Plasma arginine vasopressin response to water load during labor

Abstract

To find out whether plasma vasopressin (PAVP) response to a water load during pregnancy is inappropriately high, as had been speculated, we measured PAVP by radioimmunoassay in 30 women at the time of delivery. Ten women had received infusion of aqueous glucose solution during labor for hydration (GW group); another ten received infusion of glucose solution as a vehicle for oxytocin (OT group), and ten women did not receive any intrapartum intravenous fluid therapy (controls). Serum sodium and osmolality were also determined in all the subjects. PAVP levels were significantly lower in GW (0.70 +/- 0.4 pg/ml) and OT groups (0.7 +/- 0.6 pg/ml) (P less than 0.05). Significant negative correlation was seen between the amount of glucose solution infused and levels of PAVP (r = -0.66; P less than 0.01), while a significant positive correlation was seen between PAVP and serum sodium (r = 0.61; P less than 0.01). These findings suggest that during labor, the physiological relationship between serum osmolality and PAVP is intact, and that infusion of a water load in the form of aqueous glucose solution is attended by an expected lowering of PAVP. We infer that inappropriate ADH response is not the cause of water retention and hyponatremia often seen in women receiving aqueous glucose solution during labor.

Hyponatremia complicating labour—rare or unrecognised? A prospective observational study

“…Typically, this may occur postoperatively, but during labour stimuli for vasopressin release are abundant. Labour itself is, however, not a situation causing inappropriate vasopressin secretion 22. The women in our study received fluid volumes well below their predicted maximum capacity of renal excretion at rest; therefore, the development of hyponatraemia indicates increased vasopressin activity during labour.…”

“…Labour itself is, however, not a situation causing inappropriate vasopressin secretion. 22 The women in our study received fluid volumes well below their predicted maximum capacity of renal excretion at rest; therefore, the development of hyponatraemia indicates increased vasopressin activity during labour. Our results indicate that fluid volume is the major determinant of hyponatraemia, but the antidiuretic effects of endogenous vasopressin and oxytocin administration increase the susceptibility of women to develop hyponatraemia during labour.…”

Uterine Contraction Parameters Before and During the Pre-Epidural Fluid Bolus: A Pilot Study

“…Furthermore, research demonstrated a significant decrease in plasma vasopressin levels at 15 and 45 min of immersion to the chest in parturients at term gestation (Benfield et al, 2010). Similarly, vasopressin levels were significantly lower in parturients who received an infusion of a glucose solution compared to those who only sipped oral fluids (Singhi & Parshad, 1985). Conversely, vasopressin levels were elevated in women with primary dysmenorrhea (Stromberg, Åkerlund, Forsling, Granström, & Kindahl, 1984).…”