The Analgesic Effect of Quadratus Lumborum Block and Its Postoperative Implication on Kidney Function

Summary

Regional anesthesia is frequently used in major surgery in association with general anesthesia to ensure adequate postoperative patient analgesia and to decrease the intra- and postoperative use of systemic analgesic drugs. Epidural analgesia (EP) is considered the standard regional analgesic technique that is widely used in abdominal surgery. Nonetheless, it has some limitations such as in colorectal surgery where complications in the form of muscular weakness, hemodynamic instability, and postural hypotension result in delayed patient ambulation.

For these limitations, peripheral nerve blocks can be considered safer with less incidence of complications compared to the central neuraxial blocks especially with the use of ultrasound (US) as a guide in their techniques. Also, avoidance of the hemodynamic instability that may affect the postoperative kidney function can be considered an important issue in patients with risk for postoperative acute kidney injury (AKI).

One of the latest techniques in the field of regional anesthesia is the quadratus lumborum (QL) block, which is based on US-guided injection of a local anesthetic agent into the thoracolumbar fascia surrounding the QL muscle. Several different approaches were described depending on the injection sites, for example, lateral, posterior, and anterior approaches . According to the ASRA-ESRA Delphi consensus, there was no consensus on naming quadratus lumborum block types where posterior QL had the strongest consensus in abdominal wall analgesia with 71%.

After the QL block, there is evidence that the injectate spreads to the paravertebral space where it blocks the thoracolumbar nerves and the thoracic sympathetic trunk. Because it produces an extensive sensory block leading to adequate postoperative analgesia besides decreasing the systemic analgesic consumption, QL block is now considered an effective regional block that can be used in major abdominal surgery.

40% of the cases diagnosed as having AKI occurred as a postoperative complication. Cardiac surgery carries the highest risk for AKI (18.7%), whereas general surgery comes second (13.2%). The risk factors of developing AKI may be general or causes related to the type and the setting of the surgery.

Fluid depletion is one of the major factors that can occur perioperatively and leads to renal hypoperfusion, with subsequent renal arteriolar changes, attempting to maintain a normal glomerular filtration rate. The sympathetic effects of the neuroendocrine hormones may lead to renal vasoconstriction, aiming to redistribute the blood to the medulla; however, it may lead to renal ischemia.

The renal blood flow can be assessed by a rapid bed-side noninvasive technique, using the renal Doppler resistive index (RI), which is one of the most fundamental parameters assessing renal perfusion, because it reflects the degree of the vascular resistance inside the kidney vascular bed and can be used to assess the modifications and the changes that occur in the renal blood flow.

No previous studies so far discussed the effect of QL block on postoperative creatinine and blood ureal nitrogen (BUN) levels. While, regarding epidural analgesia, multiple articles are investigating the effect of epidural on postoperative kidney function using various indices, such as serum creatinine, BUN, sodium clearance, and urine output. As far as the authors know, this is the first study using the RI renal flow as a comparative parameter between the QL block and EP analgesia.

This study aimed to assess the analgesic efficacy of QL block compared with epidural anesthesia as a primary outcome using the 10-point visual analog scale (VAS), time to first morphine requirement, and 24-hour morphine consumption. Also, to study the effect of both on postoperative kidney function as a secondary outcome using serum creatinine and BUN and renal flow assessment using renal Doppler.

Conditions

• Anesthesia

Interventions

PROCEDURE

Quadratous lumborum block

Quadratus Lumborum (QL) block is a new technique for analgesia of the abdominal wall muscles. Its mechanism depends on the injection of the local anesthetic agent between the abdominal wall muscles into the thoracolumbar fascia surrounding the Quadratus Lumborum muscle by ultrasound (US) guided technique.

PROCEDURE

Epidural anesthesia

Epidural analgesia is a gold standard analgesic technique for the majority of abdominal surgeries, yet it has some limitations in some surgeries as colorectal surgeries due to delayed ambulation due to muscular weakness and postural hypotension.

Sponsors & Collaborators

• Ain Shams University

  lead OTHER

Principal Investigators

• Reham M Hashim · Faculty of medicine - Ain shams university

Eligibility

Min Age

35 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-06-15

Primary Completion

2020-08-15

Completion

2020-09-22

Countries

• Egypt

Study Locations