Anaesthesia for caesarean section (epidural and general): effects on the neonate

Anaesthesia may impair the condition of the neonate either directly (largely mechanically in utero or due to the influence of drugs) or indirectly via alteration of placental perfusion. These influences may further differ during normal caesarean section from those under complicated conditions. The criteria with which neonatal conditions are estimated need to be carefully distinguished with respect to results obtained. Neurobehavioural test results may give different information to the observer. A variety of drugs, not simply one, is used during general anaesthesia (GA). Even the consequences of maternal stress-fetal and neonatal levels of catecholamines or endogenous peptides may play a role. Local anaesthetics are known to cross the placenta as general anaesthetics do; in most cases, their effects are clinically irrelevant. Fetal and neonatal deliterious effects of regional anaesthesia (RA) are mainly related to maternal hypotension and the administration of large doses of local anaesthetics. If adequate doses of local anaesthetics and/or opioids are used, alterations in neurobehavioural scores are subtle and transient. Under normal maternal and fetal conditions, GA and RA are almost identically useful with respect to neonatal well being after caesarean section; subtle and inconsistent neurobehavioral residua may be present for a short period of time following GA. Under conditions of a compromised fetus, the neonate may however benefit from epidural anaesthesia more than from GA.