1. Protamine-induced hypotension in heart operations: Application of the concept of ventricular-arterial coupling 
Masahiro Oe, MD, Toshihide Asou, MD, Shigeki Morita, MD, Hisataka Yasui, MD, Kouichi Tokunaga, MD 
The Journal of Thoracic and Cardiovascular Surgery 
Volume 112, Issue 2, Pages (August 1996)
DOI: /S (96)70274-X
Copyright © 1996 Mosby, Inc. Terms and Conditions

2. Fig. 1
Principle used to assess Ees and Ea from a single ejecting beat. Left panel: Estimation of Pmax. The solid line shows a measured ejecting beat. The left ventricle was assumed as a linear time varying hydromotive pressure source, HMP(t). By fitting the isovolumic contraction portion of the measured left ventricular pressure (LVP) to the function described at the bottom of the figure (equation 1), estimated isovolumic LVP (dashed line) and Pmax were obtained. Right panel: Estimation of Ees and Ea. The line connecting the estimated Pmax point to the left upper corner (Pes) of the pressure-ejected volume loop that was obtained by integration of aortic flow yields the slope of ESPVR (Ees) and Ve (Ved - V0). Ea is the slope of the Pes-SV relationship.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /S (96)70274-X)
Copyright © 1996 Mosby, Inc. Terms and Conditions

3. Fig. 2
Representative changes of hemodynamic parameters during protamine-induced hypotension in a beat-to-beat fashion.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /S (96)70274-X)
Copyright © 1996 Mosby, Inc. Terms and Conditions

4. Fig. 3
Changes of hemodynamic parameters during protamine-induced hypotension. Results are shown for each point with averaged raw data for each of the 21 patients.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /S (96)70274-X)
Copyright © 1996 Mosby, Inc. Terms and Conditions

5. Fig. 4
Relationships between percentage changes from each control value in MAP (%MAP) and changes in Ea (%E a), Ees (%E es ), SVR (%SVR), or Ve (%V e ) during protamine-induced hypotension. %MAP had significant correlations with %SVR (dashed line; y = 0.55x , r = 0.74, p < 0.001, standard error of the estimate 5.7%) and with %Ea (dashed line; y = 0.47x , r = 0.60, p < 0.001, standard error of the estimate 7.5%). Neither %Ees nor %Ve had any significant correlation with %MAP.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /S (96)70274-X)
Copyright © 1996 Mosby, Inc. Terms and Conditions

6. Fig. 5
Left panel: Bar graph showing decreased MAP at midpoint and maximum during protamine-induced hypotension. Right panel: Bar graph showing effect of each parameter on the change in Pes. ΔPes describes the effect of a change in a parameter on the Pes, provided that the other two parameters remain at their control values.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /S (96)70274-X)
Copyright © 1996 Mosby, Inc. Terms and Conditions