Sinus tachycardia

Sinus rhythm with a resting heart rate of >100bpm in adults, or above the normal range in children.

 

• In the vast majority of cases, a sinus tachycardia is a physiological response (via increased sympathetic innervation) e.g. during exercise, stress, infection, blood loss.
  • It is also seen with alcohol and caffeine consumption
• The maximal heart rate for any individual can be calculated as 207-0.7×Age (years). More commonly, this is simplified to 220-Age.
• Pathophysiological causes include
  • Hypoxia, hypercapnia, acidaemia
  • Sepsis, pyrexia
  • PE, heart failure
  • Hyperthyroidism
  • Drugs
    • Beta-agonists e.g. adrenaline, salbutamol, dobutamine
    • Sympathomimetics e.g. amphetamine, cocaine
    • Antimuscarinics e.g. antihistamines, TCAs, atropine
    • Caffeine, theophylline, marijuana
• Patients can present with symtoms of the underlying cause.  Other symptoms may include palpitations, pre-syncope, anxiety etc
• Management is almost always of the underlying cause; If the patient presents acutely (e.g. palpitations, SOB, syncope etc), manage as adult tachycardia (ABCDE) approach (see here)

 

Advertisement