G-PACK block for post-operative analgesia in a patient with morbid obesity : Saudi Journal of Anaesthesia

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G-PACK block for post-operative analgesia in a patient with morbid obesity

Das, Samaresh; Chatterjee, Nilay; Munjal, Manish1; Sharma, Gaurav2,

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Saudi Journal of Anaesthesia 17(2):p 287-288, Apr–Jun 2023. | DOI: 10.4103/sja.sja_381_22
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Dear Editor,

Knee surgeries are among the most common painful orthopedic procedures; inadequate pain control delays mobilization and faster functional recovery, which are essential to prevent complications such as venous thromboembolism.[1] Various studies were conducted and published regarding the nerve block in knee operations. However, control of post-operative pain was the primary concern.[2] At times, post-operative pain control is very challenging for both orthopedic surgeons and anesthetists. We successfully managed post-operative analgesia in a patella surgery with combined genicular nerve block and the inter-space between the popliteal artery and capsule of the knee (IPACK) block: we named it “G-PACK” block.

A 65-year-old, morbidly obese (weight 122 KG, BMI 56) woman was admitted with severe left knee pain and swelling after a fall, and an X-ray showed a compound fracture of the left patella [Figure 1]. She had obstructive sleep apnea, chronic obstructive pulmonary disease, and a history of deep vein thrombosis. She was allergic to morphine, oxycodone, and ibuprofen. A decision was made for open reduction and internal fixation of her left patella. Because of her comorbid conditions, it was crucial to mobilize her at the earliest. Surgery was performed under spinal anesthesia. After the spinal, the G-PACK block was performed under aseptic precautions and ultrasound guidance. We blocked supero-medial [Figure 2], supero-lateral, and infero-medial genicular nerves with levobupivacaine 0.25% (5 ml for each) for another 15 ml posteriorly for the IPACK [Figure 3]. She could move, could extend her right knee, and stood with support within 4 hours after the surgery. We measured her numerical pain rating (NRS) score at rest and during mobilization at 6, 12, and 24 hours post-operatively, which was 0/1, 3/4, and 3/5, respectively. Rescue analgesia was maintained with intravenous paracetamol and PRN intravenous fentanyl 25 micrograms before mobilization. Post-operatively after 24 hours, her NRS at rest and during physiotherapy was 4 and 6, respectively. She was discharged with oral paracetamol and codeine on the next day.

Figure 1:
X ray compound fracture of left patella
Figure 2:
Needle pathway and local anaesthesia injection in superomedial genicular nerve block
Figure 3:
Ultrasound image of IPACK block

Traditionally, anesthesia and analgesia for knee surgery are optimized by various methods, including general anesthesia; spinal, epidural, and regional nerve blocks; peri-articular infiltration; and systemic analgesia.[3] Recent evidence of ultrasound-guided lower extremity nerve blocks revealed satisfactory results as the sole anesthetic technique or post-operative analgesia.[4] The most commonly performed technique for post-operative analgesia for knee surgery is adductor canal block (ACB). However, in this patient, it was difficult to visualize because of the habitus. Moreover, there was evidence of motor block in ACB in recent studies.[5] For the past few years, different motor sparing nerve blocks have evolved for better patient care to facilitate early ambulation and discharge and prevent complications (e.g., fall, thromboembolism). The genicular nerve block is one such technique used traditionally for chronic knee pain for patients. Another recent addition for the management of post-operative knee surgery is the IPACK block.[6] We have combined both techniques for this particular patient (with a high body mass index and comorbidities). We introduced a new name – the G-PACK block. The surgeon did not infiltrate any local anesthesia agents in the field, and the post-operative analgesic requirement was significantly lower. Ours is the first report of combining two attractive regional techniques in knee surgery to the best of our knowledge. G-PACK can significantly help in early ambulation and hospital discharge.


The authors declare that they have explained and obtained consent from the patient for publication.

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Conflicts of interest

There are no conflicts of interest.


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