A comparison of post-incisional subcutaneous, intramuscular, and subcutaneous plus intramuscular infiltrations of lidocaine in post-caesarean section pain control

Abstract

Background. How best to relieve pain after caesarean section (CS) is still debated by many obstetricians. Pre- and post-incisional infiltrations with local anaesthetics have been widely tested and compared. However, the effect of the site of post-incisional infiltration with a local anaesthetic on the quality of pain reduction is not well documented. Objectives. To compare the effects of post-incisional infiltration of lidocaine into the subcutaneous tissue, rectus abdominis, or both subcutaneous tissue and rectus abdominis on pain after CS. Methods. Two hundred candidates for elective CS were randomly allocated to four matched groups of equal size. They received post-incisional infiltration of either 1% lidocaine (in the rectus abdominis, the subcutaneous tissue, or both) or saline. The pain intensity and analgesic demand after CS, as well as the time to ambulation and breastfeeding, were documented and compared between the groups. Results. Post-CS pain intensity and analgesic demand were significantly lower, and the time to ambulation was significantly less, in the lidocaine groups than in the placebo group. The time to breastfeeding, however, was comparable between the two groups. Among the patients who received lidocaine, the site of infiltration was associated with no significant differences in terms of post-CS pain intensity and need for analgesics, or time to ambulation and breastfeeding. Conclusion. The site of post-incisional local wound infiltration with lidocaine is not a clinically important factor in pain relief after CS.