Central Line Management

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Continuing Education Activity

Central venous access is indicated in certain hospitalized patients. Common indications for central venous catheter placement include inadequate peripheral venous access, hemodynamic monitoring or recording of central venous pressures, peripherally incompatible infusions due to potency or irritation of administered medications, and implementing various therapies, including dialysis. However, central venous access is not without potential risks to the patient. Thus, institutional protocols must be followed properly to ensure successful and safe placement. Moreover, bundles are in place for routine management to prevent catheter-associated complications. The most common complications include infection, thrombosis, and other mechanical difficulties. This activity aims to illustrate how to manage central venous catheters safely and highlights the role of the interprofessional team in preventing catheter-associated complications.

Objectives:

  • Identify appropriate indications for central venous catheter insertion.
  • Select appropriate equipment and utilize proper antiseptic techniques to prevent infections of central lines.
  • Identify and manage the most common complications of central venous catheter placement and utilization.
  • Apply effective interprofessional team processes to improve care coordination and communication to reduce central venous catheter-associated morbidity.

Introduction

Central venous access is a procedure commonly performed for hospitalized patients with inherent risks. Central venous catheters are placed for various reasons, such as inadequate peripheral venous access, hemodynamic monitoring, infusion of peripherally incompatible infusions, and extracorporeal therapies.[1] The standard sterile placement and subsequent management of central venous access revolve around ultimately preventing catheter-based skin site or bloodstream infections, central line thrombosis, and mechanical complications.

Many studies have been conducted to determine the best strategies to incorporate in routine catheter maintenance, but institutional practices vary based on available resources.[2] However, the conceptual foundation for catheter maintenance is uniform and involves aseptic techniques when handling or manipulating catheters and routine evaluation of catheter necessity. These concepts are commonly implemented as intervention packages, more commonly known as bundles, which involve mandatory checklists for the safe insertion of central venous catheters and catheter maintenance and frequent educational opportunities to ensure the standard of care is emphasized and achieved.[3][4][5]

Anatomy and Physiology

The basis of site selection for central venous access is determined by the patient’s anatomy, clinical factors, and procedure indication. Central venous access can be achieved via the internal jugular, subclavian, or femoral veins.[6] Though any location can be viable, current evidence recommends a subclavian approach; this site has the lowest risk of infectious complications.[7] Prior studies revealed the highest risk of catheter-related infections when access is obtained via the femoral vein compared to other locations.[8][9]

Indications

Peripheral venous access is the best choice when there is a short-term need for access, adequate peripheral sites, and the patient does not have specific indications for central venous access. Indications for central venous access include infusates incompatible with peripheral administration, a need for invasive hemodynamic monitoring, multiple infusions or infusion incompatibility, and parenteral nutrition.[10] However, the complications of central venous access increase hospital-related costs and patient mortality.[11] Frequent review of the central venous access bundles is encouraged to minimize complications. Routine care of the central venous catheter should occur whenever the catheter is manipulated, accessed, or used.

Contraindications

There are few relative contraindications to standard central venous catheter insertion.

Bleeding postinsertion is uncommon; moderate-to-severe coagulopathy before initial catheter placement is a relative contraindication to the procedure. If possible, correction of the underlying coagulopathy or thrombocytopenia should occur before insertion; this sometimes is not a viable option in an unstable patient.

Other relative contraindications to central venous catheterization include site-specific considerations. Avoidance of insertion sites with known indwelling intravascular hardware, such as permanent hemodialysis catheters or pacemaker leads, is recommended.

After catheter insertion, there is no contraindication to routine catheter maintenance and care. In the event of insertion site infection, decreased functionality, or new bacteremia, the catheter ideally should be removed. However, if there is a need to maintain critical venous access to maintain hemodynamic or clinical stability, the line should be utilized until another working site is available.[12] Additionally, catheters need not be removed in all settings, such as in catheter-related thrombosis.[13]

Equipment

Sterile Insertion Practices

  • Performance of good hand hygiene 
  • Aseptic technique
  • Maximal sterile barrier (hairnet, mask, gown, sterile gloves, full body drape)
  • Preparation of the intended insertion site with chlorhexidine
  • Securing the catheter with a suture or clamp
  • Placement of a sterile dressing over the insertion site 

Routine Manipulation of the Central Line

  • Cleaning with alcohol or chlorohexidine swabs
  • Use of nonsterile nitrile gloves
  • Soap and water or alcohol hand scrub
  • Catheter hub locks

Sterile Dressing Change Requirements

  • Hairnet
  • Face mask
  • Size-appropriate sterile gloves
  • Chlorohexidine preparation
  • Sterile gauze
  • Biopatch or chlorhexidine-containing dressings 
  • Transparent, sterile dressing

Personnel

A skilled clinician usually performs central venous catheter placement. Management of the central venous catheter is typically performed by skilled nursing or medical staff. Patients, such as those receiving home-based antibiotic infusions, should not be manipulating or using the access site without adequate training in its use and care.

Preparation

Healthcare workers' hands may be contaminated with organisms from the hospital environment; therefore, hand hygiene remains important in reducing nosocomial and catheter-based infections.[14][15][14] 

Standard insertion practices for central venous catheter placement have been developed.[16] Catheter dressing changes should be executed using a sterile technique.[3][8][17][18][19]

Technique or Treatment

During initial central venous catheter placement, using soap and water or alcohol-based scrubs should be standard practice before donning sterile gloves. Double gloving is encouraged with a colored indicator glove underneath to identify any glove perforations.[20] Using sterile drapes, gowns, gloves, and precautions will help minimize catheter contamination during insertion.  

Skin preparation with both mechanical and chemical preparation using 0.5% chlorhexidine is preferable to povidone-iodine or 70% alcohol unless the patient has an allergy to chlorhexidine. Skin preparation decreases the skin flora and reduces catheter-based infections. After completion of the procedure, a sterile dressing should be applied over the insertion site before using the catheter.[8][17][18][14] 

After insertion, any manipulation or use of the catheter should occur only when clinically indicated. Routine daily inspection of the central line should be performed. A daily inspection should evaluate the proper position and functionality of the line and for signs of infection, including erythema and drainage. Dressing changes should occur every five to seven days with a transparent dressing or every two days if a gauze dressing is used. However, the dressing should be changed sooner if it is no longer adherent, its integrity is compromised, or it becomes visibly soiled. Studies revealed no difference in the rate of catheter-related bloodstream infections when chlorhexidine-impregnated dressings were used compared to other dressings, such as adhesive Tegaderm HP Transparent Film Dressing 3M, sterile gauze, and micropore tape, among others.[11] However, there is limited data to support the use of silver-impregnated dressings in non-dialysis catheters.[21]

Once the dressing is removed, the catheter insertion site should be cleaned to prevent bacterial transmigration. Sterile technique should be used at all times when handling central catheters. A chlorohexidine solution is recommended to sterilize the area surrounding the catheter site. Once the area is dry, a sterile dressing should be reapplied and remain in place per institutional protocol or until the catheter is removed.[14] Prolonged use of adherent dressings can lead to allergic contact dermatitis and other skin-related injuries from repeated removals and applications. Early identification of skin irritation and injury will allow the team to make necessary adjustments to prevent future occurrences.[22]

Catheter connections also require sterile precautions. In addition to hand hygiene, the healthcare worker should diligently disinfect the injection ports, needleless connectors, and catheter hubs with either 70% alcohol or chlorhexidine swabs before use. Recommendations also include changing the intravenous administration set every 96 hours. If intravenous administration sets are used to infuse lipid-containing solutions and medications like total parenteral nutrition (TPN) or propofol, the sets should be exchanged every 24 hours. The intravenous set should also be changed every 24 hours if used to infuse blood products. When a catheter hub is not used, catheter locks should be applied.[23][24]  

As previously mentioned, proper insertion and maintenance technique prevents complications. Thus, many institutions implement central venous catheter bundles, highlighting five critical concepts: hand hygiene, maximal sterile barrier precautions during insertion, cleaning the skin with chlorhexidine preparation, avoidance of the femoral insertion site if possible, and removal of any unnecessary catheters.[25] Despite these recommendations, resources may be scarce, which can contribute to institutional compliance and the variability of infection rates.[16][2]

Complications

Complications can occur during and after central venous catheter placement. The risk of complications is increased when central venous catheters are placed without ultrasound guidance, including an increased number of performed attempts and a higher chance for incidental placement into an artery or surrounding structures.[26] An inadvertent arterial puncture can lead to the formation of a hematoma or pseudoaneurysm, which can compress surrounding structures, undergo dissection, and promote the creation of an arteriovenous fistula.[27] Arrhythmias can occur during central venous catheterization from the catheter or guidewire entering the heart or from incorrect placement.[28]

After catheter placement, the most frequent complication is infection. Infection should be considered in patients with an indwelling catheter who have fevers, erythema at the insertion site, new-onset swelling, purulent drainage, leukocytosis, or hemodynamic instability. A thorough workup should be initiated with the catheter as a potential etiology, and removal of the catheter should be strongly considered.

Other common complications include catheter occlusion.[8] Potential causes of catheter occlusion include catheter malposition or migration, thrombotic occlusion, drug precipitation, or mechanical occlusion. Therefore, the catheter should be inspected.

Catheter thrombosis can contribute to morbidity and mortality if not addressed appropriately. A majority of catheter-related thrombosis occurs within the upper extremities.[29] A thrombus can be a potential source of infection, or it may propagate. Not all patients with catheter-related thrombosis exhibit symptoms. Routine catheter removal in catheter thrombosis is not typically recommended; treatment consists of anticoagulation therapy.[30] Catheter thrombosis can occur secondarily from a fibrin sheath formed on the external catheter wall or an intramural thrombus shortly after insertion. Additional risk factors for catheter thrombosis include previous vessel catheterization, poor catheter positioning, specific catheter diameters, improper catheter care, type of infusate, or underlying malignancy. 

Mechanical occlusion of the catheter can occur if there is any kinking or clamping in the catheter tubing at any location or external compression from a suture or other sources. However, thrombolytic agents, such as alteplase, can be used if there is still a concern for thrombosis after troubleshooting the nonfunctional catheter with other methods and ruling out additional causes. Frequent catheter flushing with either heparin or normal saline can prevent or minimize thrombosis in certain situations. Studies have shown a minimal difference in the efficacy of intermittent locking with either normal saline or heparin.[30][31] The intravenous devices should be flushed with normal saline before and after medication administration.[32]

Clinical Significance

Routine central venous catheter management aims to reduce catheter-based infection, the most common complication. Other complications, such as abscess, cellulitis, and bacteremia, can lead to poor patient outcomes, increased use of antibiotics, and increased hospital length of stay and costs.[33] Even though routine maintenance is paramount in preventing complications, deciding to keep a central line is equally important. Catheters should be removed if there is a concern for sepsis or persistent bacteremia despite more than 72 hours of proper antimicrobial therapy.[34]

Enhancing Healthcare Team Outcomes

Central venous access maintenance and troubleshooting are crucial and necessary skills for all healthcare workers. These practices should be performed routinely to decrease or prevent catheter-based infections and complications. While initial access is typically obtained by trained physicians, physician assistants, and nurse practitioners in the standard sterile fashion, nursing staff in intensive care units or general wards will primarily perform routine care and management. Every healthcare team member is responsible for evaluating the ongoing need for central venous access and ensuring prompt removal when no longer necessary. Routine evaluation by every team member will ensure that appropriate handling and care of the central catheter is being performed to help reduce the risk of catheter-associated complications. Multidisciplinary team training is indicated to ensure the success of the bundles. Frequent bundle monitoring and overview are also required to identify gaps and provide feedback to improve the quality of patient care.[5][25]


Details

Editor:

Peter P. Lopez

Updated:

5/26/2023 11:29:00 PM

References


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