Transversus abdominis plane block with 0.25 % levobupivacaine: a prospective, randomized, double-blinded clinical study.
OBJECTIVE
Because blood concentrations of local anesthetics sometimes reach toxic levels after transversus abdominis plane (TAP) block, reduction of the dose has been necessary to reduce the risk of systemic toxicity. We therefore investigated the effects of TAP block with 0.25 % levobupivacaine (100 mg) on postoperative pain and measured its plasma concentration after gynecological surgery.


METHODS
Forty women undergoing elective open gynecological surgery were randomized to receive bilateral TAP block with 20 ml 0.25 % levobupivacaine on each side (TAP group) or not (non-TAP group) before surgery. Postoperative pain was treated with intravenous patient-controlled analgesia by use of morphine. Patients were evaluated 3 and 24 h after the end of surgery. Visual analog scale (VAS) for pain at rest and with movement, and morphine consumption were recorded. Plasma concentrations of levobupivacaine after TAP block were measured.


RESULTS
Three hours after surgery, total morphine consumption was significantly lower in the TAP group (2.8 ± 1.6 mg) than in the non-TAP group (6.4 ± 4.8 mg, P = 0.03). There were no significant differences between VAS in the two groups. Mean plasma concentration of levobupivacaine peaked 10 min after TAP block (0.99 ± 0.43 μg/ml), and the highest concentration was 1.99 μg/ml.


CONCLUSIONS
TAP block with 100 mg levobupivacaine is a safe and efficacious multimodal analgesic regimen for postoperative pain after open gynecological surgery.
Department of Anesthesiology and Resuscitology, Shinshu University School of Medicine, 3-1-1, Asahi, Matsumoto, Nagano, 390-8621, Japan, tisd@shinshu-u.ac.jp.
Takashi
T
Ishida
Akiyuki
A
Sakamoto
Hidenori
H
Tanaka
Susumu
S
Ide
Kumiko
K
Ishida
Satoshi
S
Tanaka
Teruyo
T
Mori
Mikito
M
Kawamata
D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled / Q000009:adverse effects / Q000379:methods; D000701:Analgesics, Opioid / Q000008:administration & dosage; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002045:Bupivacaine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D017558:Elective Surgical Procedures / Q000379:methods; D005260:Female; D006801:Humans; D000077554:Levobupivacaine; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage; D009407:Nerve Block / Q000009:adverse effects / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D011446:Prospective Studies
D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D009020:Morphine; D000077554:Levobupivacaine; D002045:Bupivacaine