Aetna considers negative pressure wound therapy (NPWT) pumps medically necessary, when either of the following criteria (I or II) is met:

1. Ulcers and Wounds in the Home Setting

   The member has a chronic Stage III or IV pressure ulcer (see appendix below), neuropathic ulcer (e.g., diabetic ulcer), venous or arterial insufficiency ulcer, or a chronic ulcer of mixed etiology present for at least 30 days. A complete wound therapy program described by criterion A and criterion B, C, or D below, as applicable depending on the type of wound, has been tried or considered and ruled out prior to application of NPWT.

   1. For all ulcers or wounds, the following components of a wound therapy program must include a minimum of all of the following general measures, which should either be addressed, applied, or considered and ruled out prior to application of NPWT:

      1. Documentation of evaluation, care, and wound measurements by a licensed medical professional, and
      2. Application of dressings to maintain a moist wound environment, and
      3. Debridement of necrotic tissue if present, and

      4. Evaluation of and provision for adequate nutritional status.

   2. For Stage III or IV pressure ulcers:

      1. The member has been appropriately turned and positioned, and
      2. The member has used a group 2 or 3 support surface for pressure ulcers on the posterior trunk or pelvis (see CPB 430 - Pressure Reducing Support Surfaces) (Note: a group 2 or 3 support surface is not required if the ulcer is not on the trunk or pelvis), and

      3. The member's moisture and incontinence have been appropriately managed.

   3. For neuropathic (e.g., diabetic) ulcers:

      1. The member has been on a comprehensive diabetic management program, and

      2. Reduction in pressure on a foot ulcer has been accomplished with appropriate modalities.

   4. For venous insufficiency ulcers:

      1. Compression bandages and/or garments have been consistently applied, and

      2. Leg elevation and ambulation have been encouraged.

2. Ulcers and Wounds Encountered in an Inpatient Setting

   1. An ulcer or wound (described in section I above) is encountered in the inpatient setting and, after wound treatments described in I-A through I-D for the various types of ulcers above have been tried or considered and ruled out, it is necessary to initiate NPWT.

   2. The member has complications of a surgically created wound (e.g., dehiscence) or a traumatic wound (e.g., preoperative flap or graft) where there is documentation of the medical necessity for accelerated formation of granulation tissue which cannot be achieved by other available topical wound treatments (e.g., other conditions of the member that will not allow for healing times achievable with other topical wound treatments).
      

   In either situation, II-A or II-B, NPWT will be considered medically necessary when treatment continuation is ordered beyond discharge to the home setting.

   Note: NPWT pumps must be capable of accommodating more than one wound dressing set for multiple wounds on a member. Therefore, more than one NPWT pump billed per member for the same time period is considered not medically necessary.

3. Continued Medical Necessity

   For wounds and ulcers described in sections I and II above, once placed on an NPWT pump and supplies, in order to document continued medical necessity, a licensed medical professional must do the following:

   1. On a regular basis, directly assess the wound(s) being treated with the NPWT pump, and supervise or directly perform the NPWT dressing changes, and

   2. On at least a monthly basis, document changes in the ulcer's dimensions and characteristics.

4. Discontinuation Criteria

   For wounds and ulcers described in sections I and II above, an NPWT pump and supplies will be considered as not medically necessary with any of the following, whichever occurs earliest:

   1. When criteria under section on Continued Medical Necessity above, cease to be met; or
   2. In the judgment of the treating physician, adequate wound healing has occurred to the degree that NPWT may be discontinued; or
   3. Any measurable degree of wound healing has failed to occur over the prior month. There must be documentation of quantitative measurements of wound characteristics including wound length and width (surface area), or depth, serially observed and documented, over a specified time interval. The recorded wound measurements must be consistently and regularly updated and must have demonstrated progressive wound healing from month to month, or
   4. Four months (including the time NPWT was applied in an inpatient setting prior to discharge to the home) have elapsed using an NPWT pump in the treatment of any wound. The medical necessity of NPWT beyond 4 months will be given individual consideration based upon required additional documentation; or

   5. Once equipment or supplies are no longer being used for the member, whether or not by the physician's order.

5. Supplies

   1. Up to a maximum of 15 dressing kits per wound per month is considered medically necessary unless there is documentation that the wound size requires more than one dressing kit for each dressing change.

   2. Up to a maximum of 10 canister sets per month is considered medically necessary unless there is documentation showing a large volume of drainage (greater than 90 ml of exudate per day). For high volume exudative wounds, a stationary pump with the largest capacity canister must be used. Excess utilization of canisters related to equipment failure (as opposed to excessive volume drainage) is not considered medically necessary.

Note: Staging of pressure ulcers used in this policy is as follows:

Aetna considers NPWT experimental and investigational for the treatment of open abdominal wounds (e.g., abdominal compartment syndromes, traumatic injuries, and severe intra-abdominal sepsis), pilonidal sinus disease, deep sternal wound infection, and all other indications other than those noted in Sections I and II above because their effectiveness for these indications has not been established.

See also CPB 244 - Wound Care.

This policy is based in part upon Medicare DMERC medical necessity criteria for negative pressure wound therapy (NPWT) pumps.

NPWT is the controlled application of subatmospheric pressure to a wound using an electrical pump to intermittently or continuously convey subatmospheric pressure through connecting tubing to a specialized wound dressing which includes a resilient, open-cell foam surface dressing, sealed with an occlusive dressing that is meant to contain the subatmospheric pressure at the wound site and thereby promote wound healing.  Drainage from the wound is collected in a canister.  Brands of NPWT pumps include the V1 Versatile Wound Vacuum System (BlueSky Medical Group, Carlsbad, CA), which was cleared by the FDA in August 2004 based on a 510(k) premarket notification, and the Vacuum Assisted Closure (VAC) System (Kinetic Concepts Inc., San Antonio, TX), which was cleared by the FDA in May 1995 based on a 510(k) premarket notification.

NPWT has been used to promote healing of chronic wounds and pressure ulcers (decubitus ulcers) by creating controlled negative pressure over the wound that is thought to increase local vascularity and oxygenation of the wound bed, reduce edema by evacuating wound fluid, and remove exudate and bacteria.

More than a dozen systematic evidence reviews produced by independent organizations have questioned the quality of the evidence supporting the use of NPWT, including systematic evidence reviews published by the Cochrane Collaboration (Evans & Land, 2001; Wasiak & Cleland, 2007), Washington State Department of Labor and Industries (2003), Canadian Coordinating Office for Health Technology Assessment (Fisher & Brady, 2003), Australian Safety and Efficacy Register of New Interventional Procedures -- Surgical (Pham, et al., 2003), NHS Quality Improvement Scotland (NHS QIS, 2003), Centre for Clinical Effectiveness (Higgins, 2003), Agency for Healthcare Research and Quality (Samson, et al., 2004), Technology Assessment Unit of McGill University Health Centre (Costa, et al., 2005), Institute for Quality and Efficiency in Health Care (IQWiG, 2006), Ontario Ministry of Health and Long-Term Care (MAS, 2004; MAS, 2006), Galician Agency for Health Technology Assessment (AVALIA-T, 2005), and BMJ Clinical Evidence (Nelson & Jones, 2006; Nelson & Penthrick, 2007).

Control of intra-abdominal fluid secretion, facilitation of abdominal exploration, and preservation of the fascia for abdominal wall closure is a major challenge in the management of patients with an open abdomen.  Vacuum-assisted therapy has been reported to help meet the challenges of managing the open abdomen and may be useful in patients with abdominal compartment syndromes, traumatic injuries, and severe intra-abdominal sepsis.  In a review on the management of patients with open abdomen, Kaplan (2004) concluded that controlled clinical studies are needed to establish the safety and effectiveness of this treatment approach and to facilitate the development of treatment guidelines to help manage an increasingly common group of patients who might benefit from this treatment approach.

Schimmer and colleagues (2007) stated that there are many primary modalities for managing deep sternal wound infection (DSWI) following cardiac surgery, namely surgical debridement with primary re-closure in conjunction with irrigation, VAC, and primary or delayed flap closure.  These researchers examined if there is consensus on the primary management of DSWI using one method as a single line therapy or a combination of these procedures.  Therefore, a questionnaire with regards to the primary treatment modalities of DSWI was distributed to all 79 German heart surgery centers.  All replied to the questionnaire -- VAC is used in 28/79 (35 %) heart centers as the 'first-line' treatment, 22/79 (28 %) perform primary reclosure in conjunction with a double-tube irrigation/suction system, and in 29/79 (37 %) clinics both treatment options were used according to intra-operative conditions.  Mostly, as a primary management of DSWI two treatment modalities are mainly in use: primary reclosure coupled with a double-tube suction/irrigation system and VAC.  The current understanding is based purely on retrospective studies, not evidence-based medicine.  Since prospective randomized controlled trials (RCTs) have not yet been performed, controlled clinical trials comparing these treatment modalities are pivotal to define evidence for patients presenting with DSWI.

Morris et al (2007) noted that although NPWT appears effective, it remains unknown if it is more effective than other wound closure techniques.  In addition, although many uncontrolled, non-randomized studies describing the effectiveness of this therapy have been published, few prospective RCTs have been conducted.  Small sample sizes, variable outcome measures across studies, and significant methodological problems in the available RCTs further limit the conclusions that can be drawn regarding the relative effectiveness of vacuum-assisted wound closure.  Analysis of these data provided weak evidence to suggest that NPWT is superior to saline gauze dressings in healing chronic wounds.  The authors concluded that RCTs comparing healing, costs of care, patient pain, and quality-of-life outcomes of this treatment to non-gauze type dressings and other treatment modalities are needed.

Gregor et al (2008) examined the clinical effectiveness and safety of negative NPWT compared with conventional wound therapy; RCTs and non-RCTs comparing NPWT and conventional therapy for acute or chronic wounds were included in this review.  The main outcomes of interest were wound-healing variables.  After screening 255 full-text articles, 17 studies remained.  In addition, 19 unpublished trials were found, of which 5 had been prematurely terminated.  Two reviewers independently extracted data and assessed methodological quality in a standardized manner.  Seven RCTs (n = 324) and 10 non-RCTs (n = 278) met the inclusion criteria.  The overall methodological quality of the trials was poor.  Significant differences in favor of NPWT for time to wound closure or incidence of wound closure were shown in 2 of 5 RCTs and 2 of 4 non-RCTs.  A meta-analysis of changes in wound size that included 4 RCTs and 2 non-RCTs favored NPWT (standardized mean difference: RCTs, -0.57; non-RCTs, -1.30).  The authors concluded that although there is some indication that NPWT may improve wound healing, the body of evidence available is insufficient to clearly prove an additional clinical benefit of NPWT.  Furthermore, the large number of prematurely terminated and unpublished trials is reason for concern.

Appendix

Contraindications for Negative Pressure Wound Therapy (NPWT):

NPWT is contraindicated in the presence of any the following:

• The presence in the wound of necrotic tissue with eschar, if debridement is not attempted; or
• Untreated osteomyelitis within the vicinity of the wound; or 
• Cancer present in the wound; or 
• The presence of a fistula to an organ or body cavity within the vicinity of the wound.