Randomized trial of intermittent or continuous amnioinfusion for variable decelerations.

OBJECTIVE: To determine whether continuous or intermittent bolus amnioinfusion is more effective in relieving variable decelerations. METHODS: Patients with repetitive variable decelerations were randomized to an intermittent bolus or continuous amnioinfusion. The intermittent bolus infusion group received boluses of 500 mL of normal saline, each over 30 minutes, with boluses repeated if variable decelerations recurred. The continuous infusion group received a bolus infusion of 500 mL of normal saline over 30 minutes and then 3 mL per minute until delivery occurred. The ability of the amnioinfusion to abolish variable decelerations was analyzed, as were maternal demographic and pregnancy outcome variables. Power analysis indicated that 64 patients would be required. RESULTS: Thirty-five patients were randomized to intermittent infusion and 30 to continuous infusion. There were no differences between groups in terms of maternal demographics, gestational age, delivery mode, neonatal outcome, median time to resolution of variable decelerations, or the number of times variable decelerations recurred. The median volume infused in the intermittent infusion group (500 mL) was significantly less than that in the continuous infusion group (905 mL, P =.003). CONCLUSION: Intermittent bolus amnioinfusion is as effective as continuous infusion in relieving variable decelerations in labor. Further investigation is necessary to determine whether either of these techniques is associated with increased occurrence of rare complications such as cord prolapse or uterine rupture.

Leucocytozoonosis in Canada geese at the Seney National Wildlife Refuge.

A history is given of the Seney National Wildlife Refuge and the losses of goslings of Canada geese (Branta canadensis) recorded since inception of the refuge in 1935. Since 1960, when more reliable data became available, losses have been estensive every 4 years. Goslings deaths are attributed to the infection with Leucocytozoon simondi. The blackfly (Simulium innocens) is considered to be the prime vector in the transmission of this blood parasite to goslings.

Fluorescent-antibody studies of haplosporidian parasites of oysters in Chesapeake and Delaware bays.

A fluorescent antibody was produced against a plasmodial oyster parasite thought to be a haplosporidian, Minchinia nelsoni, which was termed MSX. The antibody reacted with this type of plasmodia from oysters, Crassostrea virginica ( Gmelin), from all sources, and it also reacted with its sporulating and spore stages. This reaction indicates cospecificity of the stages. No reaction occurred with any stage of another oyster haplosporidian, Minchinia costalis, indi- cating that the M. nelsoni and the M. costalis are antigenically distinct species.