Correspondence
Anaesthesia 2015, 70, 361–372
E. Lewis A. Murphy M. P. Chawathe Abertwawe Bro Morgannwg University Health Board, Swansea, UK P. Thomas Medical Safety Management Ltd., UK No external funding and no competing interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com.
References 1. Marshall SD, Mehra R. The effects of a displayed cognitive aid on non-technical skills in a simulated ‘can’t intubate, can’t oxygenate’ crisis. Anaesthesia 2014; 69: 669–77. 2. Fletcher G, Flin R, McGeorge P, Glavin R, Maran N, Patey R. Anaesthetists’ NonTechnical Skills (ANTS): evaluation of a behavioural marker system. British Journal of Anaesthesia 2003; 90: 580–8. 3. Flin R, Patey R. Non-technical skills for anaesthetists: developing and applying ANTS. Best Practice & Research Clinical Anaesthesiology 2011; 25: 215–27. 4. Royal College of Anaesthetists. Curriculum for a CCT in Anesthetics, 2nd Edn, 2010. www.rcoa.ac.uk/documentstore/curriculum-cct-anaesthetics-2010 (accessed 09/12/2014). 5. Graham J, Hocking G, Giles E. Anaesthesia Non-Technical Skills: can anaesthetists be trained to reliably use this behavioural marker system in 1 day? British Journal of Anaesthesia 2010; 104: 440–5. 6. Gingerich A, Regehr G, Eva KW. Raterbased assessments as social judgments: rethinking the etiology of rater errors. Academic Medicine 2011; 86: S1–7. doi:10.1111/anae.13021
Yet more on TAP block nomenclature We read with interest the letter from Hebbard regarding TAP block
nomenclature [1]. We wish to make some comments, hoping to not add confusion to the discussion. The nomenclature regarding TAP block was initially based on topographic descriptions of where to access the block superficially in the abdomen (anterior, posterior, lateral, mid-axillary, subcostal, etc). Over time, nomenclature came to include the deep anatomy of the transverse abdominal plexus, as highlighted by Borglum et al. [2], and also the ‘target’ area of TAP block [2]. We believe that an upper (intercostal) and lower TAP block can be based reasonably on anatomic findings [2, 3] and spread pattern of anaesthetic [2], and that correct nomeclature should be based primarily on these rather than the injection site, particularly as several anatomic studies, together with our own clinical experience with ultrasound, have shown that superficial anatomy does not reflect deep anatomy, which is the ‘target’ of TAP block [3, 4]. For this reason, the ‘upper subcostal TAP block’ defined by Hebbard should be called an ‘upper rectus sheath block’, because it aims to block the rectus sheath plexus. Moreover, the anatomic basis for the classification of the subcostal TAP block into an ‘upper’ and ‘lateral’ TAP block or a ‘medial’ and ‘lateral’ intercostal TAP block, as named by Borglum et al., has to be demonstrated on the basis of anaesthetic spread, nerve involvement and dermatomal anaesthesia [5]. The term ‘ilio-inguinal TAP block’ is acceptable, but only if performed as described by Hebbard because all the other lower TAP block techniques may unreliably block the L1 roots [1].
© 2015 The Association of Anaesthetists of Great Britain and Ireland
Anatomical, imaging and clinical studies show a different pattern of anaesthetic spread, nerve involvement and dermatomal anaesthesia between access sites for TAP block [6]. This is true expecially for lower TAP blocks (mid-axillary, posterior, triangle of Petit, lateral, anterior, classic, etc). For this reason, we think that nomenclature should include a secondary indication of expected block coverage. However, a great variability in anaesthetic spread, nerve involvement and dermatomal anaesthesia is seen after TAP blocks. For example, regardless of the dual technique and a relatively broader area of block after subcostal TAP block [5, 7], efficacy seem to be greater in the lower abdomen [5], with the mean number of affected nerves limited to 3.75 after lower TAP block [8] and 5.5 after upper TAP block [8], corresponding clinically to the mean number of dermatomes blocked [2, 6, 9]. Carney et al. showed also epidural and paravertebral extent of anaesthetic related to some techniques [4]. Deeper knowledge of the spread pattern and the expected area of dermatomal coverage are needed before nomenclature can be modified correctly.
Z. Mokini G. Vitale San Gerardo University Hospital, Monza, Italy Email: [email protected] No external funding and no conflict of interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesiacorrespondence.com. 369
Anaesthesia 2015, 70, 361–372
References 1. Hebbard P. TAP block nomenclature. Anaesthesia 2014; 69: 112–3. 2. Børglum J, Jensen K, Christensen AF, et al. Distribution patterns, dermatomal anesthesia and ropivacaine serum concentrations after bilateral dual transversus abdominis plane block. Regional Anesthesia and Pain Medicine 2012; 37: 294–301. 3. Rozen WM, Tran TM, Ashton MW, Barrington MJ, Ivanusic JJ, Taylor GI. Refining the course of the thoracolumbar nerves: a new understanding of the innervation of the anterior abdominal wall. Clinical Anatomy 2008; 21: 325–33. 4. Jankovic ZB, du Feu FM, McConnell P. An anatomical study of the transversus abdominis plane block: location of the lumbar triangle of Petit and adjacent nerves. Anesthesia and Analgesia 2009; 109: 981–5. 5. Børglum J, Maschmann C, Belhage B, Jensen K. Ultrasound-guided bilateral dual transversus abdominis plane block: a new four-point approach. Acta Anaesthesiologica Scandinavica 2011; 55: 658–63. 6. Carney J, Finnerty O, Rauf J, Bergin D, Laffey JG, McDonnell JG. Studies on the spread of local anaesthetic solution in transversus abdominis plane blocks. Anaesthesia 2011; 66: 1023–30. 7. Lee TH, Barrington MJ, Tran TM, Wong D, Hebbard PD. Comparison of extent of sensory block following posterior and subcostal approaches to ultrasound-guided transversus abdominis plane block. Anaesthesia and Intensive Care 2010; 38: 452–60. 8. Milan Z, Tabor D, McConnell P, Pickering J, Kocarev M, du Feu F, Barton S. Three different approaches to transversus abdominis plane block: a cadaveric study. Medicinski Glasnik 2011; 8: 181–4. 9. Mitchell AU, Torup H, Hansen EG, et al. Effective dermatomal blockade after subcostal transversus abdominis plane block. Danish Medical Journal 2012; 59: A4404. doi:10.1111/anae.13023
Teaching novice anaesthetists An ‘imprecise idea’ about clinical anaesthesia in the general population of healthcare professionals is not just 370
Correspondence
confined to the Indian subcontinent [1]. During the past ten years as an anaesthetic consultant, first in the East Midlands, then the South West of England and now the South West of Scotland, I have found many staff to be vague on the objectives of anaesthesia when asked. A need to be unconscious, unaware or pain-free are the common answers. Whilst worthy objectives, I have never felt that they really get to the heart of the matter or cover all of the many areas anaesthesia is practised. A venerable ophthalmologist, lamenting the rise in popularity of orbital blocks, once challenged me: “The problem is that you anaesthetists don’t give enough **** anaesthetics any more!” I have always felt he was somewhat missing the point of my endeavours. For some years, I too have used the model of patient, surgeon and anaesthetist with their different hypothetical requirements. However, I use this as a vehicle to introduce the ‘triad of anaesthesia’, as a way into discussing the pharmacology of a balanced general anaesthetic. As for the ‘core principles of anaesthesia’, it is my opinion that they can be divided into the following three objectives: i) Preventing psychological trauma: this might simply be holding someone’s hand during surgery under regional blockade, good attention to peri-operative analgesia, or from the oblivion of general anaesthesia. We all strive to calm and reassure our patients, but the recent NAP5 [2] report has
shown how easily psychological trauma can be caused; ii) Preventing unnecessary physical trauma – ‘unnecessary’ as surgery is, by its very nature, a controlled physical trauma. However, most of what we do in anaesthesia removes the many protective mechanisms and reflexes that our patients have spent some 65 million years evolving. So while I can only do so much about where my surgical colleague chooses to cut, I am obliged not to ‘add insult to injury’ in what can be a complex and dangerous envionment; iii) Physiological manipulation to facilitate the technical tasks of surgery, by simply ensuring that the tissue to be operated on does not move too much, by altering the blood flow to an organ, or by allowing access to various body compartments through positioning and relaxation. It is very difficult to sum up what was once called ‘the dark art’ of anaesthesia in any pithy principles, but I too have had good feedback and hope that these might help illuminate some of what we do to the uninitiated. I. Anderson University Hospital Crosshouse, Kilmarnock, UK Email: [email protected] No external funding and no conflict of interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesiacorrespondence.com.
© 2015 The Association of Anaesthetists of Great Britain and Ireland
Anaesthesia 2015, 70, 361–372
E. Lewis A. Murphy M. P. Chawathe Abertwawe Bro Morgannwg University Health Board, Swansea, UK P. Thomas Medical Safety Management Ltd., UK No external funding and no competing interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com.
References 1. Marshall SD, Mehra R. The effects of a displayed cognitive aid on non-technical skills in a simulated ‘can’t intubate, can’t oxygenate’ crisis. Anaesthesia 2014; 69: 669–77. 2. Fletcher G, Flin R, McGeorge P, Glavin R, Maran N, Patey R. Anaesthetists’ NonTechnical Skills (ANTS): evaluation of a behavioural marker system. British Journal of Anaesthesia 2003; 90: 580–8. 3. Flin R, Patey R. Non-technical skills for anaesthetists: developing and applying ANTS. Best Practice & Research Clinical Anaesthesiology 2011; 25: 215–27. 4. Royal College of Anaesthetists. Curriculum for a CCT in Anesthetics, 2nd Edn, 2010. www.rcoa.ac.uk/documentstore/curriculum-cct-anaesthetics-2010 (accessed 09/12/2014). 5. Graham J, Hocking G, Giles E. Anaesthesia Non-Technical Skills: can anaesthetists be trained to reliably use this behavioural marker system in 1 day? British Journal of Anaesthesia 2010; 104: 440–5. 6. Gingerich A, Regehr G, Eva KW. Raterbased assessments as social judgments: rethinking the etiology of rater errors. Academic Medicine 2011; 86: S1–7. doi:10.1111/anae.13021
Yet more on TAP block nomenclature We read with interest the letter from Hebbard regarding TAP block
nomenclature [1]. We wish to make some comments, hoping to not add confusion to the discussion. The nomenclature regarding TAP block was initially based on topographic descriptions of where to access the block superficially in the abdomen (anterior, posterior, lateral, mid-axillary, subcostal, etc). Over time, nomenclature came to include the deep anatomy of the transverse abdominal plexus, as highlighted by Borglum et al. [2], and also the ‘target’ area of TAP block [2]. We believe that an upper (intercostal) and lower TAP block can be based reasonably on anatomic findings [2, 3] and spread pattern of anaesthetic [2], and that correct nomeclature should be based primarily on these rather than the injection site, particularly as several anatomic studies, together with our own clinical experience with ultrasound, have shown that superficial anatomy does not reflect deep anatomy, which is the ‘target’ of TAP block [3, 4]. For this reason, the ‘upper subcostal TAP block’ defined by Hebbard should be called an ‘upper rectus sheath block’, because it aims to block the rectus sheath plexus. Moreover, the anatomic basis for the classification of the subcostal TAP block into an ‘upper’ and ‘lateral’ TAP block or a ‘medial’ and ‘lateral’ intercostal TAP block, as named by Borglum et al., has to be demonstrated on the basis of anaesthetic spread, nerve involvement and dermatomal anaesthesia [5]. The term ‘ilio-inguinal TAP block’ is acceptable, but only if performed as described by Hebbard because all the other lower TAP block techniques may unreliably block the L1 roots [1].
© 2015 The Association of Anaesthetists of Great Britain and Ireland
Anatomical, imaging and clinical studies show a different pattern of anaesthetic spread, nerve involvement and dermatomal anaesthesia between access sites for TAP block [6]. This is true expecially for lower TAP blocks (mid-axillary, posterior, triangle of Petit, lateral, anterior, classic, etc). For this reason, we think that nomenclature should include a secondary indication of expected block coverage. However, a great variability in anaesthetic spread, nerve involvement and dermatomal anaesthesia is seen after TAP blocks. For example, regardless of the dual technique and a relatively broader area of block after subcostal TAP block [5, 7], efficacy seem to be greater in the lower abdomen [5], with the mean number of affected nerves limited to 3.75 after lower TAP block [8] and 5.5 after upper TAP block [8], corresponding clinically to the mean number of dermatomes blocked [2, 6, 9]. Carney et al. showed also epidural and paravertebral extent of anaesthetic related to some techniques [4]. Deeper knowledge of the spread pattern and the expected area of dermatomal coverage are needed before nomenclature can be modified correctly.
Z. Mokini G. Vitale San Gerardo University Hospital, Monza, Italy Email: [email protected] No external funding and no conflict of interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesiacorrespondence.com. 369
Anaesthesia 2015, 70, 361–372
References 1. Hebbard P. TAP block nomenclature. Anaesthesia 2014; 69: 112–3. 2. Børglum J, Jensen K, Christensen AF, et al. Distribution patterns, dermatomal anesthesia and ropivacaine serum concentrations after bilateral dual transversus abdominis plane block. Regional Anesthesia and Pain Medicine 2012; 37: 294–301. 3. Rozen WM, Tran TM, Ashton MW, Barrington MJ, Ivanusic JJ, Taylor GI. Refining the course of the thoracolumbar nerves: a new understanding of the innervation of the anterior abdominal wall. Clinical Anatomy 2008; 21: 325–33. 4. Jankovic ZB, du Feu FM, McConnell P. An anatomical study of the transversus abdominis plane block: location of the lumbar triangle of Petit and adjacent nerves. Anesthesia and Analgesia 2009; 109: 981–5. 5. Børglum J, Maschmann C, Belhage B, Jensen K. Ultrasound-guided bilateral dual transversus abdominis plane block: a new four-point approach. Acta Anaesthesiologica Scandinavica 2011; 55: 658–63. 6. Carney J, Finnerty O, Rauf J, Bergin D, Laffey JG, McDonnell JG. Studies on the spread of local anaesthetic solution in transversus abdominis plane blocks. Anaesthesia 2011; 66: 1023–30. 7. Lee TH, Barrington MJ, Tran TM, Wong D, Hebbard PD. Comparison of extent of sensory block following posterior and subcostal approaches to ultrasound-guided transversus abdominis plane block. Anaesthesia and Intensive Care 2010; 38: 452–60. 8. Milan Z, Tabor D, McConnell P, Pickering J, Kocarev M, du Feu F, Barton S. Three different approaches to transversus abdominis plane block: a cadaveric study. Medicinski Glasnik 2011; 8: 181–4. 9. Mitchell AU, Torup H, Hansen EG, et al. Effective dermatomal blockade after subcostal transversus abdominis plane block. Danish Medical Journal 2012; 59: A4404. doi:10.1111/anae.13023
Teaching novice anaesthetists An ‘imprecise idea’ about clinical anaesthesia in the general population of healthcare professionals is not just 370
Correspondence
confined to the Indian subcontinent [1]. During the past ten years as an anaesthetic consultant, first in the East Midlands, then the South West of England and now the South West of Scotland, I have found many staff to be vague on the objectives of anaesthesia when asked. A need to be unconscious, unaware or pain-free are the common answers. Whilst worthy objectives, I have never felt that they really get to the heart of the matter or cover all of the many areas anaesthesia is practised. A venerable ophthalmologist, lamenting the rise in popularity of orbital blocks, once challenged me: “The problem is that you anaesthetists don’t give enough **** anaesthetics any more!” I have always felt he was somewhat missing the point of my endeavours. For some years, I too have used the model of patient, surgeon and anaesthetist with their different hypothetical requirements. However, I use this as a vehicle to introduce the ‘triad of anaesthesia’, as a way into discussing the pharmacology of a balanced general anaesthetic. As for the ‘core principles of anaesthesia’, it is my opinion that they can be divided into the following three objectives: i) Preventing psychological trauma: this might simply be holding someone’s hand during surgery under regional blockade, good attention to peri-operative analgesia, or from the oblivion of general anaesthesia. We all strive to calm and reassure our patients, but the recent NAP5 [2] report has
shown how easily psychological trauma can be caused; ii) Preventing unnecessary physical trauma – ‘unnecessary’ as surgery is, by its very nature, a controlled physical trauma. However, most of what we do in anaesthesia removes the many protective mechanisms and reflexes that our patients have spent some 65 million years evolving. So while I can only do so much about where my surgical colleague chooses to cut, I am obliged not to ‘add insult to injury’ in what can be a complex and dangerous envionment; iii) Physiological manipulation to facilitate the technical tasks of surgery, by simply ensuring that the tissue to be operated on does not move too much, by altering the blood flow to an organ, or by allowing access to various body compartments through positioning and relaxation. It is very difficult to sum up what was once called ‘the dark art’ of anaesthesia in any pithy principles, but I too have had good feedback and hope that these might help illuminate some of what we do to the uninitiated. I. Anderson University Hospital Crosshouse, Kilmarnock, UK Email: [email protected] No external funding and no conflict of interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesiacorrespondence.com.
© 2015 The Association of Anaesthetists of Great Britain and Ireland
