- Email: [email protected]
Evaluation of artery and vein differentiation methods using ultrasound imaging among medical students
832 |
Correspondence
Declaration of interest None declared.
epidural spread in standard- vs low-volume ultrasoundguided interscalene plexus block using contrast magnetic resonance imaging: a randomized, controlled trial. Br J Anaesth 2016; 116: 405–12 2. Mian A, Chaudhry I, Huang R, Rizk E, Tubbs RS, Loukas M. Brachial plexus anesthesia: a review of the relevant anatomy, complications, and anatomical variations. Clin Anat 2014; 27: 210–21 3. Conroy PH, Awad IT. Ultrasound-guided blocks for shoulder surgery. Curr Opin Anaesthesiol 2011; 24: 638–43 4. Verelst P, van Zundert A. Respiratory impact of analgesic strategies for shoulder surgery. Reg Anesth Pain Med 2013; 38: 50–53 5. Bergmann L, Martini S, Kesselmeier M, et al. Phrenic nerve block caused by interscalene brachial plexus block: breathing effects of different sites of injection. BMC Anesthesiol 2016; 16: 45 6. Aszmann OC, Dellon AL, Birely BT, McFarland EG. Innervation of the human shoulder joint and its implications for surgery. Clin Orthop Relat Res 1996; 330: 202–7 7. Dhir S, Sondekoppam RV, Sharma R, Ganapathy S, Athwal GS. A comparison of combined suprascapular and axillary nerve blocks to interscalene nerve block for analgesia in arthroscopic shoulder surgery: an equivalence study. Reg Anesth Pain Med 2016; 41: 564–71 8. Panero AJ, Hirahara AM. A guide to ultrasound of the shoulder, part 2: the diagnostic evaluation. Am J Orthop (Belle Mead NJ) 2016; 45: 233–38 9. Battaglia PJ, Haun DW, Dooley K, Kettner NW. Sonographic measurement of the normal suprascapular nerve and omohyoid muscle. Man Ther 2014; 19: 165–68 10. Lee JJ, Hwang JT, Kim DY, et al. Effects of arthroscopyguided suprascapular nerve block combined with ultrasound-guided interscalene brachial plexus block for arthroscopic rotator cuff repair: a randomized controlled trial. Knee Surg Sports Traumatol Arthrosc Advance Access published on June 16, 2016, doi: 10.1007/s00167-016-4198-7
References 1.
Stundner O, Meissnitzer M, Brummett CM, et al. Comparison of tissue distribution, phrenic nerve involvement, and
doi: 10.1093/bja/aew370
Evaluation of artery and vein differentiation methods using ultrasound imaging among medical students N. Komasawa*, R. Mihara, K. Hattori, T. Minami Osaka, Japan *E-mail:[email protected]
Editor—Central venous catheters (CVCs) provide vascular access for fluid resuscitation, drugs, and antibiotics and allow haemodynamic monitoring and cardiac pacing. Central venous catheters also help to achieve higher peak drug concentrations and shorter circulation times compared with peripheral venous administration. Recently, the ultrasound-guided CVC (US-CVC) technique has become available, which allows differentiation between veins and arteries and improves CVC safety with a visible guidewire to facilitate catheter progression.1 However, novices and medical students with less experience may
find it difficult to distinguish between veins and arteries, which is the first important step. Here, we conducted a survey on the subjective difficulty of ultrasound-based methods to distinguish between veins and arteries among medical students. Ethical approval was deemed unnecessary by the Research Ethics Committee of Osaka Medical College. From December 2015 to February 2016, we conducted a questionnaire survey of 31 fifth year medical students who had no experience with internal jugular vein ultrasound imaging as a part of their routine training at Osaka Medical College. At our institution, we teach
Downloaded from http://bja.oxfordjournals.org/ at Eccles Health Sci Lib-Serials on December 12, 2016
addition to this, PECS-1 block (depositing local anaesthetic between pectoralis major and minor) can be combined to block the lateral pectoral nerve in the same probe position if the acromioclavicular joint is being operated upon concomitantly. For the sub-omohyoid block, the same linear high-frequency (6–13 MHz) ultrasound probe is placed over the supraclavicular fossa to identify the subclavian artery, brachial plexus and the inferior belly of the omohyoid muscle (Fig. 1C). Using an in-plane lateralto-medial needle approach, 5 ml of the local anaesthetic solution (ropivacaine 0.5%) is deposited above the clavicle, under the inferior belly of omohyoid, to cover the suprascapular nerve (Fig. 1C). This fascial plane between the inferior belly of omohyoid and the strap muscles of the neck is closely related to the suprascapular nerve along its course until the suprascapular notch. Viewing of easily identifiable structures, such as the bony landmarks and muscle layers around the shoulder joint, should make this technique feasible even by novices compared with peripheral nerve blocks. We have been using this technique for analgesia in patients with respiratory disease undergoing shoulder surgery along with ultrasound assessment of diaphragmatic function at our institute after preliminary anatomical studies of injectate spread in fresh cadavers were promising. Additionally, as these intermuscular planes can be appreciated arthroscopically, the performance of this technique may even be feasible by the surgeons using conventional or liposomal formulations of local anaesthetics.10 Combined subscapularis plane and sub-omohyoid injections may serve as an alternative to peripheral nerve blocks for shoulder analgesia, with minimal impact on phrenic nerve function. Further well-designed randomized studies are required to evaluate this method in comparison to other analgesic modalities.
Correspondence | 833
100
Visual analog scale (mm)
90
#
80 70
*
60 50 40 30 20 10 Pulse
Colour Doppler Compression
Valsalva
Fig 1 Comparison of the four methods (pulse, colour Doppler, compression, and Valsalva methods) to differentiate between the common carotid artery and the internal jugular vein.
Declaration of interest None declared. artery (common carotid artery) and vein (internal jugular vein) differentiation in healthy volunteers using an ultrasound system with a 5–10 MHz transducer (iLookTM; SonoSite, Inc., Bothell, WA, USA). We introduced the following four differentiation methods: arterial pulse (pulse), colour Doppler, compression (vein reduction), and Valsalva (vein expansion) methods. At the end of training, participants rated the difficulty of the four methods on a visual analog scale, which ranged from 0 (extremely easy) to 100 mm (extremely difficult).2 Results obtained from each trial were compared using one-way repeated measures analysis of variance. A value of P < 0.05 was considered statistically significant.
References 1. Tokumine J, Lefor AT, Yonei A, Kagaya A, Iwasaki K, Fukuda Y. Three-step method for ultrasound-guided central vein catheterization. Br J Anaesth 2013; 110: 368–73 2. Komasawa N, Mihara R, Fujiwara S, Minami T. Significance of basic airway management simulation training for medical students. J Clin Anesth 2016; 32: 29
doi: 10.1093/bja/aew371
Unusual position of J-guide wire during ultrasound-guided subclavian vein catheterization T. Saranteas*, I. Koliantzaki Athens, Greece *E-mail: [email protected]
Editor—We conducted a retrospective analysis of all the ultrasound-guided catheterizations in which unusual J-guide wire atypical positions had been identified. The protocol included ultrasound, long-axis viewing of the J-guide wire,1 2 always before dilatation of the axillary/subclavian vein. The catheterization of the subclavian veins was performed according to the technique of Fragou and colleagues.1 All ultrasound-guided venous catheterizations were performed by a competent consultant anaesthetist with great experience in this technique. Manual ultrasound examinations were conducted using a high-frequency, linear transducer on a portable ultrasound unit (CX 50, Phillips Healthcare, The Netherlands; or Vivid I, GE Healthcare, Waukesha, WI, USA).
The central venous catheterizations took place on patients in the postoperative acute care unit, operating theatres, and the cardiothoracic care unit. Owing to the retrospective design of the study, formal research ethics committee approval and patients’ written informed consent for publication of this manuscript and accompanying images were deemed unnecessary. According to our results, throughout a 70 month period, 220 subclavian ultrasound-guided catheterizations were conducted, and all the potential complications were recorded in our archives. The J-guide wire was clearly seen in 220 out of 220 (100%) patients. In 13 out of 220 (5.9%) subclavian vein catheterizations, unusual J-wire positions in the lumen of the subclavian vein were acknowledged. Unusual positions of the J-wire included the
Downloaded from http://bja.oxfordjournals.org/ at Eccles Health Sci Lib-Serials on December 12, 2016
0
The subjective difficulty of each differentiation method is shown in Fig. 1. There was no significant difference in subjective difficulty between pulse and colour Doppler methods (P ¼ 0.99). The compression method was easier than colour Doppler and pulse methods (P < 0.001 each). The Valsalva method was less difficult compared with the other three (P < 0.001 vs pulse or colour Doppler). Differentiation between the internal jugular vein and the common carotid artery is the first and most important step in US-CVC. According to our survey, medical students found arterial pulse and colour Doppler methods more difficult than other ultrasound image-based methods. This might be associated with the fact that the vein often shows pulsatory motion with artery, and colour Doppler also captures venous flow. In contrast, vein collapse by the compression method and vein enlargement by the Valsalva method were considered relatively easy even for novices. A combination of the compression and Valsalva methods may be effective for novice doctors to differentiate between the internal jugular vein and the common carotid artery on ultrasound images.
Correspondence
Declaration of interest None declared.
epidural spread in standard- vs low-volume ultrasoundguided interscalene plexus block using contrast magnetic resonance imaging: a randomized, controlled trial. Br J Anaesth 2016; 116: 405–12 2. Mian A, Chaudhry I, Huang R, Rizk E, Tubbs RS, Loukas M. Brachial plexus anesthesia: a review of the relevant anatomy, complications, and anatomical variations. Clin Anat 2014; 27: 210–21 3. Conroy PH, Awad IT. Ultrasound-guided blocks for shoulder surgery. Curr Opin Anaesthesiol 2011; 24: 638–43 4. Verelst P, van Zundert A. Respiratory impact of analgesic strategies for shoulder surgery. Reg Anesth Pain Med 2013; 38: 50–53 5. Bergmann L, Martini S, Kesselmeier M, et al. Phrenic nerve block caused by interscalene brachial plexus block: breathing effects of different sites of injection. BMC Anesthesiol 2016; 16: 45 6. Aszmann OC, Dellon AL, Birely BT, McFarland EG. Innervation of the human shoulder joint and its implications for surgery. Clin Orthop Relat Res 1996; 330: 202–7 7. Dhir S, Sondekoppam RV, Sharma R, Ganapathy S, Athwal GS. A comparison of combined suprascapular and axillary nerve blocks to interscalene nerve block for analgesia in arthroscopic shoulder surgery: an equivalence study. Reg Anesth Pain Med 2016; 41: 564–71 8. Panero AJ, Hirahara AM. A guide to ultrasound of the shoulder, part 2: the diagnostic evaluation. Am J Orthop (Belle Mead NJ) 2016; 45: 233–38 9. Battaglia PJ, Haun DW, Dooley K, Kettner NW. Sonographic measurement of the normal suprascapular nerve and omohyoid muscle. Man Ther 2014; 19: 165–68 10. Lee JJ, Hwang JT, Kim DY, et al. Effects of arthroscopyguided suprascapular nerve block combined with ultrasound-guided interscalene brachial plexus block for arthroscopic rotator cuff repair: a randomized controlled trial. Knee Surg Sports Traumatol Arthrosc Advance Access published on June 16, 2016, doi: 10.1007/s00167-016-4198-7
References 1.
Stundner O, Meissnitzer M, Brummett CM, et al. Comparison of tissue distribution, phrenic nerve involvement, and
doi: 10.1093/bja/aew370
Evaluation of artery and vein differentiation methods using ultrasound imaging among medical students N. Komasawa*, R. Mihara, K. Hattori, T. Minami Osaka, Japan *E-mail:[email protected]
Editor—Central venous catheters (CVCs) provide vascular access for fluid resuscitation, drugs, and antibiotics and allow haemodynamic monitoring and cardiac pacing. Central venous catheters also help to achieve higher peak drug concentrations and shorter circulation times compared with peripheral venous administration. Recently, the ultrasound-guided CVC (US-CVC) technique has become available, which allows differentiation between veins and arteries and improves CVC safety with a visible guidewire to facilitate catheter progression.1 However, novices and medical students with less experience may
find it difficult to distinguish between veins and arteries, which is the first important step. Here, we conducted a survey on the subjective difficulty of ultrasound-based methods to distinguish between veins and arteries among medical students. Ethical approval was deemed unnecessary by the Research Ethics Committee of Osaka Medical College. From December 2015 to February 2016, we conducted a questionnaire survey of 31 fifth year medical students who had no experience with internal jugular vein ultrasound imaging as a part of their routine training at Osaka Medical College. At our institution, we teach
Downloaded from http://bja.oxfordjournals.org/ at Eccles Health Sci Lib-Serials on December 12, 2016
addition to this, PECS-1 block (depositing local anaesthetic between pectoralis major and minor) can be combined to block the lateral pectoral nerve in the same probe position if the acromioclavicular joint is being operated upon concomitantly. For the sub-omohyoid block, the same linear high-frequency (6–13 MHz) ultrasound probe is placed over the supraclavicular fossa to identify the subclavian artery, brachial plexus and the inferior belly of the omohyoid muscle (Fig. 1C). Using an in-plane lateralto-medial needle approach, 5 ml of the local anaesthetic solution (ropivacaine 0.5%) is deposited above the clavicle, under the inferior belly of omohyoid, to cover the suprascapular nerve (Fig. 1C). This fascial plane between the inferior belly of omohyoid and the strap muscles of the neck is closely related to the suprascapular nerve along its course until the suprascapular notch. Viewing of easily identifiable structures, such as the bony landmarks and muscle layers around the shoulder joint, should make this technique feasible even by novices compared with peripheral nerve blocks. We have been using this technique for analgesia in patients with respiratory disease undergoing shoulder surgery along with ultrasound assessment of diaphragmatic function at our institute after preliminary anatomical studies of injectate spread in fresh cadavers were promising. Additionally, as these intermuscular planes can be appreciated arthroscopically, the performance of this technique may even be feasible by the surgeons using conventional or liposomal formulations of local anaesthetics.10 Combined subscapularis plane and sub-omohyoid injections may serve as an alternative to peripheral nerve blocks for shoulder analgesia, with minimal impact on phrenic nerve function. Further well-designed randomized studies are required to evaluate this method in comparison to other analgesic modalities.
Correspondence | 833
100
Visual analog scale (mm)
90
#
80 70
*
60 50 40 30 20 10 Pulse
Colour Doppler Compression
Valsalva
Fig 1 Comparison of the four methods (pulse, colour Doppler, compression, and Valsalva methods) to differentiate between the common carotid artery and the internal jugular vein.
Declaration of interest None declared. artery (common carotid artery) and vein (internal jugular vein) differentiation in healthy volunteers using an ultrasound system with a 5–10 MHz transducer (iLookTM; SonoSite, Inc., Bothell, WA, USA). We introduced the following four differentiation methods: arterial pulse (pulse), colour Doppler, compression (vein reduction), and Valsalva (vein expansion) methods. At the end of training, participants rated the difficulty of the four methods on a visual analog scale, which ranged from 0 (extremely easy) to 100 mm (extremely difficult).2 Results obtained from each trial were compared using one-way repeated measures analysis of variance. A value of P < 0.05 was considered statistically significant.
References 1. Tokumine J, Lefor AT, Yonei A, Kagaya A, Iwasaki K, Fukuda Y. Three-step method for ultrasound-guided central vein catheterization. Br J Anaesth 2013; 110: 368–73 2. Komasawa N, Mihara R, Fujiwara S, Minami T. Significance of basic airway management simulation training for medical students. J Clin Anesth 2016; 32: 29
doi: 10.1093/bja/aew371
Unusual position of J-guide wire during ultrasound-guided subclavian vein catheterization T. Saranteas*, I. Koliantzaki Athens, Greece *E-mail: [email protected]
Editor—We conducted a retrospective analysis of all the ultrasound-guided catheterizations in which unusual J-guide wire atypical positions had been identified. The protocol included ultrasound, long-axis viewing of the J-guide wire,1 2 always before dilatation of the axillary/subclavian vein. The catheterization of the subclavian veins was performed according to the technique of Fragou and colleagues.1 All ultrasound-guided venous catheterizations were performed by a competent consultant anaesthetist with great experience in this technique. Manual ultrasound examinations were conducted using a high-frequency, linear transducer on a portable ultrasound unit (CX 50, Phillips Healthcare, The Netherlands; or Vivid I, GE Healthcare, Waukesha, WI, USA).
The central venous catheterizations took place on patients in the postoperative acute care unit, operating theatres, and the cardiothoracic care unit. Owing to the retrospective design of the study, formal research ethics committee approval and patients’ written informed consent for publication of this manuscript and accompanying images were deemed unnecessary. According to our results, throughout a 70 month period, 220 subclavian ultrasound-guided catheterizations were conducted, and all the potential complications were recorded in our archives. The J-guide wire was clearly seen in 220 out of 220 (100%) patients. In 13 out of 220 (5.9%) subclavian vein catheterizations, unusual J-wire positions in the lumen of the subclavian vein were acknowledged. Unusual positions of the J-wire included the
Downloaded from http://bja.oxfordjournals.org/ at Eccles Health Sci Lib-Serials on December 12, 2016
0
The subjective difficulty of each differentiation method is shown in Fig. 1. There was no significant difference in subjective difficulty between pulse and colour Doppler methods (P ¼ 0.99). The compression method was easier than colour Doppler and pulse methods (P < 0.001 each). The Valsalva method was less difficult compared with the other three (P < 0.001 vs pulse or colour Doppler). Differentiation between the internal jugular vein and the common carotid artery is the first and most important step in US-CVC. According to our survey, medical students found arterial pulse and colour Doppler methods more difficult than other ultrasound image-based methods. This might be associated with the fact that the vein often shows pulsatory motion with artery, and colour Doppler also captures venous flow. In contrast, vein collapse by the compression method and vein enlargement by the Valsalva method were considered relatively easy even for novices. A combination of the compression and Valsalva methods may be effective for novice doctors to differentiate between the internal jugular vein and the common carotid artery on ultrasound images.