our study aim to assess the validity of using mini fluid challenge to assess the volaemic status of patients after liver transplantation

After approval of institutional ethical committee and after informed patient consent, patients fulfilling criteria will be involved. Upon ICU admission, patients will be connected to full monitoring and confirming patient hemodynamic stability and no active bleeding through drains. Patients will be in supine position and baseline readings will be recorded. Fluid responsiveness will be assessed with mini fluid challenge by 150 ml of albumin 5% given over 1 minute. After fluid administration stroke volume (SV) assessed by trans thoracic echo (TTE) and other hemodynamic parameters will be recorded. Remaining 350 ml of albumin 5% will be continued over 14 minute to have total volume given 500 ml. after fluid administration SV and other parameters will be recorded. The fluid challenge will be given intravenously via a specific wide pore venous line. Fluid responsiveness will be defined as an increase in the SV by 15% after the infusion of fluid.

TT Echo Examination:

A single LVOT diameter will be measured for each patient as the distance between the inflection points at the base of the aortic valve cusps from the left parasternal long axis view during systole.

Assuming a circular cross section, the LVOT area will be calculated from the LVOT diameter as:

π X (LVOT diameter/ 2)2 = (LVOT diameter)2 X 0.785 Pulse wave Doppler sampling cursor will be placed in the middle of the LVOT immediately proximal to the aortic valve in 5 chamber apical view.

The sonographer manually will trace the velocity-time envelope (VTI). SV values will be calculated by multiplying VTI by cross sectional area.

Inclusion Criteria:

• Patients post liver transplantation.
• ASA III- IV
• Age > 18 years

Exclusion Criteria:

• Age less than 18 years.
• Patient with fulminant liver failure.