Cardiac output measurement by thoracic electrical bioimpedance in a patient with ovarian hyperstimulation syndrome

A 31-year-old woman developed severe ovarian hyperstimulation syndrome (OHSS) after exogenous gonadotropin stimulation for an in vitro fertilization program. Because of refusal of invasive monitoring, thoracic electrical bioimpedance (TEB) was performed to evaluate cardiac function and volume status. TEB pointed out decreased cardiac output (CO: 4.23 liters/min), cardiac index (CI: 2.63) and stroke volume (SV: 57.5 ml/beat). Serial monitoring of hemodynamic variables was then performed. After the data were obtained, fluid management was performed, and the patient recovered from abnormal homeostasis in 3 days. The hemodynamic variables returned to the normal range (CO: 6.85 liters/min, CI: 4.25, SV: 100.5 ml/beat) within the first 24 h. There were no complications such as life-threatening multiple organ failure. We discuss the usefulness of TEB for the fluid management of severe OHSS, as well as its implications.