This video demonstrates how to perform an ultrasound-guided iPACK (infiltration between the popliteal artery and the knee capsule) block as an adjuvant technique for postoperative pain control in a pediatric patient presenting for anterior cruciate ligament repair.
The iPACK (infiltration between the popliteal artery and the knee capsule) block is a relatively new technique designed to provide motor-sparing analgesia for the posterior aspect of the knee. It is often used in conjunction with the adductor canal block to enhance overall analgesia for surgeries like total knee replacement and anterior cruciate ligament reconstruction. The use of ultrasound guidance further enhances the accuracy of local anesthetic administration and reduces associated risks. This video demonstrates the technique for performing an ultrasound-guided iPACK nerve block for a 14-year-old patient presenting for anterior cruciate ligament repair. The procedure was completed without complications, offering the patient significant pain relief.
The iPACK (infiltration between the popliteal artery and the knee capsule) block is a peripheral nerve block designed to provide motor-sparing analgesia for the posterior aspect of the knee and is often used in conjunction with the adductor canal block to enhance overall analgesia for surgeries like total knee replacement and anterior cruciate ligament reconstruction. The goal of the ultrasound-guided iPACK block is to inject the local anesthetic into the plane between the popliteal artery and the femur, where the articular sensory nerves of the popliteal plexus are located. This video demonstrates the technique for performing an ultrasound-guided iPACK nerve block for a 14-year-old patient presenting for anterior cruciate ligament (ACL) repair.
Equipment Needed: A linear or curvilinear probe, a 100 mm hyperechoic nerve block needle, ropivacaine 0.2% or bupivacaine 0.25%, a 10 mL syringe, a syringe with normal saline for hydrodissection, ChloraPrep sticks, and sterile gloves.
Procedure: After inducing anesthesia and securing the airway, position the patient in a supine position with the leg flexed at the knee. Place a roll of blanket under the leg to elevate and support it. Sterilize the popliteal area using chlorhexidine. Position the probe transversely at or just above the popliteal crease to visualize the femoral condyles and the popliteal artery in cross-section. At this level, the femoral condyles appear as discontinuous, curved hyperechoic lines, and the popliteal artery is seen as a pulsating anechoic structure in the center of the scan. Move the probe cephalad while keeping the popliteal artery in view until the discontinuous, interrupted hyperechoic line of the condyles transforms into a continuous, hyper-echoic silhouette of the femoral shaft just cranial to the condyles. The plane between the popliteal artery and the femur is the target tissue space for infiltration, as it is where the articular branches traverse. Insert the needle using an in-plane, lateral-to-medial approach, positioning it parallel to the femur in the middle of the tissue plane. Aim to keep the needle closer to the femoral shaft to minimize the risk of injuring the popliteal artery. Advance the needle until the tip is positioned 1-2 cm beyond the medial border of the popliteal artery. Inject the local anesthetic solution in 3 mL aliquots as the needle is withdrawn. Ropivacaine 0.2% or Bupivacaine 0.25% can be used for this block. Typically, 20 mL (ranging from 15 to 25 mL) of local solution is infiltrated into the tissue plane.
The iPACK block was successfully completed without any complications. The patient tolerated the procedure well.
The ultrasound-guided iPACK (infiltration between the popliteal artery and the knee capsule) block is a regional anesthesia technique used to provide motor-sparing analgesia for the posterior aspect of the knee. The iPACK block targets articular branches that arise from the main trunks of the tibial, common peroneal, and obturator nerves that course through the space between the popliteal artery and the femur to innervate the knee's posterior capsule. The block selectively anesthetizes the sensory branches of these nerves in this space without affecting the motor branches of the tibial and peroneal nerves, thus leading to reduced pain to the posterior knee without motor weakness in the leg and foot. The iPACK block is often used in conjunction with adductor canal block for control of posterior knee pain in procedures such as anterior cruciate ligament (ACL) repairs or total knee arthroplasty (TKA) to enhance overall analgesia. The combination of adductor canal block and iPACK block is particularly effective because the adductor canal block alone may not provide sufficient pain relief for the posterior knee, as it spares sensory function to the posterior aspect of the knee. This combination has been shown to effectively minimize postoperative pain for patients undergoing TKA while minimizing opioid requirements and promoting early ambulation. The iPACK block can also serve as a great alternative to sciatic nerve block for control of posterior knee pain, as the sciatic nerve block causes motor weakness of the lower extremity, which can mask any signs of intraoperative common peroneal nerve injury such as foot drop. As the iPACK block targets only the sensory branches of the tibial, common peroneal, and obturator nerves, it has been found to reduce the incidence of foot drop due to its motor-sparing effect. Rare complications that may arise with iPACK block include potential peroneal nerve block causing foot drop, risk of intravascular injection, or risk of injury to nearby popliteal vessels. The use of ultrasound guidance can help improve precision and accuracy of this block to reduce any potential risks or complications. Absolute contraindications for the Ipack block are similar to those for other peripheral nerve blocks and include patient refusal and active infection at the injection site. Relative contraindications include a history of coagulopathy or use of antithrombotic medications, allergies to local anesthetics, and pre-existing neural deficits in the area affected by the block.
There are no conflicts to disclose in this case.
There are no acknowledgements.
1. Avila A, Triana J, buldo-licciardi M, et al. Poster 329: Adductor Canal Block versus Adductor Canal Block Plus IPACK Block for Post-Operative Analgesia Following ACL Reconstruction with Bone-Patellar Tendon-Bone Autograft: A Single-Blind, Randomized Controlled Study. Orthop J Sports Med. 2023;11(7 suppl3):2325967123S00297. Published 2023 Jul 31. doi:10.1177/2325967123S00297. PMCID: PMC10392505.
2. Sinha S. How I Do It: Infiltration Between Popliteal Artery and Capsule of Knee (iPACK). ASRA Pain Medicine. May 30, 2020. Accessed August 22, 2024. https://www.asra.com/news-publications/asra-newsletter/newsletter-item/asra-news/2020/05/03/how-i-do-it-infiltration-between-popliteal-artery-and-capsule-of-knee-(ipack).
3. Rodziewicz TL, Patel S, Garmon EH. Lower Extremity Blocks. In: StatPearls. Treasure Island (FL): StatPearls Publishing; October 18, 2023.
4. iPACK Block. In: Hadzic A. eds. Hadzic's Peripheral Nerve Blocks and Anatomy for Ultrasound-Guided Regional Anesthesia, 3e. McGraw-Hill; 2021. Accessed August 24, 2024.
https://accessanesthesiology.mhmedical.com/content.aspx?bookid=3074§ionid=256635574.
This video demonstrates how to place the pelvic binder quickly and correctly, which may be life-saving in cases of pelvic ring fractures with associated potential massive bleeding. Proper pelvic binder placement technique requires attention to some details, including the 5Ps (pulses, penis, pockets, pain and pulses), horizontal force application in opposing vectors and ensuring the pelvic binder is locked.
This video demonstrates an epidural catheter placement on a 2-year-old, 12kg male patient presenting for left hip osteotomy. His past medical history was remarkable for congenital heart defects, bilateral congenital hip dislocations, and a sacral dimple which is sometimes associated with neurologic spinal canal abnormalities. In this case, no neurologic anatomical abnormalities were demonstrated on the neonatal spine ultrasound. The patient was placed in a left lateral decubitus position. Using anatomical landmarks like Tuffier’s line or the intercristal line corresponding to L4-L5 level, the target level for needle placement was identified and marked. The patient’s skin was sterilized and draped under sterile conditions. An 18-gauge, 5 cm length Tuohy needle was used to encounter the epidural space. A general guideline for the depth to the epidural space from the skin is approximately 1mm/kg of body weight¹. Subsequently, a 20-gauge catheter was placed through the needle to a depth of 4.5 cm at the level of the skin. Negative aspiration of blood or CSF was confirmed. A test dose was calculated at 0.5 mcg/kg epinephrine or 0.1ml/kg of lidocaine 1.5% with epinephrine 1:200,000. In this case, a 1.2 mL test dose of lidocaine 1.5% with epinephrine 1:200,000 was given without any observed cardiovascular changes (e.g. ≥ 25% increase or decrease in T wave amplitude, HR increase ≥ 10 bpm, or SBP increase ≥ 15 mmHg)¹. Finally, the catheter was secured to the back of the patient. Parental consent was obtained for the publication of this video.
This video explains how electromyography endotracheal tubes work during thyroid surgery. Also known as, EMG ET tubes, these are a type of Intraoperative Neuromonitoring (IONM) which serve a big role preventing nerve injury by monitoring recurrent laryngeal nerve activity. Placement of the tube during intubation is important as the surface electrodes should be in contact with the vocal cords. Incorrect placement would render the tube ineffective and could cause damage to the nerve. Both, macintosh and video laryngoscopes can be used if there is poor visibility during intubation.
During surgery the tube may shift from its correct position for several reasons, primarily movement of the neck, so it’s important to check its correct placement throughout the duration of surgery. The tube itself has electrodes located at the tip. These electrodes come into contact with the vocal cords and detect electrical signals produced by the nerves. These signals are transmitted to a monitoring system which allows for continuous monitoring throughout the surgery. Once the EMG ET tube is properly placed, it can detect electrical signals produced by the nerve by using a stimulation probe. Whenever the nerve is stimulated surgeons and anesthesiologists can view the signals on a screen and listen to the sounds produced by pressing directly above the vocal cords.
The EMG signals are transmitted to a real-time monitoring system which helps surgeons view the signals on a screen and evaluate nerve integrity. During surgery this feedback helps surgeons adjust their technique to avoid nerve damage. Stimulation of the nerve creates a sinusoidal wave on the nerve integrity monitor along with an audible signal confirming its intactness. These waveforms, also known as electromyograms. In a normal resting state, should show very little electrical activity. The intensity can be seen by the amplitude of the wave. And the duration can provide information about the speed of muscle activation. A decrease or loss of EMG signals in response to nerve stimulation can indicate nerve damage or irritation.
Review Pediatric Ultrasound-Guided iPACK Block.