7

Cardiac Catheterizati

on

Central Venous

Pressure

Definition:Cardiac catheterization (heart cath) is the insertion of a catheter into a chamber or vessel of the heart. This is done for both investigational and interventional purposes.

This is a procedure to examine blood flow to the heart and test how well the heart is pumping. 

Preparation:Patients should give the physician or nurse a complete list of their regular medications, including aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), because they can affect blood clotting. Diabetics who are taking either metformin or insulin to control their diabetes should inform the physician, as these drugs may need to have their dosages changed before the procedure.

Patients should also notify staff members of any allergies to shellfish containing iodine, iodine itself, or the dyes commonly used as contrast agents before cardiac catheterization.

Because cardiac catheterization is considered surgery, the patient will be instructed to fast for at least six hours prior to the procedure. A mild sedative may be administered about an hour before the procedure to help the patient relax. If the catheter is to be inserted through the groin, the area around the patient's groin will be shaved and cleansed with an antiseptic solution.

Goals:This technique has several goals:

•confirm the presence of a suspected heart ailment•quantify the severity of the disease and its effect on the heart•seek out the cause of a symptom such as shortness of breath or signs of cardiac insufficiency•make a patient assessment prior to heart surgery

Investigative techniques used with coronary catheterization

•to measure intracardiac and intravascular blood pressures•to take tissue samples for biopsy•to inject various agents for measuring blood flow in the heart; also to detect and quantify the presence of an intracardiac shunt•to inject contrast agents in order to study the shape of the heart vessels and chambers and how they change as the heart beats

Indications:Cardiac catheterization is performed to:

• Diagnose or evaluate coronary artery disease• Diagnose or evaluate congenital heart defects•Diagnose or evaluate problems with the heart valves•Diagnose causes of heart failure or cardiomyopathy

The following may also be performed using cardiac catheterization:

•Repair of certain types of heart defects•Repair of a stuck (stenotic) heart valve•Opening of blocked arteries or grafts in the heart

Contraindications:

o Renal insufficiencyo Coagulopathyo Fevero Systemic infectiono Uncontrolled arrhythmia or hypertensiono Uncompensated heart failureo Radiopaque dye allergies in patients who have not been appropriately premedicated

How its done:

Implementation:•The patient is placed supine on padded table and his heart rate and rhythm, respiratory status, and blood pressure are monitored throughout theprocedure. •An I.V. line is started, if not already in place, and a local anesthetic is injected at the insertion site.•A small incision is made into the artery or vein, depending on whether the test is for the left or right.

•The catheter is passed through the sheath into the vessel and guided using fluoroscopy.

•In the right-sided catheterization, the

catheter is inserted into the antecubital or femoral

vein and advanced through the vena cava

into the right side of the heart and into the pulmonary artery.

•If left-sided heart catheterization, the catheter is inserted into the brachial or femoral artery and advanced retrograde through the aorta into the coronary artery ostium and left ventricle.•When the catheter is in place, contrast medium is injected to make visible the cardiac vessels and structures.

•Nitroglycerin is given to eliminate catheter-induced spasm or watch its effect on the coronary arteries.•After the catheter is removed, direct pressure is applied to the incision site until bleeding stops, and a sterile dressing is applied.

Complications:

•Heart attack or stroke •Abnormal heartbeat (cardiac arrhythmia) •Puncture of a blood vessel or of the heart •Bleeding, blood clot, or infection at the catheter insertion site •A blocked blood vessel in the arm or leg in which the catheter was inserted

•An allergic reaction to the X-ray dye •Ineffective endocarditis in a patient with vulvular heart disease.•Myocardial infarction, arrhythmias, cardiac tamponade, pulmonary edema, hematoma, blood loss, adverse reaction to contrast media, and vasovagal response.

Because some of these problems may be life

threatening, heart catheterization should always be done in a hospital that has the necessary equipment and personnel to deal with any complications

immediately.

Certain patients have a higher-than-average risk of complications. These include infants

younger than 1 month, people older than 80

years, people with very poor heart function, and

people with certain chronic illnesses, such

as kidney failure, insulin-dependent

diabetes, and severe lung disease.

Nursing Responsibilities:

•Monitor the patient’s heart rate and rhythm, respiratory and pulse rates, and blood pressure frequently.•Monitor the patient’s vital signs every 15 minutes for 2 hours after the procedure, every 30 minutes for the next 2 hours, and then every hour for 2 hours.•If no hematoma or other problems arise, begin monitoring every 4 hours. If vital signs are unstable, check every 5 minutes and notify the practitioner.

•Observe the insertion site for a hematoma or blood loss. Additional compression may be necessary to control bleeding.•Check the patient’s color, skin temperature, and peripheral pulse below the puncture site.•Enforce bed rest for 8 hours. If the femoral route was used for catheter insertion, keep the patient’s leg extended for 6 to 8 hours.

•If medications were withheld before the test, check with the practiotner about

resuming their administration.•Administer prescribed analgesics.

•Make sure a posttest ECG is scheduled to check for possible myocardial damage.

Definition:Blood from systemic veins flows into the right atrium; the pressure in the right atrium is the central venous pressure (CVP). CVP is determined by the function of the right heart and the pressure of venous blood in the vena cava.

Central venous pressure is considered a direct measurement of the blood pressure in the right atrium and vena cava. It is acquired by threading a central venous catheter (subclavian double lumen central line shown) into any of several large veins. It is threaded so that the tip of the catheter rests in the lower third of the superior vena cava. The pressure monitoring assembly is attached to the distal port of a multilumen central vein catheter.

Sites for Insertion:

Materials:•Sterile pack and antiseptic solution•Local anaesthetic - e.g. 5ml lignocaine 1% solution •Appropriate CV catheter for age/route/purpose •Syringes and needles •Saline or heparinised saline to prime and flush the line after insertion •Suture material - e.g. 2/0 silk on a straight needle

•Sterile dressing •Shaving equipment for the area if very hairy (especially the femoral) •Facility for chest X-ray if available •Additional equipment required for CVP measurement includes: manometer tubing, a 3-way stopcock, sterile saline, a fluid administration set, a spirit level and a scale graduated in centimeters

Preparations:Assisting with CVP placement•Adhere to institutional Policy and Procedure.•Obtain history and assess the patient.•Explain the procedure to the patient, include:

local anesthetictrendelenberg positioningdrapinglimit movementneed to maintain sterile field.post procedure chest X-ray

•Obtain a sterile, flushed and pressurized transducer assembly•Obtain the catheter size, style and length ordered.•Obtain supplies:

MasksSterile glovesLine insertion kitHeparin flush per policy

•Position patient supine on bed capable of trendelenberg position•Prepare for post procedure chest X-ray

Factors Affecting CVP:-    Systemic vasodilatation and hypovolaemia,      which leads to reduced venous return in the      vena cava and reduced RAP-    Right ventricular failure-    Tricuspid and Pulmonary valve disease-    Pulmonary hypertension-    Right ventricular dysfunction and pulmonary hypertension leads to raised    right atrial pressure, as does tricuspid and  pulmonary stenosis.

Indications:-    Systemic vasodilatation and hypovolaemia,      which leads to reduced venous return in the      vena cava and reduced RAP-    Right ventricular failure-    Tricuspid and Pulmonary valve disease-    Pulmonary hypertension-    Right ventricular dysfunction and pulmonary hypertension leads to raised    right atrial pressure, as does tricuspid and  pulmonary stenosis.

Normal CVP Measurements:

-    The normal CVP is between 5 – 10 cm of H2O (it increases 3 – 5 cm H2O when patient is being ventilated)-    CVP normal range:-    (2-5) mmHg-     (3-8)cm H2O

Increase of CVP

-    Over hydration -    Right-sided heart failure -    Cardiac tamponade-    Constrictive pericarditis-    Pulmonary hypertension-    Tricuspid stenosis and regurgitation-    Stroke volume is high

CVP Reading is High

Decrease of CVP

-    Hypovolemia-    Decreased venous return-    Excessive veno or vasodilation-    Shock ?-    If the measure is less than 5 cm water that mean that the circulating volume is decrease.

CVP Reading is Low

Complications (Immediate):

-    Hemothorax-    Pneumothorax: most common, noticed after CXR, “hypoxemia and absent breath sound” requires chest tube placement-    Bleeding : More common in patients with  coagulopathy“easily control femoral”

-    Arterial puncture-    Vessel erosion: Large vessel perforation “Dialysis”                         -    Nerve Injury-    Dysrhythmias-    Catheter malplacement-    Embolus-    Cardiac tamponade

Complications (Delayed):

-    Dysrhythmias-    Infection “Late, Femoral > IJ > subclavian-    Catheter malplacement-    Vessel erosion-    Embolus-    Cardiac tamponade -    Thrombosis

Nursing Responsibility:Insertion CVL -    Patient position: -    Patient is moved to the side of the bed so physician would not lean over-    The bed is high enough so physician would not have to stoop over-    Patient should be flat without a pillow, Trendelenburg position if patient is hypovolemic-    The head is turned away from the side of the procedure-    Wrist restraints if necessary

The Procedure-    Skin preparation:-    Prepare before putting sterile gloves -    Allow time for the sterilizing agent to dry-   Drape:-    Large enough  and Handed sterilely by the assistant-    Hole in the area of placement-    Prepare the tray:-    Prepare the equipment before starting-    Anesthesia: -    Use local anesthesia with lidocaine

AFTER THE INSERTION

-    Dispose all sharps-    Place an occlusive sterile dressing -    Flush lumens to maintain patency-    Obtain a chest x-ray (ask for order if physician doesn’t mention it)-    Monitor site for bleeding-    Assess breath sounds-    Assess circulation-    Assess for hematoma-    Document insertion, site, dressing and flushing