Vol.:(0123456789) 1 3 Journal of Anesthesia https://doi.org/10.1007/s00540-018-2563-z ORIGINAL ARTICLE Ultrasound-guided quadratus lumborum block in pediatrics: trans- muscular versus intra-muscular approach Mostafa M. Hussein 1 Received: 13 July 2018 / Accepted: 3 October 2018 © Japanese Society of Anesthesiologists 2018 Abstract Purpose Quadratus lumborum (QL) block has four approaches. However, there is difference between the four approaches regarding efficacy, safety and adverse effects. The primary objective of this study is to compare the analgesic effect between trans-muscular and intra-muscular approaches of the QL block in pediatric patients for elective lower abdominal surgery. Methods 54 patients aged between 1 and 6 years were enrolled. Patients of both genders were selected. The patients were randomly classified into two groups: Group TQL includes patients (27 patients) in whom bilateral QL block was performed using trans-muscular approach, and Group IQL (27 patients), which underwent bilateral QL block using an intra-muscular approach. The primary outcome measure was the number of patients who require rescue analgesia in the first 24 h. The sec- ondary outcome measures were FLACC score, heart rate, non-invasive blood pressure at 2, 4, 6, 12, and 24 h postoperatively, and postoperative complications (e.g., quadriceps muscle weakness, local hematoma). Results In the first 24 h after surgery, 13 patients in the IQL group (48.1%) required rescue analgesia, whereas only five patients in the TQL group (18.5%) required rescue analgesia. The FLACC score was lower in the TQL group than the IQL group at all time intervals up to 24 h postoperatively. In the TQL group, eight patients (29.6%) developed quadriceps weak- ness; whereas, only one patient (3.7%) in the IQL group developed quadriceps weakness. Conclusion TQL is better than IQL in the analgesic efficacy following the pediatric lower laparotomy. Keywords Ultrasound · Quadratus lumborum · Pediatrics · Trans-muscular · Intra-muscular Introduction Ultrasound-guided quadratus lumborum (QL) block is con- sidered now as one of the novel truncal abdominal blocks, as it is effective in preventing somatic pain associated with upper and lower abdominal surgeries [1]. The first description of the QL block was made by Blanco in 2007 [2], where the local anesthetic was deposited at the anterolateral aspect of the QL muscle. Later, further modi- fications were performed to the QL block. Trans-muscular QL block was demonstrated by Dam et al. [3], where the local anesthetic is injected anterior between the QL muscle and the Psoas Major (PM) muscle. Trans-muscular QL block can be performed by oblique paramedian approach in the lateral position as well, 3 cm lateral to the spinous process of L2. Moreover, it can be called the subcostal QL block. This approach allows the PM muscle to provide a barrier protection against peritoneal cavity invasion [4]. Lastly, the intra-muscular QL block was tried where the local anesthetic is injected directly into the QL muscle [5]. Scarce information is available about one approach of the QL block predominating over the other. Although compari- son of different approaches of the QL block are previously investigated in adult population [6, 7], I think this is the first prospective, single blinded, randomized study comparing the postoperative analgesic effect between trans-muscular and intra-muscular approaches of the QL block in pediatric age groups. The primary aim of this study is to investigate the differ- ence in analgesic efficacy between the trans-muscular and intra-muscular approaches of the QL block under ultrasound guidance in pediatrics. The secondary aims are the recording of hemodynamic parameters and the incidence of postopera- tive complications especially quadriceps muscle weakness and local hematoma between the two approaches. Based on * Mostafa M. Hussein mostafa.mansor@med.asu.edu.eg 1 Department of Anesthesiology, Ain Shams University, 5 Abdel-Azim Salama Street, Nasr city, Cairo 11727, Egypt