TY - JOUR
T1 - Effects of Using the Posterior or Anterior Approaches to the Lumbar Plexus on the Minimum Effective Anesthetic Concentration (MEAC) of Mepivacaine Required to Block the Femoral Nerve
T2 - A Prospective, Randomized, Up-and-Down Study
AU - Cappelleri, Gianluca
AU - Aldegheri, Giorgio
AU - Ruggieri, Francesco
AU - Carnelli, Franco
AU - Fanelli, Andrea
AU - Casati, Andrea
PY - 2008/1
Y1 - 2008/1
N2 - Background and Objectives: To evaluate if psoas compartment block requires a larger concentration of mepivacaine to block the femoral nerve than does an anterior 3-in-1 femoral nerve block. Methods: Forty eight patients undergoing anterior cruciate ligament repair were randomly allocated to receive an anterior 3-in-1 femoral block (femoral group, n = 24) or a posterior psoas compartment block (psoas group, n = 24) with 30 mL of mepivacaine. The concentration of the injected solution was varied for consecutive patients using an up-and-down staircase method (initial concentration: 1%; up-and-down steps: 0.1%). Results: The minimum effective anesthetic concentration of mepivacaine blocking the femoral nerve in 50% of cases (ED50) was 1.06% ± 0.31% (95% confidence interval [CI], 0.45%-1.68%) in the femoral group and 1.03% ± 0.21% (95% CI, 0.6%-1.45%) in the psoas group (P = .83). The lateral femoral cutaneous and obturator nerves were blocked in 4 (16%) and 5 (20%) femoral group patients as compared with 20 (83%) and 19 (80%) psoas group patients (P = .005 and P = .0005, respectively). Intraoperative analgesic supplementation was required by 15 (60%) and 5 (20%) patients in the femoral and psoas groups, respectively (P = .01). Conclusions: Using a posterior psoas compartment approach to the lumbar plexus does not increase the minimum effective anesthetic concentration of mepivacaine required to block the femoral nerve as compared with the anterior 3-in-1 approach, and provides better quality of intraoperative anesthesia due to the more reliable block of the lateral femoral cutaneous and obturator nerves.
AB - Background and Objectives: To evaluate if psoas compartment block requires a larger concentration of mepivacaine to block the femoral nerve than does an anterior 3-in-1 femoral nerve block. Methods: Forty eight patients undergoing anterior cruciate ligament repair were randomly allocated to receive an anterior 3-in-1 femoral block (femoral group, n = 24) or a posterior psoas compartment block (psoas group, n = 24) with 30 mL of mepivacaine. The concentration of the injected solution was varied for consecutive patients using an up-and-down staircase method (initial concentration: 1%; up-and-down steps: 0.1%). Results: The minimum effective anesthetic concentration of mepivacaine blocking the femoral nerve in 50% of cases (ED50) was 1.06% ± 0.31% (95% confidence interval [CI], 0.45%-1.68%) in the femoral group and 1.03% ± 0.21% (95% CI, 0.6%-1.45%) in the psoas group (P = .83). The lateral femoral cutaneous and obturator nerves were blocked in 4 (16%) and 5 (20%) femoral group patients as compared with 20 (83%) and 19 (80%) psoas group patients (P = .005 and P = .0005, respectively). Intraoperative analgesic supplementation was required by 15 (60%) and 5 (20%) patients in the femoral and psoas groups, respectively (P = .01). Conclusions: Using a posterior psoas compartment approach to the lumbar plexus does not increase the minimum effective anesthetic concentration of mepivacaine required to block the femoral nerve as compared with the anterior 3-in-1 approach, and provides better quality of intraoperative anesthesia due to the more reliable block of the lateral femoral cutaneous and obturator nerves.
KW - Anterior 3-in-1
KW - Anterior cruciate ligament repair
KW - Lumbar plexus block
KW - Mepivacaine
KW - Minimum effective concentration
KW - Posterior psoas compartment
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U2 - 10.1016/j.rapm.2007.07.008
DO - 10.1016/j.rapm.2007.07.008
M3 - Article
C2 - 18155051
AN - SCOPUS:37249002888
VL - 33
SP - 10
EP - 16
JO - Regional Anesthesia and Pain Medicine
JF - Regional Anesthesia and Pain Medicine
SN - 1098-7339
IS - 1
ER -