**4. Catheterization-related complications**


Irrespective of the type (non-tunneled or tunneled) or design (straight or with formed shape), their use is likely to be associated with complications (Table 4) (Morgan 2001, Ross 2001).

Table 4. Complications of central venous catheters insertion

The incidence of complications reaches 5.9% with catheter insertion based only on topographic anatomy even with experienced clinicians (McDowell et al 1993). In contrast, the incidence of procedure-related complications in central venous catheterization under ultrasound guidance is only 0.8% (Trerotola et al 1997). Ultrasound-guided catheterization also limits the incidence of failures related to catheter insertion and reduces complications and necessity of multiple punctures of a vessel (Randolph et al 1996). Early complications which are mainly "surgical" include pneumothorax, pleural or mediastinal hemotoma, air embolism, thoracic tract injury, damage to nervous structures within the neck and thoracic region, puncture of the cardiac cavities, or cardiac arrest (Feldman et al 1996) (Figure 1). Non-surgical complications include cardiac arrhythmia and insertion site infection.

Acute and Chronic Catheter in Hemodialysis 113

dysfunction is frequently associated with recirculation that exerts a deleterious effect on

Leakage of infusate from

tenderness, engorged vein

Unable to infuse and/or

Unable to infuse and/or

Able to infuse but not withdraw blood

the insertion site, swelling, pain,

withdraw blood

withdraw blood

**Complications Features Symptoms**

Fibrin from vessel wall injury connected to fibrin-coated catheter leading to increased risk of venous

Fibrin forms inside the catheter lumen causing partial or completion

Fibrin adheres to the external surface encasing the catheter and frequently extending the length of the catheter; thrombi trapped between sheath and

catheter causing partial occlusion (fibrin tail acts as an one-way valve)

Table 5. Different thrombotic occlusive complications related to central venous catheter for

Before the tunneled CVC thrombosis occurs, prophylactic inhibition of coagulation cascade should be considered. The earlier results of various antiplatelet agents and anticoagulation were not encouraging. Better patency has been maintained with catheter locking solutions between dialysis sessions. The standard protocol has been heparin instillation (1000 to 10000 units/ml) into the lumens in a volume sufficient to fill to the lumen tip (the lock). The heparin concentration is reduced because catheter lumens have increased in volume so as to reduce the possibility of unintentional systemic anticoagulation. Trisodium citrate with its antithrombotic and potentially antibacterial properties has also been tested as a locking solution. The American Society of Diagnostic and Interventional Nephrology Clinical Practice Committee recommends using a locking solution of 1000 units/ml heparin or 4%

Most recently, a Canadian multicenter study showed the once weekly use of recombinant plasminogen activator (1 mg in each lumen), as compared with heparin (5000 units/ml) thrice weekly, as a locking solution for CVC significantly reduced the incidence of catheter

Mural thrombosis in the superior vena cava and the right atrial wall associated with CVC placement is detected in one-third of patients but often remains asymptomatic [26]. Treatment by infusion of a fibrinolytic agent produces good results but angioplasty and

The incidence of central vein stenosis is considerable. As with fibrin sheath, central vein stenosis should be identified with a superior vena cavogram performed by removing the old

dialysis efficiency and patient outcome (Leblanc et al 1997).

thrombosis

occlusion

catheter tip

Fibrin tail or flap Fibrin extends from the end of the

trisodium citrate to maintain CVC patency (Fuchs et al 1999).

dysfunction and bacteremia (Hemmelgarn et al 2011).

stenting may be required for organized thrombosis.

**4.2 Central thrombosis formation** 

**4.3 Central vein stenosis** 

Mural thrombus

Intraluminal thrombus

Fibrin sheath

dialysis

Fig. 1. Plain Chest Xray showing a CVC placed in the left internal jugular vein protruding out of the vessel wall (arrow)

Long-term complications are equally important. The common ones are thrombotic complications, vascular stenosis and catheter-related bacteremia (CRB). To reduce their complications, the internal surface of catheters is often coated with heparin. Coating or impregnation of catheters with silver salts and antibiotics reduces the colonization of bacteria.

#### **4.1 Catheter dysfunction**

The 2006 National Kidney Foundation K/DOQI guidelines defines access dysfunction as the inability to achieve blood flow (Qb) ≥ 300 ml/min during the first 60 minutes of hemodialysis despite at least one attempt to improve flow (National Kidney Foundation 2006). Since then, larger bore catheter design allows much higher Qb (> 400 ml/min) to be achieved at the same prepump pressure. Hence, waiting until Qb declines to 300 ml/min in these catheters may be inappropriate, missing the opportunity to detect catheter dysfunction earlier.

Early identification of catheter dysfunction enables prompt intervention and salvage. Catheter occlusion can be caused by kinking or malposition and these may be detected during the first hemodialysis session. Other causes of catheter dysfunction include leakage, drug precipitation, thrombus formation and growth of a fibrin sheath. Thrombus-related occlusion typically occurs late either with or without a fibrin sheath. The clinical features of different thrombotic occlusive complications are summarized in Table 5. Catheter

Fig. 1. Plain Chest Xray showing a CVC placed in the left internal jugular vein protruding

Long-term complications are equally important. The common ones are thrombotic complications, vascular stenosis and catheter-related bacteremia (CRB). To reduce their complications, the internal surface of catheters is often coated with heparin. Coating or impregnation of catheters with silver salts and antibiotics reduces the colonization of

The 2006 National Kidney Foundation K/DOQI guidelines defines access dysfunction as the inability to achieve blood flow (Qb) ≥ 300 ml/min during the first 60 minutes of hemodialysis despite at least one attempt to improve flow (National Kidney Foundation 2006). Since then, larger bore catheter design allows much higher Qb (> 400 ml/min) to be achieved at the same prepump pressure. Hence, waiting until Qb declines to 300 ml/min in these catheters may be

Early identification of catheter dysfunction enables prompt intervention and salvage. Catheter occlusion can be caused by kinking or malposition and these may be detected during the first hemodialysis session. Other causes of catheter dysfunction include leakage, drug precipitation, thrombus formation and growth of a fibrin sheath. Thrombus-related occlusion typically occurs late either with or without a fibrin sheath. The clinical features of different thrombotic occlusive complications are summarized in Table 5. Catheter

inappropriate, missing the opportunity to detect catheter dysfunction earlier.

out of the vessel wall (arrow)

**4.1 Catheter dysfunction** 

bacteria.


dysfunction is frequently associated with recirculation that exerts a deleterious effect on dialysis efficiency and patient outcome (Leblanc et al 1997).

Table 5. Different thrombotic occlusive complications related to central venous catheter for dialysis

Before the tunneled CVC thrombosis occurs, prophylactic inhibition of coagulation cascade should be considered. The earlier results of various antiplatelet agents and anticoagulation were not encouraging. Better patency has been maintained with catheter locking solutions between dialysis sessions. The standard protocol has been heparin instillation (1000 to 10000 units/ml) into the lumens in a volume sufficient to fill to the lumen tip (the lock). The heparin concentration is reduced because catheter lumens have increased in volume so as to reduce the possibility of unintentional systemic anticoagulation. Trisodium citrate with its antithrombotic and potentially antibacterial properties has also been tested as a locking solution. The American Society of Diagnostic and Interventional Nephrology Clinical Practice Committee recommends using a locking solution of 1000 units/ml heparin or 4% trisodium citrate to maintain CVC patency (Fuchs et al 1999).

Most recently, a Canadian multicenter study showed the once weekly use of recombinant plasminogen activator (1 mg in each lumen), as compared with heparin (5000 units/ml) thrice weekly, as a locking solution for CVC significantly reduced the incidence of catheter dysfunction and bacteremia (Hemmelgarn et al 2011).

#### **4.2 Central thrombosis formation**

Mural thrombosis in the superior vena cava and the right atrial wall associated with CVC placement is detected in one-third of patients but often remains asymptomatic [26]. Treatment by infusion of a fibrinolytic agent produces good results but angioplasty and stenting may be required for organized thrombosis.

### **4.3 Central vein stenosis**

The incidence of central vein stenosis is considerable. As with fibrin sheath, central vein stenosis should be identified with a superior vena cavogram performed by removing the old

Acute and Chronic Catheter in Hemodialysis 115

at a rate of 17 ml/hour through each port x 3 hours), mechanical stripping using a snare inserted via the femoral vein by exchange of catheter over a guidewire (Suhocki et al 1996, Faintuch et al 2008, Goldberg et al 1985). Diverse degree of success in fibrin sheath stripping

Fig. 3. (A) A fibrin sheath (arrow) formed inside the lumen of the CVC. (B) A

permcathogram done showing a persisting filling defect (arrow) in the catheter lumen and

Catheter infection is a major cause of morbidity and mortality responsible for 6-28% of catheter failures (Bagui et al 2007). Diagnosis of catheter-related bacteremia (CRB) requires at least one of the following criteria: (a) clinical exit site infection with evidence of inflammation within 2 cm of sites; (b) definite organism grew from blood culture and catheter with no other apparent source of infection; (c) probable blood stream infection with defervescence after catheter removal when both blood and catheter tip infection is not confirmed in a symptomatic patients with no apparent source of infection; (d) possible blood stream infection in a symptomatic patients with defervescence after catheter removal,

The causative organisms are predominantly gram positive (~50%), gram negative bacilli (~25%) or polymicrobial (~20%). The most common occurrence is through the migration of skin organisms along the external surface of the catheter from the exit site wound or via the catheter lumen due to breakdown of aseptic technique. The organism can be embedded in a biofilm layer that confers protection from antibiotic therapy (Passerini et al 1992). Infection

is reported from different centers.

reflux of the contrast at the catheter tip.

**4.5 Catheter-related bacteremia** 

but remains culture negative.

catheter over the working guidewire followed by a pigtail catheter insertion (Figure 2). The management of central stenosis is evolving. Whenever found, endovascular balloon angioplasty should be attempted to a minimum of the contiguous uninvolved vein (Quinn et al 1995). Unfortunately, central vein stenosis tends to recur (Quinn et al 995, Kovalik et al 1994). The use of flexible stents has gained popularity recently despite the long term outcome is not well defined.

Fig. 2. Patient with a non-functioning left internal jugular vein hemodialysis catheter. Left subclavian venogram showed stenosis at proximal superior vena cava (arrow) with multiple collaterals in the neck (arrowheads).

#### **4.4 Fibrin sheath**

Fibrin sheaths account for 13-57% of catheter dysfunction (Suhocki et al 1996). The formation begins 24 hours after placement and it develops into a full-length sleeve after 5-7 days (Faintuch et al 2008). The sheath first occurs when fibrin adheres to the external surface before encasing the catheter and frequently extending the length of the catheter. The sheath seems to originate from the insertion site or the cuff and tends to migrate down the length of the catheter causing occlusion. Thrombi may also be trapped between sheath and catheter tip. A permcathogram done by injecting contrast through the catheter ports under fluoroscopic screening may show a persisting filling defect at the catheter tip or reflux of the contrast along the sheath in a retrograde direction (Figure 3). Fibrin sheaths may be treated by prolonged infusion of fibrinolytic agents (urokinase 30000 units/hour via each port x 4 hours or recombinant tissue plasminogen activator of 2.5 mg diluted in 50 ml normal saline

catheter over the working guidewire followed by a pigtail catheter insertion (Figure 2). The management of central stenosis is evolving. Whenever found, endovascular balloon angioplasty should be attempted to a minimum of the contiguous uninvolved vein (Quinn et al 1995). Unfortunately, central vein stenosis tends to recur (Quinn et al 995, Kovalik et al 1994). The use of flexible stents has gained popularity recently despite the long term

Fig. 2. Patient with a non-functioning left internal jugular vein hemodialysis catheter. Left subclavian venogram showed stenosis at proximal superior vena cava (arrow) with multiple

Fibrin sheaths account for 13-57% of catheter dysfunction (Suhocki et al 1996). The formation begins 24 hours after placement and it develops into a full-length sleeve after 5-7 days (Faintuch et al 2008). The sheath first occurs when fibrin adheres to the external surface before encasing the catheter and frequently extending the length of the catheter. The sheath seems to originate from the insertion site or the cuff and tends to migrate down the length of the catheter causing occlusion. Thrombi may also be trapped between sheath and catheter tip. A permcathogram done by injecting contrast through the catheter ports under fluoroscopic screening may show a persisting filling defect at the catheter tip or reflux of the contrast along the sheath in a retrograde direction (Figure 3). Fibrin sheaths may be treated by prolonged infusion of fibrinolytic agents (urokinase 30000 units/hour via each port x 4 hours or recombinant tissue plasminogen activator of 2.5 mg diluted in 50 ml normal saline

outcome is not well defined.

collaterals in the neck (arrowheads).

**4.4 Fibrin sheath** 

at a rate of 17 ml/hour through each port x 3 hours), mechanical stripping using a snare inserted via the femoral vein by exchange of catheter over a guidewire (Suhocki et al 1996, Faintuch et al 2008, Goldberg et al 1985). Diverse degree of success in fibrin sheath stripping is reported from different centers.

Fig. 3. (A) A fibrin sheath (arrow) formed inside the lumen of the CVC. (B) A permcathogram done showing a persisting filling defect (arrow) in the catheter lumen and reflux of the contrast at the catheter tip.

#### **4.5 Catheter-related bacteremia**

Catheter infection is a major cause of morbidity and mortality responsible for 6-28% of catheter failures (Bagui et al 2007). Diagnosis of catheter-related bacteremia (CRB) requires at least one of the following criteria: (a) clinical exit site infection with evidence of inflammation within 2 cm of sites; (b) definite organism grew from blood culture and catheter with no other apparent source of infection; (c) probable blood stream infection with defervescence after catheter removal when both blood and catheter tip infection is not confirmed in a symptomatic patients with no apparent source of infection; (d) possible blood stream infection in a symptomatic patients with defervescence after catheter removal, but remains culture negative.

The causative organisms are predominantly gram positive (~50%), gram negative bacilli (~25%) or polymicrobial (~20%). The most common occurrence is through the migration of skin organisms along the external surface of the catheter from the exit site wound or via the catheter lumen due to breakdown of aseptic technique. The organism can be embedded in a biofilm layer that confers protection from antibiotic therapy (Passerini et al 1992). Infection

Acute and Chronic Catheter in Hemodialysis 117

If the jugular veins are not accessible for long-term placement, the subclavian vein opposite the dominating side can be used. The nephrologist must realize the risk of subclavian stenosis (Feldman et al 1996, Can 2008). The subclavian vein should never be catheterized on

Fig. 4. Transhepatic placement of a Retrocath (45 cm long, 16Fr) into the portal vein. Contrast was injected to confirm the successful cannulation of the portal venous system.

translumbar catheter may also have the influenced outcome.

Other alternative sites have been used for CVC placement when none of the typical central accesses is available. Such procedures must be conducted by an experienced interventional radiologist in a fully equipped facility. Alternative methods may be used: catheterization of the inferior vena cava, or hepatic, translumbar, renal, intercostal and mediastinal veins. The translumbar approach to cannulation of the inferior vena cava, first described in 1971, has gained renewed attention as an alternative method for CVC access. High adequacy dialysis with low rates of catheter-related infection has recently reported from a single center study (Power et al 2009). The catheter care protocols, a policy of clinically appropriate catheter salvage with empirical broad-spectrum antibiotics and prior experience with

Transhepatic placement of hemodialysis catheter first described in 1994 can be associated with infrequent complications such as line sepsis, catheter migration, thrombosis and bleeding (Smith et al 204). These complications can be minimized when the procedure is performed by an interventional radiologist who is familiar with portal venogram (Figure 4)

**5. Other accesses for insertion of central venous catheter** 

the side of the unhealed arteriovenous fistula.

occurs when the organisms on the catheter exceed a certain quantitative threshold. Ninety percent of exit site infections respond to oral antibiotics without the necessity of catheter removal. Oral antibiotics can be used for minor infection but intravenous antibiotics should be administered if there is a discharge from the tunnel /exit site. If the infection fails to resolve with these measures, the catheter should be removed and replaced through a different track. Systemic sepsis or bacteremia carries a higher morbidity. K/DOQI guidelines recommend rapid removal of catheters in unstable patients with bacteremia or in stable patients if remain symptomatic 36 hours after achieving serum concentration of bactericidal antibiotics. In these cases, antibiotics should be administered for 14-21 days.


Rate of CRB (per 1000 catheter-days)

Table 6. Catheter locking solutions for prophylaxis against catheter-related bacteremia (CRB)

Prophylaxis of catheter-related bacteremia has been studied with standard antibiotics or antimicrobial agents such as taurolidine and 30% citrate as catheter locking solution. Seven randomized clinical trials documented substantial efficacy of antibiotic locks (gentamicin, minocycline or cefotaxime) in prophylaxis against catheter-related bacteremia (Dogra et al 2002, McIntyre et al 2004, Bleyer et al 2005, Kim et al 2006, Saxena et al 2006, Nori et al 2006, Filiopoulos et al 2011). An additional four studies documented reduction in frequency of catheter-related bacteremia using taurolidine or citrate as locking solution (Filiopoulos et al 2011, Allon 2003, Betjes et al 2004, Weijmer et al 2005). These studies are summarized in Table 6.

#### **4.6 Permanent vascular ingrowth**

Tissue ingrowth into the catheter lumen occurs when the tissue entraps the catheter onto the endothelial surface of the vessel. There is no standard management for this problem. Surgical approach of a thoracotomy is required as cut down on to the internal jugular vein for catheter is not usually possible.

occurs when the organisms on the catheter exceed a certain quantitative threshold. Ninety percent of exit site infections respond to oral antibiotics without the necessity of catheter removal. Oral antibiotics can be used for minor infection but intravenous antibiotics should be administered if there is a discharge from the tunnel /exit site. If the infection fails to resolve with these measures, the catheter should be removed and replaced through a different track. Systemic sepsis or bacteremia carries a higher morbidity. K/DOQI guidelines recommend rapid removal of catheters in unstable patients with bacteremia or in stable patients if remain symptomatic 36 hours after achieving serum concentration of bactericidal antibiotics. In these cases, antibiotics should be administered for 14-21 days.

Reference Type of locking solution Intervention Control

Dogra *et al.* 2002 Gentamicin 0.3 4.2 McIntyre *et al.* 2004 Gentamicin 0.3 4.0 Bleyer *et al.* 2005 Minocycline 0 0.472 Kim et al 2006 Gentamicin/Cefazolin 0.4 3.1 Saxena *et al.* 2006 Cefotaxime 1.7 3.6 Nori *et al.* 2006 Gentamicin 0 4.0 Minocycline 0.4 4.0 Filiopoulos *et al.* 2011 Gentamycin 2.7 9.9 Taurolidine/Citrate 3.7 9.9 Allon 2003 Taurolidine 0.6 5.6

<sup>2004</sup>Taurolidine 0 2.1 Weijmer *et al.* 2005 Citrate (30%) 1.1 4.1

 Rate of CRB (per 1000 catheter-days) Table 6. Catheter locking solutions for prophylaxis against catheter-related bacteremia

Prophylaxis of catheter-related bacteremia has been studied with standard antibiotics or antimicrobial agents such as taurolidine and 30% citrate as catheter locking solution. Seven randomized clinical trials documented substantial efficacy of antibiotic locks (gentamicin, minocycline or cefotaxime) in prophylaxis against catheter-related bacteremia (Dogra et al 2002, McIntyre et al 2004, Bleyer et al 2005, Kim et al 2006, Saxena et al 2006, Nori et al 2006, Filiopoulos et al 2011). An additional four studies documented reduction in frequency of catheter-related bacteremia using taurolidine or citrate as locking solution (Filiopoulos et al 2011, Allon 2003, Betjes et al 2004, Weijmer et al 2005). These studies are summarized in

Tissue ingrowth into the catheter lumen occurs when the tissue entraps the catheter onto the endothelial surface of the vessel. There is no standard management for this problem. Surgical approach of a thoracotomy is required as cut down on to the internal jugular vein

Betjes and van Agteren

(CRB)

Table 6.

**4.6 Permanent vascular ingrowth** 

for catheter is not usually possible.
