CPT II - Midterm Flashcards
What is automaticity?
Ability of muscle cells to generate their own action potentials
What is rhythmicity?
Action potentials that occur at regular intervals.
What is the function of the intercalated discs in the myocardium?
Gap junctions allow AP to spread and polarize all cells at the same time.
What is a vulnerable period for dysrhythmias in the heart cycle?
During relative refractory period
What does diastole look like on EKG?
Flat line (no electrical activity)
Where is the SA node?
At the base of the superior vena cava (right atrium)
How do you LOOK for cardiac output?
Signs and symptoms
Blood pressure
EKG only shows what kind of heart activity?
Electrical (not mechanical)
When does the SA node fire typically?
When ventricles fill to 80%
What is the AV junction?
Where AV node meets bundle of His (near tricuspid valve)
Dysrhythmias occur as a result from…
altered conduction, rhythmicity, or both
What is an ectopic rhythm?
Rhythm in which the origin is not the SA node
How do dysrhythmias occur?
Hypoxia Ischemia or Irritability Sympathetic stimulation Drugs Electrolyte Disturbances Bradycardias Stretch
How many electrodes are in a 12-lead EKG? What is the purpose of having so many?
10 - each lead has a different view of the heart
What is a bipolar lead?
1 positive and 1 negative electrode
What are the 3 bipolar leads?
Leads I, II, III
What are the 3 unipolar leads?
Leads aVR, aVL, aVF
augmented views - right, left, foot
What is a unipolar lead?
1 positive electrode and 1 reference point
How many views do you need to diagnose a heart condition by EKG?
All 12
Dysrhythmias occur as a result from…
altered conduction, rhythmicity, or both
What is an ectopic rhythm?
Rhythm in which the origin is not the SA node
How do dysrhythmias occur?
Hypoxia Ischemia or Irritability Sympathetic stimulation Drugs Electrolyte Disturbances Bradycardias Stretch
How many electrodes are in a 12-lead EKG? What is the purpose of having so many?
10 - each lead has a different view of the heart
What are the inferior view leads?
II, III, AVF
Limb leads record activity in what plane?
Frontal
Chest leads record activity in what plane?
Horizontal
How many chest leads are there and what are they made up of?
Six unipolar leads made up of a positive electrode and a reference point near the AV node (V1 -> V6)
What is the MCL1 lead commonly used for?
Monitoring. Similar to lead II but now using 5 electrodes instead of 3
Where is the MCL1 positive electrode placed?
Over the 4th intercostal space just to the right of the sternum.
Where is the MCL1 negative electrode placed?
2nd intercostal space midline on the upper left chest or outer third of the left clavicle
What are the anterior view leads?
V1, V2, V3, V4
What are the lateral view leads?
I, AVL, V5, V6
What are the inferior view leads?
II, III, AVF
What is Q-T syndrome?
Prolonged Q-T interval; more danger of repolarization (dysrhythmia)
What is the best method to determine rate via EKG? What is an ok alternative?
Count out beats on full minute of tape
Ok: 6 second strip
What are the 4 places of origin for action potential?
SA node
Atrium
Junction
Ventricles
What is the flat line of diastole also called?
isoelectric line
What is the difference between a segment and an interval?
Segment - straight line
Interval - 1 wave and 1 segment
What is the P-R interval? Normal value?
Beginning of P wave to the beginning of the QRS complex
Normal: < 0.20 ms (5 boxes)
What is the S-T segment? How can it indicate infarction/ischemia?
Plateau phase
Ischemia: > 2 mm elevation or depression from isoelectric line
What is the Q-T interval?
Ventricular depolarization and repolarization
What part of the EKG represents the shift from absolute to relative refractory period?
Q-T interval
What is Q-T syndrome?
Prolonged Q-T interval; more danger of repolarization (dysrhythmia)
Why is sinus tachycardia during exercise not a concern in healthy individuals?
Increased venous return prevents decrease in stroke volume
Time: 1 small square, 1 large square, 5 large squares
1 small = 0.04 s
1 large = 0.2 s
5 large = 1 s
What do you think if you can’t see a P wave on EKG?
Atrial rate is absent OR
Tachycardia is hiding it
When do you use the box method?
For regular rhythm only
What is the best method to determine rate via EKG? What is an ok alternative?
Count out beats on full minute of tape
Ok: 6 minute strip
Normal Sinus Rhythm
Rhythm: regular Rate: 60-100 P waves: normal PR: normal QRS: normal
What is a premature atrial contraction?
For one beat, somewhere in the atria, one site fires faster than the SA node.
Often once or twice per minute.
SInus Tachycardia
Rhythm: regular Rate: 100-150 P waves: normal PR: normal QRS: normal
Sinus tachycardia has the potential to decrease…
stroke volume (less time in diastole)
Why is an accelerated heart rate during exercise not considered sinus tachycardia diagnostically?
Increased venous return prevents decrease in stroke volume
Sinus Arrhythmia
Rhythm: irregular Rate: varies w/ breathing P waves: normal PR: normal QRS: normal
How does the heart rate vary in sinus arrythmia?
Speeds up with inhalation
Slows down with exhalation
Premature atrial contraction
Rhythm: Reg underlying, Irreg at PAC Rate: Normal underlying P waves: Normal underlying PR: normal QRS: normal
How can you see an atrial dysrhythmia
Presence of P wave but it looks abnormal
Every cell in the heart has the ability to be its own pacemaker. SA node is primary because…
it’s fastest
What is a premature atrial contraction?
For one beat, somewhere in the atria, one site fires faster than the SA node.
Often once or twice per minute. Generally benign.
Premature Junctional Contraction
Rhythm: Regular underlying Rate: N underlying P waves: Before/During/After QRS PR: Absent QRS: normal
What does a retrograde depolarization look like?
Inverted wave
Premature Ventricular Contraction
Rhythm: regular underlying
Rate: N underlying
P waves: normal underlying, absent at PVC
PR: normal underlying, absent at PVC
QRS: normal underlying, wide/bizarre at PVC
Atrial Flutter
Rhythm: regular or irregular Rate: Atrial: 250-300 P waves: Flutter (F) waves PR: non-discernable QRS: normal
What is happening during atrial flutter?
Not all atrial depolarizations are getting through to the ventricles - several p waves before every QRS complex
Atrial Fibrillation
Rhythm: Irregular Rate: Uncontrolled > 100 P waves: Fibrillatory PR: Absent QRS: Normal
Unifocal vs. multifocal PVC
Unifocal: origin at one area
Multifocal: more than 1 area of origin
How can you determine a junctional dysrhythmia? Where does the AP originate?
No P wave; AP starts at the QRS complex (AV node)
Junctional Dysrhythmia
Rhythm: regular Rate: 40-60 P waves: absent PR: absent QRS: normal
Premature Junctional Contraction
Rhythm: Regular underlying Rate: 40-60 underlying P waves: Before/During/After QRS PR: Absent QRS: normal
What does a retrograde depolarization look like?
Inverted wave
Premature Ventricular Contraction
Rhythm: regular underlying
Rate: N underlying
P waves: normal underlying, absent at PVC
PR: normal underlying, absent at PVC
QRS: normal underlying, wide/bizarre at PVC
Implication on stroke volume with PVCs?
Lose the atrial kick which may decrease stroke volume (ventricles don’t fill all the way)
What do you do if there are < 6 PVC per min? > 6 per min?
< 6 = treat and monitor
> 6 = don’t aggravate it further, could compromise CO
Signs of aggravation of PVC condition
Amount of PVCs per minute increase
PVCs come from different locations
Unifocal vs. multifocal PVC
Unifocal: origin at one area
Multifocal: more than 1 area of origin
Ventricular Fibrillation
Rhythm: Absent Rate: Absent P waves: absent PR: absent QRS: fibrillatory
What is 3+ PVCs in a row?
Ventricular tachycardia
What is bigeminy?
Every other beat is a PVC
What is trigeminy?
Every third beat is a PVC
Multifocal PVCs look different from each other. What could they signify?
Increased irritation to the ventricles
Ventricular Tachycardia
Rhythm: regular Rate: 100-250 P waves: absent PR: absent QRS: wide and bizarre
What is happening with ventricular tachycardia?
Site is so irritated, it takes over as primary pacemaker.
What is important to know about V-tach?
It is life-threatening!! Patient needs to get shocked out of it.
What is non-sustained ventricular tachycardia?
3+ PVCs in a row but resolves on its own.
Ventricular Fibrillation
Rhythm: Absent Rate: Absent P waves: absent PR: absent QRS: fibrillatory
What is happening during V-Fib
Heart trying to depolarize, but not able to (must de-fibrillate)
What is R-on-T phenomena?
PVC occurs on the T-wave during the relative refractory period. May lead into V-Tach or V-fib
What can an EKG diagnose?
Ischemia/infarction Hypertrophy/heart axis Pericarditis Adverse effects of drugs Dyrhythmias
What is a first degree heart block?
Lengthening of the PR interval (> 0.2 s). Everything else is normal or underlying.
What is a second degree heart block (Wenckebach’s/Mobitz Type I)
Progressive lengthening of the PR interval until it drops a QRS, then it repeats. Usually due to a block within the AV node.
What is a second degree heart block (Wenckebach’s/Mobitz Type II)
Non-conduction of the impulse through the AV node without a prolonged PR interval. Usually due to a block below the AV node.
What is a third degree heart block?
No communication between the atria and the ventricles. Atrial rate and ventricular rate are independent of each other. QRS may be wide.
Atria and ventricles are both firing at their own inherent rate.
What is a bundle branch block?
Delay in conduction through the bundle branches. Widened QRS but regular rhythm.
Hallmark sign of a bundle branch block?
“Bunny ears” in QRS complex.
What is asystole
No rhythm (flat line). Can’t be shocked out of this. Must be seen in more than 3 ways on EKG.
How can you tell a pacemaker rhythm on EKG?
Presence of “pacer-spikes.”
What can an EKG diagnose?
Ischemia/infarction
Hypertrophy/heart axis
EKG paper speed
25 mm/sec
P-wave represents atrial depolarization. How can you tell right from left atrium on EKG?
1st 1/2 is RA
2nd 1/2 is LA
Normal length/amplitude of P-waves
Length: < 0.2 s
Amplitude: < 2.5 mm
QRS represents…
Ventricular depolarization
Normal QRS length
< 0.12 s
What are pathological Q waves?
> 0.04 s and > 1/3 height of QRS complex
T wave represents…
Ventricular repolarization
Infarction is indicated by what kind of T wave?
Tombstone or inverted T wave
What is a U wave
Represents abnormal electrolyte or ion concentrations
PR interval represents…
AV node delay and atrial kick
ST segment > 1-2 mm in deflection is diagnostic for
ischemia and/or MI
QT interval represents…
beginning of ventricular depolarization to end of depolarization.
QT interval can be prolonged by..
drugs, hypothermia, and electrolyte disturbances
If during activity, there is a change in rhythm…
the activity should be stopped and both the rhythm and patient should be re-assessed.
How could you break atrial tachycardia?
Vaga maneuvers (coughing, valsalva)
What is the difference between sinus and atrial tachycardia?
Sinus: rate is 100-150
Atrial: rate is > 150
Patients with A-fib will be on what kind of medication?
Anticoagulants to decrease risk for thrombi
If patient has chronic a-fib, what kind of exercise can they tolerate?
May be able to handle rates > 100 bpm as long as venous return increases with activity
What is a wandering atrial pacemaker?
Primary pacemaker shifts from focus to focus in the atria resulting in irregular rhythm. May lead to a-fib.
Significance of premature junctional contraction?
Monitor, but generally benign.
Significance of premature ventricular contraction?
Signifies irritability of ventricle and need to watch for progression. May signify the predisposition to more lethal dysrhythmias.
Significance of ventricular fibrillation?
No cardiac output!! Needs immediate defib and CPR - no pulse
Significance of idioventricular rhythm
Ventricles are only functioning electrical activity
Is a first degree AV block benign or severe?
Usually benign but should be monitored by MD. No real significance unless accompanied by severe bradycardia.
Significance of Type I 2nd degree block
Depends on symptoms. Will skip a beat but usually asymptomatic. Monitor.
Significance of Type II 2nd degree block?
Depends on symptoms, but can lead to cardiac arrest, no cardiac output.
Signs/symptoms of 3rd degree block?
Decreased cardiac output symptoms
SBAR
Situation
Background
Assessment
Recommendation
Keeping all 4 bed rails up or placing a tray close in front of a patient is considered to be…
restraints
Risk factors for ICU psychosis
Dementia Alzheimer's Substance abuse Age Chronic illness Infection Hypoxia Metabolic disorders Alteration in medication
Critical illness polyneuropathy vs. mypopathy
Polyneuropathy: muscle weakness and sensory loss
Myopathy: steroid-induced myopathy, use of neuromuscular blocks, shutdown of muscular system
Role of PT in acute care
Minimize complications of immobility Maintain strength and flexibility Enhance pulmonary hygiene Early mobility to prevent deterioration OOB to enhance ventilation and perfusion matching Consultant vs. direct intervention
General guidelines for acute care
THOROUGH chart review Know your nurses Know your equipment Standard precautions Inventory Vitals, vitals, vitals Anticipate events Know your limits
What is a Central Venous Catheter?
Catheter inserted in internal jugular vein (IVJ) or subclavian vein (SCV).
It can be used to monitor PAP, CVP, PCWP; put in medications; and take blood samples.
What is PAP?
Pulmonary artery pressure
What is CVP?
Central venous pressure (right atrium)
What is PCWP?
Pulmonary capillary wedge pressure. Represents left atrial pressure via balloon inflation
Problems associated with CVC?
Dysrhythmias
Limit cervical/shoulder ROM
Activity implications of CVC?
Does not contraindicate activity - just be careful around it.
An arterial line is usually placed in what artery?
Radial
Purpose of an arterial line?
Continuous BP monitoring or arterial blood samples for ABG tests.
A-line waveform should be…
nice and regular
How do you protect an A-line? PT contraindications?
Protect: soft splint on wrist in 15 deg ext.
PT: no weight bearing or excessive wrist extension (radial) and no LE mobilization (femoral)
An intracranial pressure monitor is used for what types of patients?
Head injury or surgery patients who are on bed rest.
Normal ICP
0-15 mmHg
4 types of intracranial pressure monitor
Epidural
Subdural/subarachnoid
Intraparenchymal
Intraventricular
What is the equation for cerebral perfusion pressure (CPP)? Normal?
CPP = MABP - ICP
Normal: > 60 mmHg
< 50 mmHg CPP means
decreased perfusion
< 40 mmHg CPP means
completely inadequate perfusion
ICP A-waves look like? Represent?
High spikes
Represent poor prognosis
ICP B-waves look like? Represent?
Erratic
Represent respiratory changes
Lumbar drain is used for…? Precautions?
Used for bedrest, monitoring/draining of CSF
Need HOB flat and spine precautions. Wait for this to come out before PT
An intra-aortic balloon pump (IABP) is for a patient in critical status and assists with cardiac output. Where does it travel? How does it work?
Where: femoral artery into the aorta
Timed with cardiac cycle so that it inflates during diastole and deflates during systole. Aids in propulsion of blood
Complications of hemodialysis
Hypotension
Dysrhythmias
Electrolyte imbalances
Decreased memory
Cardiac effects of inactivity and bed rest
Increased heart rate Increased HR response to activity Decreased VO2 max Decreased CO Decreased blood volume
Hematologic effects of inactivity and bed rest
Decreased blood volume
Increased coagulation
Respiratory effects of inactivity and bed rest
Increased respiratory rate
Risk for PE and atelectasis
Decreased pulmonary function
Poor pulmonary hygiene
GI/urinary effects of inactivity and bed rest
Decreased appetite
Decreased bowel motility and glomerular filtration
Incontinence
Endocrine effects of inactivity and bed rest
Altered hormonal response
Glucose intolerance
Musculoskeletal effects of inactivity and bed rest
Weakness
Loss of motion
Osteoporosis
Neurologic effects of inactivity and bed rest
Sensory and sleep deprivation
Compression neuropathy
Decreased balance
Neurovascular effects of inactivity and bed rest
Orthostatic hypotension
Integumentary effects of inactivity and bed rest
Skin breakdown, pressure ulcers
Psychosocial effects of inactivity and bed rest
Sensory deprivation Depression Boredom Loss of control Emotional liability Irritability
Lung transplantation is indicated for patients with…
irreversible, progressively disabling, end-stage pulmonary disease.
Patients have a life expectancy of less than 24 months. Other therapeutic options have failed.
Ideal timing of lung transplant referral
When patients have less than 50% chance of surviving 2-3 years
Lung transplant is indicated in 4 groups of patients:
Obstructive lung diseases
Cystic fibrosis
Restrictive lung diseases
Pulmonary vascular disease
What type of patient gets the most transplants?
COPD/emphysema
What is alpha-1 antitrypsin deficiency?
Nonsmoking emphysema
Patient can’t have a lung transplant unless they can perform a…
6MWT
Adherence to therapy after transplant is essential or…
organ rejection
If a transplant patient can’t get off of a ventilator…
they will be put on the inactive list until they can get off of it and perform a 6MWT
Transplant survival varies by
Primary lung disease Procedure type (single vs. double) Recipient co-morbidities Recipient age Characteristics of donor lung
Transplant patients must live within…
2 hours of transplant center.
The Lung Allocation Score is calculated using
Waitlist urgency measure calculated using patient characteristics to determine probability of one-year survival if not transplanted
Post-transplant survival measure calculated based upon patient characteristics of surviving transplant for one year
Allocation score is computed by subtracting the two measures and then normalized
What else determines transplant eligibility besides Lung Allocation Score?
Patient’s size and blood type
Why does the LAS work so well?
It is based on severity, not amount of time on the list.
What is the most typical lung transplant procedure?
Bilateral sequential or double lung transplant (BLT)
Where are the incisions for lung transplant?
Thoracotomy for SLT - posterolateral or anterior axillary
Clam shell (bilateral transverse thoracosternotomy) for BLT
What are the 3 main anastomosis during lung transplant?
Bronchus
Pulmonary artery
Pulmonary veins/left atrium
Clinical implications of a thoracotomy?
Very painful - patient may resist taking deep breaths which is bad for pulmonary hygiene
What is the leading cause of mortality post transplant?
Infection.
Patients must wear a mask when they leave a room or house, especially if construction is around (higher risk for fungal infection)
Causes of post-transplant infection
Exposure of allograft to external environment
Blunted cough/pain due to lung denervation
Impaired mucociliary clearance
Narrowing of bronchial anastomosis
Transfer of organisms with donor lung
What is acute antibody-mediated rejection
Occurs within 72 hours of transplant; primary allograft failure with severe hypoxemia.
What is acute cellular rejection
Occur within the 1st year and often clinically unapparent except by transbronchial biopsy.
Symptoms: oxygen requirement, mild SOB, reduction in spirometry, fever, hypoxemia, diffuse pulmonary infiltrates.
Monitored by biopsies at 2-4 weeks post-op, then at 3 month intervals
What is bronciolitis obliterates?
Cause of death for most transplant recipients surviving > 1 year
What immunosuppressive drugs are used post-transplant. Why are they hard on the body?
Calcineurin inhibitors (cyclosporine)
Antiproliferative agents
Steroids
Transplants need a higher dosage of these drugs due to constant exposure
Role of PT post-transplant
Assess functional ability Assess exercise tolerance (6MWT) Supplemental oxygen needs Musculoskeletal assessment Optimize pulmonary hygiene/airway clearance Outpatient pulmonary rehab
Inotropes are…
medication support for heart failure
Examples of surgical management for heart failure
CABG, stents, heart transplant
Indications for cardiac transplant
End-stage cardiac disease
What is a Status 1A in the UNOS system?
Sickest patients who need continuous inotropic support. They require invasive monitoring and could die within weeks. Receive ventricular assistive device support.
What is a status 1B in the UNOS system?
Need inotropic support but don’t need to be in the ICU. Life expectancy is less than 1 month.
What is status 7 in the UNOS system?
Patient was listed but then removed for the time being (stopped going to appointments, used drugs, cancer work-up)
It is very rare to get a transplant unless you are classified as what status?
1A or 1B
Acute heart rejection presents as…
low grade fever, fatigue, decreased exercise tolerance, and hemodynamic instability depending upon severity
How does a heart transplant infection appear?
Fatigue, abdominal discomfort, fever
PT interventions for heart transplant
Aerobic training
Monitoring exercise tolerance
Strength training (60-70%)
Sternal precautions for heart transplant
Weight restriction of 5-10 lbs
No shoulder elevation > 90 deg
No horizontal abduction
No driving 6-8 weeks
Heart transplant is denervated. Implications for workout?
Heart relies on catecholamines to increase heart rate which takes a lot longer. Patient needs at least a 10-15 minute warm-up and cool down.
Can’t stop abruptly - venous return can cause dysrhythmias.
What is a VAD used for
Patients with heart failure but lower on the transplant list.
What are the 4 types of VAD utilization?
Bridge to Transplant (BTT) - used to help them last until receive transplant
Bridge to Recovery (BTR) - used for temporary support when healing from viral cardiomyopathy, myocarditis, etc.
Bridge to Decision/Candidacy
Destination Therapy
Why is it important to assess the right side of the heart when looking to put in an LVAD?
Device assists the left side only. Right side needs to work in order to pass blood to the left side.
Evolution of LVAD devices
Pulsatile –> Axial flow –> centrifugal
What is the Heartmate II?
Axial flow left VAD; designed to be smaller and more reliable than pulsatile pumps. Designed to spin and deliver as much as 10 L/min of CO.
Clinical issue with the Heartmate II?
Blood flow is continuous, so no longer able to assess blood pressure or pulses.
If a person has an LVAD and they are found to have ventricular tachycardia, what do you know about this patient?
The right atrium is not working.
What is the Heartware HVAD pump?
Centrifugal pump sewn into the apex of the left ventricle. More reliable and less signs of infection since patient does not need a pump pocket.
What is the Thoratec VAD?
Pneumatic device used for partial or total circulatory support. Capacity for flow output is up to 7.2 L/min. Usually used in BTR because it’s easier to remove.
Blood is ejected from sac using compressed air. There is a risk of kinking the cannula and it’s very loud/cumbersome. But it has a backup hand pump for emergencies.
Requires blood thinners.
What should you know about performing CPR on a patient with a VAD?
HVAD is the only device you can do chest compressions on, since it’s sewn into the heart.
Otherwise, you need to decannulate the patient first.
Aerobic exercise considerations for VAD patient
Use larger muscle groups
Promote increasing duration
Running/jumping is bad
Swimming is bad
Flexibility/strengthening considerations for VAD?
Limits in forward bending and trunk rotation due to pump in abdominal wall
Include active shoulder forward elevation
Promote exercise using patient’s body weight, such as modified squats or progressive step heights.
Terminating exercise with VAD
Subjective intolerance
Loss of “flash” with the thoratec VAD
LVAD flows below 3 L/min
Etiology: hypovolemia, vasodilation, arrhythmia
What is the Cardiowest Total Artificial Heart?
Air driven pulsatile pump providing total support. Used for biventricular failure. It has the highest BTT success rate.
