Issuu on Google+

www.medical-publishing.com

Ultrasound-guided Procedures in Anaesthesiology

RA, A, ESations R S A nd ith nce w recomme a d r o A In accand ISUR M DEGU

Femoral Vein Femoral Artery

Needle (visible)

Needle (hardly visible) Femur Local Anesthetic lateral lat attera erall

Ischiadic Nerve

medial

Thomas Grau - Tim M채cken


Imprint MD, PhD, MA Thomas Grau MD Tim Mäcken

Ultrasound-guided procedures in anaesthesiology Clinic for Anaesthesiology, Intensive Care, Palliative Care & Pain Medicine BG University Hospital Bergmannsheil Bürkle-de-la-Camp Platz 1 44789 Bochum Germany

1st edition 2009 (based on 2nd german edition) ISBN 978-3-941-022096 - www.medical-publishing.com Herrenweg 46 - 69151 Neckargemünd - Tel 0160-6888266 Fax 0231-5438 2631 ultraschall@medical-publishing.com Planning: Thomas Grau, Tim Mäcken Layout: Nicole Altenbeck, Tim Mäcken Editing: Nicole Altenbeck, Stefanie Fatehi Illustrations: Thomas Grau Graphs and tables: Nicole Altenbeck, Thomas Grau, Tim Mäcken Print: Advantage Printpool GmbH, Gilching Sales: www.medical-publishing.com - Publisher, Neckargemünd

This publication is copyrighted. All rights reserved by the publisher, www.medical-publishing.com, Neckargemünd, in particular the right of translation, reprinting, retrieval of figures and tables, media reproduction and storage in a retrieval system of any parts of this publication. Reproduction of the publication or any parts thereof is subject to the provisions of the most current copyright law of the Federal Republic of Germany. Any use is subject to royalty payment. Violations of these provisions are subject to the legal sanctions of the German Copyright Law. Product liability: The publisher assumes no responsibility for instructions concerning the implementation of procedures, techniques and applications - or for those referring to drug administration and dosage. The specifications made within this publication are in line with the current research in this field and present our actual treatment concept. The user should assess the appropriateness of individual procedures by referring to other literature sources. The use of product names and designations without specific trademark references should not lead the reader to assume these names may be used freely, as specified in trademark protection provisions.


Preface

The technique of applying ultrasound in anaesthesiology arouses much interest. This is reflected in the notable increase in scientific publications on ultrasound-guided peripheral nerve blocks. In this publication, we would also like to direct the readerʝs attention to the benefits of using ultrasound technology for vascular punctures and central nerve blocks. The chapters on scanning and puncture techniques as well as training and compensation settlement round off our appraisal of ultrasound-guided punctures in anaesthesiology. The book has been purposely written in a clinical and practice-oriented manner. Representations of original ultrasound scans - often with the relevant structures traced for enhancement - together with photos from clinical practice, offer easy to follow guidelines for ultrasound-guided punctures. We wish you enjoyable reading with this book. Thomas Grau & Tim Mäcken


.


Editorial From all disciplines, it is actually quite astonishing that it took so long for ultrasound to become an accepted routine method in anaesthesiology. For decades, we anaesthetists have watched neighbouring disciplines, such as obstetrics, orthopaedics, surgery, urology and cardiology, apply ultrasound in their clinical practice. Yet not even the fact that this technology was used in intensive care wards for many years moved us to give this technology a trial within the administration of nerve blocks - despite the fact that these procedures were not always successful. The first papers, written in the late 1970‘s, appraised Doppler technology as an indirect method to support plexus blocks [1]. As late as 1983, authors still described a plexus block method by which the block was carried out after surgical preparation of the plexus [2]. The subsequent period was characterised by increased prevalence of nerve stimulation techniques. It was only in 1992 that the first paper on „sonography assisted brachial plexus anaesthesia“ was published. This paper, which unfortunately was not submitted by an anaesthesia clinic, but by the Surgical University Hospital of Heidelberg, describes a method by which ultrasound is not applied for nerve identification, but simply to

identify the vessels in the neurovascular bundle [3]. This paper was largely ignored - and was only cited twice. Due to ultrasound applications, regional anaesthesia has recently gained in appeal and prevalence. Ultrasound allows for more carefull procedure implementation. There is no need for electric nerve stimulation. The direct visualisation enables clear identification of nerve and needle. Distribution of the local anaesthetic is made visible. Success rates can be notably increased. Onset times are notably reduced. Ultrasound has now become a routine application. The author team of the present book has played an instrumental role in this development. Priv. Doz. Dr. Grau, in particular, has made this method accessible to many colleagues through numerous congresses and workshops and has continuously worked on perfecting the method. This second book, written in collaboration with Dr. Mäcken, offers a comprehensive and instructive overview of the various ultrasound application techniques in anaesthesiology. I wish this book and the methods described therein the success that they deserve on

account of their positive effect on patient safety and effectivity. However, no book alone can convey the necessary manual skills, which is why the motto after reading this book must be: practice - practice - practice. Michael Zenz Bochum

[1] La Grange P, Forster PA, Pretorius LK. Application of the Doppler ultrasound bloodflow detector in supraclavicular brachial plexus block. Br J Anaesth 1978 Sept;50(9):965-7. [2] Tonczar L, Illias W, Mayrhofer O, Munk P, Sandbach G. An unusual procedure in performing brachial plexus block. Arch Orthop Trauma Surg 1983;101(4):297-9. [3] Friedl W, Fritz T. Ultrasound assisted brachial plexus anesthesia. Chirurg 1992 Sept;63(9):759-60.


Table of contents 1 Ultrasound Systems and Puncture Techniques 1.1. 1.2. 1.3. 1.4. 1.5. 1.6. 1.7. 1.8. 1.9. 1.9.1. 1.9.2. 1.9.3. 1.9.4.

1

Ultrasound system development..................................................1 Description of systems ................................................................1 Operating the ultrasound system ................................................5 Doppler settings...........................................................................6 Coupling media.............................................................................6 Cleaning and disinfection ............................................................6 Ultrasound probes .......................................................................8 Basic physical principles ........................................................... 10 Imaging techniques ................................................................... 13 Puncture techniques........................................................... 13 Transducer movements ...................................................... 17 Ultrasound probe covers.................................................... 18 Standard puncture procedure ............................................ 21

2 Vascular Punctures using Ultrasound Guidance 24 2.1. 2.2. 2.3. 2.4. 2.5. 2.6. 2.6.1. 2.7. 2.7.1. 2.7.2. 2.7.3. 2.7.4. 2.7.5. 2.7.6.

Introduction............................................................................... 24 Principles of vascular puncture ................................................ 25 Visualisation of blood vessels using ultrasound ....................... 26 Blood vessel scan and puncture planes ................................... 26 Doppler settings........................................................................ 28 Indications for the use of ultrasound ....................................... 29 Flow diagram for CVC placements ...................................... 29 Special vascular accesses ........................................................ 31 V. jugularis interna ............................................................. 31 „Notch“ puncture (v. brachiocephalica)............................. 35 V. subclavia ........................................................................ 36 V. femoralis ......................................................................... 39 V. basilica / cephalica ........................................................ 40 Peripheral veins.................................................................. 40

2.7.7. 2.7.8. 2.7.9. 2.7.10. 2.8.

Distal puncture of the a. radialis ........................................ 40 Proximal puncture of the a. radialis .................................. 42 A. axillaris .......................................................................... 44 A. femoralis ....................................................................... 45 Literature .................................................................................. 46

3 Peripheral Nerve Blocks 3.1. 3.2. 3.2.1. 3.2.2. 3.2.3. 3.2.4. 3.3. 3.3.1. 3.3.2. 3.4. 3.5. 3.6. 3.6.1. 3.6.2. 3.6.3. 3.6.4. 3.7. 3.8. 3.9. 3.10. 3.11. 3.12. 3.12.1. 3.12.2.

48

Introduction............................................................................... 48 Causes of insufficient block success ......................................... 48 Anatomical causes .............................................................. 48 Methodical causes .............................................................. 49 Training and application ..................................................... 50 Is imaging technology a solution?...................................... 50 Visualisation of nerves ............................................................. 50 Peripheral nerves in ultrasound scans .............................. 51 Needle visualisation ............................................................ 53 Drugs and nerve interactions ................................................... 54 Is ultrasound visualisation combined with nerve stimulation useful?.... 60 Special block techniques ........................................................... 63 Interscalene brachial plexus block ..................................... 63 Supraclavicular brachialplexus block.................................. 67 Infraclavicular brachial plexus block................................... 70 Axillary brachial plexus block ............................................. 75 N. femoralis ............................................................................... 79 N. saphenus .............................................................................. 82 N. cutaneus femoris lateralis .................................................... 84 N. obturatorius .......................................................................... 84 N. ilioinguinalis and iliohypogastricus ....................................... 86 Proximal n. ischiadicus block ................................................... 88 Access from anterior ......................................................... 88 Access from posterior (subgluteal block) ......................... 91


Table of contents 3.12.3. 3.13. 3.13.1. 3.13.1. 3.13.2. 3.13.3. 3.13.4. 3.13.5. 3.14. 3.15.

Distal n. ischiadicus block (Knee block) ............................. 93 Rescue blocks ........................................................................... 96 N. medianus........................................................................ 96 N. ulnaris ............................................................................ 99 N. radialis ......................................................................... 100 N. musculocutaneus ......................................................... 102 N. peronaeus profundus .................................................. 102 N. tibialis ........................................................................... 104 Postoperative dose schedule.................................................. 104 Literature ................................................................................ 106

4 Neuraxial Blocks 4.1. 4.2. 4.3. 4.4. 4.5. 4.6. 4.7. 4.8. 4.9. 4.10.

5 Training and DEGUM Quality Concept 5.1. 5.2. 5.2.1. 5.2.2. 5.2.3. 5.2.4.

109

Principles of theultrasound examination ................................ 109 Offline technique .................................................................... 109 Online technique ..................................................................... 112 Punctures in the thoracic region ........................................... 116 Clinical studies......................................................................... 119 Training ................................................................................... 119 Pregnancy-caused effects ...................................................... 120 Clinical areas of application .................................................... 121 Summary ................................................................................. 122 Literature ................................................................................ 125

126

DEGUM .................................................................................... 126 Introduction to the Staged Training Scheme .......................... 126 Quality system Certificate in Anaesthesiology .................. 126 DEGUM Level I .................................................................. 126 DEGUM Level II ................................................................. 128 DEGUM Trainer and DEGUM Seminar Leader ................... 129

5.2.5. 5.2.6. 5.2.7. 5.3. 5.3.1. 5.4. 5.4.1. 5.4.2. 5.4.3. 5.4.4. 5.5. 5.6.

DEGUM Course Leader ..................................................... 129 DEGUM Level III ................................................................ 131 Areas of application ......................................................... 131 Systems classification and categorisation............................... 131 Services Catalogue and compensation settlement........... 131 Training ................................................................................... 133 Theory .............................................................................. 133 Practice ............................................................................ 135 Application on patients ..................................................... 138 Blocks and punctures on patients.................................... 139 Summary ................................................................................. 140 Literature ................................................................................ 142

6 Ultrasound Puncture Workplace 6.1. 6.2. 6.3. 6.4. 6.5. 6.6. 6.7.

143

Positioning and layout sketches.............................................. 143 Interscalene ............................................................................ 144 Supraclavicular ........................................................................ 146 Infraclavicular .......................................................................... 148 Axillary..................................................................................... 152 N. femoralis ............................................................................. 154 N. ischiadicus (distal).............................................................. 156


.


Introduction to Ultrasound Systems 1 1.1.

The reduction in size and enhanced portability of ultrasound systems constitutes a further advantage of these recent development (figure 1.1). The lighter, portable systems allow for straightforward patient examinations in less spacious situations such as in preparation rooms and intensive care units. Despite the sensitive electronic technology and increased portability, today‘s machines are actually less prone to defects.

Ultrasound system development

Over the last years, ultrasound system technology has improved significantly. The machines used for examinations and studies some years ago were heavy, largely immobile and complicated to operate. These early ultrasound systems had a noticeable performance limit. The machines were either unable or only partially able to visualise finer tissue structures. Current systems using high resolution probes (10-18 MHz) significantly enhance imaging capacities and options. These technological developments have made so-called ‚small parts ultrasound‘ possible. This entails the imaging of very fine structures - such as nerves - in adequate quality. The newer generation systems actuate the piezoelectric crystals much more effectively. The machines are no longer only able to transmit and receive longitudinal sound waves - but can now process plane and traverse waves as well. Manufacturers have given various names to this technology (cross-beam, multi-beam etc.). The thus received data is collated and displayed as an image. This results in a notable reduction of artefact formation - and in improved visualisation of structures which were hitherto difficult to depict.

Their high performance capacity enables application in various areas. Sometimes, simply exchanging the probe or installing new software (modules) can notably enhance the range of clinical applications. This enhanced range includes cardiological or abdominal examinations as well as small parts ultrasound for nerve blocks. 1.2.

Figure 1.1 MyLab 25XV Gold by Esaote® on a transport trolley with printer, battery and various probes. Further information at: http://www.esaote.com/

Description of systems

In order to carry out ultrasound-guided nerve blocks, one requires basic knowledge of the machines used (e.g. operation and maintenance) and of the physical properties of sound waves, their propagation in tissue - and especially the occurrence and interpretation of artefacts. The following are images of current ultrasound 1


1 Ultrasound Systems 1

2

3

4 5

6

7

8 9 10

11

12

26 13 14 15

25

16

17

18

19 20 21

22

23

24

Figure 1.3 Schematic MyLab Five® key/function overview. Image by courtesy of Esaote®, Cologne, Germany. 1. 2. 3. 4. 5. 6. 7.

Figure 1.2 MyLab Five®, a modular ultrasound system by Esaote® on a transport trolley with three different probes. Further information at: http://www.esaote.com/

2

8. 9. 10. 11. 12. 13. 14.

Start/conclude examination Select probe defaults (preset) Pulsed-wave Doppler On/Off Adjust transducer frequency Access to patient/examination database Redisplay current examination Operate sound beam direction in B-Mode, Colour and Doppler Mode (tilt) Viewing options of measurements made Depth: Adjust depth of penetration Switch to B-Mode Gain: Gain settings Power: Transmitter intensity settings CW Doppler (continuous Doppler) On/Off Gain CFM: Amplify ultrasound signals in CW, PW or

15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26.

Colour Doppler Mode Colour Flow Mode (Colour Doppler) On/Off Activate pictogram display Activate „Special Measurements“ display Activate measurement curser for basic measurements (length, distance etc.) Pointer: Activate pointer/cursor Switch to dual view of two images Depending on specific mode: Shift focus, Optimise colour window Set row cursor before M-Mode is started Zoom On/Off Save image or image series Search for peripheral equipment (e.g. printer) Toggle switch function varies according to current mode


Ultrasound Systems 1

1 10 11 2

5 3

6

4

7

8 9

Figure 1.5 Schematic key/function overview of LOGIQ e速. Image by courtesy of GE速 Healthcare, Munich, Germany

Figure 1.4 LOGIQ速 e: High resolution, portable ultrasound system by General Electric速 (GE) on a transport trolley with various transducers and a printer. Further information at: http://www.gehealthcare.com/worldwide.html

1. 2. 3. 4. 5. 6.

On/Off: Switch machine on and off TGC: Depth-dependant gain (time gain control) Patient: Enter new patient data record Mode, amplitude and automatic keys: M-Mode (M), Pulse Waved Doppler (PW), Colour Doppler (CF) and B-Mode (B) Imaging/Measuring keys Cursor, delete, body marking, M/D cursor, scanning region, Set/B Pause Depth, zoom, ellipse

7. 8. 9. 10. 11.

Programmable keys: e.g. save, print, export Freeze: Stops the sequence Start/Stop Focus: Number of focal zones, focal position Frequency

3


1 Ultrasound Systems

Figure 1.6 Schematic key/function overview of M-Turbo®. Schematic key/function overview of SonoSite®, Erlangen, Germany. 1. 2. 3. 4. 5. 6. 7. 8.

4

On/Off: Switch system on or off. Text: Activate or deactivate keyboard for data entry. Picto: Switch pictograms on or off. Zoom: Enlarge image by factor 2. Depth: Depth adjustment settings (increase or decrease). Near gain, distant gain: Gain adjustment (near, distant, total). Autogain: Automatic Gain adjustment. Enter: Enter/Confirmation key or mouse button.

In Colour Doppler Mode: Toggle between „Drag Window“ and „Adjust Window Size“ modes. In Doppler Mode: Toggle between „Drag Target Window“ and „Alter Angle Correction“. In Measurement Mode: Toggle between two measurement points. 9. Measure: Activate measurement. 10. Calc: Activate/Deactivate calculation menu. 11. Freeze: Freeze image recording. 12. Display screen menus and corresponding keys.

Figure 1.7 M-Turbo® Ultrasound System by SonoSite® - modular, portable and high-resolution. Further information at: www.sonosite.com 13. Access to system set-up, patient report, saved images and patient / data entry mask. 14. Exam: Selection of examination images. 15. Programmable keys. 16. Programmable keys. 17. Toggling view options: Dual mode (left <-> right image), Doppler (frequency spectrum <-> B-ImageWindow), M-Mode (M-Mode-Curve <-> B-ImageWindow).


Ultrasound Systems 1

Notice: The Instruction Manual should always be at hand and near the ultrasound examination workstation. One option is to store pdf versions of the instructions on the workstation computer. These could also be regularly distributed as CDs during device introduction sessions (introductions pursuant to MPG) [Medical Devices Act].

Esaote速 MyLab Five Figures 1.10 and 1.11

General Electric速 LOGIQ e Figures 1.12 and 1.13

SonoSite速 M-Turbo Figures 1.14 and 1.15

Linear transducer: LA523

Linear transducer: 12 LRS

Linear transducer: HFL38x

Resolution: Dynamic 7.5-12 MHz: 10

Resolution: 5-13 MHz

Resolution: 6-13 MHz GEN if applicable, PENfor femoral vessels

Operator preset: Nerves 2 - or vascular

Operator preset: neuro 2 (separate preset)

Doppler scale: cm/s

Video standard: PAL, NTSCvia S-VHS

Video standard: VGA, PAL

Video type: PALor NTSC via S-VHS

Table 1.1 Default settings and suitable transducers from 3 portable ultrasound machines.

systems from three manufacturers. They are modular, versatile, quickly deployable and suitable for all types of anaesthetic procedures - provided they are fitted with the appropriate probe(s) (cf. section 1.7). Moreover, this chapter will offer information and guidance regarding ultrasound probe and needle guidance - as well as standard puncture procedures. All machines have configurable default settings ( presets, Table 1.1). These presets constitute optimised settings. Well-experienced operators with sound knowledge of ultrasound technology may gain additional benefit from temporarily adjusting the pre-

sets. However, the machine should be reset after use for the benefit of subsequent, less experienced operators. The systems are able to store sonograms - which can be very valuable for documentation or teaching purposes. Table 1.1 presents an overview of the key presets.

1.3.

Operating the ultrasound system

Needless to say, one must handle highly sensitive microelectronic machines with care. This means: when re-locating the system, bumps and knocks must be avoided, do not twist or kink the probe cable and do not tug or pull on the cable at the power connection. The ultrasound probes in particular, must be handled with care. If the probes fall to the ground due to careless storage or handling this may cause malfunctions. In order to ensure that the system software is not compromised, the machine should always be correctly switched on and off, as specified in the respective instructions. 5


1 Coupling Medium 1.4.

Doppler settings

The use of colour-coded Doppler imaging can be beneficial when carrying out vessel ultrasound scans (Table 1.2). A potential problem with the use of Doppler probes is that they use lower sound frequencies in order to depict blood flow - thus reducing resolution intensity. In doppler applications, the colour red generally signifies flow towards the ultrasound probe and the colour blue generally signifies flow away from the ultrasound probe. This setting can be altered using the machine setup keys. From a technological perspective, one distinguishes between colour Doppler and PW (pulsed-wave) Doppler imaging. CW (continuous wave) Doppler presents a combination of both measurement techniques. 1.5.

Coupling media

Air is the worst possible transmission medium. It is therefore necessary to ensure perfect acoustic coupling between ultrasound probe and cover - as well as between cover and skin. This coupling between transducer and skin enhances sound wave transmission. 6

SonoSite® M-Turbo

Esaote® MyLab Five

General Electric® LOGIQ e

DCP and DCPD keys press "color"

Switch on: "CFM" key (colour flow mode)

Press CF key to switch machine on

To adjust the steering (angle adjustment)

To adjust the beam angle

To adjust the beam angle

Adjust gain (increased or decreased) using the control dial at the bottom left corner of the control panel.

Adjust gain using the flat control dial on the left hand side.

Adjust the colour signal using the "Gain" control dial on the left.

Target: highly visible and low-noise signal Table 1.2 Settings for Doppler application.

Bubble-free ultrasound scanning gel is generally applied between probe and cover. Table 1.3 presents an overview of agents applied to enhance coupling between cover and skin for various media. Section 1.9.3 presents different ultrasound probe cover techniques. Due to the fact that ultrasound gels contain preservatives, aromas and stabilisers, the neurotoxicity of which is unknown, it is mandatory to ensure the highest level of sterility during ultrasound procedures. Avoid introducing ultrasound contact gel under the skin. Disinfectant solutions must not be ‚carried‘ to nerves through the puncture path due to their potential neurotoxicity. We per-

ceive sterile NaCl or local anaesthetic agents to be very safe couplants. Moreover, local anaesthetic agents are bactericidal. The disadvantage of NaCl and local anaesthetic agents compared to contact gel is reduced lubrication properties. 1.6.

Cleaning and disinfection

It goes without saying, that the ultrasound machine must be treated with care and kept as clean as possible. The microelectronic components of the transducers are particularly sensitive. It is therefore mandatory to include these machines in the hospital hygiene plans - and


Cleaning the System 1 to disinfect them before ultrasound-guided punctures are carried out. The ultrasound machine must be switched off before it is cleaned and disinfected to avoid short circuits. The ultrasound system must be unplugged when the system surfaces are cleaned. The transducer probe is waterproof up to where the transducer cable connects with the system unit. Avoid spraying or moistening the control panel and the connectors (transducer cable, battery compartment, docking station). The display screen may only be cleaned using a cloth dampened in a diluted ammonia or alcohol solution (Table 1.4). System surfaces: First wipe the surfaces using a cloth dampened with a mild soap solution to remove larger particles or bodily fluids. Subsequently apply the disinfectant solution to a cloth (not to the machine!) and wipe the surfaces again (see manufacturer instructions for contact times).

Agent

Contact agent (sterile)

Costs

Properties / Disadvantages

Sterile ultrasound gel

++

Expensive

Excellent coupling properties, additives and preservatives in gel may enter body during puncture and may be transported to the nerve(s) - effects unclear (neurotoxic?)

Instillagel®

++

Inexpensive

Excellent contact. Additives and preservatives in gel Risk: see ultrasound gel.

Isopropanol (Skin disinfection solution)

(+)

Inexpensive

Evaporates quickly. Not approved for transducers. Inhibits transducer movement. Solvent may interact with cover or sterile Tegaderm® plaster and impede visibility. Must not reach nerve due to its neurotoxicity.

Sodium chloride solution

++

Inexpensive

Better coupling properties than isopropanol, but not as good a lubricant as gel, no interaction with sterile cover. No interaction

Localanaesthetic

++

Inexpensive

Better coupling properties than isopropanol, but greatly inhibits transducer movement. Interaction with Tegaderm® is notably less severe than between alcohol and Tegaderm.

Table 1.3 Übersicht und Charakteristika einiger Substanzen, die zur Kopplung von Ultraschallwellen verwendet

werden.

Transducer and transducer cable: Remove larger particles and bodily fluids using a cloth dampened with water or a mild soap solution. Subsequently wipe down with moist cloth - then dry. Now spray the 7


Ultrasound guided Procedures in Anaesthesiology