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Ultrasound echocardiography is an operator‐dependent hemodynamic assessment, which is a quick and non‐invasive measurement tool. Its effectiveness has not yet been proven in randomized clinical trials.

Cardiac function and anatomy can be assessed using five standard views (Table 11.2).

 Stroke volume can be estimated with echocardiography:SV = π × R2 × velocity time interval (VTI) of the left ventricular outflow tract (LVOT) (R= radius of LVOT in cm).Parasternal long axis view is used to measure diameter of the LVOT.Apical five chamber view is used to measure the VTI with pulsed Doppler.

 Routine measurements of the size of the IVC and collapsibility with respiration can be used to estimate right atrial pressure (RAP) and fluid responsiveness in patients via the subcostal view on echocardiography.

Size ≤2.1 cm, collapses >50% during inspiration = RAP 0–5 mmHg.

Size >2.1 cm, collapses >50% during inspiration = RAP 5–10 mmHg.

Size >2.1 cm, collapses <50% during inspiration = RAP 10–20 mmHg.

Table 11.2 Echocardiography views.

View	Findings
Parasternal long axis	Pericardial effusion, LV/RV size and function, septal kinetics
Parasternal short axis	Pericardial effusion, LV/RV size and function, septal kinetics
Apical four chamber	Pericardial effusion, LV/RV size and function
Subcostal four chamber	LV/RV size and function, preferred view in cardiac arrest
Inferior vena cava longitudinal view	Determine preload sensitivity