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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