NEUROHORMONAL AND HEMODYNAMIC-CHANGES IN SEVERE CASES OF THE OVARIAN HYPERSTIMULATION SYNDROME

Objective: To evaluate systemic hemodynamics, endogenous vasoactive ne urohormonal factors (renin-angiotensin and sympathetic nervous systems , antidiuretic hormone, atrial natriuretic factor, and renal prostagla ndins), and renal function in the severe ovarian hyperstimulation synd rome. Design: Prospective longitudinal study. Setting: Assisted-reprod uction unit of a tertiary care hospital in Barcelona, Spain. Patients: 31 consecutive patients having in vitro fertilization with developmen t of ascites because of severe ovarian hyperstimulation syndrome. Meas urements: Mean arterial pressure; cardiac output; peripheral vascular resistance; hematocrit concentration; renal function; plasma renin act ivity; plasma aldosterone, norepinephrine, antidiuretic hormone, and a trial natriuretic peptide determinations; and urinary excretion of pro staglandin E(2) and 6-keto-prostaglandin-F-1 were measured during the syndrome and 4 to 5 weeks after recovery (baseline). Results: During t he syndrome, patients showed increased hematocrits (mean of the paired difference, 0.047; 95% CI, 0.029 to 0.064), decreased mean arterial p ressure (-16.6 mm Hg; CI, -19.8 to -13.6), increased cardiac output (2 .6 L/min; CI, 2.13 to 3.17), and reduced peripheral vascular resistanc e (-709 dyne/s.cm(-5); CI, -792 to -627). This was accompanied by mark ed increases of plasma renin (14.4 ng/L.s; CI, 9.87 to 18.90), norepin ephrine (1.857 nmol/L; CI, 0.533 to 3.161), antidiuretic hormone (3.3 pg/mL; CI, 1.89 to 4.71), and atrial natriuretic peptide levels (9.7 f mol/mL; CI, 6.1 to 13.2). Hemoconcentration developed in 16 patients ( mean of the paired difference in hematocrit concentration, 0.082; CI, 0.063 to 0.101) but not in 15 others (0.009; CI, 0.003 to 0.021). Both groups showed similar values for arterial pressure, cardiac output, a nd peripheral vascular resistance, but patients with hemoconcentration had higher (P < 0.05) levels of renin (mean, 20.97 ng/L.s [CI, 13.3 t o 28.63] compared with 7.83 ng/L.s [CI, 4.08 to 11.58]), norepinephrin e (3.907 nmol/L [CI, 3.057 to 4.757] compared with 2.417 [CI, 2.035 to 2.799]), and antidiuretic hormone (6.0 pg/mL [CI, 4.1 to 7.9] compare d with 2.4 [CI, 1.7 to 3.03]). Conclusions: In addition to increased c apillary permeability, severe ovarian hyperstimulation syndrome is con sistently associated with arteriolar vasodilation. The simultaneous oc currence of these disorders leads to hyperdynamic circulatory dysfunct ion with marked stimulation of the sympathetic nervous system, renin-a ngiotensin system, and antidiuretic hormone.