Transverse abdominis plane block (TAP) Dr. S. Parthasarathy MD, DA, DNB, Dip Diab.MD,DCA, Dip software based statistics, PhD (physiology) FICA

Definition Transversus abdominis plane (TAP) blocks involve injecting local anesthetic into the neurovascular plane between the internal oblique and transversus abdominis muscles. The neurovascular plane between the internal oblique and transversus abdominis muscles is known as the TAP plane, hence the term TAP block.

History Rafi first described the TAP block in 2001 A 24-gauge, blunt-tipped, 2- inch needle was then advanced perpendicular to the skin until a single confirmatory “pop” was appreciated. RAFI – xiphoid to pubis 2007 – Mcdonnel published TAP

Anatomy

The External Oblique Muscle Largest, most superficial Origin - Lower 8 ribs – runs down – iliac crest, inguinal ligament and linea alba

What is internal oblique

Origin – iliac crest, inguinal ligament Its’ fibres cover the anterolateral part of the abdomen inserting anteriorly into the linea alba, above the transversus abdominis muscle, and superiorly into the cartilages of the lower 6 ribs.

Internal oblique

The transversus abdominis muscle most internal of the 3 muscle layers, Its’ fibres arise from the inguinal ligament, the iliac crest, the lumbodorsal fascia and the inner surfaces of the cartilages from the lower 6 ribs. Its’ fibres run transversely across the abdomen ending in a broad aponeurosis. This aponeurosis is formed more laterally than the aponeuroses of the external and internal oblique muscles. It continues medially and inserts into the linea alba.

So four muscles

T7 to L1 nerves from the spinal cord traverse this plane TAP to supply the anterior abdominal wall Basis of block Includes ILIH T6 – T9 more anterior entry

These nerves travel within the TAP and undergo multiple divisions before providing sensory innervation to the skin, muscles, and parietal peritoneum of the anterolateral abdominal wall No to visceral pain

Indications Hernia repair Open appendicectomy Caesarian section Total abdominal hysterectomy Radical prostatectomy Midline laparotomy, cholecystectomy, umbilical hernia repair also !!

Rare – surgical, pain TAP blocks have provided surgical anesthesia in high-risk patients for abdominal wall hernia repair, emergency laparotomy, elective Cesarean delivery. Continuous TAP blockade has been used for treatment of chronic pain, for complex traumatic pelvic fractures and for rescue analgesia

Absolute contraindications Patient refusal, soft tissue infection of the abdominal wall and skin, abnormality at the needle insertion site. Coagulation status is an area of uncertainty with the TAP block and will require further investigation.

General precautions Asepsis Needles – blunted Local anesthetics – ligno + adrenaline, bupi ropi etc. ( usually 20 ml – 0.25 % bupi each side ) Diluents Gloves USG – steridrapes

Technique Subcostal Mid axillary Ilioinguinal Posterior PETIT Landmark guided Palpate iliac crest ant to post – dip felt – go posterior and above Go cranially – double pop Go close to the bone – single pop

Mid axillary – classical

Anatomy

Go posterior – TA will wane off EO IO Needle TA TAP

Plane exact

Subcostal approach

Subcostal T6 to T9 Aponeurosis and plane Drug Go posterior to deposit more Bilateral can be used

Subcostal TAP

Subcostal

Ilioinguinal TAP

Which type of block ?? Indications – depend upon area of nociception

Rectus sheath block The rectus sheath nerves are the terminal branches of the myocutaneous nerves (T8–L1) supplying the lower two- thirds of the anterior abdominal wall, including the muscle layers and the parietal peritoneum. They enter the rectus sheath through its lateral border (linea semilunaris) and pass towards the linea alba. Within the rectus sheath the nerves lie between the rectus abdominis muscle and the posterior wall of the sheath, and supply the central abdominal wall.

Rectus sheath block

Clinical usage Reduced VAS Reduced opioid requirements Reduced side effects epidura;l – VAS less but side effects

Complications Rectus Sheath BlockTAP BlockILH Block Injury to bowel & Peritoneum Deep inferior gastric vascular injection LA toxicity SC-TAP Hepatic injury Mid Axillary Injury to peritoneum and bowel Posterior Approach Injury to kidney LA toxicity Injury to bowel and Peritoneum

Quadratus lumborum block

Transversalis fascia plane block Local anesthetic injected between the transversus abdominis muscle and its deep investing transversalis fascia will spread over the inner surface of the quadratus lumborum muscle and block the proximal portions of the T12 and L1 nerves Iliac crest bone graft and hernia

Transversalis fascia plane block

Summary Definition Where Indications Contraindications Landmark USG types Complications Transversalis plane

Thank you all