PedsAnesthesiaNet

Abdominal wall blocks: Difference between revisions

Page Discussion

Abdominal wall blocks (view source)

Revision as of 18:49, 30 October 2021

1,891 bytes added ,  2 years ago
no edit summary
No edit summary
No edit summary
Line 27: Line 27:
* In infants the average nerve-peritoneum distance is only 3.3mm<ref>Willschke H, Marhofer P, Bosenberg A et al. Ultrasonography for ilioinguinal/iliohypogastric nerve blocks in children. Br J Anaesth. 2005; 95: 226-230.</ref> .
* In infants the average nerve-peritoneum distance is only 3.3mm<ref>Willschke H, Marhofer P, Bosenberg A et al. Ultrasonography for ilioinguinal/iliohypogastric nerve blocks in children. Br J Anaesth. 2005; 95: 226-230.</ref> .
* The fascial plane between the transversus abdominis muscle and the transversalis fascia is in continuity with the space around the femoral nerve.
* The fascial plane between the transversus abdominis muscle and the transversalis fascia is in continuity with the space around the femoral nerve.
[[File:Anatomy of the ilioinguinal-iliohypogastric nerve block.jpg|thumb|'''Figure 1'''. Anatomy of the ilioinguinal/iliohypogastric nerve block]]


=== Dose ===
=== Dose ===
Line 37: Line 38:


==== Landmark technique ====
==== Landmark technique ====
[[File:Injection point for the ILNB.jpg|left|thumb|'''Figure 2.''' The injection point for the ILNB should be equal to the child’s finger breadth medial to the ASIS, not the operator’s finger..]]
Place the patient supine. Clean the skin over the lower quadrant of the abdominal wall, including the skin over the anterior superior iliac spine (ASIS). Draw up the appropriate dose of local anaesthetic. The needle insertion point is close to the ASIS, approximately 2 - 5mm medial to the ASIS on a line drawn between the ASIS and the umbilicus.<ref>Weintraud M, Marhofer P, Bosenberg A et al. Ilioinguinal/ iliohypogastric blocks in children: where do we administer the local anesthetic without direct visualization? Anesth Analg. 2008; 106: 89-93.</ref> Some suggest using the child’s finger as an appropriate guide for the distance from the ASIS to the injection point (NOT the operator’s finger! - see Figure 2). It is important to keep the injection point high, away from the skin crease in the groin where the surgeon will make the incision; otherwise the operating field will be obscured.
Place the patient supine. Clean the skin over the lower quadrant of the abdominal wall, including the skin over the anterior superior iliac spine (ASIS). Draw up the appropriate dose of local anaesthetic. The needle insertion point is close to the ASIS, approximately 2 - 5mm medial to the ASIS on a line drawn between the ASIS and the umbilicus.<ref>Weintraud M, Marhofer P, Bosenberg A et al. Ilioinguinal/ iliohypogastric blocks in children: where do we administer the local anesthetic without direct visualization? Anesth Analg. 2008; 106: 89-93.</ref> Some suggest using the child’s finger as an appropriate guide for the distance from the ASIS to the injection point (NOT the operator’s finger! - see Figure 2). It is important to keep the injection point high, away from the skin crease in the groin where the surgeon will make the incision; otherwise the operating field will be obscured.


Line 42: Line 44:


==== Ultrasound guided technique ====
==== Ultrasound guided technique ====
[[File:Ultrasound probe position for iliinguinal-iliohypogastric.jpg|thumb|'''Figure 3.''' Ultrasound probe position for iliinguinal/iliohypogastric nerve block]]
Position the patient supine and clean the skin. Place a high frequency linear probe on the anterior abdominal wall along the line joining the anterior superior iliac spine (ASIS) and the umbilicus (a small footprint probe is useful for infants). (See Figure 3).
Position the patient supine and clean the skin. Place a high frequency linear probe on the anterior abdominal wall along the line joining the anterior superior iliac spine (ASIS) and the umbilicus (a small footprint probe is useful for infants). (See Figure 3).


The ASIS is the most easily recognizable landmark for this block, it appears as a dark echo-lucent shadow beneath a hyperechoic peak and should be kept at the lateral part of the screen for orientation. Identify (always from the inside out) the peritoneum (hyperechoic line, underneath it you may see peristalsis), transversus abdominis muscle, and internal oblique muscle. The external oblique muscle may not be visible as a distinct muscle layer at this level as it may have become an aponeurosis.




The ASIS is the most easily recognizable landmark for this block, it appears as a dark echo-lucent shadow beneath a hyperechoic peak and should be kept at the lateral part of the screen for orientation. Identify (always from the inside out) the peritoneum (hyperechoic line, underneath it you may see peristalsis), transversus abdominis muscle, and internal oblique muscle. The external oblique muscle may not be visible as a distinct muscle layer at this level as it may have become an aponeurosis. Slide the probe up over the iliac crest, whilst maintaining the same orientation of the probe, to bring all three muscles into view as three distinct layers. This may be useful if there is any doubt about the anatomy and the relevant planes. The ilioinguinal and iliohypogastric nerves are seen in close proximity to each another as two small round hypoechoic structures with a hyperechoic border. They lie in the plane between the internal oblique muscle and the transversus abdominis muscle close to the ASIS. In children the average distance from the ilioinguinal nerve to the ASIS is 7mm.<ref name=":0" />
Slide the probe up over the iliac crest, whilst maintaining the same orientation of the probe, to bring all three muscles into view as three distinct layers. This may be useful if there is any doubt about the anatomy and the relevant planes.  
[[File:Ultrasound landmarks for iliinguinal-iliohypogastric.jpg|thumb|'''Figure 4.''' Ultrasound landmarks for iliinguinal/iliohypogastric nerve block. ASIS=anterior superior iliac spine; EO=external oblique muscle; IO=internal oblique muscle; TA=transversus abdominus muscle; I=ilium. Arrow shows location of the nerves.]]




The ilioinguinal and iliohypogastric nerves are seen in close proximity to each another as two small round hypoechoic structures with a hyperechoic border. They lie in the plane between the internal oblique muscle and the transversus abdominis muscle close to the ASIS. In children the average distance from the ilioinguinal nerve to the ASIS is 7mm.<ref name=":0" />
Insert the block needle in plane from medial to lateral and ensure that the needle tip is visible at all times as it is advanced. Deposit local anaesthetic around the nerves in the transversus abdominis plane. Note that it may not always be easy to visualise the nerves, in this cause you could place the local anaesthetic in the transversus abdominis plane. If you have any concerns regarding the proximity of your injection to the nerve use a higher volume of local anaesthetic (e.g. 0.2ml.kg-1 0.25% bupivacaine).  
Insert the block needle in plane from medial to lateral and ensure that the needle tip is visible at all times as it is advanced. Deposit local anaesthetic around the nerves in the transversus abdominis plane. Note that it may not always be easy to visualise the nerves, in this cause you could place the local anaesthetic in the transversus abdominis plane. If you have any concerns regarding the proximity of your injection to the nerve use a higher volume of local anaesthetic (e.g. 0.2ml.kg-1 0.25% bupivacaine).  


Line 74: Line 82:


=== Techniques ===
=== Techniques ===
[[File:Injection point for rectus sheath block.jpg|thumb|'''Figure 5.''' Injection point for rectus sheath block for repair of umbilical hernia]]


==== Landmark technique ====
==== Landmark technique ====
Line 79: Line 88:


Introduce a short-bevelled needle perpendicularly through the skin Advance the needle medially at an angle of 60° towards the umbilicus. Identify the anterior sheath by moving the needle back and forth until a scratching sensation is felt; a pop is felt as the needle passes through the anterior sheath. Advance the needle through the muscle with continued movement of the needle until a scratching is again felt (this indicates the posterior sheath). If there is resistance to injection, it is not sited correctly. Repeat the technique for the opposite side. In children under 10 years of age the rectus muscle is rarely greater than 1cm in thick, therefore when performing this technique the needle should not be inserted any further than this. The depth of the posterior rectus sheath in children is unpredictable, and many advocate using ultrasound for this reason.<ref>Willschke H, Bosenberg A, Marhofer P et al. Ultrasonographyguided rectus sheath block in paediatric anaesthesia--a new approach to an old technique. Br J Anaesth. 2006; 97: 244-249.</ref>
Introduce a short-bevelled needle perpendicularly through the skin Advance the needle medially at an angle of 60° towards the umbilicus. Identify the anterior sheath by moving the needle back and forth until a scratching sensation is felt; a pop is felt as the needle passes through the anterior sheath. Advance the needle through the muscle with continued movement of the needle until a scratching is again felt (this indicates the posterior sheath). If there is resistance to injection, it is not sited correctly. Repeat the technique for the opposite side. In children under 10 years of age the rectus muscle is rarely greater than 1cm in thick, therefore when performing this technique the needle should not be inserted any further than this. The depth of the posterior rectus sheath in children is unpredictable, and many advocate using ultrasound for this reason.<ref>Willschke H, Bosenberg A, Marhofer P et al. Ultrasonographyguided rectus sheath block in paediatric anaesthesia--a new approach to an old technique. Br J Anaesth. 2006; 97: 244-249.</ref>
[[File:Ultrasound probe position for rectus sheath block.jpg|left|thumb|'''Figure 6.''' Ultrasound probe position for rectus sheath block]]


==== Ultrasound technique ====
==== Ultrasound technique ====
Position the patient supine. Select the screen depth (in neonates this will usually be 2cm, infants 3cm, thereafter 4cm). A high frequency linear probe is placed transverse on the abdomen, midline above the umbilicus (see Figure 6). The initial image will have the linea alba in the midline, with a rectus abdominis muscle either side. Posterior to the rectus muscle there are two hyperechoic lines (“train track”): the more superficial one is the posterior part of the rectus sheath and the deeper one is the peritoneum. Use the Doppler to identify the epigastric vessels, although this is not easy in small children (See Figure 7).
Position the patient supine. Select the screen depth (in neonates this will usually be 2cm, infants 3cm, thereafter 4cm). A high frequency linear probe is placed transverse on the abdomen, midline above the umbilicus (see Figure 6). The initial image will have the linea alba in the midline, with a rectus abdominis muscle either side. Posterior to the rectus muscle there are two hyperechoic lines (“train track”): the more superficial one is the posterior part of the rectus sheath and the deeper one is the peritoneum. Use the Doppler to identify the epigastric vessels, although this is not easy in small children (See Figure 7).
 
[[File:Ultrasound landmarks for rectus sheath block.jpg|thumb|'''Figure 7.''' Ultrasound landmarks for rectus sheath block: L=linea alba; R=rectus abdominis muscle; LA=local anaesthetic; AS=anterior rectus sheath; PS=posterior rectus sheath; A=epigastric artery (blood flow seen with colour Doppler function). Note needle visible over its whole length]]
Insert the block needle in-plane from lateral to medial. Note it can be difficult to puncture the skin with a block needle (either lift the skin and push the needle through or make a knick in the skin using a sharp bevelled needle). The needle is advanced from lateral to medial, in a shallow trajectory; aim to position the tip of the needle between the rectus muscle and the posterior rectus sheath. Stop the needle tip just superficial to the first white line (the posterior sheath); often a small ‘give’ is felt as you come out of the muscle into the potential posterior space. The needle is positioned correctly if the rectus sheath peels away from the muscle during injection of the local anaesthetic. Deposit local anaesthetic in this potential space between the rectus abdominis muscle and the posterior rectus sheath. In neonates you could use saline to identify the correct plane, avoiding the waste of the limited local anaesthetic. Note that in small children it is possible to use a large footprint probe in the midline and block both sides without adjusting the probe. Spread of the local anaesthetic after injection can be assessed by turning the probe into a paramedian longitudinal plane.
Insert the block needle in-plane from lateral to medial. Note it can be difficult to puncture the skin with a block needle (either lift the skin and push the needle through or make a knick in the skin using a sharp bevelled needle). The needle is advanced from lateral to medial, in a shallow trajectory; aim to position the tip of the needle between the rectus muscle and the posterior rectus sheath. Stop the needle tip just superficial to the first white line (the posterior sheath); often a small ‘give’ is felt as you come out of the muscle into the potential posterior space. The needle is positioned correctly if the rectus sheath peels away from the muscle during injection of the local anaesthetic. Deposit local anaesthetic in this potential space between the rectus abdominis muscle and the posterior rectus sheath. In neonates you could use saline to identify the correct plane, avoiding the waste of the limited local anaesthetic. Note that in small children it is possible to use a large footprint probe in the midline and block both sides without adjusting the probe. Spread of the local anaesthetic after injection can be assessed by turning the probe into a paramedian longitudinal plane.


== TRANSVERSUS ABDOMINIS PLANE BLOCK (TAP) BLOCK ==
== TRANSVERSUS ABDOMINIS PLANE BLOCK (TAP) BLOCK ==
The standard transversus abdominis plane (TAP) block provides intraoperative and postoperative analgesia for lower abdominal incisions. A subcostal TAP block can be provide analgesia for abdominal surgery above the umbilicus. TAP block can be performed unilaterally (e.g. inguinal hernia repair), or bilaterally (e.g. for laparoscopic surgery). It may be used as an alternative to an epidural, but it does not provide visceral analgesia; it should be performed after induction of anaesthesia, and adequate anaesthesia should be provided during visceral manipulation. A comprehensive review of the transversus abdominis plane (TAP) block can be found in WFSA ATOTW 239.<ref>Russon K et al. Transversus abdominus plane block. WFSA Anaesthesia Tutorial of the Week 2011 No. 239. <nowiki>http://www.wfsahq.org/components/com_virtual_</nowiki> library/media/ea51ff0934644a9e41bcf82f65a96a58- 474f4fcc0e20052dd9ed683ca9995db2-239-TransversusAbdominus-Plane-Block.pdf</ref>
The standard transversus abdominis plane (TAP) block provides intraoperative and postoperative analgesia for lower abdominal incisions. A subcostal TAP block can be provide analgesia for abdominal surgery above the umbilicus. TAP block can be performed unilaterally (e.g. inguinal hernia repair), or bilaterally (e.g. for laparoscopic surgery). It may be used as an alternative to an epidural, but it does not provide visceral analgesia; it should be performed after induction of anaesthesia, and adequate anaesthesia should be provided during visceral manipulation. A comprehensive review of the transversus abdominis plane (TAP) block can be found in WFSA ATOTW 239.<ref>Russon K et al. Transversus abdominus plane block. WFSA Anaesthesia Tutorial of the Week 2011 No. 239. <nowiki>http://www.wfsahq.org/components/com_virtual_</nowiki> library/media/ea51ff0934644a9e41bcf82f65a96a58- 474f4fcc0e20052dd9ed683ca9995db2-239-TransversusAbdominus-Plane-Block.pdf</ref>
[[File:Ultrasound probe position for the transversus abdominis plane.jpg|thumb|'''Figure 8.''' Ultrasound probe position for the transversus abdominis plane (TAP) block]]




Line 93: Line 104:


=== Anatomy ===
=== Anatomy ===
• The skin of the anterior abdominal wall is supplied by the ventral rami of the inferior six thoracic spinal nerves (T7 to T12).
• In the lateral part of the anterior abdominal wall there are 3 muscle layers, from deep to superficial they are: the transversus abdominis muscle (TA, it is the most internal of the 3 muscle layers), the internal oblique muscle (IO, it is positioned in-between TA and EO) and the external oblique muscle (EO, it is the largest and most superficial of the 3 muscles).


• The ventral rami of T 7 to T12 run in the plane between the transversus abdominis muscle and the internal oblique muscle: the transversus abdominis plane (TAP).  
* The skin of the anterior abdominal wall is supplied by the ventral rami of the inferior six thoracic spinal nerves (T7 to T12).
* In the lateral part of the anterior abdominal wall there are 3 muscle layers, from deep to superficial they are: the transversus abdominis muscle (TA, it is the most internal of the 3 muscle layers), the internal oblique muscle (IO, it is positioned in-between TA and EO) and the external oblique muscle (EO, it is the largest and most superficial of the 3 muscles).
* The ventral rami of T 7 to T12 run in the plane between the transversus abdominis muscle and the internal oblique muscle: the transversus abdominis plane (TAP).  


=== Dose ===
=== Dose ===
Line 109: Line 119:


Identify the peritoneum and then the abdominal muscles: transversus abdominis, internal oblique, and external oblique. In obese children fascial planes may be present within the adipose tissue, this can lead to misidentification of the muscle layers; therefore always identify the muscle layers from deep to superficial.
Identify the peritoneum and then the abdominal muscles: transversus abdominis, internal oblique, and external oblique. In obese children fascial planes may be present within the adipose tissue, this can lead to misidentification of the muscle layers; therefore always identify the muscle layers from deep to superficial.
 
[[File:Ultrasound landmarks for TAP block.jpg|thumb|'''Figure 9.''' Ultrasound landmarks for TAP block: EO=external oblique muscle; IO=internal oblique muscle; TA=transversus abdominus muscle; LA=local anaesthetic; needle seen slanting from anterior.]]
The target is the fascial plane between the transversus abdominis and the internal oblique muscles. Advance the needle in an antero-posterior direction (See Figure 8). Aim to puncture the fascia on the deep aspect of the internal oblique muscle layer (a slight give or pop is often felt) (See Figure 9).
The target is the fascial plane between the transversus abdominis and the internal oblique muscles. Advance the needle in an antero-posterior direction (See Figure 8). Aim to puncture the fascia on the deep aspect of the internal oblique muscle layer (a slight give or pop is often felt) (See Figure 9).


Retrieved from "https://pedsanesthesia.net/wiki/index.php/Special:MobileDiff/1933"