Regional Anesthesia and Pain Control
J.R. KLEIN, J.P. HEATON, J.P. THOMPSON, B.R. COTTON, A.C. DAVIDSON AND G. SMITH
University Department of Anaesthesia and Department of Obstetrics and Gynaecology, Leicester Royal Infirmary, Leicester, United Kingdom
Br. J. Anaesth., 84: 248–249, 2000
Some studies have shown that administration of local anesthetics into the wound during closure of surgical operations produces significant analgesia and is associated with a reduction in postoperative analgesic requirements. Others have shown no effect of this procedure on morphine requirements or pain score. This double-blind, randomized study was designed to establish if infiltration of the deep and superficial layers of the wound of a Pfannenstiel incision with bupivacaine after total abdominal hysterectomy had an opioid-sparing effect. Outcome measures were total opioid consumption using patient-controlled analgesia (PCA) and visual analog scores for pain, sedation, and nausea.
The 40 women, aged 20 to 60 yr, were undergoing total abdominal hysterectomy for nonmalignant disease. Patients received wound infiltration with 40 mL of 0.9% normal saline or 40 mL of 0.25% bupivacaine with epinephrine 1:200,000. Patients had a PCA device set to deliver morphine in 1-mg boluses with a 5-min lockout. Pain scores were recorded by the patient using a 100-mm linear visual analog score at 8, 12, 24, 36, and 48 hr.
The two groups were comparable in age, weight, and height. There were no significant differences in any variable, including duration of surgery. No significant difference was noted in morphine consumption during the first or second 24-hr period after operation and no significant difference in pain scores were seen at rest or on movement. Nausea and sedation scores did not differ between the two groups.
Infiltrating the subcutaneous and muscular layers with local anesthetic did not reduce PCA morphine consumption or pain scores in these women. This may be because deeper structures are responsible for the pain. Other methods of analgesia such as intraperitoneal infiltration with local anesthetics or adjuvant use of nonsteroidal anti-inflammatory drugs may be more effective.
Infiltration of the abdominal wall with local anesthetic after total abdominal hysterectomy resulted in no opioid-sparing effects in this study. This negative result may be related to the sample size of only 40 patients. The large intragroup differences may not allow one to see any statistical differences between the two groups.
Ferne B. Sevarino M.D.