Analgesic Effect of Ultrasound-Guided Bilateral Subcostal Anterior Quadratus Lumborum Block in Laparoscopic Colorectal Surgery: A Randomized Controlled Trial

Postoperative pain management is a critical factor in enhancing recovery and ambulation following laparoscopic colorectal surgery. Effective analgesia is necessary to reduce complications, improve patient comfort, and shorten hospital stays. In this context, multimodal analgesia is a commonly used strategy that combines various analgesic drugs, such as paracetamol, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids, to manage pain more effectively by targeting different pathways.

Although opioids are considered the gold standard for postoperative pain control, their use is associated with several undesirable side effects, including nausea, vomiting, dizziness, constipation, and respiratory depression. These opioid-related complications can delay recovery, increase patient discomfort, and extend hospital stays. Therefore, minimizing opioid consumption while still providing effective pain relief is a primary goal in postoperative pain management, particularly for surgeries such as laparoscopic colorectal procedures.

To achieve this goal, regional anesthesia techniques have gained increasing popularity. These techniques, such as interfascial plane blocks, have the potential to reduce opioid use and improve pain control by targeting specific nerve pathways. One of the more recent approaches is the quadratus lumborum block (QLB), which involves the injection of local anesthetics near the quadratus lumborum muscle. This block is particularly useful in abdominal surgeries because it can provide pain relief by affecting both somatic and sympathetic nerves, leading to broader and more effective pain coverage.

The QLB has four different approaches: anterior, lateral, posterior, and intramuscular. The anterior QLB is of particular interest in this setting because it involves the injection of local anesthetic between the quadratus lumborum and psoas muscles, potentially allowing the anesthetic to spread into the thoracic paravertebral space. This spread could result in the blockade of both the somatic nerves and the thoracic sympathetic chain, offering more comprehensive pain relief that is beneficial for abdominal surgeries like colorectal procedures.

The potential advantages of the anterior QLB in laparoscopic colorectal surgery include reduced postoperative pain, decreased opioid consumption, and fewer opioid-related side effects. Additionally, regional anesthesia techniques like QLB may reduce postoperative complications, including respiratory issues, which are particularly important in abdominal surgeries that involve the diaphragm and lower thoracic nerves.