MS SL Vascular Access Devices

What is the main purpose of a vascular access device (VAD)?

Direct access to the bloodstream: for medications, fluids, nutrition, blood products, blood sampling, hemodialysis, and blood pressure monitoring.

What are the two broad categories of VADs, and how are central VADs further divided by duration?

Peripheral and central. Central VADs are short-term (days to weeks, e.g. non-tunneled catheters, PICC) or long-term (weeks to months, e.g. tunneled catheters, implanted ports).

Compare peripheral and central VADs on skill level, vein size, blood mixing volume, and complications.

Peripheral: basic skill, small vein, low mixing volume, minor complications.

Central: advanced skill, larger vein, high mixing volume, major complications.

What are the two minor complications typical of peripheral IV lines?

Phlebitis (inflammation of the vein: redness, warmth, pain) and infiltration (fluid leaking into surrounding tissue).

Why do central lines allow better drug distribution and dilution than peripheral lines?

They terminate at the vena cava where blood flow is high, giving rapid dilution. The larger diameter also protects the vessel lining from irritation by caustic or high-pH medications.

What are the two major complication categories specific to central lines?

CLABSI (central line-associated bloodstream infection) and complications from insertion near the great vessels, such as embolism, pneumothorax, and DVT.

Which central line insertion site has high visibility and ease of access, with a LOWER risk of pneumothorax?

The internal jugular vein.

Which central line insertion site is more comfortable but carries a HIGHER risk of pneumothorax, and why?

The subclavian vein, because it runs over the apex of the lung.

Which central line insertion site is preferred in emergencies, and what's its major drawback?

The femoral vein, chosen for its larger diameter and lower risk of collapse. Its drawback is the highest risk of infection (femoral tract infection).

Why does a PICC line carry no risk of pneumothorax?

It's inserted in the arm, distant from the lungs.

Where does the tip of a properly placed central line terminate?

The superior vena cava (SVC).

Why is the SVC the ideal location for a central line tip?

It has the highest blood flow back to the heart (preventing thrombosis and allowing rapid hemodilution), gives accurate hemodynamic monitoring, and has no valve impeding flow into the right atrium.

How is a non-tunneled percutaneous catheter inserted, and how long can it stay in?

By direct bedside puncture into the vein, without passing through subcutaneous tissue. Used for a few days to a few weeks; can have multiple lumens.

What insertion sites and technique are used for a non-tunneled percutaneous catheter?

Subclavian, internal/external jugular, or femoral vein, done at bedside via direct puncture, held with sutures or securement devices.

Why does a PICC line carry a lower infection risk than an IJ or femoral catheter?

Lower bacterial density on the arm compared to the neck or groin.

Where is a PICC line inserted, and where does it end up?

In the antecubital fossa or upper arm (basilic or cephalic vein), advanced until the tip reaches the superior vena cava.

What is the major complication of a PICC line, and what's a contraindication to placing one?

Upper-body DVT, since it can damage smaller peripheral veins. Contraindicated if the patient will undergo hemodialysis.

What makes a tunneled catheter last longer than a non-tunneled one?

It passes through subcutaneous tissue before entering the central vein, giving a better anchor and making it harder for bacteria to reach the vein through the skin.

What holds a tunneled catheter in place, and how long does that take to form?

A Dacron cuff coated in antimicrobial solution. Scar tissue forms around it in about 2 to 3 weeks, fixing the catheter in place.

Name the three classic tunneled external catheters.

Hickman, Broviac, and Groshong.

How does the Hickman differ from the Broviac catheter?

The Hickman is a larger version of the Broviac. Both are flushed with heparinized saline, but the Broviac is typically used for pediatric clients.

What makes the Groshong catheter unique?

A 3-way valve stays closed when the line is not in use, so blood doesn't move up the line, meaning it only needs normal saline (not heparin) to flush.

How is an implanted venous port (port-a-cath) accessed, and how often is it flushed?

Through a septum using a noncoring (Huber) needle. Flushed every 4 weeks with heparin to prevent clotting.

What is a dual-port implanted device used for?

Running two therapies at once, for example one port for chemotherapy and another for parenteral nutrition (as in GI obstruction from colon cancer). Can also be used for blood transfusions.

How is placement of a central line confirmed after insertion?

Chest x-ray (CXR).

What are the three major complications tied to a central line's proximity to the great vessels?

Air embolism, pneumothorax, and deep vein thrombosis (DVT).

How much air can cause signs and symptoms of an air embolism?

As little as 10 cc.

What position should a patient be placed in if air embolism is suspected during CVAD removal?

Left lateral (side-lying), since air tends to get trapped in the right side of the heart.

What is the most definitive test to confirm a CVAD-related bloodstream infection (CLABSI)?

Blood culture and sensitivity (C&S).

What are the classic local signs of CVAD site infection?

Rubor (redness), dolor (pain), tumor (swelling), calor (heat), and pallor.

What's the priority management for a confirmed CLABSI?

Remove the CVAD immediately, with a doctor's order, to prevent further bloodstream infection, and obtain a culture and sensitivity.

What signs/symptoms suggest CVAD occlusion?

Dyspnea, pain, and solutions that won't infuse even on a fast drip.

If a CVAD is occluded by a clot, should the nurse flush or aspirate first?

Aspirate first, never flush directly. Flushing risks pushing the thrombus into circulation, causing embolism (heart attack or stroke).

What is catheter malposition, and what's the danger?

The catheter tip fails to reach the SVC. Drugs may be redirected to the wrong location, even the brain, so reinsertion is required.

What should a nurse do if a CVAD becomes dislodged?

Stop all infusions, and avoid pushing the catheter back in, since that could introduce bacteria into the bloodstream.

What complication can occur if a catheter migrates and ends in the myocardium instead of the vena cava?

Dysrhythmia.

What signs suggest a pneumothorax occurred during or after CVAD insertion?

Absent or diminished breath sounds, desaturation, and restlessness. Confirmed by chest x-ray.

What's the difference between hemothorax and hydrothorax?

Hemothorax is blood in the pleural space; hydrothorax is serous fluid in the pleural space

What's the immediate treatment for a pneumothorax, hemothorax, or hydrothorax from CVAD insertion?

Chest tube insertion, which requires consent.

How often should a CVAD gauze dressing be changed, versus a transparent (Tegaderm) dressing?

Gauze: every 48 hours. Tegaderm: only when soiled.

Why measure arm circumference in a patient with a PICC or central line in the arm?

To detect swelling from fluid leaking into the surrounding tissue (infiltration).

What is the most feasible artery for an arterial line, and how is patency checked before insertion?

The radial artery. Patency is checked with Allen's test.

What color is arterial blood, and can arterial lines be used to give medications?

Bright red. Arterial lines are for monitoring and ABG sampling only, never for medications or IV infusions.

What are the indications for placing an arterial line?

Hemodynamic instability, vasoactive drug use (e.g. norepinephrine, epinephrine, vasopressin), the need for frequent ABGs, and arrhythmia monitoring.

To what pressure is an arterial line's pressure bag inflated, and why?

300 mmHg, because arterial pressure is high since blood comes directly from the heart's pumping action.

What does the continuous 1 to 3 mL/hr normal saline flush through the pressure bag do?

Keeps the line patent and prevents backflow or clotting at the catheter tip

Why must arterial line tubing be non-compressible?

So the transducer reads pressure directly from the patient, with zero compliance, rather than a distorted reading from compressible tubing.

What does the transducer cable do in arterial line monitoring?

Interprets the patient's blood pressure and transmits it as a waveform to the cardiac monitor.

What is the VAMP system, and what does it help prevent?

A closed, needleless Venous Arterial blood Management Protection system for prickless blood draws and flushing. It avoids drawing diluted blood and reduces iatrogenic anemia and infection risk.

How often should the heparinized flush solution on an arterial line be changed?

Every 3 to 4 days, for infection control.

What stopcock position is used during normal arterial-line monitoring, and when is it closed to the patient?

Open to both patient and transducer. Closed to the patient only during zeroing or blood collection.

Where should an arterial line transducer be leveled, and what happens if it's positioned too high?

At the phlebostatic axis (4th intercostal space, mid-axillary line). Too high gives a falsely LOW pressure reading.

When drawing an ABG from an arterial line, why use two syringes?

The first sample is discarded because it's diluted with saline. The second syringe is the actual sample used for ABG analysis.

What are the 5 Ps of neurovascular assessment?

Pain, Pallor, Paresthesia, Pulselessness, and Paralysis.

What does the dicrotic notch on an arterial waveform represent?

Closure of the aortic valve, causing a brief, slight increase in pressure.

What is pulse pressure, and what is its normal range?

Systolic minus diastolic pressure. Normal range is 30 to 50 mmHg.

What does a pulse pressure below 30 suggest, versus one above 50?

Below 30: heart failure or low blood volume. Above 50: rigid arteries, as in atherosclerosis.

What is the formula for Mean Arterial Pressure (MAP), and its normal range?

MAP = [Systolic + (2 x Diastolic)] / 3. Normal range is 70 to 100 mmHg.

What does a persistently LOW MAP suggest, and how might it be treated?

Decreased perfusion, often treated with inotropes

What does a persistently LOW MAP suggest, and how might it be treated?

Decreased perfusion, often treated with inotropes.

What are the signs of an OVERDAMPED arterial waveform?

False LOW systolic BP, absence of a dicrotic notch, a flat or rounded top, and systolic decreasing while diastolic increases (MAP unaffected).

What causes an overdamped waveform, and how is each fixed?

Kinked cannula (unkink), loose connection (secure and tighten), occlusion (replace tubing or aspirate the clot, don't flush), or cannula pressing against the arterial wall (reposition or change dressing).

What are the signs of an UNDERDAMPED arterial waveform?

False elevated systolic BP and falsely low diastolic, a spiking dicrotic notch, a sharp spiking peak, and a large above-normal waveform (MAP unaffected).

How is an underdamped waveform fixed?

Replace a defective, overly long, or overly stiff arterial line tubing.

What is the Square Wave Test used for, and how is it performed?

To check that the transducer and tubing system are working. Flush saline directly into the transducer, then watch for oscillations after the square wave.

How do you interpret the Square Wave Test: no oscillations versus more than 2 oscillations?

No oscillations means overdamped. More than 2 oscillations means underdamped.

Does the Square Wave Test diagnose the underlying clinical problem?

No, it only confirms whether the transducer and reading mechanism are working. The underlying cause still needs to be troubleshot.

What is a Swan-Ganz (pulmonary artery) catheter, and where does it end up?

A catheter inserted via a central vein that travels through the right heart and lodges in the pulmonary artery.

What does the thermistor tip of a Swan-Ganz catheter measure?

Cardiac output and temperature.

What does the PA distal port of a Swan-Ganz catheter measure?

Pulmonary artery pressure and pulmonary (capillary) wedge pressure (PCWP).

What does the proximal port of a Swan-Ganz catheter measure?

Right atrial pressure and CVP.

What confirms that a Swan-Ganz catheter has reached the pulmonary artery?

Presence of a dicrotic notch in the waveform, similar to an arterial line waveform.

What are the normal pressures for the right atrium and for pulmonary artery (capillary) wedge pressure (PCWP)?

Right atrium: up to 6 mmHg. PCWP: up to 12 mmHg, an indirect measure of left atrial pressure.

What does an elevated PCWP suggest?

Cor pulmonale.

What is the relationship between blood volume, CVP, and stroke volume?

Directly proportional: increased blood volume raises both CVP and stroke volume, and vice versa.

Define stroke volume and cardiac output.

Stroke volume: the amount of blood pumped per contraction. Cardiac output: the amount of blood pumped by the heart per minute.

What's the difference between a manometer system and a transducer system for CVP monitoring?

A manometer gives intermittent readings, taken only when needed. A transducer gives continuous monitoring, always shown on the monitor.

Does CVP increase or decrease in congestive heart failure, and why?

Increases, because the congested heart raises pressure in the atrium.

Does CVP increase or decrease in diarrhea, and why?

Decreases, from reduced blood/fluid volume.

Does CVP increase or decrease in shock, and why?

Decreases, mainly due to vasodilation.

Does CVP increase or decrease in DIC (disseminated intravascular coagulation)?

Decreases, due to widespread clotting and hemorrhage.

Does CVP increase or decrease in chronic kidney disease (CKD)?

Increases, due to fluid congestion.

Does CVP increase or decrease in Cushing's syndrome, and why?

Increases, from edema caused by increased aldosterone driving sodium and water retention.

Does CVP increase or decrease in diabetes insipidus, and why?

Decreases, due to large volumes of urine output

Does CVP increase or decrease in cirrhosis, and why?

Increases, from portal hypertension and fluid retention in the interstitial space.

Does CVP increase or decrease in oliguria, and why?

Increases, since fluid is retained in circulation instead of being excreted as urine.

What happens to CVP and BP in cardiac tamponade, and what triad should be assessed?

High CVP with LOW BP. Assess for Beck's triad: hypotension, JVD, and muffled heart sounds.

What CXR and ECG findings are associated with cardiac tamponade?

CXR: water bottle sign. ECG: decreased amplitude of the QRS complex.

Does CVP increase or decrease with massive hemorrhage (as in DHF)?

Decreases, from blood loss.

Why does circulating volume/CVP increase in nephrotic syndrome despite protein loss?

Decreased oncotic pressure lets fluid shift into tissues, which triggers sodium and water retention that increases circulating volume.

What happens to CVP with burns, and does it change over time?

Decreases initially from massive fluid/capillary leakage, then increases later during the fluid resuscitation phase.

What does diaphoresis usually indicate in terms of volume status?

A sign of shock (decreased perfusion).

What does an S3 heart sound suggest?

Increased ventricular filling and volume overload, commonly seen in heart failure.

Why does edema occur with elevated CVP?

Elevated venous pressure pushes fluid into the surrounding tissues, causing peripheral edema.

Why can crackles occur with elevated CVP?

Fluid congestion can accumulate in the lungs, producing crackles.

A patient has urine output 20 mL/hr, weak pulses, hypotension, lethargy, HR 96, and thirst. What's the nursing diagnosis?

Fluid volume deficit related to active fluid loss.

A patient has bounding pulses, BP 150/90, an 11-lb weight gain, and drinks 3 L a day. What's the nursing diagnosis?

Excess fluid volume related to excessive intake.

A patient has bounding pulses, an 11-lb weight gain, and cardiomegaly on CXR. What's the nursing diagnosis, and why impaired regulatory mechanism?

Excess fluid volume related to impaired regulatory mechanism, because the heart and kidneys, the body's main fluid regulators, are impaired.

What is the main action of vasopressors, and why are they used in shock?

They cause vasoconstriction, raising vascular resistance and arterial pressure so organs stay perfused. Shock's main problem is vasodilation and hypotension.

What is the main action of inotropes?

They strengthen cardiac contractions so blood circulates better, keeping organs perfused.