onetreehill

[onetreehill]

Please can someone explain why a patient with a pacemaker kept her paced rhythm of 70 bpm with a fever 39.3 to 40 degrees C?   I thought pacemakers could vary the rate to meet metabolic requirements.  Thank you.  Ruth

[grendslori]

Thank you for your comment about my daughter. Unfortunately, this is not the case anymore. She is in chronic heart failure with a transplanted heart. She has an extremely rare form of Glycogen Storage Disease known as PRKAG2. Take care and good luck with your project.

[onetreehill]

Do hope your daughter is lots better now.   I appreciate the information you gave, and will follow it up with a pacemaker clinic to get more detail.  What you said makes sense.

To ed34:  pulse rate increases naturally in response to a high fever to supply more O2 and nutrients to vital body parts, e.g., the heart, brain, lungs, kidneys.  That's how our bodies function.   Failure to do so puts more strain on these organs, and shock can potentially set in.   At 41 deg. C., brain cells  start dying off.   40 degrees for elderly people is dangerous as they lack the physical reserves to cope for any extended time. High fever burns up their glucose stores (calories),  then they start burning up their muscles for energy to stay alive.  I'm not a doctor either, but trying to understand the implications a fixed pulse rate had for this person.   Luckily we were able to get her to proper medical help, so she survived, but I need to explain the technical bits, so will try the expert panel and see what they say.   Thanks for your interest and the dialogue.  

[ed34]

Many pacemakers these days have a form of variable rate. Some are based on body movement and others on respiration rate. I don't think a person would have trouble handling 40 degrees for a few days either, you would just have to ensure dehydration doesn't occur. I have no idea about the effects of a fixed heart rate of 70, but logically thinking about it, the main concern would be controlling blood pressure. Of course, if the heart needs to run faster, they could raise the lower threshold in the pacemaker.

[grendslori]

Sorry Ruth I can not help you there as I am not a doctor, nor is any one as far as I am aware on this forum. You might want to check with the EXPERT Forum as a doctor will answer your question. I worked as a tech in the cardiology field and one of the heart issues my daughter had was Sick Sinus Syndrome.

[onetreehill]

Thanks for the feedback.   Needed for a case study I'm preparing.
To return to this patient, what would be the metabolic implications here?   Nothing happened because she was transferred quickly, but would she have gone into metabolic acidosis?  Or respiratory?  Am unsure of the mechanism of these actions.  Many thanks.  Ruth.

[grendslori]

Hello. Usually the heart rate would increase when a fever is present. If a patient has Sick Sinus Syndrome where the heart rate cannot increase  because the sinus node is "sick" then a pacemaker is implanted and a range of, usually, 60-100 beats per minute is set. If this person's heart rate cannot increase ON IT'S OWN and their pacemaker is set at a low rate of 70 beats per minute, the fever will not cause the heart rate to go up because it can't. Pacemakers are designed primarily to keep the heart rate from falling into a dangerous level, if the person's heart rate is an acceptable rate for the exercise the person is doing, the pacer may not fire off at all because the body's needs are being met.