ABSTRACT
Oxygen consumption, tidal volume, and minute volume decreased in 20 patients during the first stage of labor after either epidural or paracervical block. The elimination of pain with optimum regional analgesia is associated with a decrease in tidal and minute volumes, apprehension, and consequently a decreased oxygen consumption. These factors may contribute to a decrease in maternal lactic acidosis during labor.
Subject(s)
Anesthesia, Epidural/adverse effects , Anesthesia, Obstetrical/adverse effects , Cesarean Section/methods , Nerve Block/adverse effects , Oxygen Consumption , Adult , Female , Humans , Pain , Pregnancy , Respiratory Function TestsABSTRACT
Lidocaine concentrations were measured after vaginal delivery or Caesarean section with epidural anaesthesia in samples of maternal and umbilical blood and in newborn gastric contents. The pH of the gastric aspirate was also determined in a number of neonates. Gastric lidocaine concentrations were higher and the pH was lower after vaginal delivery in comparison to Caesarean section. A significant inverse correlation exists between gastric pH and gastric lidocaine concentration, Neonate gastric lidocaine concentration was significantly higher than in maternal or umbilical venous plasma after vaginal delivery, but not after Caesarean section. Due to these differences, gastric lavage for the treatment of neonatal lidocaine intoxication may be more beneficial in reducing foetal systemic local anaesthetic concentration after vaginal than after elective abdominal delivery.
