Subcostal approach to anterior quadratus lumborum block for pain control following open urological procedures.

In the case of open urological surgeries, analgesic coverage at mid thoracic dermatomal levels is required. As shown in cadaveric studies, the site of QL block injection is an important determinant of the extent of dye spread and presumably local anesthetic dermatomal coverage. In this case series, we evaluated dermatomal blockade and analgesic efficacy of a subcostal approach to anterior QL block following open urological surgeries. Twenty-two adult patients undergoing renal transplant surgery (60%) and open nephrectomy (40%) received unilateral ultrasound-guided subcostal anterior QL block with catheter insertion. Sensory level, pain score (numeric rating scale, NRS), local anesthetic consumption, and opioid consumption (morphine equivalent dose, MED) were assessed daily for 3 days. The block achieved sensory blockade between T6-7 and L1-2. The most frequently affected dermatomes were T8 -T12 and the number of blocked segments was 3 (mean 2.8). The median (interquartile range Q1, Q3) of NRS pain score was 3.7 (2.8-5.5), 3.3 (2.4-4.7), 2.9 (1.9-3.6), and 2.3 (1.0-4.2) on POD0, POD1, POD2, and POD3, respectively. Our preliminary data showed that the subcostal approach to anterior QL block provides appropriate thoracic dermatome level needed for analgesia following open urological surgical procedures between T6-7 and L1-2.