Central Lines Flashcards
How is a central line considered “correctly placed”
when the distal tip of the catheter is at the junction of the superior vena cava and right atrium
what are the 8 indications for central lines
- larger IV access to be able to administer fluids and/or blood at a more rapid rate
- useful in trauma, massive hemorrage - IV access when peripheral IV access fails
- allows us to monitor central venous pressure
- With a central line, we can insert a pulmonary artery catheter (Swan Ganz catheter)
- Allows us to administer certain medications that are contraindicated to administer peripherally
- vasopressors, inotropes - temporary emergency hemodialysis
- can use central line to place temporary trans venous pacing wires
- can use a central line to aspirate an air embolism from the heart
where is the most common central line access site when a peripheral IV cannot be obtained?
external jugular (EJ)
From where does a central line allow us to monitor CVP?
superior vena cava to assess pre-load
what does a high CVP usually indicate?
right heart failure
at what size can an air embolism become fatal in adults?
200-300 mL
3-5 mL/kg
What are 3 indications for long term central lines?
- Chemotherapy
- long term antibiotics (Abx)
- total parenteral nutrition (TPN)
the two types of central lines that stay in for a prolonged periods of time
- PICC line
- “tunneled” lines
- mediport
- broviac
8 complications of central lines
- infection
- venous stenosis
- catheter can lead to inflammation, scarring, and possible eventual occlusion
- can be fatal for dialysis patients - accidental arterial puncture
- thrombosis
- associated with multiple attempts - pneumothorax
- transient arrhythmias during insertion
- caused by seldinger wire irritating the myocardium - nerve injury
- air embolism
are central lines or arterial lines less prone to infection
arterial lines due to higher pressure blood flow
How do you rule out an arterial line puncture when placing a central line?
- the color of blood
2. transducing the blood pressure
carotid artery puncture can be avoided by inserting the needle _____ to the carotid pulse when placing a central line
lateral
2 identifications of a pneumothorax on a chest x-ray
- absence of vascular markings and translucency (looks cloudy)
- trachea and mediastinum can be shifted to the contralateral side
a large bubble in the vein that travels to the heart and causes an obstruction in the pulmonary artery
air embolism
4 signs and symptoms of an air embolism
- sudden decrease in end tidal CO2
- due to decrease in pulmonary blood flow - sudden increase in end tidal nitrogen
- hypotension/ tachycardia
- cyanosis
will PaCO2 be increased or decreased in air embolism
increased
2 risk factors for development of an air embolism
- during central line placement
- during placement, the needle and catheter in the vein provides a path for air entrapment - if the surgical site is above the level of the heart
- open veins above the heart will have a lower blood pressure than veins at or below the level of the heart
- the lower blood pressure in those veins makes it easier for atmospheric air to enter
* *risk increases when the patient is hypovolemic
when the blood pressure inside the veins is low, air entrapment becomes (more/less) likely?
more
2 things a CAA can do to prevent an air embolism while placing a central line
- keep the catheter occluded as much as possible until the line is all hooked up
- place the patient in trendelenburg position
- this position increases venous pressure, engorges the vein, and makes air entrapment less likely
what is the best (most sensitive) way to diagnose/detect an air embolism
TEE
on a precordial doppler, what is the indication of an air embolism?
sporadic roaring sounds
in a “field avoidance” (craniotomy), what is the most appropriate method for confirming a venous air embolism
precordial doppler
-placing a TEE probe in this situation is impractical
6 treatments for an air embolism
- flood the surgical field with saline
- prevents further entrainment of air - Deliver 100% oxygen
- immediately place the patient in left lateral trendelenburg and aspirate the air through a central line port
- give volume to increase CVP
- start a central line and aspirate the air out
- support the patients blood pressure
- vasopressors, inotrope
why do you place the patient in left lateral position for treatment of air embolism?
increases the chances that the air will stay in the apex of the right ventricle
-decreases the chances of the air going into the pulmonary artery
central line access sites with the easiest path to the SVC
- right IJ
- left subclavian
- left IJ
- right subclavian
- right and left EJ
One advantage of the EJ
- most superficial (very easy to cannulate) out of all the central veins
disadvantage of the EJ
- tortuous path to the SVC
- makes it difficult to advance a guidewire or long central line catheters - significant risk of infection due to facial hair and closeness to respiratory secretions
clinical use for the EJ
- the vein is accessed with a REGULAR IV catheter in patients that may be a difficult stick or need a second IV for surgery
What is the EJ mostly used for
Used for regular IV access if the patient is a difficult stick-
-EJ is NOT used a legit “central line” because of the tortuous path to the right atrium
2 advantages of the IJ
- great visualization with ultrasound
- low complication rate (57% less) when using US with IJ placement - the RIGHT IJ provides the easiest catheter pathway to the right atrium
what type of catheter is most easily threaded through the right IJ
pulmonary artery catheter
4 disadvantages to the IJ
- close proximity to the carotid artery
- carries a significant risk of infection (Like the EJ)
- facial hair, secretions - risk of pneumothorax
- uncomfortable to the patient
2 advantages of the subclavian vein
- lowest infection rate
2. least restricting and most comfortable to the patient
clinical use of the subclavian vein
central lines and pulmonary artery catheters are threaded in to the heart much easier if the LEFT subclavian is used
-LEFT side makes a more gradual curve into the right atrium
4 disadvantages of the subclavian
- ultrasound guidance does not provide much benefit
- carries the highest risk of pneumothorax
- bleeding is difficult to control (it is a non compressible vein)
- pinch off phenomenon or pinch off syndrome is possible
what vein carries the highest risk of pneumothorax
subclavian vien
-higher risk in mechanically ventilated patients
how to avoid pneumothorax in ventilated patients
hold ventilation during needle insertion
where the catheter can be compressed between the clavicle and first rib and results in obstruction, tearing, and embolization of the catheter
“pinch off phenomenon” or “pinch off syndrome”
-subclavian vein
how do you recognize pinch off phenomenon or syndrome in the subclavian?
difficult flushing or aspiration with the arm in certain positions
-confirmed with a chest x-ray
the axillary vein (infraclavicular) is considered a _____ approach than subclavian cannulation. Why?
- safer
- ability to visualize the vein with ultrasound
what are 2 advantages to using the axillary vein vs. the subclavian vein?
- lower chance of accidental arterial puncture
- greater distance between artery and veins - lower chance of pneumothorax
- greater distance from the vein to the rib cage
advantage of femoral vein
- easier access sites in an emergency
which vein should only be used in emergency
femoral vein
3 disadvantages to femoral vein
- risk of arterial puncture
- infection
- venous thromboembolism (VTE)
when should a femoral line be replaced?
within the next 24 hours
which vein has the highest risk of infection
femoral vein
which vein has the highest risk for venous thromboembolism?
femoral vein
4 risks unique to femoral vein approach
- femoral artery puncture
- femoral nerve injury
- bladder perforation
- peritoneal perforation
acronym for femoral line central placement
NAVEL (Lateral to medial) Nerve Artery Vein Empty Lymphatics
clinical term that refers to the amount of venous blood returning to the right atrium
venous return
venous return is associated with what pressure?
CVP
when the venous return is decreased, the CVP will be Low/high?
low
4 factors that affect venous return
- volume status
- intrathoracic pressure
- level of vasodilation
- patient positioning
normal venous return
euvolemia
reduced venous return
hypovolemia
3 things that cause high intrathoracic pressure
- positive pressure ventilation
- PEEP
- tension pneumothorax
high intrathoracic pressure (puts/relieves) external pressure on central veins and (increases/decreases) resistance and causes and (increased/decreased) venous return
puts
increases
decreased
what causes negative intrathoracic pressure
inhalation during spontaneous ventilation
negative intrathoracic pressure (puts/relieves) pressure external to the central veins, which (increases/decreases) resistance to blood flow and (increases/decreases) venous return
relieves
decreases
increases
vasodilation causes blood to pool in the legs and (increases/decreases) venous return
decreases
-decreases pre-load
trendelenburg gives a (higher/lower) venous return
higher
reverse trendelenburg gives a (higher/lower) CVP
lower
represents the blood pressure inside a central vein
CVP
what is a normal CVP?
5-12 mmHG
2 benefits to CVP monitoring
- assess patient’s volume status and venous return
- low CVP in a supine position indicates hypovolemia and decreased venous return - assess RIGHT heart function
right heart failure is indicated by a (high/low) CVP
high
3 possible causes to a LOW CVP
- hypovolemia
- reverse trendelenburg or sitting beach chair position
- vasodilation
- increases pooling of blood in legs and decreases pre-load
hypovolemia causes (high/low) CVP
low
what is the treatment for LOW CVP?
volume resuscitation
6 causes for HIGH CVP
- fluid overload
- hard unless pt has renal or heart failure - heart failure (cardiac tamponade)
- pulmonary hypertension
- trendelenburg position
- high intrathoracic pressure
- tricuspid/ pulmonary regurge
2 treatments for HIGH CVP
- restricting intraoperative fluids
2. administering an inotrope (if pt has heart failure) or a diuretic
why does intrathoracic pressure decrease venous return, but increase CVP?
venous return from the head/neck also decreases, starts to pool in the head and central veins, which distends these veins and causes an increase in CVP
“a” wave on CVP waveform
end of diastole
atrial contraction
c wave on CVP waveform
early systole
ventricular contraction
x descent on CVP waveform
mid systole
atrial relaxation during ventricular systole
v wave on CVP waveform
late systole
blood filling in the right atrium (during relaxation)
y descent on CVP waveform
early diastole
opening of tricuspid valve (just prior to atrial contraction)
an abnormally tall wave on a CVP waveform?
on which waves does this occur?
cannon wave
-usually occurs with a and v waves
3 causes of cannon A waves
- tricuspid stenosis
- due to right atrium beating against a partially closed tricuspid valve - complete heart block
- occurs irregularly, when atria and ventricles happen to contract simultaneously - junctional rhythm
- atria contracts late or closer to the time the ventricles contract
when does a cannon wave occur?
when there is an increase in pressure in the right atrium during atrial contraction
cause of a cannon V wave
- tricuspid regurge
when does a cannon V wave occur?
when there is an increase in right atrial pressure during the atrial relaxation period
-x descent is abolished and v wave is elevated when volume from the ventricle back flows into the right atrium during ventricular systole
which waves of CVP are the systole waves?
C, X, V
which waves of CVP are the diastole waves?
Y, A
what makes up a triple lumen central line
one distal and two proximal lumens
what size and color is the distal lumen on the triple lumen central line?
16 G
brown
what is the distal lumen used for in a triple lumen central line?
used for CVP and hooked up to the non-compliant transducer tubing
what size and colors are the 2 proximal lumens in the triple lumen central line?
18 G
white and blue
what lumens in the triple lumen catheter are hooked up to the IV tubing for fluid bolus or infusion lines?
white and blue
what size is the triple lumen catheter
7F
what size is the double lumen central line
7 F
what size and color is the port of the double lumen central line used for CVP?
16 G
brown distal
what size and color is the port of the double lumen central line used for fluids/infusions/
16 G
white proximal
what are the two types of central lines with introducer ports
- 8.5 F percutaneous sheath introducer (PSI)
2. Double Lumen 9F MAC catheter
another name for the PSI introducer port
cordis
what type of central line is required to place pacer wires or a Swan Ganz Catheter
introducer port
advantage of an introducer port
-larger 8.5-9F
disadvantage of an introducer port
have less ports
what additional ports can be added to an introducer port?
- pulmonary artery Swan Ganz Catheter
- gives 3 extra ports: CVP, infusions, pulmonary artery pressure monitoring - companion catheter
- single lumen or double lumen to give infusions or monitor CVP - sinle lumen infusion catheter (SLIC)
- one port that allows CVP monitoring
additional port added to an introducer port that gives 3 extra ports
What are they used for?
Swan Ganz Catheter
-CVP, Infusions, pulmonary artery pressure monitoring
additional port added to an introducer port that gives a single or double lumen
What are they used for?
companion catheter
-give infusions or monitor CVP
additional port added to an introducer port that provides a single lumen
what is it used for?
single lumen infusion catheter (SLIC)
-allows CVP monitoring
how large can a dialysis central line be?
14 F
a dialysis central line is placed as a (short/long) term solution
short
what are the functions of the 2 lumens of a dialysis central line?
one lumen draws blood away to the dialysis machine
the other lumen re-infuses the “purified” blood
a very long catheter that is guided into the superior vena cava through the antecubital vein for long term use
PICC line
how many lumens can a PICC line have?
single, double or triple
PICC lines have (fast/slow) drip rates
slow
long catheter length=more resistance=slower drip rates
tunneled catheter that is sewn under the skin, has a lower infection rate, and requires a needle stick for access
mediport
tunneled catheter that exits the body, has a higher infection rate, and no needle stick is required
broviac
what vein is a mediport placed in
subclavian
tha name of the needle to access the mediport
Huber needle
mediport and broviac catheters require the use of _____ to prevent clotting formation inside the catheter
heparin
how many mL of blood should be aspirated from mediport and broviac catheters prior to dosing fluids/drugs
10 mL
the CAA should flush the mediport and broviac lines with ____ or _____before and after drug administration
LR or NS
