The Use of GC-MS in Perinatal Pharmacology: The Metabolism and Pharmacokinetics of Analgesic Drugs in Mothers and Their Babies

Abstract

Most mothers nowadays demand effective relief of pain during labour, and it is important that the safety of such analgesic procedures be evaluated from the maternal and neonatal viewpoints. The ideal analgesic drug would not influence maternal consciousness and co-operation during childbirth and would have no effect on the neonate. Obstetric analgesis is generally achieved either with powerful narcotic drugs, particularly pethidine, or by lumbar epidural anaesthesia. In this procedure, a long acting local anaesthetic is injected into the epidural space around the spinal cord, thereby anaesthetizing the lower part of the body. The drug of choice for this at present is bupivacaine. Table 1 lists the analgesic procedures used for the 845 deliveries during the year 1976 at St. Mary’s Hospital, London and shows that some 70% of mothers opted for one of the above treatments, compared with less than 20% who had no analgesic drugs.