced operator leads to correct identification of vertebral level in >90% of the patients 3 69% (63) Spinal 6% (5) CSE 25% (23) Epidural 40.7% (37) of operators were consultants, followed by 29.7% (27) were senior trainees 91 patients Median age: 36 yrs Median height: 164.5 cm Median weight: 77 kg Median Body Mass Index (BMI): 27.9 Kg.m -2