GASTRO INTESTINAL SYSTEM IN PREGNANCY

Increased intra-abdominal pressure by the gravid uterus,
displacement of the gastric axis and progesterone mediated
reduction in lower oesophageal sphincter tone cause gastro-
oesophageal reflux in as many as 80% of term parturients.
Whilst pregnancy does not seem to cause increased gastric
volumes and delayed gastric emptying, both of these are
features of labour. The administraion of opioids for labour
analgesia further accentuates this. Pregnant women are
therefore at risk of developing Mendelson’s syndrome
(aspiration pneumonitis) especially on induction of general
anaesthesia, which reduces upper oesophageal sphincter
pressure. Strategies for the prevention of this may include
the administration of H
2
blocking drugs, neutralization of
gastric contents with non-particulate antacids, e.g. sodium
citrate, and the use of a rapid sequence induction with
cricoid pressure, when administering general anaesthesia
to pregnant women. At 24 - 48 hours postpartum the
changes in the gastro-intestinal system are thought to have
reverted to norma