How to learn beadside skills
And now I'm going to tell you exactly how to learn bedside skills. There are several simple rules and if you follow them you will learn the "Big 12" and you will become accomplished at the bedside cardiovascular examination.
Rule number one, have an orderly approach. Dr. Harvey has popularized the 5-finger approach, and for the bedside examination those five fingers are the appearance of the patient, assessing the carotid arterial pulse, the venous pulse, chest wall movement and auscultation, and we shall emphasize auscultation and use the other fingers as backup to put it all in perspective.
The second very important thing is memorize something. Don't memorize anything else in cardiology, but do memorize the pressure and the volume curves. If you understand the pressure and the volume curves, you will understand why the heart sounds occur and why blood is flowing. For example, [sound] the first heart sound. Why? Because the pressure rises higher in the left ventricle than it is in the left atrium. [sound] Why the second heart sound? Because the pressure falls lower in the left ventricle than in the aortic root. And we're going to review those carefully.
Flow. Remember this rule, that during the first 1/3 of systole 2/3 of blood leaves the heart and during the first 1/3 of diastole 2/3 of blood fills the heart. So, if you have events due to flow alone, they will occur either early in systole or early in diastole.
The next very important thing is practice, practice, practice. On patients ideally, but in the absence of patients, it has been proven that simulation techniques, Harvey, heart sound tapes, heart sound simulators will teach you heart sounds and will teach you heart murmurs. And when these skills are learned on a simulator, they can be transferred to real patients. In some ways, simulators are a benefit, because they take out the background noise that can occur in a very complex patient, and you can focus, you can focus.
The next very important thing is to involve yourself with mimicry, and we're going to practice that together. If you mimic those heart sounds, you will start thinking about the hemodynamics and the pathophysiology.
It's very important, it's the world's least expensive system of simulation.
And finally, test yourself, test yourself on patients, on heart sound tapes, on simulators, any way you can. Education is driven by testing. Test yourself and then take all of what you've learned and transfer it to the patient and practice, practice, practice.
Five Fingers of cardiac examination
To review again, the five fingers of the cardiovascular bedside, or physical, examination include the evaluation of the patient's general appearance, venous pulse, arterial pulse, precordial movement and auscultation. Ausculation will be emphasized in this program.
Left heart pressure curves
Left ventricular systole begins with the first heart sound, or S1. It occurs as the pressure in the left ventricle rises above that of the left atrium. The mitral valve closes and the sound occurs as the valve leaflets stretch and become tense. The first heart sound occurs just before the carotid impulse and is loudest at the apex. As left ventricular pressure continues to rise above aortic pressure, the aortic valve opens. Normally, no sound is produced by valve opening. Systole ends and diastole begins with the second heart sound, or S2. It occurs as left ventricular pressure falls below that of the aortic root. The aortic valve closes and the sound occurs as the valve leaflets stretch and become tense. The second sound occurs at the end of the carotid impulse and is loudest at the base. As left ventricular pressure falls below left atrial pressure, the mitral valve opens, a normally inaudible event.
Left ventricular volume curve
Cardiac blood flow is maximal in early systole and early diastole. Approximately two-thirds of the blood ejected leaves the ventricles in the first one-third of systole; and two-thirds of the blood filling the ventricles enters during the first one-third of diastole. This information is useful when analyzing the significance of certain auscultatory events.
Problem solving at multiple levels
When you recognize a finding during your cardiovascular examination you begin a problem solving process at multiple levels. First, you demonstrate the skill to identify the finding. Next, you begin to interpret the pathophysiology associated with that finding and that leads you to define a differential diagnosis and estimate severity. Finally, you may be able to make a management decision by correlating the bedside finding with other available clinical information.