I was asked a question that I thought I'd post here.
"Can you tell me what a foetal heartrate of over 190bpm with little to no variation means?
No-one at the time told me exactly what this means, and so I wonder was the C/S really necessary and would everything have been ok if I had birthed vaginally."
That kind of depends on what else was going on. This is one of those more hazzy areas in fhr interrpretation. I'm going to quote to you mostly from monitoring textbook so you can see what is being taught.
The most common cause of an increased heart rate is a fever in mom, not necessarily a problem with the baby. It is also caused by some medications or dehydration. It is not believed to be an indication of the babies status as long as there are no decelerations(decreases in the babies heart rate).
It does tax the babies oxygen reserves though, so I could see a doctor wanting to do a c-section do avoid this. It is also seen after a baby has been having some problems.
If there is no variability along with it, it is hard to determine if it is due to complications or not. It could be more serious if it has the decelerations I talked about or has no variability.
Minimal variability is seen during sleep cycles, or from some medication use. Sleep cycles can last up to 75 min.
Tracings that show minimal or absent variability may also be due to other underlining neurological problems with the baby.
It is also common to see minimal variability with tachycarida. The best indicator that a baby is not doing well(though it is still not very good), is when there is absent variability with decelerations or bradycardia(low heart rate <110).
In your case I would hope that other measures where taken to make sure the baby was healthy. This would include decreasing your temperature if you had one, make sure you were hydrated, and looking over your medication history. I would also look at the previous heart rate tracings for what is called accelerations(an increase in the heart rate for a breif time). This is a great indicator that the baby is doing well. I would also make sure you were feeling the baby move. Waiting for awhile to make sure that the baby is not just sleeping would also be good. You could drink juices or something sugary to wake them up a bit.
Basically this is a hard judgement call by the doctor. Some would be more tolerant of the this situation than others. But tachycardia and minimal variability are not an indication in of themselves for a c-section. They are in the maybe section, which, quite honestly, many fetal heart rate tracings are.
Fetal Heart Monitoring Principles and Practices. Published by AWHONN as a part of the Fetal Heart Rate Monitoring Program.