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Deteriorating Patient
Deteriorating Patient

Heart Rate

February 15th, 2021


The heart rate is an invaluable vital sign that is commonly used as part of the assessment of a patient's haemodynamic state.
    • Normal Range

    • 60 - 100bpm
  • How to Measure

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


Heart rate greater than 100 beats per minute.
  • Causes of Tachycardia

  • Sinus Tachycardia

  • Stress - physical exertion, anxiety, emotional stress, trauma, pain
  • Fever
  • Haemodynamic insufficiency - hypovolaemia, shock
  • Anaemia
  • Cardiovascular - pulmonary embolism, coronary ischaemia / infarction
  • Endocrine - hypoglycaemia, thyrotoxicosis, phaeochromocytoma
  • Drugs - beta agonists, anticholinergics, theophylline, caffeine, amphetamine, cocaine, alcohol
  • Other Rhythms

  • Atrial - atrial fibrillation, atrial flutter, focal atrial tachycardia, multifocal atrial tachycardia
  • Junctional - AV nodal reentrant tachycardia, AV reentrant tachycardia
  • Ventricular tachycardia


Heart rate less than 60 beats per minute.
  • Causes of Bradycardia

  • Sinus Bradycardia

  • Sinus node disease - idiopathic degeneration, myocardial infarction, infiltration, connective tissue disease, cardiac surgery, Lyme disease, endocarditis
  • Physiological - high cardiac fitness
  • Autonomic - neurocardiogenic syncope, carotid sinus hypersensitivity
  • Drugs - beta blockers, calcium channel blockers, digoxin, adenosine, ivabradine, clonidine, acetylcholinesterase inhibitors
  • Hypothyroidism
  • Hypothermia
  • Hyperkalaemia
  • Obstructive sleep apnoea
  • Raised intracranial pressure
  • Other Rhythms

  • Sinus node - sinus arrhythmia, sinus arrest, second or third degree sinoatrial exit block
  • Atrial - atrial fibrillation with slow ventricular response, atrial flutter with variable block, trial escape rhythm
  • AV node - second or third degree atrioventricular block, junctional escape rhythm
  • Ventricular escape rhythm

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

  • Reduced intravascular volume - dehydration, haemorrhage
  • Cardiac - congestive cardiac failure, cardiomyopathy, myocarditis, constrictive pericarditis, aortic stenosis
  • Drugs - nitrates, anticholinergics, antidepressants, antihypertensives, levodopa
  • Prolonged bed rest
  • Alcohol
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