MedSchool: Ace Your OSCEsThe Medical Company
GET - On the App Store
Renal Exam
Renal Exam

Radial Pulse

November 28th, 2019

Heart Rate

  • How to Measure

  • Count the number of beats over 15, 30 or 60 seconds and multiply to estimate beats per minute.
    • Normal Range

    • 60 - 100bpm
  • Causes of Bradycardia (

  • Physiological - high cardiac fitness
  • Beta blockers
  • Hypothyroidism
  • Raised intracranial pressure
  • Heart block
  • Sick sinus syndrome
  • Causes of Tachycardia (>100bpm)

  • Sinus tachycardia - physical exertion, infection, anxiety, thyrotoxicosis, stimulant drugs, shock
  • Atrial fibrillation / flutter - aberrant conduction, parenchymal damage
  • Supraventricular tachycardia - aberrant conduction pathways/ re-entry


  • How to Assess

  • Feel the pulse for at least thirty seconds and determine whether the beats fall in time or are irregular.
  • Interpretation

  • Regular: sinus rhythm
  • Sinus arrhythmia: rhythmic variations in vagal tone with respiration
  • Regularly irregular (regular heart rate with occasional missed or extra beats): second degree heart block, premature ventricular contractions
  • Irregularly irregular: atrial fibrillation


Weak pulseAtherosclerosis, tamponade, LV failure, cervical rib, aortic dissection, dehydration
Strong pulseExercise, pregnancy, anxiety, fever, hyperthyroidism, acute alcoholism
Waterhammer / collapsing pulse: strong pulse with sudden drop in intensity following its peakAortic regurgitation, patent ductus arteriosus
Pulsus alternans: regular alternation between strong and weak beats, especially palpated in peripheral arteriesLeft ventricular failure
Bisferiens pulse (double beating pulse)Aortic regurgitation
Bigeminal pulse: two close beats followed by a pause.Premature ventricular complexes
Pulsus tardis & parvis: weak pulse with a delayed systolic peak.Aortic stenosis
Pulsus paradoxus: weak pulse during inspiration, strong during expirationConstrictive pericarditis, tamponade, PE, tension PTX, asthma / COPD, shock, pregnancy, obesity

Postural Tachycardia

  • How To Elicit

  • Measure the heart rate with the patient lying down, and then remeasure it after the patient has been standing for one minute.
  • Interpretation

  • Postural tachycardia is present if there is a rise of >20bpm following standing.
  • Causes of Postural Tachycardia

  • Autonomic dysfunction
  • Low intravascular volume - blood / fluid / electrolyte loss
  • Vasodilation - nitrates, alcohol, fever
  • Cardiac impairment
  • Chronic disease - diabetes mellitus, chronic renal failure, chronic liver disease,
  • Brain tumour - paraneoplastic syndrome
Next Page
Want more info like this?
  • Your electronic clinical medicine handbook
  • Guides to help pass your exams
  • Tools every medical student needs
  • Quick diagrams to have the answers, fast
  • Quizzes to test your knowledge
Sign Up Now

Snapshot: Initialising...