Aai, Vvi, Ddd??????

AfloydRN, BSN, RN · Oct 11, 2006

Ok- Pacer questions- First is chamber sensed, chamber paced and third is what the pacer is going to do w/ the information it receives.So, that said- VVI means sensing ventricular, pacing ventricles and ignoring any info other than what the ventricle is doing. So, DDD means that it is Dually( atria and ventricle) sensing and pacing and is demand pacing. AAi- atrial sensing and pacing- ignoring everything else. Does this help at all? It can be confusing at first but once you learn it you will remember.

SEOBowhntr · Oct 22, 2006

Hi Since I am new to Cardiac Ward I sometimes look after patients that are still connected to pacing. However, I am not competent in understanding what VVI, DDD, AAI means. When I do handover I need to mention this. This is where I would like to understand what why when questions. Also what does it mean Atrial Output sensitivity and Ventricular output sensitivty measure millivolts?
I think I shouldnt be looking after these patients until I am competent and that wont be until next year. However it doesnt hurt to get a step right up and find out earlier so that when I am giving handover I am understanding what is going on with this patients heart.
Look forward to your help.

???

Output is measured in milliAmps or MA, Sensitivity in milliVolts or MV, When dealing with temporary pacemakers, a lack of understanding of these things fortunately is only unsafe if the patient desperately needs the pacer, you really can't kill anyone with a pacer, however you can adversely affect their recovery pathway. There is a great deal to learn, and this learning curve can be very harsh when dealing with patients who are in need of pacing and you are unable to satisfy that need. Each of the nurses in my unit is REQUIRED to pass a Pacing Competency yearly, in order to complete RN Specific competencies on my unit or Critical Care.

**canoehead, BSN, RN** · Oct 22, 2006

Hey thanks, I was confused by that too.

SEOBowhntr · Oct 22, 2006

I guess expanding on this, the sensitivity is an "INVERSE" relationship, lower mV is actually more sensitive, most temporary pacers I've seen have full sensitivity around .4mV for the Atria, and .8mV for the Ventricle. The higher the mV, the less sensitive the pacer is. Most of the time you won't have to mess with the Sensitivity, you can usually put the pacer on Full Sensitivity, and not have problems, if you start having oversensing at full sensitivity, then you can decrease the sensitivity by INCREASING the mV, to prevent that from being a problem. With temporary pacers, because the wires are far less durable than a permanent pacer, I teach my nurses to obtain 100% Capture or the Pacing Threshold, then set the pacer 2mA above the "Pacing Threshold." Again, there is a great deal to learn to being able to use these pacers to do a variety of things to optimize output, but probably the most important thing to remember is that you cannot really harm the patient with the pacer.

augigi, CNS · Nov 1, 2006

I'd say pacing is too complex to explain here. All you need to know for handover at this stage is:

1. What is being paced? Atria, ventricles or both?

2. What is the rate set at?

3. Is it currently pacing or just set as a backup?