Implantable and wearable devices Flashcards
what happens if the SA node fails to work
other areas of the conductive tissue will attempt to gain control of the heart creating inconsistent depolarization of the heart, arrhythmias, and decreased CO
How to diagnosis SA node dysfunction
- sinus bradycardia (less then 60 bmp)
- paroxysmal supra ventricular tachycardias (atrial fibrillation, atrial flutter)
what are the 3 types of temporary pacemakers
1) transcutaneous
2) transatrial
3) transvenus
what are temporary pacemakers indicated for
- acute MI
- post cardiac surgery
- drug toxicity
- bridge to permanent pacemaker
what is a permanent pacemaker
- small, lightweight battery operated device
- wires implanted into the heart
- device is implanted into the distal left clavicle area
- sends electrical stimulus directly to the heart muscle
indications for a permanent pacemaker
1) SA node dysfunction
2) 2nd degree AV block with symptomatic bradycardia
3) 3rd degree AV block with symptomatic bradycardia, CHF, atrial fibrillation/flutter, or documented periods of asystole greater then 3 secs or escape rates of less then 40 bpm
4) acute anterior MI with either 2nd degree AV block, 3rd degree AV block or severe bundle branch blocks
conditions that might warrant a pacemaker
1) syncope
2) Dizziness
3) CHF
4) metal confusions
5) palpatations
6) dyspnea
7) exercise intolerance
pacemaker in the atrium purpose
increased the atrial contribution to ventricular filling resulting in an increased CO
pacemaker in the ventrical purpose
increases the ventricular rate in presence of a heart block or symptomatic bradycardia
dual chamber pacemaker purpose
maintains timing between atrial and ventricular contractions, further increasing CO
fixed pacemaker mode of pacing
fires at a specific, preset rate
demand pacemaker mode of pacing
- fired only when the HR is below a present value
- has both a sensing mechanism and a pacing mechanism
rate-responsive pacemaker mode of pacing
- firing depends on pts level of activity and respiration
- automatically increases with increased CO
ICD (implantable Cardioverter Defibrillator) what is it?
- delivers a shock to the heart to cardiovert when a fatal arrhythmia is detected
- quick but painful
what are ICDs indicated for
life threatening arrhythmias
what are the PT implications for pts with pacemakers or ICD
1) know if the pt is dependent on temporary pacemaker
2) be careful with wires - put the box in a pocket and leads around the back of the neck to keep out of the way
Post pacemaker/ ICD implantation precausions
- bedrest for a few hours
- sling on left arm for 24 hrs
- use left UE functionally but avoid overhead movement above 90
- restrict lifting to 5 lbs
- no driving until cleared by electrophysiologists
what is a Holter Monitor?
- an ambulatory electrocardiography device
- a portable device for continuously monitoring the electrical activity of the heart for 24 hours or more
when would a holter monitor be indicated
for someone who it would be difficult to identify cardiac arrhythmias in a shorter time period
what is a VAD (left ventricular assist device)
mechanical pump that takes of the function of the damages ventricle of the heart to restore normal blood flow
purpose of the VAD
allows people with advanced heart failure to be able to return to a better quality of life
what are the 2 types of VAD
1) pulsatile
2) axial flow
what are the indication for VAD
1) bridge to transplant
2) destination therapy
criteria for a VAD implant
- at least 2 admissions to the hospital
- meds not working
- hyponatremic
- hypovolemic
- inotrope dependent
- EF less then 35%
benefits of VAD
- restores CO and BP
- reduces the work of the LV
- improves perfusion to all body organs
”+++”
- blood flow is moving at over 10 L/min through the pump
- might be normal for larger pts
- could be indicative of a clot forming in the pump
”—”
- blood flow is moving at less than 2.5 L/min through the pump
- could be normal for smaller pts
- could be demonstrating that pt is hypovolemic “dry” and requires a fluid bolus
Blood pressure of VAD pts
if pt is pulsatile, manual pressure is preferred (systolic 90-100). pts might be more susceptible to orthrostatic hypotension
MAP in VAD pts
if pt is not pulsatile obtain MAP with manual cuff and doppler (65-85mmHg)
pulse in VAD pts
may be thready or absent
O2 sat in VAD pts
hard to obtain due to poor capillary bed pulsatility
what is impella
- a small device that is deployed endovasculary and helps pump blood from the L. ventrical to the aorta
- temporary
indications for an impella
- HF
- myocarditis
- off pump CABG
contraindications for PT
- VAD malfunction
- intra-aortic balloon pump
- open chest
- active bleeding
- hemodynamic instability
- full ventilator support
PT after VAD placement
- focus on functional
- strict sternal precautions (NO MOVING THE TUBE)
- no percussion or trendenburg
- post op pain might lead to a kyphotic posture and can compromise RR
- post op nausea
- abdominal binder for protection of drive exit site
- EKG might still pick up native heart contractions
- HR blunt by Beta blockers
- CHECK BATTERY LIFE
PT after VAD placement - exercise prescription guidelines
- RPE 11-13
- Stop if symptoms of angina appear, monitor ekg changes, dyspnea greater then 5 , BP drop, O2 sat below parameters
Considerations for mobilization with Impella
1) is the pt on inotropes or vasopressors?
2) mechanical ventilation/ alert?
3) EKG and vitals ok?
4) able to plan movement and not pull lines?
5) is battery life ok?
