Pearls for the Developing Clinician: Taking a Pulse

This is the first installment of a column to which I will return periodically over the next few years, with learning points I come upon in my own training or in conversation with my clinical mentors.

Today’s lesson: Practice taking pulses manually on your patients, so it comes naturally when you have no special tools at your disposal.

The Case Study

A 56-year-old Indian man was driving a car through the desert on a hot day with his wife, who happens to be a physician. He mentioned vague abdominal discomfort of moderate intensity that had been present for about half an hour, but chalked it up to indigestion from too much restaurant food.

After several more minutes, the man began feeling nauseated, pulled the car over, vomited a small amount of non-bilious, non-bloody emesis, and asked his wife to drive.

He agreed he felt tired, but denied any pain and reported partial relief of symptoms after vomiting. He felt a little light-headed, but he thought he might be dehydrated, because of  the heat. They traded positions, and he reclined in the passenger seat to rest.

What sorts of things should the physician think about before driving on?

The woman looked carefully at her husband and considered his general appearance, taking into consideration his medical history, which was remarkable for a 25-pack history of cigarette smoking and a childhood bout of rheumatic fever without any known sequelae of the heart valves.

She knew symptoms like this were not typical for him and that he had no known history of pulmonary or gastrointestinal disorders. She noticed a small amount of sweat on his forehead and that his skin, normally a deep brown color, had a somewhat pale quality to it.

His work of breathing was normal, he was alert and able to speak in complete sentences, and he had no lateralizing signs, peripheral edema (swelling) or distension of his neck veins.

Before driving on, the woman took his wrists and felt his radial pulses, which were symmetric but weak, irregularly irregular (a sign of atrial fibrillation), and beating at a rate of over 200 beats per minute (suggesting the heart was not able to pump efficiently, due to decreased filling time between beats).

She immediately called 911, and the man was taken to the nearest hospital by ambulance, where he was found to have an acute myocardial infarction (heart attack) that was subsequently treated with four-vessel bypass grafting.

Especially in older male smokers, acute coronary syndrome (blockage of the arteries that supply the heart) should be considered with any acute symptoms near the trunk. The classic presentation is chest pain or tightness radiating to the left jaw or shoulder, but some people will have jaw or shoulder pain without any chest symptoms, and others still will have no pain whatsoever.

The range of presentations of acute myocardial infarction include vague abdominal discomfort, nausea, vomiting, cough, diaphoresis (sweating), fatigue, light-headedness and/or fainting, or increased work of breathing.

Other things to consider in someone with vague abdominal pain include an aortic aneurysm that has torn, inflammation of the stomach or intestines (with or without ulceration), appendicitis, diseases of the biliary tree (either related to gallstones or not), liver disease, pancreatic disease, as well as infectious gastroenteritis, acid reflux or functional dyspepsia (tummy ache — not otherwise specified).

Taking Pulses Manually

In 1985, the Advanced Trauma Life Support (ATLS) handbook included a set of guidelines to estimate systolic blood pressure in the setting of acute blood loss, based on the presence or absence of carotid, femoral and radial pulses.

There has been significant debate about these guidelines, with a series of letters and articles in the British Medical Journal around the year 2000 criticizing the ATLS handbook for making numerical estimates without solid evidence, citing studies with significant variation in blood pressure, despite identical pulse findings.

I believe the result of that discussion was that whether or not feeling pulses predicts a numerical value in one person compared to another, it certainly can be followed in one person over time, especially when associated with any changes in symptoms, mental status and the overall clinical picture.

By taking this man’s radial pulses and speaking with him, the physician in the case above was able to tell he was in an abnormal heart rhythm but that his brain was still getting enough oxygen to maintain his mental status at that point. She knew a medical response was necessary but that CPR need not be started.

Had his pulses been asymmetric, she might have been more concerned about disease process in the vasculature, and if he had had peripheral edema, distended neck veins or increased work of breathing, she may have been concerned that his heart was not able to move blood forward at a rate that kept up with what it received from the veins.

From very early in a developing clinician’s training today, heart rates are measured by assistants, determined by pulse oximeters or by automated blood pressure cuffs. For this reason, the vascular exam is often abbreviated or even skipped by students.

The learning point for the day is that it is useful to take pulses manually on as many patients as you can throughout your training, to get a sense of the range of normal and abnormal in location, timing and quality.

A very easy mistake to make is to push too hard while trying to feel a pulse (especially a weak one), which can lead to feeling your own pulse in your fingers. I find it useful to use to my index and middle finger, slightly compressing the artery proximally (closer to the heart) with one finger and feeling for the pulse with the other.

Whether you are a budding physician, dentist, nurse or pharmacist, take that extra minute to practice this while the stakes are low and you can compare to the automated measurement. In an emergency without any instruments, having faith in your fingers to inform clinical decision-making comes from this fund of experience.