Single injection ultrasound‐guided rectus sheath blocks for children: Distribution of injected anesthetic

• Published in: Pediatric anesthesia 2019-03, Vol.29 (3), p.280-285
• Main Authors: Visoiu, Mihaela, Hauber, John, Scholz, Stefan, Bosenberg, Adrian
• Format: Article
• Language: English
• Subjects: anesthesia; anesthetic; Data collection; hernia; intercostal; laparoscopic; local; nerves; pediatric; pubic; rectus; regional; repair; sheath; symphysis; Ultrasonic imaging; umbilicus
• ISSN: 1155-5645; 1460-9592
• DOI: 10.1111/pan.13577

Summary Background Single injection ultrasound‐guided rectus sheath blocks are used for postoperative analgesia after midline abdominal incisions, but the ultrasonographic spread of medication posterior to the rectus muscle has not been investigated. Aims The primary goal of this study was to determine the ultrasound‐measured medication spread superiorly and inferiorly after single injection ultrasound‐guided rectus sheath blocks and to calculate the incidence of cases with spread up to the subcostal margin and below of umbilicus. The secondary goals were to correlate the spread with the volume of medication administered and with the patient's age, weight, height, sex, and body mass index. Methods Pediatric patients who underwent single injection ultrasound‐guided rectus sheath blocks and underwent data collection of ultrasonographic information on medication spread along the plane of the posterior rectus sheath were identified retrospectively from an acute pain service database at UPMC Children's Hospital of Pittsburgh. Results Sixty‐eight children, 10.2 ± 4.2 (mean ± SD) years old, 41.7 ± 17.9 kg, 140 ± 24.6 cm, had complete data collection. Mean injected volume of ropivacaine was 8.3 ± 2.8 mL (right) and 8.2 ± 2.8 mL (left). The average spread was measured as 3.9 ± 1.4 cm (right) and 3.4 ± 1.3 cm (left) cranial to the umbilicus, and 1.5 ± 1.6 cm (right) and 1.6 ± 1.4 cm (left) caudal to the umbilicus. Complete spread up to the level of the subcostal margin was observed in 52.9% (n = 36; right) and 36.8% (n = 25; left) of cases. The spread correlated closely with the volume of injected ropivacaine (right: 0.556, P