Box 1 Clinical Stratification of Acute Heart Failure
Green, compensated; yellow, pulmonary congestion with adequate systemic blood flow; orange, no pulmonary congestion but inadequate systemic blood flow; red, pulmonary congestion and inadequate systemic blood flow
Box 2 Verifying the Presence of a Paradoxical Pulse with the Sphygmomanometer
Step 1 Inflation of the sphygmomanometer cuff above the systolic arterial blood pressure
Step 2 Slow deflation of cuff while examiner listens for Korotkoff sounds over the brachial artery
Step 3 Identification of the peak systolic pressure during expiration
Step 4 Further slow deflation of the cuff to identify the blood pressure at which Korotkoff sounds are audible during both inspiration and expiration
If the difference between the two blood pressure levels exceeds 10 mmHg during normal inspiration, a paradoxical pulse is present. A difference in blood pressure levels >20 mmHg is usually only found in pericardial tamponade and severe dynamic hyperinflation (such as in status asthmaticus).
Box 3 Quote by Adolf Jarisch Junior, Austrian Physician and Pharmacologist, 1928
“It was fatal for the development of our understanding of circulation that blood flow is relatively difficult while blood pressure so easy to measure: This is the reason why the sphygmomanometer has gained such a fascinating influence, although most organs do not need blood pressure but flow”.
Box 4 The Valsalva Manoeuvre to Diagnose Left Heart Failure
In selected critically ill patients who are monitored with an arterial line and can hold their breath for at least 5–10 s, the Valsalva manoeuvre can be performed. The physiological blood pressure response to the increase in intrathoracic pressure during the Valsalva manoeuvre is a short increase followed by a gradual fall of arterial blood pressure. With (expiration and) release of intrathoracic pressure, venous return increases leading to an overshoot of the systolic blood pressure. It is the amplitude of this increase of systolic arterial blood pressure after the end of the Valsalva manoeuvre which correlates directly with left ventricular ejection fraction and function.
Box 5 Clinical Signs of Increased Left Ventricular Filling Pressures (LVFP) and Decreased Left Ventricular Ejection Fraction (LVEF)
Box 6 Cardiac Murmurs: Summary of Timing of Murmurs and Associated Heart Lesions