CENTRAL VENOUS CATHETERSBy Dr AVIJIT KUMAR PRUSTY,

DEPT OF ANAESTHESIOLOGY AND CRITICAL CARE,

SCB MEDICAL COLLEGE,CTCGUIDE-ASSO PROF DR BASANT K PRADHAN

What is cvp ? CVP is the pressure measured at the

junction of the superior venae cavae and the right atrium.

It reflects the driving force for filling of the right atrium & ventricle.

CONTD… Normal CVP in an awake , spontaneously

breathing patient - 1-7 mmHg or 5-10 cm H2O.

Mechanical ventilation- 3-5 cm H2O higher.

Historical background

1863 •Chauveau & Mary ( Paris ). •Developed a special double lumen catheter. •Systemic study, description & interpretation of intracardiac pressure recordings in horse.

1876 •Claude Bernard ( France ). • First cardiac catheterisation.

1949 •Duffy. •Introduced a catheter into the IVC through femoral vein.

Historical background contd…

1952 •Aubaniac.•Subclavian vein cannulation.

1953 •Seldinger.•CVP Catheter replacement method using guidewire.

1969 •English et al.•IJV cannulation.

Methods to measure cvp

1. Indirect assessment- Inspection of jugular venous pulsations

in neck.

2. Direct assessment- Fluid filled manometer connected to

central venous catheter. Caliberated transducer.

Methods to measure cvp contd...

1. Inspection of jugular venous pulsations in neck.

WHY IJV=No valves b/w rt. atrium & IJV. Degree of distention & venous wave form –can

give information about rt atrial cardiac function.

Fig. showing measurement of jvp

DISADV OF INDIRECT ASSESMENT

Jugular veins may be impossible to identify in up to 20% of patients, and the bedside diagnosis of low, normal, or high CVP is often inaccurate, particularly in critically ill patients.

This problem is compounded in the perioperative period

As a result, direct measurement of CVP is frequently necessary in hemodynamically unstable patients and those undergoing major operations

DIRECT ASSESMENT1. Fluid filled manometer connected to

central venous catheter- measured using a column of water in a marked manometer.

CVP is the height of the column in cms of H2O when the column is at the level of right atrium.

Advantage- simplicity to measure.

Disadvantage- Inability to analyze the CVP waveform.-Relatively slow response of the water column to changes in intrathoracic pressure.

measurement of CVP

METHODS OF DIRECT CVP MONITORING

transducer system: enables continuous readings which are displayed on a monitor.

MONITORING WITH TRANSDUCERS

Transducers enable the pressure readings from invasive monitoring to be displayed on a monitor

To maintain patency of the cannula a bag of normal saline or heparinised saline should be connected to the transducer tubing and kept under continuous pressure of 300mmHg thus facilitating a continuous flush of 3mls/hr or it can be flushed intermittently manually.

PROCEDURE FOR CVP MEASUREMENT USING A TRANSDUCER

THE CVP WAVEFORM The CVP waveform reflects changes in

right atrial pressure during the cardiac cycle

CVP The CVP waveform consists of five phasic

events, three peaks (a, c, v) and two descents (x, y)

TYPE OF WAVE CAUSE CARDIAC CYCLE

a wave Atrial contraction DIASTOLE

c wave Bulging of tricuspid valve into RA during IVC

SYSTOLE

X descent Atrial relaxation SYSTOLE

V wave Filling of RA L/T rise in pressure

SYSTOLE

Y descent Opening of Tricuspid valve

DIASTOLE

Various pathophysiologic conditions may be

diagnosed or confirmed by examination of the CVP

waveform

Atrial fibrillation obliterates the a wave, increases the c wave and preserves the v wave and y descent. This arrhythmia also causes variation in the electrocardiographic (ECG) R-R interval and left ventricular stroke volume, which can be seen in the ECG and arterial (ART) pressure traces

Isorhythmic atrioventricular dissociation. In contrast to the normal end-diastolic a wave in the CVP trace (left panel), an early systolic cannon wave is inscribed (*, right panel). Reduced ventricular filling accompanying this arrhythmia causes a decreased arterial blood pressure.

TRICUSPID REGURGITATION INCREASES CVP AND THE WAVEFORM DISPLAYS A TALL SYSTOLIC C-V WAVE THAT OBLITERATES THE X DESCENT

TRICUSPID STENOSIS ALSO INCREASES MEAN CVP, BUT THE CHARACTERISTIC VENOUS WAVEFORM IS DIFFERENT FROM THE ONE SEEN IN TRICUSPID REGURGITATION. THE DIASTOLIC Y DESCENT IS ATTENUATED AND THE END-DIASTOLIC A WAVE IS PROMINENT.

DURING POSITIVE PRESSURE VENTILATION, ONSET OF INSPIRATION (ARROWS) CAUSES AN INCREASE IN INTRATHORACIC PRESSURE. CVP IS STILL RECORDED AT END-EXPIRATION (MEAN CVP 8 MMHG).

DURING SPONTANEOUS VENTILATION, ONSET OF INSPIRATION (ARROWS) CAUSES A REDUCTION IN INTRATHORACIC PRESSURE, WHICH IS TRANSMITTED TO BOTH THE CVP AND THE PULMONARY ARTERY PRESSURE (PAP) WAVEFORMS. CVP SHOULD BE RECORDED AT END-EXPIRATION (MEAN CVP 14 MMHG).

WHAT IS A CENTRAL LINE

It is a catheter that provides venous access via the superior vena cava or right atrium

What is a Central Venous Catheter?

The tip of the CVC usually rests in the Cavo-Atrial Junction (CAJ).

Femorally inserted CVCs have the tip lying in the Inferior Vena Cava approximately at the level of the diaphragm.

WHERE ARE CENTRAL VENOUS CATHETERS INSERTED?

INDICATIONS OF CENTRAL LINE

ACCORDING TO DURATION

In patients with severe bleeding diatheses, it is best to choose a puncture site at which bleeding from the vein or adjacent artery is easily detected and controlled with local compression. In such a patient, an internal or external jugular approach would be preferable to a subclavian site.

Likewise, patients with severe emphysema or others who would be severely compromised by pneumothorax would be better candidates for internal jugular than subclavian cannulation because of the higher risk with the latter approach.

If transvenous cardiac pacing is required in an emergency situation, catheterization of the right internal jugular vein is recommended because it provides the most direct route to the right ventricle.

Trauma patients with their necks immobilized in a hard cervical collar are best resuscitated via a femoral or subclavian approach; the latter may be used even more safely if the risk of pneumothorax is obviated by prior placement of a thoracostomy tube.

Technique Seldinger technique

Use introducing needle to locate vein Wire is threaded through the needle Needle is removed Skin and vessel are dilated Catheter is placed over the wire Wire is removed Catheter is secured in place

Location Advantage Disadvantage

Internal Jugular

• Bleeding can be recognized and controlled• Malposition is rare• Less risk of pneumothorax

• Risk of carotid artery puncture

Femoral • Easy to find vein• No risk of pneumothorax• Preferred site for emergencies and CPR• Fewer bad complications

• Highest risk of infection• Risk of DVT• Not good for ambulatory patients

Subclavian • Most comfortable for conscious patients

• Highest risk of PTX, should not do on intubated pts• Should not be done if < 2 years• Vein is non-compressible

Confirmation of cvp catheter

After surgery, however, the position of the catheter tip must be confirmed radiographically.

Catheter tips located within the heart or below the pericardial reflection of the superior vena cava increase the risk for cardiac perforation and fatal cardiac tamponade.

Ideally, the catheter tip should lie within the superior vena cava, parallel to the vessel walls, and be positioned below the inferior border of the clavicles and abovethe level of the third rib, the T4 to T5 interspace, the azygos vein, the tracheal carina, or the takeoff of the right mainstem bronchus

The Internal Jugular Vein The internal jugular vein (IJV) is most

frequently chosen site for CVC insertion. Many approaches have been described

depending on the level of the neck at which the vein is punctured.

A high approach reduces the risk of pneumothorax but increases the risk on arterial puncture. For lower approaches the converse is true.

With experience this route has a low incidence of complications

Internal Jugular Approach

PositioningRight side preferredTrendelenburg positionHead turned slightly away from side of venipuncture.

Subclavian Approach Positioning

Right side preferredSupine position, head neutral, arm adducted

Trendelenburg (10-15 degrees)

Femoral Approach Positioning

Supine Needle placement

Medial to femoral artery Needle held at 45 degree angle Skin insertion 2 cm below inguinal

ligamentAim toward umbilicus

Femoral artery

Femoral nerve

Femoral Vein

NAVEL

TYPES OF CENTRAL LINES PICC

– Peripherally Inserted Central IV Catheter Usually inserted in the upper arm Catheter tip is in the distal superior

vena cava like all other central lines

PICC

TUNNELED CATHETER

Hickman, Broviac, and Leonard Catheters – Open-ended, tunneled central lines

Hickman catheters can be 1, 2, or 3 lumen The lumens may all be identically sized, or

The lumens may be of different sizes Broviac catheters are all single lumen

catheters Leonard catheters have 2 lumens of identical

size

IVADS• Implanted subcutaneously instead of patient having a port

outside of body Mediport and Portacaths are the most common No dressing is required Accessed by a Huber needle Flushed with Heparin More expensive

A portacath or "port" is comprised of two components, a self-sealing injection port and a catheter that enters the vein. The port and catheter are placed entirely under the skin using a small incision.

Mediport or Portacath

Mediport or Portacath There will be a bump

on the chest wall where the injection port is located. This is the site where the access Huber needle is placed.

Once port is deaccessed, it needs a MONTHLY flush with 5ml of heparin (100 units/ml) to keep it patent.

Power Port The Power Port

Designed for power injections

Withstands injections of 5ml/sec @ 300 psi

The unique triangular shape

Requires Heparin flush

REMOVAL OF CENTRAL LINE

THIS IS AN ASEPTIC PROCEDURE THE PATIENT SHOULD BE SUPINE WITH HEAD

TILTED DOWN ENSURE NO DRUGS ARE ATTACHED AND

RUNNING VIA THE CENTRAL LINE REMOVE DRESSING CUT THE STITCHES SLOWLY REMOVE THE CATHETER IF THERE IS RESISTENCE THEN CALL FOR

ASSISTANCE APPLY DIGITAL PRESSURE WITH GAUZE UNTIL

BLEEDING STOPS DRESS WITH GAUZE AND CLEAR DRESSING EG

TEGADERM

COMPLICATIONS1.Acute Procedural2. Sub-acute Infection3. Chronic Infection,Catheterfragmentation,Non-function

COMPLICATIONS:ACUTE

1. Spasm 4. Pneumothorax

2. Access failure 5. Malposition

3. Arterial puncture 6. Air embolus

7.hemothorax,chylothorax

AIR EMBOLUS: SYMPTOMS1. Respiratory distress2. Increased heart rate3. pulse5. Cyanosis4. Dip in the level of consciousness

AIR EMBOLUS: TREATMENT

1. Left lateral decubitus (Durant’s) Position2 100% O23. Vasopressin if necessary4. Chest compression5. Aspiration through catheter +/- Mortality decreases from 90% 30% with conventional treatment

COMPLICATIONS:CHRONIC

1. Infection

2. Catheter fragmentation

3. Non-function

Complications Dysrhythmias Catheter malplacement Catheter rupture Embolus Cardiac tamponade Catheter related infection Thrombosis Hydrothorax

Evidence-Based Strategies Selected to Reduce CLA-BSIs

1. Hand hygiene2. Maximal sterile barriers3. Chlorhexidine for skin asepsis4. Avoid femoral lines5. Avoid/remove unnecessary lines

Hand Hygiene Cornerstone of any

infection prevention program

Many studies have shown that improvement in hand hygiene significantly decreases a variety of infectious complications

Hand Hygiene

Use of waterless alcohol-base hand rub Most effective and

efficient method for hand antisepsis against bacterial pathogens

When hands are visibly soiled, they should be washed with soap and water

Efficacy of Hand Hygiene Preparations in

Killing Bacteria

Good Better Best

Plain Soap Antimicrobial soap

Alcohol-based handrub

Maximal Sterile Barriers

One study found a 6-fold higher rate of catheter-related septicemia when minimal sterile barriers (sterile gloves and small drape) were used instead of maximal sterile barriers

Raad II, Hohn H, Gilbreath J, et al. Prevention of central venous catheter-related infections by using maximal sterile barrier precautions during insertion. Infect Control Hosp Epidemiol. 1994;15:231–238.

Chlorhexidine for Skin Asepsis

Studies have compared chlorhexidine gluconate (CHG) versus povidone iodine as a skin antiseptic for catheter insertion and routine insertion site care

Recent meta-analysis, the use of CHG rather than povidone iodine was found to reduce the risk of CLA-BSIs by approximately 50% in hospitalized patients who required short term catheterization

Chaiyakunapruk N, Veenstra, DL, Lipsky BA, Saint S. Chlorhexidine compared with povidone-iodine solution for vascular catheter-site care: a meta-analysis. Ann Intern Med. 2002;136:792–801.

TYPES OF INFECTION

1. Cutaneous - pain, erythema, swelling, +/- exudate2. Bacteremia - fever, leukocytosis and positive blood cultures3. Septic thrombophlebitis - bacteremia, thrombosis and purulent discharge

INFECTION CAUSATIVE ORGANISMS

Staph epidermidis 25-50%

Staph aureus 25%

Candida 5-10%

INFECTIONSeptic thrombophlebitis - remove catheter Cutaneous - local treatment Bacteremia -

1. IV antibiotics 48 -72 hoursif improved - keep catheterif no change, worse or recursremove catheter or2. Exchange catheter over wire, 85% cure with treatment

INFECTIONContinue to treat infection for 10 - 14 days

If ineffective - try locking with thrombolytics between antibiotic doses and administer antibiotics through catheters

Discharge Teaching For The Patient With A CVC

Proper handwashing and principles of sterile technique

Flushing and cap change procedure and frequency

Observation of cath and insertion site

When to call the physician

Temp of 100.5F or greaterChills, dyspnea, dizzinessPain, redness, swelling, or

drainage at siteUnresolved resistance, pain or

fluid leaking while flushingExcessive bleeding at siteChange in length of external cathSwelling in neck, face, chest, or

arm