Trained and skilled medical providers, including anesthesiologists, can perform TAP blocks. Typically a second healthcare provider or nurse is required for time-out before starting the procedure, and to assist with the injection of local anesthetic.

The clinician must discuss the risks, benefits, and alternatives with the patient and obtain informed consent. The patient should be monitored using continuous EKG, continuous pulse oximetry, and blood pressure cuff cycling every 5 minutes. The patient should have IV access before the procedure. Position the patient supine and uncover the abdomen. Be sure to thoroughly clean the skin over the anterolateral abdomen, from the costal margin to iliac crest, followed by placement of sterile towels surrounding the border of the procedural field. A procedural time-out should take place prior to starting the procedure.

Landmark-based TAP blocks are an uncommon choice, as an ultrasound machine is commonly available and has made regional anesthesia blocks safer and more reliable. Rafi first described the landmark-based technique. Using surface landmarks, the practitioner must identify the lumbar triangle of Petit, which is bound medially by the external oblique, inferiorly by the iliac crest, and posteriorly by the latissimus dorsi.[5] Once the triangle identified, and upon introducing the needle through the skin, a "double-pop" sensation, described by McDonnell, can be felt by the practitioner as the needle traverses through the fascia deep to the external oblique muscle (first pop), followed by penetration through the fascia deep to the internal oblique muscle (second pop).[2] At this point, the practitioner, after confirming negative aspiration for blood, will inject local anesthetic incrementally, aspirating every few milliliters to reduce the risk of intravascular injection. It is common for patients to have dull, pressure-like sensation during injection. 

Using a high-frequency linear or curvilinear ultrasound transducer orientated transversely, begin scanning the abdomen between the iliac crest and the costal margin at the mid-axillary line.[4] Note that the most superficial layer on ultrasound is skin and subcutaneous fat. The most superficial of the three muscular layers is the external oblique, followed by the internal oblique, and lastly, the transversus abdominis muscle. The internal oblique is classically the thickest layer in most patients, while the transversus abdominis muscle is often the thinnest layer. If uncertain, increase the depth of the ultrasound to confirm bowel beneath the transversus abdominis muscle, and be sure to avoid placing the needle in this region. Posteriorly scanning the internal oblique and transversus abdominis muscles shows the two layers come together to form the thoracolumbar fascia. Scanning medially, the aponeurosis of the three muscle layers can be seen coming together to form the rectus sheath. Upon identifying the transversus abdominis plane numb the patient's skin using lidocaine, then penetrate the skin with the block needle using an in-plane technique, making sure to visualize the needle tip on ultrasound throughout its entire trajectory. Upon entering the transversus abdominis plane (TAP) between the internal oblique and the transversus abdominis muscles, the local anesthetic is slowly and incrementally injected, after aspiration is negative for blood.

The TAP will begin to "unzip" as the local anesthetic is injected, pushing the transversus abdominis muscle deeper. Depending on the patient’s weight and the concentration of the local anesthetic, an injection of 15 to 20 ml of local anesthetic is typical. This technique describes a posterior TAP block, which is the most commonly performed. If a higher dermatomal coverage is required (T6-T9), the same technique can be used in the subcostal region, just medial to the anterior axillary line where these nerves enter into the abdominal wall. Local anesthetic spread along the TAP is thought to be responsible for the efficacy of the block, as shown by radiological studies.[6][7] Experience has shown that the efficacy of the block is improved when injecting 15 ml or more.[8] TAP blocks can be done bilaterally or unilaterally, depending on the location of the surgery. A surgeon may also perform an abdominal wall block from inside the abdominal cavity during surgery.[9]

Complications related to TAP blocks are rare. Given that abdominal wall blocks are field blocks, relying primarily on the volume of the local anesthetic to facilitate adequate blockade rather than targeting a specific nerve, neurological injury is rare. Neurologic injury may arise due to direct nerve trauma from the needle, hematoma, or local infection. Excessive needle insertion may also lead to complications such as intraperitoneal injection, visceral trauma, vascular injury, and liver trauma. Reports have also described transient femoral nerve palsy.[10] Ultrasound guidance helps to minimize these complications and is considered superior to landmark-based techniques that rely on subjective tactile pops through fascial planes. It is essential to recognize that local anesthetic injection within TAP occurs in an area that is well vascularized. Therefore, one should be cautious to avoid vascular puncture and intravascular injection. Local anesthetic systemic toxicity is a rare but known complication.

TAP blocks have become an important addition to multimodal pain management for abdominal wall surgery. The safety, ease, and effectiveness of the block make it an excellent adjunct to perioperative pain management. 

A team-based, interprofessional methodology should be implemented to ensure patient safety. Communication with the surgeon should take place to help assess the suitability of the block along with specific detail regarding the location of the incision, timing of the block, and other unique considerations. An appropriate time-out to promote patient safety is necessary before the start of the procedure. Maintaining meaningful verbal contact with the patient throughout the procedure is vital to monitor for any complications such as local anesthetic systemic toxicity, potential nerve injury, or visceral perforation. Practitioners should take extreme caution when handling sharps as accidental needle sticks may occur. Sharps require disposal using appropriately marked bins. Documentation of the procedure should include informed consent, date, time, procedure location, block technique, the medication used, volume and concentration of injectate, equipment used, ultrasound images, and documentation of any complications.

The interprofessional team will include clinicians (both general and specialists), nurses, surgical assistants, and pharmacists. The clinician should send the patient to the specialist, who will prepare the patient for the procedure in conjunction with the nursing staff.  The pharmacy will prepare the anesthetic and can act as a resource for any medication-related questions by the team. Nursing will assist during the procedure, and additional nursing duties are outlined below.  This type of interprofessional team paradigm will optimize the results from a TAP block leading to better patient outcomes. [Level V]

The nurse is in charge of setting up the instrument tray for the block. Also, the nurse may position and prep the patient for the procedure. The nurse is also responsible for making sure that the patient has signed consent and that the procedure is taking place on the correct side of the abdominal pathology.

Before starting the procedure, the nurse must make sure that resuscitative equipment is in the room. Also, one nurse should be dedicated to the monitoring of the patient during and after the procedure. In the recovery room, the nurse should assess the patient's hemodynamic status and evaluated the site of the block for bleeding.