Chapter 5. Layer Interventions

Preventing Hospital-Acquired Venous Thromboembolism

A systematic effort to improve venous thromboembolism (VTE) prophylaxis prevalence starts with a single, specific intervention: the VTE protocol. The team should consider the VTE protocol the prerequisite, enabling layer for any subsequent interventions. An example of a VTE protocol appears at Appendix B. Once the VTE protocol is in place, the team can layer additional interventions (e.g., education and performance audits and feedback) to leverage it. 

The Venous Thromboembolism Protocol

The team may come up with a dozen interventions to optimize prevalence of appropriate VTE prophylaxis. One intervention every team should implement first is a very well-integrated VTE protocol. Go to Chapter 2 for an overview of the components of a VTE protocol.

For selected inpatients, such as those with major orthopedic procedures, there are high-level recommendations from the American College of Chest Physicians to extend VTE prophylaxis beyond the duration of the hospital stay. The evidence base may eventually identify other populations that may benefit from extended prophylaxis. The team should address this issue and incorporate guidance on extended duration of VTE prophylaxis into the discharge process.

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Key Principles for Effective Quality Improvement Interventions

A VTE protocol and any subsequent layers of quality improvement (QI) interventions will usually fail unless the team pays attention to details. Principles for effective interventions follow.

Principle 1. Keep it simple for the end user.

Inevitably there will be tradeoffs between the depth of detail to give providers and the simplicity of the forms and processes they are asked to accept. Almost always, simpler is better. Minimize calculations the end user has to make or automate that process for them. For a VTE protocol, limit prophylaxis options to as few as possible for each VTE risk category.

Principle 2. Do not interrupt workflow.

The caregiving team will have multiple demands competing for attention and time. In general, if an intervention interrupts workflow, it will be rejected. Involve frontline workers to make sure the VTE protocol is easy to use. Without their input, implementation will not go smoothly. Focus-group feedback is invaluable and easy to obtain.

Clinicians will want to use the order sets if they are designed properly. When designing the form, consider the fact that checkbox orders are easier to use than free text and can encourage acceptance of a new form.

If the team cannot incorporate a VTE risk assessment within admission, postoperative, or transfer order sets, a stand-alone VTE risk assessment sheet should be stapled to the order set. The order set must be easy to find and restocked regularly because end users are unlikely to go out of their way to download or locate a VTE risk assessment form.

Principle 3. Design reliability into the process.

Do not expect humans to be perfect, especially in the complicated health care setting. Part of the team's job is to engineer higher reliability into the process of protecting patients from hospital-acquired VTE. If the VTE protocol relies solely on traditional methods—order sets, personal checklists, working harder next time, performance feedback, and awareness and training—the team will be disappointed with the results. These traditional methods are helpful, and some are even necessary, but they are not sufficient to achieve breakthrough improvement. The team must design interventions that use at least one of the following high-reliability strategies:

  • The desired action is the default action (i.e., not doing the desired action requires opting out).
  • The desired action is prompted by a reminder or a decision aide.
  • The desired action is standardized into a process (i.e., it takes advantage of work habits or patterns of behavior so that deviation feels weird).
  • The desired action is scheduled to occur at known intervals.
  • Responsibilities for desired action are redundant.

If designed well, the VTE protocol will be an intervention that invokes several of these high-reliability strategies. If it is nested into existing order sets, it can serve as a reminder to prompt ordering of prophylaxis. If admission, postoperative, or transfer order sets are easy to use, always stocked, and easy to find where providers need them, the VTE protocol can be standardized into the process of writing most admission orders. If a clerk or pharmacist is empowered to halt the processing of an order set that has no prophylaxis selected, the responsibility for ensuring VTE prophylaxis can be made redundant. If a member of the care team performs regular reviews of patient medication administration records, responsibility for finding prophylaxis outliers can be scheduled and also made redundant. All these strategies would increase the reliability that patients receive VTE prophylaxis appropriately.

Principle 4. Pilot interventions on a small scale before attempting wide implementation.

No plan survives its first contact with reality. Inevitably there will be glitches with a first pass at anything new. Pilot testing on a small scale creates opportunities to iron out glitches before implementing more broadly. Small-scale pilot tests can be as simple as a 5-minute focus group where five physicians give feedback on several versions of the protocol. The next pilot can consist of trying out the protocol on one patient with one physician and one nurse.

Principle 5. Monitor use of the protocol.

Rolling out the protocol is only a beginning. The team must have a plan that ensures that the VTE protocol is part of the completed admission orders for every patient who enters the medical center.

When providers do not use the protocol or deviate from it, reasons might derive from logistics, patients, providers, and other variables. The team should anticipate variations from the protocol but should capture those instances, learn from them, and take steps to reduce them. The team should ask:

  • Why is the order set not used in some areas?
  • Can it be integrated into other heavily used order sets?
  • Which types of admissions are inadvertently bypassing the protocol?
  • Which patients just do not fit the protocol?
  • Can the protocol be changed so it fits more patients and situations?
  • Which providers would benefit from focused educational efforts?
  • Is the protocol stocked and restocked in all the key areas in the hospital?

While no protocol will fit every patient, the goal is to squeeze needless variability out of medical decisionmaking and ordering. However, the provider must have the freedom to vary from the protocol due to medical necessity. There will always be a need for providers to tailor care to meet the needs of individual patients or to accommodate special circumstances.

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Beyond the Venous Thromboembolism Protocol: Using a "Hierarchy of Reliability"

Consider the "hierarchy of reliability" in Table 4 when planning and executing the VTE prevention initiative. By using this guide and a little ingenuity, a serious institutional effort should be able to achieve the impressive performance gains of level 4. Successful level 5 reliability, as demonstrated in pilots at University of California, San Diego Medical Center and Emory University Hospitals, is within reach of many institutions with electronic medication administration records. 

Table 4. Hierarchy of Reliability

LevelMeaningPredicted Prophylaxis Rate %
1No protocol (i.e., "state of nature")40
2Decision support exists but not linked to order writing or prompts exist within orders but no decision support at hand50
3Protocol well-integrated into orders at point of care65-85
4Protocol enhanced by other QI and high-reliability strategies80-90
5Oversights identified and addressed in real time95+

Level 1. State of Nature

In the unimproved modern hospital, patients receive care that depends solely on their physicians' knowledge, skills, and memory. There is no standardized assessment for VTE risk, and there are no reminders within the real-time flow of care delivery to prompt physicians to order VTE prophylaxis. In this "state of nature," expect approximately 40 percent of patients to be on appropriate VTE prophylaxis at any given moment.

Level 2. Average

Many hospitals that have tried to improve VTE prophylaxis find themselves at Level 2, with only partially effective components of a VTE protocol:

  • A standardized VTE risk assessment to guide the choice of a VTE prophylaxis exists, but it is not well integrated into admission and transfer order sets (e.g., the VTE protocol exists only as a stand-alone form or pocket card).
  • A prompt to order VTE prophylaxis is nested within admission and transfer order sets, but no VTE risk assessment exists to guide the choice of a VTE prophylaxis.

At Level 2, expect approximately 50 percent of patients to be on appropriate VTE prophylaxis at any given moment.

Level 3: VTE Protocol

Level 3 is the entry point for most serious QI efforts: a complete VTE protocol is available. All three elements of a complete VTE protocol are combined within a paper order set or computerized physician order entry. The most effective VTE protocols also have a visual link from the level of VTE risk to the options for appropriate prophylaxis. This visual link enables providers to make a rapid, accurate decision and order appropriate prophylaxis.

At a Level 3 VTE prevention program, not only are providers prompted to order VTE prophylaxis when completing admission or transfer orders, but they also have a standardized VTE risk assessment immediately available to support medical decisionmaking. Level 3 makes it possible for providers to have what they need, when and where they need it, to make an appropriate prophylaxis choice. Expect 65 to 85 percent of patients to be on appropriate VTE prophylaxis at Level 3.

Providers should always retain the freedom to deviate from the protocol when meeting the needs of a given patient. The protocol, with successive refinements, eventually should drive management choices for the majority of patients.

Level 4. Layers of QI Strategies that Leverage the VTE Protocol

For a Level 4 VTE prevention program, all of the conditions of Level 3 exist, but the use of the VTE protocol at admission and transfer is enhanced by additional QI strategies. Level 4 uses high-reliability mechanisms to make it a rare event for a patient to enter the hospital without going through a VTE protocol.

Also at Level 4, any variations from the protocol or adverse effects while on the protocol are studied in depth. The protocol and its integration are continually refined and its use is continually increased based on these events, using the collective intelligence, experience, and investigation of the institution.

Use Table 5 as a source for additional Level 4 ideas. Most of these other strategies leverage the existence of a VTE protocol that is well integrated into the workflow. Providers, nurses, pharmacists, and patients can refer back to the VTE protocol for clarity, confidence, or advocacy. Any additional, layered interventions should include at least one high-reliability mechanism in the design. Expect 80 to 90 percent of patients to be on appropriate VTE prophylaxis at Level 4. This is an extremely impressive level of performance that places the medical center among high performers.

Level 5. Oversights Identified and Mitigated

A Level 5 VTE prevention program represents a dramatic leap in quality. Here the team improves care by a whole order of magnitude, a rare achievement in health care. All the conditions of Level 4 exist, plus there is a strategy to identify and address prophylaxis oversights that inevitably occur. Back at Level 4, at least 1 in 10 patients still fail to receive appropriate prophylaxis. Will the team be satisfied with that considerable gain? It depends on whether the team is merely pursuing excellence relative to "industry standards" or actually pursuing perfection. Instances will always occur where VTE prophylaxis is not ordered on admission or transfer, not replaced with alternatives when contraindications arise, not resumed when suspected contraindications fail to materialize, or not administered properly when ordered (e.g., mechanical prophylaxis). Strategies that identify and mitigate29 these oversights are critical for sustaining prophylaxis prevalence above 90 percent. Level 5 may be impractical or unsustainable without an electronic medication record and reporting mechanism.

A mature Level 5 program will also judge the efficacy of mitigation, and its failures will be immediately remedied. Failure modes of mitigation are systematically cataloged, analyzed, and eliminated. Achieving this level of reliability across an entire hospital represents a pioneering effort in VTE prevention. Level 5 solutions transferable to other institutions represent something transformative for hospital care.

Current as of August 2008
Internet Citation: Chapter 5. Layer Interventions: Preventing Hospital-Acquired Venous Thromboembolism. August 2008. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/professionals/quality-patient-safety/patient-safety-resources/resources/vtguide/vtguidechap5.html