Ultrasound-guided Quintuple block of the thigh and knee joint - mapping the location of the local anaesthetic fluid

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1 Ultrasound-guided Quintuple block of the thigh and knee joint - mapping the location of the local anaesthetic fluid Poster No.: C-0415 Congress: ECR 2012 Type: Authors: Keywords: DOI: Scientific Paper A. Christensen, F. Baerentzen, T. Jansen, K. Jensen, J. Boerglum; Copenhagen/DK Extremities, Interventional non-vascular, Musculoskeletal soft tissue, MR, Normal variants, Experimental investigations /ecr2012/C-0415 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 8

2 Purpose Many surgical procedures can be performed without the need for general anaestesia by instead using regional anaestesia in the form af a regional block. This reduces the risk of complications associated with general anaestiasia but he distribution, position and the extent of the injectate following the application has not been described for many nerve blocks used in regional anaestesia procedures. The Quintuple nerve block is administered to provide surgical anaesthesia for surgical procedures like knee Arthroscopy and ACL reconstruction among others. The local anaestesic fluid is injected in 5 places using ultrasound guidance which enables a precise anatomical distribution of the injectate. After the application the distribution and the extent of the injectate which corresponds to the anaestesic effect has not been mapped. The aim of the present study was to map the 5 fluid areas of the Quintuple block using high definition 3-Tesla MRI sequences in three planes. Images for this section: Fig. 1: Axial view of the adductor-group and the injectates in situ Page 2 of 8

3 Methods and Materials One healthy volunteer was placed on a Magnetic Resonance (MRI) certified stretcher during the whole séance. First a MRI T2 spin echo fat-saturated sequences were performed in 3 planes: coronal, sagittal and axial plus as a 3-D sequence to rule out the presence of pre-injection fluid or other findings. Then 5 injections of saline were administered as when applying a Quintuple block; i.e. a total of 40 ml: Injected volume was for the femoral nerve 10 ml, for the lateral femoral cutaneous nerve, for the obturator nerve: the anterior branch and the posterior branch 5 ml each and for the sciatic nerve 15 ml After installation of injectate a repetition of the former MRI-protocol was performed. Nerve, muscle and vessel structures could be easily identified on the MRI scan and the findings reproduced with comparison to anatomical and MRI-atlases. Images for this section: Page 3 of 8

4 Fig. 2: Sagittal view of the adductor-group and the injetates in situ Page 4 of 8

5 Results The pre-injection MRI confirmed that no fluid was present in any of the five injectionareas before the injection of the saline. All MRI-images was evaluated to be of good qaulity without artefacts by a consultant radiologist. All 5 fluid areas were identified both regarding boundaries and adjacent structures in all three planes. All the above mentioned nerves were identified on the high resolution MRI sequences and the fluid distribution adjacent to these could be identified as being correct in all cases. Images for this section: Fig. 3: Axial view presenting injectate in relation to the sartorius muscle Page 5 of 8

6 Fig. 4: Coronal view presenting the injectate in relation to the intermedius muscle Page 6 of 8

7 Fig. 5: Sagittal view presenting the injectate in relation to the isciadic nerve Page 7 of 8

8 Conclusion The positioning and fluid distribution of the ultrasound-guided Quintuple block has been mapped using high-resolution MRI. The method can be used to explore the distribution of other commonly used nerve blocks in the field of regional anaesthesia. This may help to document the number of injections needed in each regional block as well as the necessary volume of injectate. References None chosen Personal Information Page 8 of 8