Irregular heartbeat in 5yo on pulse oximeter-

[VforVienetta]

Evening all.
5yo DS2 has regular viral-induced wheeze so we’ve finally got a pulse ox finger thing, so if we’re dithering about the A&E dash we can check his oxygen levels (he rarely dips below 94 on the hospital ones).
I figured it would be a good idea to note the family’s resting rates when we’re all well for a baseline, so did DS1 & DS2’s while they’re asleep.
DS1 was 96/78, heart rate only varying by 1/2 either way.
DS2’s ox was 99 consistently, but his heart rate was all over the place! During two minutes it went like this; 88 83 87 79 84 94 91 86 82 88 92 105 100 104 96 92 90 94 99 111 109 101 105 87 113 109 89 79.
WTF. When i put my ear to his chest the beats sound like B B BBB B BB BBB B B B BBB B BB etc, lots of fast beats together then some normal.
Had a quick Google, and it says;
“In an infant, the heart beats 140 times a minute on average. Some arrhythmias, or irregular heartbeats, are normal. ... This heartbeat variation with breathing is called sinus arrhythmia, and it's no cause for concern. If your child's doctor discovers an arrhythmia, he or she will likely perform tests to learn more.”
DS’s heart has been listened to VERY regularly since he was 7mo as that’s when his breathing difficulties started, but most of the time he’s already ill at that point, so on blue inhaler and sometimes prednisalone (steroids) too, both of which make his heart go crazy.
I’m planning to make a GP appt for DS on Monday, to get this checked out, but does it sound wrong to you?

I am not medical.

Is the sats probe a paediatric one? Normal heart rate for a 5 year old would be 80-120 so it’s in normal range. Listening by ear won’t be accurate. Check YouTube to learn how to take a manual pulse for him. See the gp,if you are concerned.

Yes it's a proper one. Last wheeze episode I asked the GP if it would be useful for us to have one and she thought so.

It's the irregular pulse that concerned me, even tho his readings were all in the normal range, they just didn't stay still!

Doh I misread - no, it's not a specific paediatric one, as this one is apparently suitable for all.
He often has his pulse ox read on a big toe or a thumb as his index fingers don't read well even in the Paeds A&E.
I tried this one on his big toe, thumb, and middle finger, all read the same way.

Nobody can tell you if it's normal or not, but it's not unusual for children to have sinus arrhythmia, which means that their heart rate speeds up when they breathe in and slows down when they breathe out.

Heart rates do change all the time and speeding up and slowing down is different to having an arrhythmia, perhaps he was dreaming? No problem with getting him checked if you're worried though

That's an excellent point VillaMaria, I hadn't thought of that at all. He may well have been having an exciting dream!
I'll check it again tomorrow, when he's doing something very dull indeed...

In the context of a well child that range if pulses is not ‘all over the place’ - it’s fine. Sinus arrhythmia is common in kids (the pulse goes up breathing in and down breathing out). There’s no point in getting ‘baseline’ pulses in kids because the normal range varies so much. Sats probs are pretty useless really - as an anaesthetics/icu doctor my experience is that they’re the least reliable monitor and the one I’d ditch first if I had to make a choice. Other things that may influence the ‘pulse’ include movement/how cold the finger/toe is/blood pressure. If your child looks unwell they need to be seen by a HCP - there are so many other variables than sats that determine how sick a kid is (or adult in fact) having the monitors may be falsely reassuring and frankly dangerous.

Thank you for the advice GreyBeardy it's appreciated.
We're such frequent fliers with DS's viral wheezes that we have a management plan that exceeds the usual guidelines - we manage him at home unless he's having inhalers more than every 2 hours, when it's generally 4 hourly. The A&E team have told us in the past that his pulse ox must be watched when he's unwell,, so normal we head down to the GP to get it checked, but like all kids he seems to get worse overnight or at weekends!

He's absolutely fine at the moment, I was simply freaked out by his pulse rate being so all over the place.