Ultrasound guidance versus electrical stimulation for femoral perineural catheter insertion.
OBJECTIVE
Continuous femoral nerve blocks provide potent analgesia and other benefits after knee surgery. Perineural catheter placement techniques using ultrasound guidance and electrical stimulation (ES) have been described, but the optimal method remains undetermined. We tested the hypothesis that ultrasound guidance alone requires less time for femoral perineural catheter insertion and produces equivalent results compared with ES alone.


METHODS
Preoperatively, patients receiving a femoral perineural catheter for knee surgery were randomly assigned to either ultrasound guidance with a nonstimulating catheter or ES with a stimulating catheter. The primary outcome was the catheter placement procedure time (minutes) starting when the ultrasound transducer (ultrasound group) or catheter insertion needle (ES group) first touched the patient and ending when the catheter insertion needle was removed after catheter insertion.


RESULTS
Perineural catheters placed with ultrasound guidance (n = 20) took a median (10th-90th percentiles) of 5.0 (3.9-10.0) minutes compared with 8.5 (4.8-30.0) minutes for ES (n = 20; P = .012). All ultrasound-guided catheters were placed according to the protocol (n = 20) versus 85% of ES-guided catheters (n = 20; P = .086). Patients in the ultrasound group had a median procedure-related discomfort score of 0.5 (0.0-3.1) compared with 2.5 (0.0-7.6) for the ES group (P = .015). There were no vascular punctures with ultrasound guidance versus 4 in the ES group (P = .039).


CONCLUSIONS
Placement of femoral perineural catheters takes less time with ultrasound guidance compared with ES. In addition, ultrasound guidance produces less procedure-related pain and prevents inadvertent vascular puncture.
Department of Anesthesiology, University of California, San Diego Medical Center, 200 W Arbor Dr, San Diego, CA 92103-8770, USA. ermariano@ucsd.edu
Edward R
ER
Mariano
Vanessa J
VJ
Loland
NavParkash S
NS
Sandhu
Richard H
RH
Bellars
Michael L
ML
Bishop
Robert
R
Afra
Scott T
ST
Ball
R Scott
RS
Meyer
Rosalita C
RC
Maldonado
Brian M
BM
Ilfeld
D000328:Adult; D000368:Aged; D002406:Catheterization, Peripheral / Q000379:methods*; D004558:Electric Stimulation / Q000379:methods*; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D013997:Time Factors; D018084:Ultrasonography, Interventional / Q000379:methods*