What are the indications of transversus abdominis plane block? With the help of a diagram describe the block?

 The transversus abdominis plane block is the technique of deposition of LA agent in the fascial plane between transversus abdominis muscle and internal oblique which is done either with ultrasound guided technology or anatomical landmark guided .

Indication

unilateral block: 

• Cholecystectomy
• Appendicectomy
• Nephrectomy
• Renal transplant

bilateral block

• Ventral hernia repair
• Lower section caesarian section
• Hysterectomy
• Inguinal hernia repair
• Bariatric surgery
• Colostomy closure

Technique of the block

Equipment:

1) Ultrasound machine with linear transducer ,

curvilinear may be needful in obese pt

2) Sterile cover and gel

3) Skin disinfectant like chlorhexidine 2%

4) Block needle with tubing (50 to 100mm and    

    20 to 21 G)

5) LA agent bupivacaine,ropovacaine

6) 2 20ml syringes containing the LA

Preparation

Informed consent is obtained

Iv cannula is placed

Position

The patient generally lies supine

Monitoring

the basic monitoring of HR,SPO2,BP

High frequency linear probe with gel in sterile transparent cover is placed on the anatomical site corresponding to subcostal ,lateral or posterior TAP block

The probe is moved up and down or rotated to bring the right image

The first layer is Skin and subcutaneous tissue 

The next three are muscle layers External Oblique, internal oblique and traversus abdomens,int oblique being the thickest

As the needle tip enters the block compartment,hydrodissction done

with normal saline and when the plane within the internal oblique and transversus abdominis is separated the LA agent of around 15 to 20ml is injected slowly after negative aspiration for blood

Complications

bowel injury, hematoma, intravascular injection of LA, intraperitonal injection.