[Nitroglycerin to relax the uterus during cesarean delivery for the low birthweight baby]

The uterus at premature birth being thick and sensitive, we applied nitroglycerin (NTG) to relax the uterus during cesarean delivery for the low birthweight baby.

Twelve parturients of impending premature birth and nine of severe intoxication were included. General anesthesia was induced with thiamylal, and maintained with 5% inhaled sevoflurane. NTG was injected in an intermittent dose of 500 microg. The relative hardness of the uterus at delivery was evaluated by obstetricians in four ranks of categories.

The mean gestation period was 27.4 weeks (24 weeks at the minimum-33 weeks at the maximum) and the mean birthweight was 986 g (561-1518 g). The mean time elapsed from induction of anesthesia to delivery was 8.3 min (2-14 min) while NTG was injected for the mean 1.8 times that reflected a total dose of 900 microg (500-1500 microg). The mean endtidal concentration of sevoflurane at delivery reached 3.8% (3.4-4.3%). The uterus was evaluated as "very soft" in 15 out of 21 cases, and all babies were extracted easily without injury through the lower J-shaped section of the uterus. The mean Apgar score was 2.9 points at 1 minute and 6.3 points at 5 minutes. No adverse effect of NTG on the mothers or babies was noticed.

NTG relaxes the uterus effectively and facilitates cesarean delivery for the low birthweight baby.