Pacemaker Malfunctions

Even less amusing!

Pacemaker Codes (NASPE/BPEG)

Position I II III

Category Chamber(s) Chamber(s) Response to

paced sensed sensing

O=None O=None O=None

A=Atrium A=Atrium T=triggered

V=Ventricle V=Ventricle I=Inhibited

D=Dual (A+V) D=Dual(A+V) D=Dual (T+I)

Triggered

Means different things If an intrinsic event is sensed, the

pacemaker will trigger pacing to that chamber OR to another chamber

– P wave will trigger an AV interval– R wave will trigger pacing to the ventricle

Triggered?

Atrial paced spiketriggers AV interval

Triggered ventricular pacing spike is in refractory period of ventricular cycle

A O O

Chamber Paced

Chamber Sensed

Action or Response to a Sensed Event

AOO Pacing

Asynchronous mode

Not sensing so can’t react

V V I

Chamber Paced

Chamber Sensed

Action or Response to a Sensed Event

VVI Pacing

Even more!

Fourth letter-Programmable Functions R = rate modulation C = Communicating M = Multiprogrammable S = simple

programmable O = None

Fifth letter – antitachycardic functions O = none P = paced S = shock

Rate Modulation

Atrium or Ventricle is pacing or tracking above the set upper limit (permanent pacemaker) Used to help compensate for increased

demands– Sensor can be:

Change in temperature Change in movement or body position Change in pH Change in minute ventilation

D D D R

Chamber Paced

Chamber Sensed

Response to a Sensed Event

DDDR Pacing

Rate modulated

Pacing Malfunctions

Often a two person job One person supports the patient One person troubleshoots the pacemaker

Failure to pace (not tryin’ to tickle)

No pacing spikes or not enough coupled with the intrinsic rhythm to ensure good CO

Pacing energy not being transmitted from generator to patient

Failure to pace ( not trying to tickle)

How do you fix this?

Pacing spikes not visible (often an equipment problem) Pacer on? Rate set correctly? Battery fresh ? Connections tight? Get another cable Get another generator Often an equipment problem-no energy thrown

Failure to capture (target is not ticklish/not ticklin’ hard enough)

Pacing Arm is throwing out energy-target is not responding

Loss of Capture (target is not ticklish)

Nothing happens in response toarm throwing out impulse

How do you fix this?

Myocardium is not responding to stimulation Battery fresh? Connections tight?

– Make sure lead is in contact with myocardium mA high enough? Assess electrolytes, oxygenation, acid base

balance Ischemic tissue? Fibrin sleeve? Reposition patient or patient’s arm on side of

pacemaker if subclavian entry

Undersensing (ticklin’ too much)

Intrinsic rhythm not seen so pacing arm throws out energy

Undersensing (ticklin’ at the wrong time)

Pacer eyeball is set too high!Can’t see target moving so the armthrows out a stimulus

The danger of “not seeing”...

Pacer arm throws outstimulus during vulnerableportion of cardiac cycle

How do you fix this

Pacermaker not seeing correctly Battery fresh Connections tight

– Leads in contact with myocardium– Lead fracture

Do a sensitivity threshold to get eyes at proper level

Oversensing ( not ticklin’ enough)

Pacemaker misinterprets noncardiac events as intrinsic activity

Oversensing (not ticklin’ enough)

Pacer eyeball thinks it seescardiac activity so the arm doesnot throw out an stimulus

How do you fix this

Pacermaker not seeing correctly Battery fresh Connections tight

– Leads in contact with myocardium– Lead fracture

Do a sensitivity threshold to get eyes at proper level

Let’s practice

Other Complications

Infection Pulmonary

embolus Venous Thrombus Myocardial

perforation Endocarditis

Nursing Care

Assess heart rate and rhythm

Protect patient from injury

Troubleshoot malfunctions

Evaluate pacemaker function

Keep patient informed

Sample documentation

Temporary pacemaker (0800) Epicardial wires ( 2 ventricular) Pacing threshold 3; mA set at 6 Sensitivity threshold 4 mV; mV set at 2 mV Rate set at 60; patient’s intrinsic rate 30 Patient pacing about 50% of time. 100% capture

when paced. Temporary pacemaker (1400)

Pacemaker off. Pacing wires grounded and taped to chest wall. Site care with betadine.

Flippin’ a switch

What’s the deal with the magnet?

No Magnet

With Magnet

Rapid Atrial Pacing

Rapid Atrial Pacing

Used only in the atrium Pace at rates from 80-800

Need to get higher than patient’s ATRIAL rate

Physician must be present when in use Nurse may only connect

Always have defibrillator available

What are the possibilities?

Single chamber pacemaker Dual chamber pacemaker Free standing RAP machine

Think Frankenstein

Rapid Atrial Pacing (single chamber)

Flip open top of pacemaker Press enable to begin

Set rate according to physician instruction or let MD set rate Rate will be higher than

patient’s atrial rate Press hold to deliver

until instructed to stop Will be done in bursts Pacing light will flash

Rapid Atrial Pacing (dual chamber)

Found on bottom half of pacer

Must hit menu screen and scroll to menu 3

Set rate by turning round knob

Press select to deliver and HOLD until instructed to release Menu

Select

3

DDD

80 440 800

RAP 320

SELECTPress

to Deliver

Rapid AtrialPacing

Permanent pacemakers

Differences

You cannot access pacing generator You cannot see leads Helps interpretation of strip if you know

how pacemaker is set up Should have card Old records Request info from cardiologist

You are in trouble!

What can you try if you have a malfunction with a permanent pacemaker that is compromising your patient?

Biventricular pacemakers?

Pacing leads in the RV and into the coronary sinus

Allow both ventricles to pace synchronously

Improves heart function for patients with CHF

EKG will not look different from single ventricular pacing

The END