Most hospitalized patients have placement of a peripheral venous access device, either a short peripheral catheter or a peripherally inserted central catheter. Compared with central venous catheters that are not peripherally inserted, the other 2 types are generally perceived by health care providers as safer and less complicated to manage, and less emphasis is placed on the prevention and management of complications. Expertise of nurses in inserting, managing, and removing these devices may reduce the likelihood of complications, and increased recognition of complications associated with use of the devices is important to ensure continued improvements in the safety, quality, and efficiency of health care. Complications associated with short peripheral catheters and peripherally inserted central catheters include tourniquet retention, tubing and catheter misconnections, phlebitis, air embolism, device fragment embolization, and inadvertent discharge with a retained peripheral venous access device. Integration of prevention, detection, and recovery strategies into personal nursing practice promotes the quality and safety of health care delivery.
Use of venous access devices (VADs) is ubiquitous in health care. Experts estimate that at least 85% of patients hospitalized in the United States receive intravenous therapy.1–3 Most hospitalized patients have insertion of a peripheral VAD (PVAD), either a short peripheral catheter (SPC) or, less commonly, a peripherally inserted central catheter (PICC). Compared with non-PICC central venous catheters (CVCs), SPCs and PICCs are generally perceived as safer and easier to manage,4 and less emphasis is placed on the prevention and management of complications.5,6 The expertise of nurses who insert, manage, and remove these devices may affect the likelihood of complications,1 and increased recognition of PVAD complications is important to ensure continued improvements in the safety, quality, and efficiency of health care.4,7,8
In this article, I focus on strategies for prevention, detection, and recovery for selected complications of SPCs and PICCs relevant to acute and critical care nurses. The emphasis is on strategies most easily integrated into personal nursing practice. Complications reviewed include tourniquet retention, tubing and catheter misconnections, phlebitis, air embolism, embolization of device fragments, and inadvertent discharge of patients before removal of a PVAD. Table 1 provides basic definitions and signs and symptoms of these complications.9–18
Several important PVAD complications are not reviewed: catheter-associated venous thrombosis, infiltration and extravasation, and infection; these are briefly described in Table 1. Guidance in addressing prevention and management of PICC-related infection and thrombosis4,19–23 and PVAD infiltration and extravasation3,24–26 is widely available. A review is provided in the sidebar Bloodstream Infection Associated With Short Peripheral Catheters.
Bloodstream Infection Associated With Short Peripheral Catheters
Monitoring for catheter-associated bloodstream infection, system-level prevention efforts, and research and published guidelines overwhelmingly focus on central venous access devices.5,6 However, as Hadaway5 notes, the Centers for Medicare and Medicaid Services disallows payment for any “vascular catheter-associated infections,” including infections associated with short peripheral catheters (SPCs), both local and systemic.
The incidence of local soft tissue infection related to SPC placement is not well defined,27 and discussions about SPC-associated infection are complicated by overlapping and conflicting definitions of phlebitis and local soft tissue infection. SPC-associated bloodstream infection is rare: 0.1% of SPCs placed, or 0.5 per 1000 catheter days.28 By comparison, the rate of bloodstream infection associated with peripherally inserted central catheters among hospitalized patients is estimated to be 6%, or 2.16 per 1000 catheter days (similar to the reported rates for central venous catheters).29
Bloodstream infection associated with an SPC is a potentially life-threatening complication. In one case,30 a patient died after an SPC inserted in the emergency department “went unnoticed for 5 days.” Phlebitis and infection developed, directly resulting in the patient’s death. In another case,2 a patient had a well-functioning SPC that had been placed 96 hours earlier. He had no signs or symptoms of inflammation. Discharge was (at that time) anticipated for the next day, and placement of a new SPC was likely to be difficult, so the interdisciplinary team opted to keep the first SPC in place. During the next 24 to 48 hours, the site became erythemic. The SPC was promptly removed, but bacteremia due to methicillin-resistant Staphylococcus aureus developed followed by an epidural abscess that required 6 weeks of intravenous antibiotics. The infections were directly attributed to phlebitis at the SPC site.
Nurses should be aware that, although uncommon, SPC-associated bloodstream infection can occur. Although the connection between local inflammation and infection is poorly understood, early recognition of phlebitis, prompt removal of the related device, and ongoing monitoring of the inflamed access site after removal of the device may reduce the harm of SPC-associated bloodstream infections. These infections are preventable; selection of the optimal device and site for insertion; proper site preparation and insertion; and use, management, and removal of SPCs (evaluated and reinforced through ongoing competency verification) reduce the incidence of these serious events.31
Peripheral VADs
Short Peripheral Catheters
Peripherally Inserted Central Catheters
PICCs are venous catheters 30 to 40 cm long that are inserted in an upper extremity and terminate in the vena cava.3 Compared with SPCs, PICCs permit prolonged duration of therapy, allow central infusion of vesicants and irritants, and (when fully operational) reduce the need for repeated phlebotomy. According to market research cited by the Agency for Healthcare Research and Quality,33 more than 2.5 million PICCs were inserted in acute care settings in the United States in 2010. The popularity of PICCs is due to multiple factors, including implementation of nurse-led insertion teams, improved patient satisfaction, and the perception that PICCs are safer than are non-PICCs.4,34,35 Experts report that PICC use has steadily increased since the early 2000s.29,36
PVAD Complications: General Considerations
Recognition of complications of SPC and PICC use is important for many reasons. The sheer pervasiveness of use of PVADs demands attention to prevention of complications and reduction of harm. Unfortunately, many experts4,8,16,33 suspect that PVAD complications are underrecognized among health care providers, partly because of persistent overestimation of the safety of these devices.
SPCs and PICCs have unique characteristics: the complication profile, prevention, detection, and recovery strategies differ between SPCs and PICCs. Whenever possible, I have covered the specific considerations for PICC versus SPC management. When information about complications associated with a specific device is limited (eg, PICC-related tourniquet retention and embolization of fragments of an SPC device), I have noted the deficiencies.
The Infusion Nurses Society describes multiple factors contributing to the general risk for SPC complications, including lack of standardization of technique, variations in practice, communication breakdowns, and insufficient knowledge and skills among providers. These factors contribute to inappropriate selection of site or device or both and suboptimal device placement, use, management, and removal, situations that ultimately may lead to complications. These factors certainly also contribute to PICC-related complications.
Selection of an appropriate device and insertion site is the first critical step in minimizing PVAD complications and harm. The patient’s condition, as well as the anticipated duration and type of intravenous therapy, are considered during selection of the device and site.3 The Infusion Nurses Society3 provides practice criteria for site selection; however (with the exception of the recommendation to avoid insertion of SPCs in lower extremities), evidence supporting the criteria is of low quality (ie, recommendations from professional organizations or a generally accepted standard of practice without a research basis). PICCs are indicated for short- or long-term infusion of vesicants and known irritants3 ; the convenience of the patient or the provider is not an appropriate indication for PICC placement.37 Selection of an infusion device should include an evaluation of the risks and benefits of specific devices as indicated by available evidence. For example, PICCs and CVCs are associated with similar rates of infection4,29,36 and with a high risk for deep vein thrombosis.4,23
Health care providers underrecognize the complications of SPCs and PICCs, partly because they overestimate the safety of these devices.
PVAD complications can interrupt or delay critical treatments; provoke pain and discomfort; reduce patient satisfaction; and result in suboptimal health care outcomes, injury, permanent disability, and death.3 Complications may also necessitate more invasive and costly vascular access or require additional patient monitoring and therapies, contributing to additional avoidable costs in health care.
Tourniquet Retention
Cases of tourniquets left applied to extremities after attempts at SPC placement (referred to as tourniquet retention) are described in articles on patient safety.9,38 Properly applied, a tourniquet generates distal venous distention, promoting successful SPC (or PICC) placement. Unfortunately, a tourniquet may be inadvertently left in place for many hours after an attempt (successful or otherwise) to secure intravenous access9,38 or after phlebotomy. The true incidence of these events (and resultant injury) is unknown. In the only published review9 of these events, Pennsylvania health care facilities reported 125 retained tourniquets related to either phlebotomy or “IV line” placement to the Pennsylvania Patient Safety Authority (PA-PSRS) in a single year.9
Tourniquet retention can result in infiltration, extravasation, nerve damage, compartment syndrome, and thrombosis.9 Serious harm is thought to be rare: of 125 events reviewed by PA-PSRS, only 2 caused serious harm (as defined by PA-PSRS), specifically a transfer to a higher level of care and a marked infiltration.9 Although tourniquet retention associated with PICC placement has not been specifically described, the same factors that contribute to SPC-related tourniquet retention apply to PICCs (Table 2).
A key prevention strategy that can be integrated into practice is consciously and completely releasing tourniquets when any interruption occurs in the task that requires use of a tourniquet.9,38 Even seemingly inconsequential interruptions (eg, leaving the bedside to retrieve an item just across the room) should be considered moments of potential risk for a tourniquet retention.
Recovery and reduction of the potential for harm depends on prompt discovery of a retained tourniquet. Retained tourniquets are rarely discovered by the person who applied the tourniquet (ie, in < 1% of analyzed reports).9,38 Signs and symptoms may be subtle and nonspecific (Table 1), and patients most at risk for tourniquet retention may lack the ability to communicate their symptoms reliably. Thorough patient assessment, including inspection of all vascular access sites and distal extremities, theoretically improves the ability to detect a retained tourniquet and reduce the potential for harm.
Tubing and Catheter Misconnections
Tubing and catheter misconnections occur when components of one medical device are attached to the connector or port of another medical device that is used for a fundamentally different function (eg, attachment of enteral feeding tube to a PICC).39 Misconnections occur with all types of VADs. The risk for misconnections involving PVADs is high, because of the devices’ prevalence of use.40 Inadvertent intravenous administration of a variety of liquids and gases (including enteral feedings, breast milk, medical gas, and air) has been reported.10–12,39–41 Although described as occurring with “significant frequency,”10 these events are underreported and the true incidence is unknown.40
Signs and symptoms of infusion of an unintended fluid or gas vary widely; those listed in Table 1 are aggregated from published case reports. Clinical manifestations are related to many factors, including the patient’s size and health status and characteristics of the material infused (eg, volume, infusion rate, pH). Although some patients recover from misconnections, these events can result in permanent injury (eg, permanent neurological deficits, organ failure) or death or both.10–15,39,41
The underlying cause of many misconnections is device overcompatibility. The ability to connect components of infusion systems (eg, PICC hubs, intravenous tubing) to sequential compression devices, enteral feeding sets, and blood pressure cuff tubing (among other devices) is an intrinsic risk.10,11 If connection is physically possible, inevitably the connection will occur, even when such an error seems unlikely or implausible.10,11
Detection of misconnections is impeded because clinicians underappreciate the risk and may not consider misconnection as a cause of clinical changes and because the patient’s signs and symptoms may mimic those of more commonly suspected conditions (eg, pulmonary embolism). A selection of strategies for prevention, detection, and recovery for misconnections is outlined in Table 3.
On the basis of the principle that device overcompatibility contributes to misconnection events, the International Organization of Standardization has developed new standards for medical device connections. The standards, which should be fully implemented by 2017, will result in products that are less compatible (or wholly incompatible) with functionally dissimilar devices. The anticipated result will be reduced (but not wholly eradicated) risk for misconnection events.12 Awareness of risk, prevention, detection, and recovery strategies will remain essential.
Phlebitis
Phlebitis occurs when chemical, mechanical, or particulate-induced irritation promotes local inflammation of the vein wall.5 Phlebitis is a common complication of SPC use and a known complication of PICC use. After development of marked phlebitis, increasingly invasive strategies may be necessary to maintain vascular access (eg, central catheter placement), culminating in increased cost, decreased patient satisfaction, or delay in therapy.42
Short Peripheral Catheters
Phlebitis is the most common complication of SPC use, occurring in 7% to 75% of patients with SPCs.1–3,27,32,43 Reported rates of SPC-associated phlebitis vary widely among different populations of patients and are often not comparable because of variations in the definition of phlebitis.2,3,6 Phlebitis may develop up to 48 hours after an SPC is removed.3
Peripherally Inserted Central Catheters
Phlebitis also occurs with PICCs, most commonly when the devices are inserted in the antecubital fossa.17 Although PICC-associated phlebitis associated with chemical irritants is described as rare because of the dilution of the infused material that occurs as a benefit of PICC use, 2 mechanisms resulting in altered flow during infusion have been described: catheter damage and development of a fibrin sheath.17 Catheter damage (eg, fracture of the catheter) permits the infused material to infiltrate into tissue more peripherally than intended, where the material can induce local irritation. Alternatively, a fibrin sheath can develop around the PICC, partially occluding or disrupting flow at the tip. Depending on the characteristics of the sheath, the infused material might be directed backward toward the insertion site, resulting in local irritation where the material exits the sheath.17
Special Considerations in Detection, Prevention, and Recovery
The Centers for Disease Control and Prevention and other authorities recommend routine replacement of SPCs every 72 to 96 hours; however, many experts claim that the evidence for routine replacement is suboptimal.2,27,44 Fang2 recommends placing emphasis on prevention of SPC phlebitis by ensuring skill and competency with respect to device placement, use, and routine maintenance rather than by focusing on scheduled SPC replacement. Routine use of in-line filters with SPC infusions has been suggested as a strategy to reduce phlebitis by reducing particulate-induced irritation; however, a 2010 systematic review42 of randomized controlled trials indicated that the evidence for the benefit associated with use of in-line filters is “uncertain.” To prevent phlebitis, nurses should adhere to local facility guidelines about SPC replacement (and use of in-line filters) and promote evaluation of evidence on PVAD management and implementation of evidence-based policy and procedure.
Table 4 describes selected risk factors for the development of phlebitis and key strategies for prevention, detection, and recovery. Discovery of phlebitis necessitates prompt removal of the PVAD and initiation of new access, if clinically indicated. Thrombus or infection may develop in conjunction with phlebitis,2 although the direct pathophysiological relationship between phlebitis and subsequent infection is poorly understood.5,6
Air Embolism
Air embolism is commonly associated with CVC placement or removal but also occurs with the insertion, use, and removal of PICCs and SPCs.16,45 Air embolism is uncommon (the true incidence is poorly defined)41 but highly lethal, with a mortality greater than 30%.46,47 The Centers for Medicare and Medicaid Services consider device-associated air embolism a preventable, nonreimbursable serious reportable (or “never”) event.48
The clinical manifestations of air embolism vary widely according to patient characteristics (eg, body size, underlying health status, and presence of a patent foramen ovale), the rate of the infusion, the volume of air infused, and the ultimate anatomical location of the embolism. The likelihood of major injury or death is related to many of the same characteristics.49
Inadvertent administration of small, generally inconsequential, volumes of air occur regularly during PVAD placement,49 but no safe volume of venously administered air has been described. Fatal volume of air in humans is generally accepted as 50 mL (or 3–5 mL/kg), but up to 20 mL in adults can be lethal if delivered rapidly.49 The lungs can filter up to 0.35 mL/kg of air per minute, but higher volumes or the presence of a patent foramen ovale (occurring, often asymptomatically, in 10%–35% of adults and in neonates)16,49 permits air to enter the systemic arteries and travel to end organs where it can induce ischemia, infarction, or a thromboinflammatory response. Because of the risk, intravenous infusion of any volume of air should be considered “potentially consequential”49 and should be judiciously avoided.16,49
Phlebitis, which occurs with both SPCs and PICCs, can develop up to 48 hours after a device is removed.
In a detailed review of infusion-related air embolism, Cook16 reports challenges associated with recognition and treatment of this complication. Specifically, clinicians may not readily recognize the reason for air entry, the diagnosis may not be intuitive, and even if air embolism is suspected, immediate interventions may seem ineffective. Furthermore, the signs and symptoms of air embolism are nonspecific and mimic many other conditions (Table 1). Prompt recognition and immediate response are critical to reduce harm associated with air embolism.50 Table 5 outlines specific actions to initiate in response to suspected air embolism. Providers’ awareness of specific clinical scenarios that may trigger an air embolism may potentially improve the likelihood of recognition of this complication and prompt action.16 Several scenarios relevant to acute and critical care settings are described in the sidebar Clinical Scenarios Resulting in Air Embolism.
Device Fragment Embolization
Device fragment embolization (DFE), also known as catheter embolism, is a rare complication of use of all types of VADs. When a device fragments, pieces may lodge in the peripheral venous system, right ventricle, or pulmonary vasculature.18
Clinical Scenarios Resulting in Air Embolism
Air embolism associated with peripheral vascular access devices (PVADs) is a rare but potentially deadly complication. Prompt recognition and immediate action can reduce the likelihood of patient harm; however, providers may not detect an air embolism because of to the nonspecific signs and symptoms and an underappreciation of the clinical scenarios that may lead to this potentially life-threatening complication.16 Clinical scenarios relevant to acute and critical care settings include the following:
Inadvertent intravenous administration of an air bolus, often delivered through an air-containing syringe or unprimed infusion tubing, is the most common mechanism for air embolism.16,49 Both of these sources may result in an embolism large enough to cause cerebral ischemia and infarction.
Infusion of air (and other medical gases) has been reported in instances in which oxygen (or air) tubing or an air-filled enteral syringe is inadvertently attached to a VAD.10,11,16,39–41 Misconnection events are discussed in the text.
Compared with short peripheral catheters, peripherally inserted central catheters (PICCs) are particularly susceptible to external hub and catheter fracture.16 PICC barotrauma can be caused by excessive pressure generated by use of syringes smaller than 10 mL, by use of an unsanctioned power injector, or by flushing a PICC against resistance.17 Twisting, kinking, cutting, or clamping of catheters and hubs can result in mechanical damage. The age of a device and storage conditions can also contribute to potential for fracture. In one case, 2 consecutively placed PICCs fractured shortly after placement. The devices, although not past the expiration date for use, were “hard and brittle.” Investigation revealed that the PICCs had been exposed to ultraviolet light while in storage and had degraded before use.51
Infusion of small bubbles may occur during continuous intravenous administration.16,49 Infusion devices are designed to permit no more than 1 mL of air during a 15-minute period, but according to the Food and Drug Administration,51 this standard “does not represent a universally safe level of air infusion,” and the clinical impact of cumulative infusions of small air bubbles is poorly defined. When entrained air is visually noticeable, continued infusion of air should be prevented, regardless of the presence or absence of alarms from the infusion device. Of note, patient positioning and attempts to aspirate the air do not ameliorate the consequences of air embolism related to the entrainment of particularly small (micro) bubbles.47
Although occurrence of an air embolism during or after VAD removal is most commonly associated with central venous catheters, embolism can also occur in association with removal of PVADs.16 PICCs and large-bore short peripheral catheters inserted above the heart (eg, in the external jugular vein) provide adequate ingress for a clinically significant amount of air; and the standard techniques for removal of a central venous catheter should be used for these devices. Two primary mechanisms for air embolism related to removal of VADs are improper removal technique (eg, not placing the patient in the Trendelenburg position) and not placing (and maintaining) a truly occlusive dressing on the access site after the device is removed. After a catheter is removed, a tract providing a pathway for air can persist for up to 24 hours. This tract may provide ingress of air in response to the pressure gradient caused (or exacerbated) by reduced intrathoracic pressure (inhalation) or hypovolemia. Occluding the catheter tract during catheter removal and for at least 24 hours afterward and using appropriate dressing materials can markedly reduce the likelihood of an air embolism after device removal. Removal of central venous catheters (including PICCs) and similar devices (eg, short peripheral catheters placed in the external jugular vein) is a procedure with potential for serious complications, and providers should have appropriate training and ongoing verification of competency in removal.17
Short Peripheral Catheters
Peripherally Inserted Central Catheters
DFE is a well-documented complication of PICC use.17,18 A retrospective review18 of 215 central catheter DFEs in adults reported during a 20-year period indicated that at least 30 of the embolizations involved PICCs. Multiple mechanisms exist whereby a PICC fragment can develop and embolize (Table 6). DFE can be due to improper technique in placing a PICC, improper use of the device (eg, improper flushing resulting in barotrauma), removal, or catheter exchange.3,17,18 Overall mortality due to embolization of fragments of central VADs, including PICCs is thought to be less than 2%.18
Special Considerations in Detection, Prevention, and Recovery
The clinical manifestations after DFE vary widely,3 and most literature addresses the signs and symptoms related to DFE of central catheters. Catheter dysfunction (eg, inability to aspirate blood or flush the device, pain or swelling during use, leakage at the insertion site) may be a precursor to DFE3 or may be the first sign of DFE18 and should be fully investigated. Once DFE occurs, patients may experience arrhythmias or may report palpitations (the most common indication).17 Other signs and symptoms are listed in Table 1. DFE can also be asymptomatic, and the presence of a foreign body may be found only incidentally (eg, during routine chest radiography) months to years after the embolization.18
Table 6 lists selected prevention, detection, and recovery strategies for DFE. Removal of a PICC against resistance constitutes one preventable cause of PICC embolization.17 Transient vasospasm creates the resistance, and continued attempts to remove the catheter can result in fracture of the device. If a provider encounters tension while attempting removal, the (external) retrieved part of the PICC should be coiled under a sterile dressing, and cautious reattempts to remove the device can be made after the vasospasm has resolved. After removal of a VAD, regardless of whether or not resistance was encountered, the integrity of the device should be assessed. For all CVADs, the catheter length should be measured and compared with the documented insertion length to improve the likelihood of detection of catheter fragmentation.17
Unintentional Discharge With a Retained PVAD
Although the incidence of inadvertent discharge of a patient from a health care setting who has a PVAD remaining in situ is unknown, events involving SPCs have been reported,54,55 and no reason suggests that PICC-related events have not occurred. An inadvertently retained PVAD may increase a patient’s risk for phlebitis, bleeding, thrombosis, or infection. Patients who discover a retained PVAD may experience distress, anxiety, reduced satisfaction, distrust in health care, and additional expenses (eg, if asked to return to a health care setting for removal of the device).
Conceivable scenarios in which a PVAD is retained include patients who leave before final assessment by a nurse, patients who unintentionally conceal the PVAD during final review before discharge (eg, under clothing), and patients and/or members of the clinical team who forget that a PVAD is still in place. In other instances, patients may deliberately depart with an intravenous catheter in place. Instances that involve willful deception or concealment by patients are difficult to prevent, and I do not address them. In addition, few researchers have investigated these types of events and strategies for prevention.
No guidelines exist for management of a retained PVAD discovered after discharge, presenting an opportunity for development of checklists or standard procedures for treatment. Organizational-level contributing factors can potentially be identified and addressed through review of cases of retained PVADs. For example, hypothetically, emphasis on timely and early (morning) discharge, insistence on maintaining intravenous access for admitted patients regardless of clinical indication, and increased handovers and handoffs may contribute to the likelihood of inadvertent discharge of a patient with a retained PVAD. Proposed practice- and unit-level (or organizational-level) strategies for prevention, detection, and recovery of retained PVADs are given in Table 7; however, retained PVADs remain an area for continued nursing research and practice development.48
Nursing Implications
PVADs are omnipresent in health care, yet many complications of their use are underrecognized. Nurses in acute and critical care environments, as well as nurses who are members of teams that manage intravenous devices, should strive to enhance recognition of PVAD complications, risk factors for complications, and strategies for prevention, detection, and recovery. Key elements of prevention of these complications include reevaluating basic knowledge and skills related to insertion, management, use (including device stabilization), and removal of PVADs.7,8 Nurses with expertise and experience in PVAD management have the opportunity to lead (or consult on) development of device-related competencies and strategies to improve device-related safety and quality. In addition, nurses with enhanced awareness of device-related hazards are critical members of product acquisition and review teams, evidence-based practice committees, and work groups focused on patient safety, quality improvement, and system design or redesign.
Although use of PVADs is extremely common, gaps remain in the overall understanding and evidence-based guidance concerning these devices. Additional research is warranted in multiple areas of PVAD safety, including the following:
Ensuring ongoing competency and expertise in the selection, insertion, management, and removal of the variety of VADs available in acute and critical care
Investigating routine replacement of SPCs and their impact on phlebitis, thrombosis, infection, and health care costs
Understanding the consequences and circumstances associated with inadvertent discharge of a patient with a PVAD in place
Investigating local and bloodstream infections related to SPCs, including incidence and prevention strategies
Ultimately, nurses play a vital role in the optimal insertion, management, use, and removal of PVADs. Understanding related complications and their risk factors, combined with integration of prevention, detection, and recovery strategies into practice, promotes quality and safety of health care delivery.
References
Footnotes
To purchase electronic or print reprints, contact the American Association of Critical-Care Nurses, 101 Columbia, Aliso Viejo, CA 92656. Phone, (800) 899-1712 or (949) 362-2050 (ext 532); fax, (949) 362-2049; e-mail, [email protected].
Financial Disclosures
None reported.
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