Lumbar plexus in children. A sonographic study and its relevance to pediatric regional anesthesia.
BACKGROUND
Pediatric regional anesthesia has gained increasing interest over the past decades. The current study was conducted to investigate the lumbar paravertebral region and the lumbar plexus at L3-L4 and L4-L5 by means of sonography to obtain fundamentals for the performance of ultrasound-guided posterior lumbar plexus blocks.


METHODS
Thirty-two children (12 boys, 20 girls) with American Society of Anesthesiologists physical status I or II were enrolled in the current study. The lumbar paravertebral region was visualized at L3-L4 and L4-L5 on two corresponding posterior sonograms (longitudinal, transverse). The lumbar plexus had to be delineated, and skin-plexus distances were measured. In a series of five pediatric patients undergoing inguinal herniotomy, ultrasound-guided posterior lumbar plexus blocks at L4-L5 were performed.


RESULTS
The children were stratified into three age groups (group 1: > 3 yr and </= 5 yr; group 2: > 5 yr and </= 8 yr; group 3: > 8 yr and </= 12 yr). The lumbar plexus could be delineated at L3-L4 and L4-L5 in 19 of 20 cases in group 1, in 17 of 20 cases in group 2, in 22 of 24 cases at L3-L4 in group 3, and in 16 of 24 cases at L4-L5 in group 3. In all patients, the lumbar plexus was situated within the posterior part of the psoas major muscle. Skin-plexus distances showed statistical significant differences between groups 1 and 3 and between groups 2 and 3. The strongest positive correlation existed between skin-plexus distances and the children's weight. Ultrasound guidance enabled safe und successful posterior approaches to the lumbar plexus, thus resulting in effective anesthesia and analgesia of the inguinal region.


CONCLUSIONS
Sonography of the lumbar plexus in children proved to be feasible. Skin-plexus distances correlated with the children's weight rather than with their age. The sonographic findings were fundamental for the performance of successful ultrasound-guided posterior approaches in a small group of pediatric patients.
Section of Pediatric Radiology, Department of General Pediatrics, University of Innsbruck, Innsbruck, Austria. l.kirchmair@chello.at
Lukas
L
Kirchmair
Birgit
B
Enna
Gottfried
G
Mitterschiffthaler
Bernhard
B
Moriggl
Manfred
M
Greher
Peter
P
Marhofer
Stephan
S
Kapral
Ingmar
I
Gassner
D000375:Aging / Q000502:physiology; D000775:Anesthesia, Spinal; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006552:Hernia, Inguinal / Q000601:surgery; D006801:Humans; D008160:Lumbosacral Plexus / Q000000981:diagnostic imaging*; D008297:Male; D009339:Needles; D012867:Skin / Q000000981:diagnostic imaging; D014463:Ultrasonography