Managed care has heightened health care professionals’ awareness of the need to provide cost-effective care without compromising quality, a goal that is typically accomplished by providing evidence-based best practice(s). Management of the arterial access site represents a fundamental component of every procedure performed in the cath lab, and has substantial cost and patient care implications. In most laboratories, the two predominant methods to attain hemostasis following femoral artery sheath removal are 1) application of direct manual pressure, or 2) use of a mechanical closure device. These competing techniques involve a variety of potential tradeoffs related to cost, safety, patient comfort, resource utilization and patient flow through the laboratory (Table 1), and their relative use varies among cath labs.

Topical hemostasis patches have recently emerged as a third option for achieving vascular hemostasis following arterial sheath removal.1-4 Hemostasis patches are topical dressings that are coated with or contain one of a variety of procoagulant materials, and are placed on the skin over the femoral puncture site during manual compression for the purpose of accelerating coagulation. Despite the increasing popularity of these devices, prospective data supporting their utility and safety remains limited. To investigate whether the touted advantages of hemostasis patches might translate into actual clinical benefit, we designed a prospective randomized controlled trial at The University of Rochester to assess the efficacy and safety of one such topical hemostasis patch, the SafeSeal™ Patch (Possis Medical, Minneapolis, MN), following endovascular intervention.

Hemostasis Patches

The production of hemostasis patches for use in the cath lab has grown rapidly over the past few years, and, at present, ten different manufactures market an array of topical hemostasis patches in the United States (Table 1). Of interest, many of the patches produced for use in the cath lab are derived from similar dressings carried by military personnel to be used in the field as a first line therapy for battlefield related trauma.5

Topical patches are used with the goal of reducing the duration of manual compression necessary to attain arterial hemostasis. Manufacturers have also suggested that patches may permit sheath removal at higher levels of anticoagulation, resulting in shortened bedrest durations following sheath removal. Hemostasis patches do not necessitate implantation of foreign materials (e.g., suture, collagen, clips) within and/or adjacent to the femoral artery, and are not contraindicated in the presence of peripheral vascular disease at the sheath insertion site or in instances when the arteriotomy is above the level of the inguinal ligament or distal to the common femoral artery bifurcation. In addition, patches are generally 60 to 80% less expensive than closure devices. While hemostasis pads have been quickly adopted by some laboratories, others have remained skeptical of the clinical effectiveness of these devices, given a paucity of studies confirming their effectiveness.

The SafeSeal Patch

The SafeSeal Patch utilizes a proprietary bioabsorbable plant-derived polysaccharide material, in the form of microporous polysaccharide hemospheres (MPH), to promote hemostasis.6 When the patch is activated, these microscopic spheres are released from the patch as a powder-like substance that contacts the skin and needle tract at the femoral puncture site (Figure 1). The spheres have porous surfaces that result in the absorption of water and low-molecular weight components from blood at the puncture site, which concentrates platelets and clotting proteins to accelerate clot formation and hemostasis. While the procoagulant properties of MPH had been well demonstrated in laboratory experiments, the ability of this material to actually promote hemostasis in the clinical setting following arterial sheath removal had not been examined, prompting the randomized study.

What is the Ideal ACT for Sheath Removal after PCI?

In designing this study to test the efficacy of the SafeSeal Patch, an important consideration was determining the level of anticoagulation at which sheath removal should be undertaken. When manual compression is used to attain hemostasis, sheath removal is usually delayed until the effects of anticoagulants given during the intervention have dissipated. Delaying sheath removal, however, typically results in several hours of additional bedrest following the intervention. The 2005 American College of Cardiology (ACC)/American Heart Association (AHA)/Society of Cardiovascular Angiography and Interventions (SCAI) guidelines for the management of patients undergoing PCI suggest that, when using manual compression, femoral artery sheaths should be removed when the activated clotting time (ACT) is ≤170 seconds, with hemostasis usually achieved after applying direct pressure over the sheath site for 10 to >20 minutes. Interestingly, despite widespread acceptance that sheath removal should be postponed until the level of anticoagulation falls to ≤170 seconds following PCI, few investigators have systematically attempted to define the ideal ACT for sheath removal.

In a recent study, the group at the University of Rochester evaluated the relationship between the ACT at the time of sheath removal and the duration of manual compression required to obtain hemostasis following PCI.7 Surprisingly, it was found that time needed to obtain hemostasis was not prolonged when sheaths were removed at an ACT threshold of <250 seconds rather than at the traditional level of <170 seconds. In addition, sheath removal at the higher ACT threshold was associated with a significant reduction in bedrest time without an increase in bleeding events compared to sheath removal at the lower ACT limit of <170 seconds.

How Much Bedrest is Necessary after Sheath Removal?

Another poorly understood aspect of sheath removal practices relates to the duration of bedrest necessary after hemostasis has been attained using manual compression. Most patients, especially those with arthritis and back problems, find prolonged immobilization associated with bedrest uncomfortable. In addition, patients typically require closer monitoring during bedrest, which increases costs related to nursing staff time and effort. The ACC/AHA/SCAI guidelines note that patients traditionally are required to remain in bed with the head of their bed at <30 degrees and the affected leg kept fairly immobilized for 4-6 hours. Two small studies have suggested that reducing bedrest time to 2 hours appears safe following PCI.8,9 Likewise, a recent analysis by Tagney and Lackie reported that femoral wound site complication rates were not adversely affected by reducing bedrest times following diagnostic or interventional procedures.10 Drawing from these recent studies, the SafeSeal Patch study provided the opportunity to examine whether the use of a hemostasis patch might permit not only earlier sheath removal at higher ACT levels, but also allow shorter bedrest durations following sheath removal.

SafeSeal Study: Design and Results

It was hypothesized that use of the SafeSeal Patch would be associated with reductions in time to hemostasis and time to ambulation compared to standard manual compression following percutaneous coronary and peripheral intervention. The trial was supported by a grant from Possis Medical. One hundred-fifty (150) patients who underwent coronary or peripheral arterial intervention through a 6 French (F) femoral sheath were randomized to sheath removal using either manual compression with adjunctive use of the SafeSeal Patch, or conventional manual pressure alone. To examine the potential benefits of earlier sheath removal and ambulation among subjects enrolled in the study, sheaths were removed following the intervention when the ACT fell below 250 seconds, and patients were permitted to ambulate under supervision after only 2 hours of bedrest once hemostasis had been attained. Among those enrolled in the study, the mean age was 65 years, 82% were male, 27% had diabetes mellitus, and IIb/IIIa antagonist therapy was used during the intervention in 67% of patients.

The study findings supported the hypothesis that use of the SafeSeal Patch is associated with accelerated hemostasis. The mean time to hemostasis, defined as the duration of manual compression necessary to achieve hemostasis following sheath removal, was significantly lower among patients randomized to the hemostasis patch (11.8 ± 3.6 vs. 13.8 ± 5.8 min, p=0.02). Despite sheath removal at the higher ACT threshold of <250 seconds, complete hemostasis was achieved within 10 minutes in 73% of patients treated with the SafeSeal Patch versus 55% of patients who received manual compression alone (p=0.03). The median time to ambulation, defined as the time from the end of the interventional procedure to ambulation, was reduced by one hour among patients in the hemostasis patch arm (2.8 vs. 3.8 hrs, p=0.03). While a larger sample size would be necessary to more accurately assess complication rates, bleeding complications were rare, with only one major bleeding event (0.7%) noted in the study, consisting of a retroperitoneal hematoma that occurred in a patient in the SafeSeal arm.11

Our Sheath Removal Algorithm

The findings of this study have led to an evolution of sheath removal practices in our laboratory. Most notably, when manual compression is used following an interventional procedure, sheath removal is no longer delayed until the ACT falls below 170 seconds. Instead, the ACT is checked at the end of the intervention and if the level is <250 seconds, the 6F sheath is usually removed using a hemostasis patch before the patient leaves the procedure room. When bivalirudin rather than unfractionated heparin is used during PCI, it has been found that the ACT typically remains above 250 seconds for 1-2 hours following the procedure, making immediate sheath removal less likely. While many of the staff responsible for manual compression in the laboratory were initially reluctant to undertake sheath removal at higher ACT levels for fear that much longer hold times would be required, this perception is no longer present. The advantages of earlier sheath removal with adjunct use of hemostasis pads have become apparent with experience, and many once skeptical personnel now actively promote the practice.

Because of advantages with respect to the flow of patients through the cath lab, closure devices likewise remain an important tool in a substantial proportion of patients following PCI. If a patient is a potential candidate for a closure device, a femoral angiogram is performed through the sheath immediately following the interventional procedure. Patients ineligible for closure device implantation include those with severe calcification or a prior bypass graft involving the femoral artery, those at higher risk of infection with implantation of foreign material, and very thin patients without sufficient subcutaneous tissue to accommodate the clip, suture, or collagen associated with the closure device. If the femoral angiogram confirms that the puncture site is within the common femoral artery and otherwise favorable anatomy is present, a closure device is used. If a patient is ineligible for closure device use, which occurs in ~20% of individuals, the sheath is removed with a closure patch at an ACT threshold <250 seconds. Bedrest is typically maintained for 2-4 hours after hemostasis is obtained, based on operator preference. With regard to patch selection, it is important to emphasize that while a variety of patches have been used in the lab, at present the SafeSeal Patch is the only device we have tested in a prospective randomized manner with documented reductions in time to hemostasis and time to ambulation compared to manual compression alone.

Summary

The laboratory’s clinical experience with the SafeSeal Patch, corroborated by the trial results presented above, support the efficacy of the product as a means to accelerate hemostasis following arterial sheath removal. The device has become an established alternative to the use of closure devices or stand-alone manual compression in the lab, and further clinical experience will help to more fully define the role of the SafeSeal Patch in clinical practice.

The authors can be contacted at vicki_rocco@urmc.rochester.edu or craig_narins@urmc.rochester.edu.

This article received double-blind peer review from selected members of the Cath Lab Digest editorial board.