Junior Monitor Flashcards
Causes of Overdamping
•Bubble or clot in line or transducer •Small lumen of tubing system •Soft compliant tubing •Loose catheter connection •Kink in catheter Overdamping system is not sensitive enough and yields flat or rounded tracings.
Causes of Underdamping
•System tubing is too stiff •System tubing is too long •Hyperdynamic state •Catheter tip in turbulent jet Underdamping system is too sensitive and produces too much “ringing” or overshoot of tracings.
Select the appropriate uses of the PCWP
- Closely approximates LA pressure
- Overestimates LA pressure in patients with acute respiratory failure, COPD with pulmonary hypertenstion, pulmonary venoconstriction, or LV failure with volume overload.
- Usually sufficient to estimate LV filling pressure
State the appropriate measures taken to obtain an accurate PCWP
•Position the catheter correctly
•Verify correct position by:
Confirming oxygen saturation greater than 95%
Confirm pressure is not a damped PA pressure by confirming A and V waveform timed against EKG or LV pressure.
During fluoroscopy when contrast material is injected the lack of washout 15 seconds after injection indicates proper position. A “fern” pattern of contrast seen of fluoroscopy may help when the hemodynamic tracing is in question.
State the appropriate measures taken to obtain an accurate PCWP
- The system should be thoroughly flushed before accepting wedge pressure.
- Connect the catheter to the manifold with stiff short pressure tubing.
- A stiff large-bore end-hole catheter should be used.
- For mitral valve area determinations the operator should correct for the time delay.
A wave, waveform abnormality, select the appropriate cause: A wave
- Absent, during atrial fib/junctional rhythms
- Elevated during MS, TS
- Elevated during RVH
- Elevated during PS, PHTN
V wave, waveform abnormality, select the appropriate cause:
- Elevated with MR, TR
* Elevated with MS, TS
RVSP, waveform abnormality, select the appropriate cause:
- Elevated in pulmonary stenosis
* Elevated in pulmonary hypertension
RVEDP, waveform abnormality, select the appropriate cause:
Initially in RV failure RV tracings would show a decreased systolic pressure and an increased EDP.
• Elevated in pulmonary hypertension.
PAEDP, waveform abnormality, select the appropriate cause:
•Conditions in which left atrial pressures are increased also increase pulmonary artery pressures.
Pad=mean Paw=mean LA= LVEDP
Given an event occurring during the electrocardiogram, match it to what it represents,
P wave – atrial deploarization
QRS – ventricular depolarization
T wave – rapid phase of ventricular repolarization
ST segment – plateau phase of ventricular repolarization.
Intima (tunica interna)
The inner coat of an arterial wall and is composed of a lining of endothelium and a basement membrane (elastic tissue or internal elastic lumina).
Tunica Media
usually the thickest layer. It consists of elastic fibers and smooth muscle.
Adventitia (tunica externa)
outer layer of the arterial wall. It is composed principally of elastic and collagenous fibers. An external elastic lamina may separate the tunica externa from the tunica media.
Describe the Wheatstone bridge principle,
Pressure signals exerted on a strain gauge converts mechanical pressure signal into an electrical signal.
Arrangement of electrical connections in a strain gauge such that pressure induced changes in resistance result in proportional changes in voltage across the bridge
Explain the findings that occur to pressure tracings on the monitor during coronary artery injections,
During coronary artery injections, the pressure is turned off at the manifold, thus displaying a flat pressure waveform on the hemodynamic monitor.
valvular disease of AS, AI, MS, or MR, list what pressures would be recorded as well as what scale and paper speed would be used to evaluate the severity of such a disease
AS & AI – simultaneous LV and AO pressures are recorded at a 200 mmHg pressure scale 100 cm/sec paper speed.
MS & MR – simultaneous LV and PCW pressures are recorded at a 40 mmHg pressure scale 100 cm/sec paper speed.
Normal pressure waveform: A wave
atrial contraction
Normal pressure waveform: C wave
Closed TV bulging in the RA
Normal pressure waveform: X descent
Downslope of “a” wave caused by atrial relaxation
Normal pressure waveform: V wave
Atrial filling
Normal pressure waveform: Y descent
TV opening and subsequent RV filling
Describe the Left Heart Catheterization protocol and Left and Right Heart hemodynamic Measurements
Left Heart scale-200mmHg
Right Heart scale=40 or 50 mmHg
Right Heart Catheters: Cournand
all-purpose right heart catheter pressure measurements, blood sampling, single end hole
Right Heart Catheters: Lehman
thin wall version of Cournand with a slightly shorter distal curve.
Right Heart Catheters: Goodale Lubin
pressure measurement, blood sampling, 1 end hole and 2 oval side holes.
Right Heart Catheters: Grollman Pigtail
Right Ventriculography and PA angiography
Right Heart Catheters: Bynum Wilson
double lumen PVC catheter with side holes near the distal tip but distal to the balloon. PA angiography and measure PAWP
Angiographic Catheters: Gensini
retrograde L&R heart angiography, 6 oval side holes, within 1.5 cm of 1 end hole, tapered tip
Angiographic Catheters: NIH (National Institutes of Health)
4 or 6 side holes, no end hole, gentle curve RV/LV angiography
Angiographic Catheters: Eppendorf
only the area 20 cm proximal to the hub of the catheter is reinforced with nylon fibers., less stiff than NIH catheter, closed end 6 laterally opposed side holes.
Angiographic Catheters: Lehman Ventriculography
Thin walled, closed-end slightly curved catheter tip tapered to 5 Fr with four sides holes beginning 2.5 cm from tip.
Angiographic Catheters: Pigtail angiographic
with a tapered tip the terminal 5 cm of which is coiled back onto itself in a tight loop. 4-12 non-laterally opposed side holes, commonly used for LV and AO angiography
Angiographic Catheters: Judkins
preformed coronary catheters no side holes one end hole, used for the original is constructed of polyurethane, designed for coronary injections from the femoral with relatively little manipulation
Angiographic Catheters: Sones/Castillo
designed for a brachial approach 80 or 100 cm lengths
Describe the pathway in which blood travels from the heart, throughout the body, and back to the heart
AO, Arteries, Arterioles, Capillaries, Venules, Veins, IVC/SVC, Heart, PA, Lungs, PV
Baroreceptors
Located in the wall of the carotid sinus.
Sends impulses to the vasomotor center to vasodilate and decrease B/P.
Can stimulate vasomotor center to increase B/P and CO if the B/P falls too low.
Can vasoconstrict by increasing sympathetic stimuli.
Chemoreceptors
Sensitive to chemicals.
Carotid/aortic bodies.
Sense levels of Oxygen, Carbon Dioxide and Hydrogen ions.
Stimulated by decreased levels of Oxygen or increased levels of Hydrogen and Carbon Dioxide.
Send impulses to vasomotor center to increase sympathetic tone.
Blood Pressure
pressure exerted on arteries by LV in systole and pressure remaining when ventricle is in diastole
Pulse Pressure
the difference between systolic and diastolic pressure.
Scheme of drainage for right Internal Jugular Vein
is used in an endomyocardial biopsy, drains into the right brachiocephalic vein, to the SVC
Scheme of drainage for right femoral vein
drains into the right external iliac vein into the right common iliac vein, into the IVC
Explain and identify the difference between damping and ventricularization
Damping is a fall in overall catheter tip pressure while a fall in diastolic pressure only is ventricularization
Name the changes that occur to the fetal circulation after birth,
Umbilical arteries vasoconstrict and atrophy to become medial umbilical ligaments.
Umbilical vein vasoconstricts to become round ligament of the liver.
Placenta is afterbirth.
Ductus venosus becomes the ligamentum venosum.
Foramen ovale becomes the fossa ovalis.
Ductus arteriosus closes to become ligamentum arteriosus.
Adverse effects of coronary angiography and its treatment: Bradycardia or Asystole
prophylactic insertion of temporary pacing electrodes is not necessary since most episodes of bradycardia and asystole are brief and are resolved promptly by forceful coughing which elevates central aortic pressure and probably helps wash residual contrast out of the capillary bed.
Adverse effects of coronary angiography and its treatment: Provocation of Myocardial Ischemia
One of the most common adverse effects seen during coronary angiography. Pull catheter back from the coronary ostium and suspend injections until ischemia resolves.
Adverse effects of coronary angiography and its treatment: Marked Arterial Hypertension
if fails to respond to nitroglycerine may administer other vasodilators as needed to bring blood pressure down.
Adverse effects of coronary angiography and its treatment: Allergic reaction to contrast
although uncommon they are best prevented by 18 to 24 hours of premedication (prednisone and cimetidine) and/or the use of non-ionic contrast. If a severe unexpected reaction does occur it usually responds to IV epinephrine. Avoid large bolus doses they may provoke tachycardia, hypertension, and arrhythmia
Adverse effects of coronary angiography and its treatment: Renal Insufficiency
every effort should be made to give adequate hydration both pre and post procedure
A wave
occurs in NSR and follows the P wave; atrial contraction
Peak LV ejection
follows isovolumic contraction on the LV pressure waveform
Isovolumic contraction
follows atrial systole; first component of the LV pressure
C wave
atrioventricular valves bowing(bulging) into the atria during systole
Isovulmic relaxation
follows peak ejection on the LV pressure waveform (Page 588)
V wave=represents atrial filling
The Autonomic Nervous System
regulates vital functions of all organs by both central nervous system and reflex control, but not by conscious control
Sympathetic System
Stimulates the heart by secreting Norepinephrine onto the B1 receptors.
Increases the force of myocardial contraction.
Increases the speed of conduction through the AV node, atria, ventricles and the myocardium.
Stimulates the SA node to pace faster. (Page 57)
Increases irritability of atrial and junctional automaticity foci.
Stimulation of A1 receptors, constrict the arteries through the body increasing blood pressure and blood flow.
Parasympathetic System
Parasympathetic nerves release acetylcholine which activates cardiac cholinergic receptors to produce a cardiac inhibitory effect.
The GI tract is stimulated by its parasympathetic nervous system.
Vagal stimulation = parasympathetic stimulation.
Inhibits SA node, decreasing the heart rate.
Depresses the irritability of automaticity foci, particularly those in the atria and the LV junction. (Page 58)
Diminishes the force of myocardial contraction.
Decreases the speed of conduction, particularly in the AV node.
Stimulation of arterial (cholinergic) receptors dilates arteries reducing blood pressure and flow.
Area of the heart that has suffered a myocardial infarction, select the leads in which this could be seen: Inferior Infarction
ST elevation with/without abnormal Q wave in leads II, III, aVF
Usually associated with RCA occlusion.
Area of the heart that has suffered a myocardial infarction, select the leads in which this could be seen: Lateral Infarction
ST elevation with/without abnormal Q wave in leads I, aVL, V5, V6
May be a component of a multiple site infarction.
Usually associated with obstruction of left circumflex artery.
Area of the heart that has suffered a myocardial infarction, select the leads in which this could be seen: Posterior infarction
Tall R wave and ST depression in V1, V2 and V3 (reciprocal changes).
May be a component of a multiple site infarction.
Usually associated with obstruction of RCA and or left circumflex artery.
Area of the heart that has suffered a myocardial infarction, select the leads in which this could be seen: Anterior Infarction
ST elevation with/without abnormal Q wave in leads V1, V2, V3, V4
Usually associated with occlusion of the left anterior descending branch of the left coronary artery.
The correct method in which a pressure waveform is created
A pressure wave is created by cardiac muscular contraction, and is transmitted along a closed, fluid filled column, to a pressure transducer, converting the mechanical pressure to an electrical signal that is displayed on a video monitor
List indications for a right heart catheterization
Dyspnea
Valvular Heart Disease
Intracardiac Shunts
Select the complications of a right heart catheterization
The most common is the stimulation of the RVOT which results in
Arrhythmias
Advanced AV Block
Rare Right Bundle Branch Block
Significant but transient arrhythmias in 30% - 60% of patients
Select the complications of a right heart catheterization: Access
Major: Pneumothorax, Hemothorax, Tracheal perforation (subclavian route), Sepsis.
Minor: Hematoma, thrombosis, cellulites
Select the complications of a right heart catheterization: Intracardiac
Major: Right ventricular perforation, Heart Block (RBBB), Pulmonary rupture, Pulmonary infarction.
Minor: Ventricular arrhythmias
Name the catheters used during an Aortic Stenosis case
Pigtail Ventriculography Catheter Amplatz Left Amplatz Right Judkins Right Multipurpose Other specially designated catheters
Cardiac Output CO
(AO-MV) x Hgb x 1.36 x 10
Stroke Volume SV
HR
Cardiac Index CI
BSA
Select the appropriate points to remember when crossing the Aortic Valve with guidewires,
Adequate Heparin ( 5000 Units Bolus), frequent catheter flushing
Maximum time of 3 minutes per attempt to cross.
Use 0.038” guidewire instead of 0.035” guidewire for calcific valves.
Manipulate wires gently.
Avoid guidewire configurations leading to the coronary ostia to prevent dissection.
If great difficulty is encountered, a transseptal approach should be considered early.
Select the consequences, if a steady state is not achieved during a Fick Cardiac Output determination,
If steady state is not achieved due to dyspnea, anxiety or elevated O2 level then, Oxygen Consumption will go up and so will the Cardiac Output.
Shallow breathing and oversedation result in a falsely low cardiac output and therefore, a low Cardiac Output measurement.
State the use of the proximal port, distal port, thermistor, and balloon on the Swan Ganz catheter used in Thermodilution Cardiac Output determinations
Proximal – RA pressure measurement, rapid injection of saline for CO.
Distal – Pressure measurement.
Thermistor – measure blood temperature.
Balloon – positioning aid, facilitates PCW measurements.
Select the differences between the Cardiac Output determination techniques
Fick is the best and most accurate during low cardiac output states.
Thermodilution is inaccurate in low CO states, TR or shunts.
Thermodilution is preferred to the Indocyanine green.
Right Atrium Pressures
a-wave = 2-10 mmHg v-wave = 2-10 mmHg mean = 0-8 mmHg
Right Ventricle Pressures
systolic = 15-30 mmHg diastolic = 0-8 mmHg
Pulmonary Artery Pressures
systolic = 15-30 mmHg diastolic = 5-14 mmHg mean = 10-22 mmHg
PCW Pressure
a-wave= 5-15 mmHg v-wave = 5-15 mmHg mean = 4-12 mmHg
Left Ventricle Pressure
systolic = 90-150 mmHg diastolic = 4-12 mmHg
Aortic Pressure
systolic = 90-150 mmHg diastolic = 60-90 mmHg mean = 70-105 mmHg
Systemic Vascular Resistance SVR
1170 +- 270 dynes/sec/cm^-5
Systemic Vascular Resistance Index SVRI
2130 +- 450 dynes/sec/cm-5/M2
Pulmonary Vascular Resistance PVR
67 +- 30 dynes/sec/cm-5
Pulmonary Vascular Resistance Index PVRI
123 +- 54 dynes/sec/cm-5/M2
Describe the procedure of recording left heart pressures
AO / AO mean / AO / LV / LVEDP / LV/ Pullback to AO /AO mean/ AO/ Air zero.
Describe the procedure of recording right heart pressures
PCWP / PCWP mean w/step up to PA Mean / PA / RV / RA / RA mean / RA / Air zero.
