The words โpersistent tachycardiaโ will strike a chill in many of you reading, but there will be those wondering what all the fuss is about. This article is aimed at the latter group, in the hope that you can learn the lessons of both the past and the present to recognise and treat a deteriorating child.
The observation charts below show the pulse rates of an imaginary two-year-old admitted and on ceftriaxone 80mg/kg in Australia and the UK, using the New South Wales (NSW) current โBetween the Flagsโ (BTF) observation chart and a generic UK-based chart.


The most striking feature is that the pulse rate is above the โacceptedโ level for several hours and is what many others and I would define as โpersistent tachycardiaโ (PT) –
โIโll huff and Iโll puffโฆโ
However, as with many things in medicine, you will not necessarily find this written in textbooks or scholarly articles, and no specific definition currently exists. When does it become persistent? 2hrs? 4hrs? Using the charts above, it would be at 1300-1400hrs, but this is an evidence void.
So, whatโs it all about, and why does it matter? Well, this article isnโt about cardiovascular physiology or the mechanism of sepsis. I hope to make you think, really think, about what might be going on.

โIโll blow your house downโ
Whether a child with persistent tachycardia is on antibiotics or not, escalation is required in terms of:
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Senior decision-making and review: Yes, wake your Consultant up, whatever the hour, to make them aware and discuss.
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Bloods – do another gas, where is the lactate heading?
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Antibiotic choice – Do you need to cover gram-negative (gentamicin chaser) or toxic shock syndrome (clindamycin)?
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Further fluid boluses – 10ml/kg vs 20ml/kg dependant on your practiceโฆ
There will be a plethora of cases in many readers’ experiences where the predominant feature of a septic child has been persistent tachycardia. Some will have been acted on, whilst others may have been missed or accepted as โtheyโre just sickโ with potentially devastating consequences. For example, the Clinical Excellence Commission (CEC), NSW, published a document in 2017 highlighting seven root cause analysis investigations (read – significant morbidity or mortality) across the state where the common theme was persistent tachycardia. The Royal Childrenโs Hospital, Melbourne, highlights the importance of persistent tachycardia in their current โfebrile childโ guideline , along with Queensland.
But what about the UK? The National Institute for Health and Care Excellence (NICE) has many guidelines covering sepsis and fever in children, but at the time of writing, persistent tachycardia is not mentioned. Many junior and senior trainees I interact with are new to the concept of persistent tachycardia, and this is probably not isolated to a small hospital in Surrey, UK.
โBut a paediatric early warning system (PEWS), BTF or the NHS-SPOT (System-wide Paediatric Observations Tracking) programme will pick these children up?โ I hear you sayโฆ
Well, yes and no. A PEWS system or variant thereof, which nearly all hospitals now use, should cause an escalation in treatment and/or care. However, this ignores human factors and the complexity of systems within medicine, as noted by Cheung, Roland and Lachman (2018). Many readers will have experienced this blindness or โlearnt acceptanceโ to ignore abnormal observations/PEWS score on a patient with, in some instances, devastating outcomes.
Persistent tachycardia is a phrase I hope becomes part of your own healthcare culture and practice. Itโs one part of a safety culture that should include a PEWS-based system.
Donโt be afraid of the big bad wolf but donโt ignore it eitherโฆ
What do you think? Can we discharge children with persistent tachycardia? Let us know in the comments below












