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. Application of dressings to maintain a moist wound environment, and
      2. Debridement of necrotic tissue if present, and
      3. Documentation of evaluation, care, and wound measurements by a licensed medical professional, 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 0430 - 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., pre-operative flap or graft), other than complications resulting in an open abdomen, where there is documentation of the medical necessity for accelerated formation of granulation tissue which can not 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 1 wound dressing set for multiple wounds on a member.  Therefore, more than 1 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. 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
   2. 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
   3. In the judgment of the treating physician, adequate wound healing has occurred to the degree that NPWT may be discontinued, or
   4. Once equipment or supplies are no longer being used for the member, whether or not by the physician's order; or

   5. When criteria under section on Continued Medical Necessity above, cease to be met.

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 1 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 its effectiveness for these indications has not been established.

Aetna considers the use of chemotherapeutic agents (e.g. doxycycline and insulin) in continuous-instillation NPWT experimental and investigational because its effectiveness has not been established.

Aetna considers the use of non-powered NPWT devices (e.g., the Smart Negative Pressure [SNaP] Wound Care System) experimental and investigational because their effectiveness has not been established.

See also CPB 0244 - Wound Care.

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

Negative pressure wound therapy 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.

Negative pressure wound therapy 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 and Land, 2001; Wasiak and Cleland, 2007; Ubbink et al, 2008), Washington State Department of Labor and Industries (2003), Canadian Coordinating Office for Health Technology Assessment (Fisher and 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 and Jones, 2006; Nelson and 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. A systematic evidence review by the National Institute for Health and Clinical Excellence (NICE, 2009) found inadequate evidence for the use of NPWT in open abdominal wounds.  The NICE assessment concluded that "[c]urrent evidence on the safety and efficacy of negative pressure wound therapy (NPWT) for the open abdomen is inadequate in quality and quantity. There has been concern about the occurrence of intestinal fistulae associated with this procedure but there is currently no evidence about whether NPWT is the cause."

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.

Vikatmaa et al (2008) conducted a systematic review of the literature on the safety and effectiveness of NPWT for problematic wounds.  A total of 14 RCTs were included.  Trials included patients with: (i) pressure wounds, (ii) post-traumatic wounds, (iii) diabetic foot ulcers, and (iv) miscellaneous chronic ulcers.  Only 2 trials were classified as high quality studies, whereas the remaining were classified as having poor internal validity.  The authors concluded that (i) reliable evidence on the effectiveness of NPWT is scarce, (ii) tentative evidence indicates that the effectiveness of NPWT is at least as good as or better than current local treatment for wounds, and (iii) the need for large high-quality randomized studies is apparent.

Blume et al (2008) evaluated the safety and clinical efficacy of NPWT compared with advanced moist wound therapy (AMWT) (predominately hydrogels and alginates) to treat foot ulcers in diabetic patients in a multi-center randomized controlled trial (n = 342).  The mean age was 58 years and 79 % of subjects were male.  Complete ulcer closure was defined as skin closure (100 % re-epithelization) without drainage or dressing requirements.  Patients were randomly assigned to either NPWT or AMWT (predominately hydrogels and alginates) and received standard off-loading therapy as needed.  The trial evaluated treatment until day 112 or ulcer closure by any means.  Patients whose wounds achieved ulcer closure were followed at 3 and 9 months.  Each study visit included closure assessment by wound examination and tracings.  A greater proportion of foot ulcers achieved complete ulcer closure with NPWT (73 of 169, 43.2 %) than with AMWT (48 of 166, 28.9 %) within the 112-day active treatment phase (p = 0.007).  The Kaplan-Meier median estimate for 100 % ulcer closure was 96 days (95 % confidence interval [CI]: 75.0 to 114.0) for NPWT and not determinable for AMWT (p = 0.001).  Patients who received NPWT experienced significantly (p = 0.035) fewer secondary amputations.  The proportion of home care therapy days to total therapy days for NPWT was 9,471 of 10,579 (89.5 %) and 12,210 of 12,810 (95.3 %) for AMWT.  In assessing safety, no significant difference between the groups was observed in treatment-related complications such as infection, cellulitis, and osteomyelitis at 6 months.  The authors concluded that NPWT appears to be as safe as and more efficacious than AMWT for the treatment of diabetic foot ulcers.

The Centers for Medicare and Medicaid Services (CMS) partnered with the Agency for Healthcare Research and Quality (AHRQ) and commissioned a review of NPWT devices.  AHRQ contracted with the ECRI Institute Evidence-based Practice Center to perform the review.

A technology assessment report on NPWT (Sullivan et al, 2009) prepared for the Agency for Healthcare Research and Quality found that systematic reviews of NPWT reveal the following important points about the current state of the evidence on this technology: (i) all of the systematic reviews noted the lack of high-quality clinical evidence supporting the advantages of NPWT compared to other wound treatments; the lack of high-quality NPWT evidence resulted in many systematic reviewers relying on low-quality retrospective studies to judge the efficacy of this technology, (ii) no studies directly comparing different NPWT components (e.g., foam versus gauze dressings) were identified by any of the reviewers, and (iii) NPWT must be evaluated according to wound type; wound healing varies according to the type of wound being treated and NPWT benefits described for one wound type cannot be assumed to apply to other wound types. 

The assessment stated that the available evidence cannot be used to determine a significant therapeutic distinction of a NPWT system.  In addition, due to the lack of studies comparing one NPWT system to another NPWT system the severity of adverse events for 1 NPWT system compared to another could not be determined.  The report concluded, "Clinical research on NPWT capable of indicating if any one NPWT system or component provides a significant therapeutic distinction requires study design and conduct that will minimize the possibilities for bias.  Important study design features that were not typically reported such as concealment of allocation, reporting of randomization methods, use of power analysis to ensure adequate study size, blinding wound assessors, and reporting of complete wound healing data will improve the internal validity and the informativeness of the studies."

Negative pressure wound therapy uses a reticulated sponge and subatmospheric pressure to facilitate healing of a variety of wounds.  The therapy appears to assist wound healing by decreasing wound bacterial burden and edema while facilitating granulation tissue formation.  The latest development in NPWT allows clinicians to instill continuously a treatment solution and suspension into the wound.  A variety of wound chemo-therapeutic agents such as insulin, which acts as a growth factor, may prove helpful in this aspect.  Scimeca and colleagues (2010a) presented a case report in which insulin was used as a chemo-therapeutic agent in continuous-instillation NPWT.  To the authors' knowledge, this is the first report in the literature describing this method of delivery.  Furthermore, Scimeca et al (2010b) described a real-time streaming therapy of a variety of wound chemo-therapeutic agents through NPWT.  Doxycycline, which acts as a competitive inhibitor of matrix metalloproteinases and tumor necrosis factor alpha and further decreases inflammation through the reduction of nitrous oxide production, may prove helpful when delivered in this manner.  To the authors' knowledge, this is the first report in the literature describing this method of delivery of doxycycline.  The clinical value of chemo-therapeutic agents in continuous-instillation NPWT nees to be ascertained in randomized, controlled clinical trials.

A non-powered NPWT device, the Smart Negative Pressure (SNaP) Wound Care System from Spiracur, is a class II device that received 510(k) marketing clearance from the Food and Drug Administration in 2010 and is designed to remove small amounts of exudate from chronic, traumatic, dehisced, acute, subacute wounds and diabetic and pressure ulcers.  The lack of well-designed comparative studies with large number of individuals using the non-powered NPWT system is insufficient to draw conclusions about its impact on health outcomes with the device and in comparison with current care.

The European Pressure Ulcer Advisory Panel's clinical practice guideline on pressure ulcer treatment (2009) recommended conventional NPWT therapy, but did not mention non-powered NPWT.

Appendix

Contraindications for Negative Pressure Wound Therapy (NPWT):

NPWT is contraindicated in the presence of any the following:

• Cancer present in the wound; or
• Inadequately debrided wounds; granulation tissue that will not form over necrotic tissue; or
• Presence of untreated coagulopathy; or
• The presence in the wound of necrotic tissue with eschar, if debridement is not attempted; or
• The presence of a fistula to an organ or body cavity within the vicinity of the wound; or

• Untreated osteomyelitis or spesis within the vicinity of the wound.

List of Negative Pressure Wound Therapy (NPWT) Devices*

ActiV.A.C.® Therapy Unit
Engenex® Advanced NPWT System
Exusdex® wound drainage pump
EZCARE Negative Pressure Wound Therapy
Genadyne A4 Wound Vacuum System
InfoV.A.C.® Therapy Unit
Invia Liberty Wound Therapy
Invia Vario 18 ci Wound Therapy
Medela® Invia Liberty pump
Mini V.A.C.®
NPD 1000 Negative Pressure Wound Therapy System
Prodigy™ NPWT System (PMS-800 and PMS-800V)
PRO-II™
PRO-I™
RENASYS™ EZ Negative Pressure Wound Therapy
SVEDMAN™ and SVED™ Wound Treatment Systems
V.A.C.® ATS™
V.A.C.® Freedom™
V.A.C.® Instill Device
V.A.C.® Therapy Unit
V.A.C.® (Vacuum Assisted Closure™)
V1STA Negative Pressure Wound Therapy
Venturi™ Negative Pressure Wound Therapy

* These devices have U.S. Food and Drug Administration 510(k) clearance for marketing in the United States.  This list is not all-inclusive.