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CVCs are used frequently not only for assessment of CVP but also for adminis-
tration of drugs and fluids. Of course, CVCs are not considered as the primary route
for urgent and rapid fluid replacement. Instead, peripheral large-bore catheters are
considered for rapid fluid administration.
Many different indications have been cited for CVP; however, a number of them
are mentioned here, and a detailed list could be found in Table 4.1.
4.3.1 Indications for CVC Insertion and Usage
1. Fluid administration and management (including assessment of loading status,
patients with poor peripheral IV access).
2. Continuous renal replacement therapy and/or temporary hemodialysis (although
usual multi-lumen 7 F, 20 cm catheters have a much lower capacity for fluid
administration compared with usual peripheral IV access).
3. Diagnostic measurements (pure values and changing trends of cardiac loading
pressures).
4. Pharmacologic interventions (especially the vasoactive drugs or irritant drugs
and plasmapheresis or apheresis).
5. Other indications (like transvenous pacing).
4.3.2 Central Venous Pressure Curves
The CVP curve is composed of five main waves, namely, a, c, x, v, and y which are
the final result of interactions mainly occurring between right atrium (RA), right
Table 4.1 Indications and contraindications for central venous catheters (CVCs)
Indications
Administration of pharmaceuticals (esp. the vasoactive or irritant drugs)
Monitoring the hemodynamic parameters (esp. loading status including CVP)
Transvenous pacing
Rapid fluid administration (in trauma or in procedures mandating large fluid shift or blood loss)
Poor peripheral IV access
Frequent or rapid aspiration (blood aspiration for frequent venous sampling or rapid air
emboli aspiration in specific surgeries)
Total parenteral nutrition (TPN)
Continuous renal replacement therapy, temporary hemodialysis, plasmapheresis, or apheresis
Contraindications
Absolute contraindications
SVC syndrome causes CVC to be useless and possibly increases the CVC risks for the patient
Relative contraindications
Coagulopathies
Patients having pacemaker or ICD insertion in the 6 previous weeks
Anatomic abnormalities (due to coexisting pathologies or recent surgical manipulations
disturbing the normal anatomy of the region)
Carotid disease especially in the presence of contralateral carotid involvement
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ventricle (RV), and the tricuspid valve (TV); however, among them a, c, and v are
upward deflections, while x and y are downward deflections. These waves mainly
demonstrate the right atrial pressure (RAP) as the following order (Fig. 4.2):
a: Atrial contraction causes an increase in RAP; it appears just after P wave in
electrocardiography.
c: Isovolemic contraction of RV increases RAP and creates c wave.
x: RV contraction pulls TV away from RA and decreases RAP, so we would have a
downward deflection wave.
v: Blood fills RA during late RV systole which increases RAP and again produces
an upward deflection.
y: Finally TV opens and causes emptying of RA, so again we see a downward
deflection.
4.3.3 Technical Considerations for Insertion of CVC
There are a number of well-recognized approaches for CVC insertion, “internal
jugular vein” and “subclavian vein” being the two most common approaches while
the right internal jugular vein is more common than the left one, while some believe
that left internal jugular approach is as easy as the right side.
4.3.3.1 Right Internal Jugular Vein Approach
The internal jugular vein (IJV) was first described by English in the 1960s and is the
most frequently used approach for CVC insertion; it causes less complications, has
a straight course to the RA, and has lower chance for thoracic duct and pleural dome
puncture, both due to anatomic properties of right IJV, although some have claimed
P
ECG
Systole
Diastole
aa
c
v
yx
CVP
R
T
Fig. 4.2 CVP waves and the relation with ECG
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that the left IJV approach is as much easy. It also has a very high success rate
(>90 %) even in infants and children accompanied with very low rate of other
mechanical complications like arterial puncture, pneumothorax, and hematoma
needing surgical intervention compared with all the other methods. Even in ana-
tomically “difficult” patients, the IJV approach has a specific feasibility. The course
of IJV especially the right one is straight, short, and with distinct anatomical land-
marks; it is without venous valves until superior vena cava and right atrium and
could be reached by most anesthesiologist even during the operation time. Its most
common and easiest “central approach” described in 1970 by Daily et al. is even the
simplest one among all the right IJV access methods in which the needle tip is
inserted into the “apex of Sedillot’s triangle, which is between the sternal and cla-
vicular heads of sternocleidomastoid (SCM) and the related portion of the clavicle
located between the two SCM muscle heads.” See Fig. 4.3.
Correct sizing of the catheter length is a very challenging issue.
The following steps should be followed for insertion of CVC through right IJV:
1. Put the patient in supine position with a little leftward rotation of the head.
2. Gently extend the neck; excessive extension would distort the “favorable
anatomy.”
3. Check the anatomic landmark of the neck (Sedillot’s triangle) once more before
draping.
4. Use basic monitoring including electrocardiography (ECG), pulse oximetry
(SpO
2
), and noninvasive or invasive blood pressure measurement.
5. Use a “mild” degree of sedation if the patient is not anesthetized or not sedated
accompanied with supplemental oxygen.
6. Administer strict aseptic techniques including hand washing, using sterile gown
and gloves, and sterile preparation from the mastoid to the sternal notch (2 %
chlorhexidine is superior to others like 10 % povidone-iodine).
7. Drape the patient with a large drape.
8. Put the patient slightly in head-down position except for patients with cardio-
vascular or respiratory disease.
9. In awake patients, use 1 % lidocaine solution for local anesthesia using a 25 G
needle after another check of landmarks.
10. Use a 22 G finder needle to find IJV.
11. Introduce the 18 G needle from the apex of the Sedillot’s triangle from between
the two heads of SCM towards the ipsilateral nipple with a 30–45° angle from
the skin plane.
12. If you could not draw dark blood, relocate the needle a bit laterally or medially
in a fanwise model; beware of arterial puncture risk.
13. Check patency of the needle if there is not successful venous puncture yet; also,
check the anatomical landmarks once more.
14. The two venous walls of a central vein are at times compressed against the
needle; withdrawing the needle gently usually causes sudden filling of the
syringe in such cases.
15. After appropriate backflow of relatively dark blood, insert the guidewire
through the needle; there should not be any resistance in the course of
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guidewire insertion; otherwise, the guidewire path is not correct; usually the
guidewires used for adult CVCs are 0.032–0.035 mm, so the guidewire pas-
sage should be never forceful.
16. The blood flow should be non-pulsatile except for cases of severe tricuspid
regurgitation or high right ventricular pressure, in which the backflow of IJV
would be pulsatile; if you are doubtful regarding the blood flow to be arterial or
venous, attach a sterile stopcock to the 18 G needle, which has an extension tube
attached to one of its heads; ask a colleague to attach the other head of the exten-
sion tube to the pressure monitoring to rule out potential arterial puncture.
Fig. 4.3 A schematic
presentation of the right
anterior triangle (Sedillot’s
triangle) used for internal
jugular vein cannulation
when looking from above the
patient’s head. (a) The
anatomic landmarks of the
triangle, SCM
sternocleidomastoid muscle,
Lat lateral, Med medial. (b)
Anatomic location for needle
punctures near the apex of
triangle towards the
ipsilateral nipple
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17. The guidewire should be always in control, regarding both sterility of its distal
end and potential arrhythmias of its proximal head; the former needs protection
from contact with the unsterile adjacent objects, and the latter mandates careful
ECG monitoring; in most adult cases, guidewire advancement below 20 cm
prevents unwanted complications.
18. Withdraw the needle after guidewire installation; use a number 11 scalpel blade
before advancing the dilator (especially when a pulmonary artery catheter
“PAC” introducer sheath or a large-bore CVC is used); care should be taken not
to exert inappropriate force on the catheter; otherwise, guidewire would easily
be kinked; on the other hand, excessive dilator advancement would result in
unwanted vascular or tissue trauma.
19. After dilator removal, while the guidewire is still in place, insert the catheter while
caring to take the distal end of the guidewire out of the port of the CVC before the
catheter is fully inserted; loss of control over the distal part of guidewire could
result in catheter embolization, an unwanted complication discussed later.
20. Using this approach, CVC should be introduced no more than 15–17 cm in
adult men and 13–15 cm in adult women to prevent CVC-induced cardiac tam-
ponade (discussed later).
21. The CVC lines should be de-aired and washed to prevent clotting.
22. Sterile dressings (without any antibiotics) should be used in place.
23. Objective confirmation of the CVC tip which is done by CXR after catheter
placement; the tip of the catheter should be above the carina which is approxi-
mately at the level of T3–T4 thoracic spines, which is also equal to 3rd rib or
azygous vein.
4.3.3.2 Left Internal Jugular Approach (LIJV)
The technique is similar to right IJV; however, the dome of the left pleura is higher
than the right pleura, and also, thoracic duct passes from the left; these two ana-
tomic features increase the risk for two important complication: pneumothorax and
chylothorax. Chylothorax is exclusive to the left hemithorax. The LIJV is shorter
than the right IJV, but the venous path from the left side to superior vena cava is
longer than the right side. However, the chance for superior vena cava injury in left
IJV is higher than right IJV since the path of right IJV is straightforward compared
with left IJV.
4.3.3.3 Subclavian Approach
This approach has some specific features, more patient comfort, an easy approach,
and lower infection rate and often used for long-term IV therapy but not monitoring
purposes.
Method:
1. Monitor the patient, accompanied with supplemental oxygen and mild sedation.
2. Head-down the patient.
3. Rotate the head laterally.
4. Use a role beneath the two scapulae.
5. Use local anesthesia in a point just below the clavicle, between the lateral and
middle thirds of the clavicle.
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6. The 18 G needle should be passed below the clavicle being directed to the sternal
notch.
7. After appropriate backflow of relatively dark blood, insert the guidewire through
the needle.
8. Other steps are similar to internal jugular approach.
9. Due to the potential risk of vascular injury or pneumothorax, one should keep in
mind that a maximum of three tries from this approach is allowable, and also,
bilateral (right and left subclavian) tries are forbidden since bilateral try would
be potentially lethal.
4.3.3.4 External Jugular Vein
A simple, really less risky approach, though having lower chance for success; of
course, there are a few concerns for this approach:
1. Never use a dilator for these veins.
2. 90° abduction of the ipsilateral arm increases the success.
3. The vein course is sometimes tortuous, and the venous path could not be used for
introduction of the catheter in nearly 20 % of patients.
4.3.3.5 Femoral Vein
Usually used when IJV or subclavian approaches are not available (e.g., in neck
injuries or thoracic involvements). The femoral vein is entered in a place just medial
to the femoral artery pulse; however, the needle should be introduced to the vein
distal to the inguinal ligament to prevent the risk of retroperitoneal bleeding.
Besides, femoral artery or femoral nerve injury, infectious complications, and
thromboembolic complications are the main other potential complications of this
approach. Two different length catheters have been used in this approach: “40–
70 cm” and “15–20 cm” catheters; both are near to the SVC measurement but not
exactly the same figures.
4.3.3.6 Peripheral CVC
Peripherally inserted catheters as CVC have been used to decrease complications of
CVC; but there is no difference between the two methods regarding infection rate.
However, peripheral CVCs have more complications like “catheter tip malposition-
ing, thrombophlebitis, and catheter dysfunction”; hence, central CVCs seem to be
preferred over peripheral catheters.
4.3.4 Ultrasound-Guided CVC Insertion
This method was introduced for the first time in 1984 and could improve success
and decrease the rate of complications, so increasing patient safety, especially in
IJV approach and in inexperienced hands. Though adult patients are more frequently
said to benefit this method, ultrasound-guided CVC insertion has been shown effi-
cacious in pediatric patients. A 7.5–10 MHz probe, covered by a sterile sheath, used
by the nondominant hand, finds the transverse (short) axis at first in order to find IJV
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vein lumen, which is larger, laterally located, and non-pulsatile compared with the
medially located carotid artery; the transverse axis is also used for detection of the
needle entry to IJV lumen. Then, the longitudinal view (long axis) is used to confirm
the appropriate passage of the guidewire into the lumen of IJV. However, in other
approaches except for IJV, there is not much great utility for ultrasound-guided
CVC insertion because of the sonographic “shadows and distances” between the
skin and the vein lumen.
4.3.5 Complications of CVCs
One of the very common topics in everyday practice of cardiac patients is the minor
and major complications of CVCs; many complications have been attributed to
CVCs, and too many studies have been published in this topic; the majority of these
complications are not common; however, a few could potentially lead to major
events and even death. These complications are categorized in four main categories
and discussed more in the following paragraphs:
1. Mechanical (vascular injuries, tamponade, nerve injuries, pneumothorax, tissue
trauma, etc.)
2. Thromboembolic
3. Infection
4. Other complications
4.3.5.1 Mechanical Complications
These include mainly vascular injuries (arterial puncture, venous injuries), cardiac
tamponade, neural injury, tissue trauma, pneumothorax, and catheter or guidewire
embolization. Vascular injuries could be arterial or venous.
Arterial puncture is the most frequent among all acute complications, often
resulting in local hematoma, which usually resolves after a few minutes of local
compression. Few numbers of the patients (especially when major arteries includ-
ing aorta are injured) need more sophisticated care including emergent consult with
a vascular surgeon. If arterial puncture is unintentionally used instead of central
vein for catheter placement, the catheter should be removed urgently (except for
very unusual circumstances) to prevent unwanted organ embolizations including
CNS injuries. However, the risk of arterial bleeding at the puncture site is always
potentially serious, needing more vigorous assessments and possible interventions
by a vascular surgeon. If a central venous catheter is misplaced anatomically, the
location of the catheter tip should be assessed. If it is not in a potentially risky place,
we might withdraw the catheter; however, if the catheter tip is located in a risky
organ which could not be compressed after catheter removal, or if the course of
catheter passes through such an anatomic location, then the catheter should not be
removed before an emergent consult with a vascular surgeon.
Other vascular injuries are frequent and diverse including minor venous injuries,
hemomediastinum, hydromediastinum, hemothorax, hydrothorax, and chylothorax.
And finally, delayed vascular injuries have been reported including different types
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of fistula between veins, arteries, bronchus, or other adjacent tissues, all being rare
but needing vigorous attention and care.
Hemopericardium is the 2nd common and the most lethal complication of CVC
placement. It is usually due to perforation of right ventricle, right atrium, or the seg-
ment of superior vena cava located inside the pericardium. The rupture would cause
sudden cardiac tamponade blood or fluid tamponade. This is a delayed complication
of CVC occurring usually in the 1st week after CVC placement and is usually pre-
ceded by arrhythmia unresponsive to anti-arrhythmia treatments. Mortality rates
more than 80 % are reported for this complication. Would the clinician perform
objective documentation of the CVC tip location (i.e., by CXR), this lethal compli-
cation could be prevented in many cases.
Pneumothorax is another mechanical complication occurring more commonly after
subclavian approach; however, the IJV approach (especially the left IJV) could also
lead to pneumothorax though with a lower rate compared with subclavian approach.
Minor cases are treated with supportive care, while others need chest tube insertion.
Vigorous care should be devoted to high-risk patients especially those underlying
mechanical ventilation or those in whom multiple or bilateral punctures have been
done to prevent the occurrence of tension pneumothorax which is very lethal.
Nerve injuries could be seen mainly at the following sites: brachial plexus, stel-
late ganglion, and phrenic nerve. Chronic pain syndromes are also possible.
Tissue Trauma: Trauma due to needle, guidewire, dilator, or even the catheter
had been reported. Dilator-induced tissue or vascular injuries are much more impor-
tant since the dilators usually cause more harmful injuries than other items used in
CVC kits. However, large-bore lumen catheters could lead to tissue injuries; cata-
strophic results should be anticipated if central vessels or cardiac chambers are
injured or, in worst conditions, “ruptured” (see above).
Catheter or guidewire embolization usually mandates emergent consultation
with an interventionist or a surgeon. During CVC placement, guidewire could be
introduced inside the venous system unintentionally, so it is necessary that the clini-
cian take control of the distal end of the guidewire before introducing the whole
catheter into the venous system. Also, there are reports of partial catheter fracture;
both of these states could lead to catheter or guidewire embolization into the venous
system, cardiac chambers, or even the pulmonary veins, being dislodged in between
the lung tissues. The medical team should check any catheter fractures continually
in patients admitted in intensive care wards, especially when the patients are awake
and there is the possibility for spontaneous changes in body position. Another criti-
cal time for occurrence of this complication is at the time of CVC removal, which
mandates careful examination of the whole CVC length, and check for its tip to be
intact after withdrawing from the patient.
4.3.5.2 Thromboembolic Complications
These complications are more common in patients with femoral CVC and are low-
est in subclavian approach. The primary nidus can change to an infectious compli-
cation or may dislodge to the pulmonary vasculature; usually these complications
need surgical removal.
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4.3.5.3 Infectious Complications
Infectious complications are among the most common late complication of CVC,
with 30–50 % mortality. Strict adherence to aseptic techniques during catheter place-
ment is cornerstone of all preventing strategies for CVC infection. Using subclavian
approach, application of catheters coated with chlorhexidine and silver sulfadiazine
or rifampin and minocycline, and selection of single-use catheters have been demon-
strated as methods to decrease the rate of CVC-related infection. Also, the site of
catheter insertion could affect the incidence of infectious complications being less in
subclavian approach than other routes, though some controversies exist.
4.3.5.4 Other Complications
Arrhythmia is a very frequent and usually benign complication during CVC inser-
tion especially in Seldinger technique (due to the guidewire); however, there are
reported cases of malignant arrhythmias exactly at the time of CVC insertion, so
careful attention to patient’s rhythm and hemodynamic status is a main concern dur-
ing CVC insertion. However, the catheter itself could induce arrhythmias due to its
physical effects if not in an appropriate location, which could happen intra- or post-
operatively. Careful attention in the length of catheter entry is very important. Also,
objective catheter tip confirmation by CXR is an essential job, confirming the CVC
tip above the carina bifurcation; otherwise, the catheter should be a bit withdrawn in
such a way that its tip is not far beyond carina.
Bleeding and air emboli are often related to CVCs with large-bore lumens,
though other types of CVC may also have this side effect. Forgetting to secure the
lumen ports could result in unnoticed bleeding. If the patient is hypovolemic, this
complication would be manifested as air emboli entering the central venous circula-
tion through the nonsecured lumen. Air embolism is also possible during two other
situations besides unnoticed nonsecure ports; one is during catheter insertion, which
is usually accompanied with small volumes of air going through the needle to the
venous system, while the other situation is after CVC withdrawal which could be
accompanied with air embolization through the skin lumen and subcutaneous tunnel
created by after catheter removal. A compressed dressing with proper sealing could
prevent both potential air embolism and CVC site bleeding after CVC removal.
Misinterpretation of data and errors in interpretation of data could lead to erro-
neous results and potential untoward clinical outcomes. For prevention of such
erroneous judgments, the clinicians often do not rely only on the results of central
venous pressure recordings; instead, the trend of CVP changes, curve of CVP, other
measurements of filling pressures, jugular venous pressure figures, etc., are added
to the online readings of CVP to prevent such unwanted events (Daily et
al. 1970;
Knopp and Dailey 1977; Berghella et al. 1979; Tyden 1982; Ferguson et al. 1988;
Siradovic et al. 1988; Holmes et al. 1989; Kolodzik 1989; Meyer 1990; Heiss 1992;
Mansfield et al. 1994; Tesio et al. 1994; English et al. 1995; Reed et al. 1995; Kuhn
2001; Merrer et al. 2001; Asheim et al. 2002; Keenan 2002; Woodrow 2002; Hind
et al. 2003; Unal et al. 2003; Arai and Yamashita 2005; Botha et al. 2006; Di Iorio
et al. 2006; Karakitsos et al. 2006; Ash 2007; Chen et al. 2007; Harrigan et al. 2007;
Trieschmann et al. 2008; Brusasco et al. 2009; Kujur et al. 2009; Surov et al. 2009;
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Ishizuka et al. 2010; Kunizawa et al. 2010a, b; Omar et al. 2010; Furuya et al. 2011;
Kang et al. 2011; Kim et al. 2011, 2012; McGee et al. 2011; Uchida et al. 2011;
Urban et al. 2011; Boyce 2012; Calabria et al. 2012; Chopra et al. 2012; Ge et al.
2012; Godoy et al. 2012; Guleri et al. 2012; Hewlett and Rupp 2012; Lee and
Kamphuisen 2012; Liang et al. 2012; Linnemann and Lindhoff-Last 2012; Marik
et al. 2012; Miller and Maragakis 2012; Parienti et al. 2012; Pikwer et al. 2012;
Reems and Aumann 2012; Stone et al. 2012; Turi et al. 2013; Vats 2012; Walser
2012; Zhou et al. 2012; Gibson and Bodenham 2013).
4.4 Pulmonary Artery Pressure Monitoring
4.4.1 History
Pulmonary artery catheter (PAC) was reported first in 1970 by Dr. Swan and Dr.
Ganz; hence, the catheter is frequently known as the Swan-Ganz catheter. At that
time, this catheter could introduce a new field of online cardiovascular monitoring,
controlling the response to therapies and clinical data collection to the clinical world
which was not accessible in such a novel way till that time. Due to its novel data, its
use was rapidly increased during the following years both inside the operating
rooms and intensive care units for cardiac and noncardiac patients. So PAC could
help us retrieve a number of useful data which are not retrievable by other monitor-
ing devices like CVC-recorded pressure monitoring; these data are used for diag-
nostic and/or therapeutic uses, i.e., assessment of the effects of therapies.
4.4.2 Clinical Outcome of PAC Usage
During the recent years, there are an increasing number of evidence which question
the clinical and final clinical outcome of using PAC, creating an overwhelming load
of controversies in using this monitoring device, though some studies have confirm
the usefulness of PAC in decreasing mortality in critical patients. Some results of
these studies are discussed here briefly.
The negative studies claim that PAC could not decrease the overall mortality or
hospital length of stay in critical care patients; also, right heart catheterization in
ICU causes increased risk for severe end-organ complications and increased mortal-
ity, costs, and length of stay, in such a way that some studies have recommended
withdrawal of PAC from current clinical practice in adult ICU patients as a cost-
effective strategy; on the other hand, currently, many of the clinicians are seeking
newer, less invasive monitoring to be validated and used in practice instead of PAC;
among them, transesophageal echocardiography (TEE) could be named as one of
the most useful devices for such an application that gives us the needed online data
without potential risks of PAC; finally, these data at least recommend us not to use
PAC as a routine monitoring, especially in low-risk patients; on the other hand, the
positive studies confirm the beneficial role of PAC in decreasing mortality.
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