Continuous non-invasive hemodynamic monitoring in early onset severe preeclampsia

Objectives: Continuous hemodynamic monitoring offers the opportunity to individualize management in severe preeclampsia (PEC). We compared cardiac output (CO) and total peripheral resistance (TPR) measured by bioreactance (NICOM), Clearsite (TM) Fingercuff [CS), and 3D-echocardiography (3DE). Study design: This prospective observational study included 12 pregnant patients with early PEC. CO and TPR were measured simultaneously by NICOM, CS, and 3DE antepartum and 1-2 days postpartum. Using 3DE as the standard, CS and NICOM interchangeability, precision, accuracy, and correlation were assessed. Results: Compared to 3DE-CO, CS-CO was highly correlated (R-2 = 0.70, p = <0.0001) with low percentage error (PE 29%) which met criteria for interchangeablity. CS-TPR had strong correlation (R-2 = 0.81, p = <0.0001) and low PE (29%). While CS tended to slightly overestimate CO (bias + 2.05 +/- 1.18 L/min, limit of agreement (LOA) -0.20 to 4.31) and underestimate TPR (bias -279 +/- 156 dyes/sec/cm(5); LOA -580 to 18.4) these differences were unlikely to be clinically significant. Thus CS could be interchangeable with 3DE for CO and TPR. NICOM-CO had only moderate correlation with 3DE-CO (R-2 = 0.29, p = 0.01) with high PE (52%) above threshold for interchangeability. NICOM-CO had low mean bias (-1.2 +/- 1.68 L/min) but wide 95% LOA (-4.41 to 2.14) suggesting adequate accuracy but low precision in relation to 3DE-CO. NICOM-TPR had poor correlation with 3DE-TPR (R-2 = 0.32, p = 0.001) with high PE (67%), relatively low mean bias (238 +/- 256), and wide 95% LOA (-655 to 1131). NICOM did not meet the criteria for interchangeable with 3DE for CO and TPR. Conclusions: Clearsite Fingercuff, but not NICOM, has potential to be clinically useful for CO and TPR monitoring in severe preeclampsia.