A pulse gives you three findings at once and only one of them is a number. Decide how each patient’s pulse must be counted, find the nine sites and know what each is for, grade amplitude on the 0 to 4+ scale, and measure a pulse deficit the way it actually has to be measured — two nurses, one watch, sixty seconds.
How would you count this pulse?
Count for 30 seconds and multiply by two only if the rhythm is regular. Count a full 60 seconds if the rhythm is irregular, the rate is very fast or very slow, the patient is an infant, or you are taking an apical pulse.
Where the pulses are
Select a site to see where it lies and what it is for. Palpate with the pads of the index and middle fingers, never the thumb — the thumb has a pulse of its own that you will happily count as the patient’s.
Grade what your fingers found
Amplitude is the force of the pressure wave, graded 0 to 4+. Some facilities use a 0 to 3+ scale — know which one your chart uses before you document a number. Press gently: heavy pressure occludes the vessel and erases the very finding you are grading.
Calculate a pulse deficit
A pulse deficit is the apical rate minus the radial rate. It exists because some ventricular contractions are too weak, or come too soon after the last one, to fill enough to generate a palpable peripheral wave. You hear them at the apex; the wrist never feels them.
How did you measure it?
Tick everything that was true. The technique decides whether the number means anything.
Counting, and what it costs to get it wrong
Pick a patient, then choose how you would count.
Doubling an irregular 30-second count is how a real rate of 96 becomes a charted 120. In an irregular rhythm the beats are not evenly spread, so whichever half-minute you happened to catch is not half of the minute. There is no shortcut: irregular means sixty seconds, and it means the apex.
Report all three, every time.Rate against the expected 60–100 in adults, adjusted for age and for this patient’s own baseline — an endurance athlete at 48 and a patient on a beta-blocker at 56 may be entirely normal, while 56 in a patient whose baseline is 88 is a change worth investigating. Rhythm: regular, regularly irregular (a repeating pattern, such as every third beat dropped), or irregularly irregular (no pattern at all — the classic finding of atrial fibrillation). Amplitude on the 0 to 4+ scale.
Take an apical pulse when
The patient is an infant or child under 2 · the rhythm is irregular · you are about to give digoxin or another rate-controlling drug · the peripheral pulse is difficult to feel. Auscultate with the diaphragm at the point of maximal impulse — fifth intercostal space, left midclavicular line in an adult. Each “lub-dub” is one beat. In infants the point of maximal impulse sits higher and more lateral — third or fourth intercostal space, at or just lateral to the midclavicular line — because the heart lies more horizontally in the chest.
Pulse sites
The carotid deserves respect. Palpate one side only, and gently. Bilateral or heavy pressure can trigger a vagal response and bradycardia in a patient who is already unwell. It is the last pulse to disappear in shock, which is exactly why it is the one you reach for in an arrest.
Absent does not always mean occluded. The dorsalis pedis is congenitally absent in up to 10 percent of healthy people, so compare sides and mark the spot where you found it with a skin pen so the next nurse looks in the right place. A new absent pulse in a limb that was previously perfused is a different animal entirely — that is an emergency.
Perfusion is not a colour test. Pallor, cyanosis and mottling are unreliable on brown and black skin. Assess the limb by comparing it with the other side, palpating temperature with the dorsum of your hand, checking capillary refill at the nail beds, and inspecting the palms, soles, conjunctivae and oral mucosa, where a grey or ashen dullness is readable on every skin tone. Take the patient’s report of pain, numbness or coldness as a finding in its own right.
The 0 to 4+ scale
Assign a grade to each description, then press Check my grades.
Never chart a zero from your fingers alone. Confirm with a Doppler before you document an absent pulse, and document whether the signal was present by Doppler only. A new absent pulse suggests arterial occlusion, severe shock or compartment syndrome — it is an emergency, and in a cold painful limb you do not elevate the limb while you call.
Two qualities worth recognising early.Pulsus paradoxus is an exaggerated fall in systolic pressure — more than 10 mm Hg — during inspiration; the peripheral pulse seems to fade with each breath in. It points toward cardiac tamponade, severe asthma or constrictive pericarditis and warrants immediate escalation. Pulsus alternans alternates strong and weak beats at a regular rhythm and suggests severe left ventricular dysfunction.
The deficit, and whether it can be believed
—beats/min not reaching the wrist
Enter both rates, tick the technique you used, then press Calculate and audit.
Pearl. A widening pulse deficit on serial checks means fewer beats are perfusing the body even if the apical rate looks stable. Report the trend, not just today’s number.
Why the deficit exists
The classic causes are atrial fibrillation and frequent premature ventricular contractions. A contraction that arrives too soon after the last one has not had time to fill, so it ejects too small a stroke volume to send a palpable wave to the wrist — but it still makes a sound at the apex. The size of the deficit is a rough measure of how much of the heart’s work is being wasted.