CiNPWT Lower Extremity Amputations (Closed Incision Neagtive Pressure Wound Therapy)

The objective of this study is to evaluate prospectively the effect of a novel application of Closed Incision Negative Pressure Wound Therapy(CiNPWT), as delivered by the V.A.C. Ulta™ Therapy System (3M, USA) in individuals who have undergone a Lower Extremity Amputation(LEA) compared with standard of care compression wrapping and wound care post-LEA.

This a pilot-controlled exploratory trial including approximately 6-10 individuals who have undergone LEA (trans-metatarsal or higher) randomized between intervention (novel application of CiNPWT) and a control group (standard care).

The objective of this study is to evaluate prospectively the effect of a novel application of Closed Incision Negative Pressure Wound Therapy (CiNPWT), as delivered by the V.A.C. Ulta™ Therapy System (3M, USA) in individuals who have undergone a Lower Extremity Amputation (LEA) compared with standard of care compression wrapping and wound care post-LEA.

Specific objectives:

1. Collect demographics and relevant data (e.g., risk factors and comorbidities) to compare intervention and control groups.
2. Measure post-surgical outcomes and compare both groups.

STUDY DESIGN

This a pilot-controlled exploratory trial including approximately 6-10 individuals who have undergone LEA (trans-metatarsal or higher) randomized between intervention (novel application of CiNPWT) and a control group (standard care).

DEVICE INFORMATION

The V.A.C. Ulta™ Therapy System (3M, USA) is a non-invasive wound closure system that uses controlled, localized negative pressure to promote healing in chronic and acute wounds. The subatmospheric (ie. negative) pressure system uses latex-free and sterile polyurethane or polyvinyl alcohol foam dressings that are individualized at the bedside to the appropriate size for every patient, and then covered with an adhesive drape to create an airtight seal. A SensaT.R.A.C.™ Pad directly contacts the foam dressing, and accurately senses, monitors, and maintains the target pressure at the wound site to provide controlled negative pressure. Tubing attached to the SensaT.R.A.C.™ Pad connects to a fluid collection canister contained in a programmable, portable, computer-controlled vacuum pump creating negative pressure at the wound surface interface.

Amputation (and revision/re-amputation) is a resection of a segment of a limb through a bone or through a joint.

Major amputation: Any resection proximal to the ankle.

Major amputation levels:

TT = transtibial amputation: amputation through the tibia and fibula (frequently referred to as "below knee amputation").

KD = knee disarticulation: amputation through the knee (frequently referred to as "through knee amputation").

TF = transfemoral amputation: amputation through the femur (frequently referred to as "above knee amputation").

Minor amputation: Any resection distal to the ankle.

Minor amputation levels:

TMA= transmetartarsal amputation.

The level will be determined using the electronic medical record of the patients and by the health care providers observations.

Wound dehiscence (partial or total) is a surgery complication where the incision reopens. Clinically reported by the health care providers. This will be also evaluated with digital photographs.

Infection at the surgical site and/or cellulitis of the residual limb are pathological states caused by invasion and multiplication of microorganisms in host tissues accompanied by tissue destruction and/or a host inflammatory response. This is usually based on soft tissue infection clinical criteria from Infectious Disease Society of America (IDSA) and will be reported by the health care provider.

Closed wound, defined as complete epithelialization at the surgical site, will be based on the health provider's clinical decision combined with medical record documentation. Determination is based on data from wound assessments and photographs performed by the treating clinician and documented in the Tissue Analytics wound imaging software. Photographs will be taken during patient visits (no more than 3x/wk) and if present, wound size, and tissue color percentages will be calculated by Tissue Analytics software. Any wound depth present will be measured manually by the treating therapist and entered into the Tissue Analytics system. Additional wound assessment characteristics that will be documented include periwound color and condition, drainage type or amount, and tissue type assessment. Agreement between clinician's documentation of closure and photographic measurements will be used to ascertain time to closure.

The tolerability/acceptability of CiNPWT will be measured:

* Pain which is a physical suffering or discomfort caused by CiNPWT is usually reported by the patient using the visual analogue scale at each visit.
* Anxiety about the treatment using Hamilton Anxiety Rating Scale (HAM-A)
* Quality of life using the Short Form-36 Questionaire

Baseline characteristics, risk factors and comorbidities will be extracted from the electronic medical record and validated with physical examination. Investigations can be done as necessary to complete missing data such as presence/absence of neuropathy, vascular status, etc., using best practice at the initial evaluation. As an example, blood samples will be obtained at the first evaluation to assess Hemoglobin A1c. If a patient is deemed at nutrition risk based on a nutrition screen done by nursing (Malnutrition Screening Tool), a dietitian will be consulted, and dietary supplementation will be initiated as needed.

All unscheduled or emergency visits will be listed.

At each encounter, the time to complete the treatment including dressings and compression (intervention and control) will be recorded by the clinician in the Electronic Medical Record.

Eligibility Criteria:
Inclusion criteria to select the participants (intervention and control):

* Individual aged 18 years or older
* Individual with a closed incision following LEA (transmetatarsal or proximal)
* Individual presents with adequate perfusion based on WIfI ischemia component score of less than 2 (\>30mm Hg TCPO2 or higher at region of amputation)
* Individual presents with no residual surgical site infection (WIfI grade 0) post LEA
* Individual is competent to make their own medical decisions

Exclusion criteria (intervention and control):

* Individual presents with any defined contraindications to NPWT (e.g., allergy).
* Individual presents with residual acute osteomyelitis (after amputation).
* Individual with collagen vascular disease or malignant disease in the wound
* Individual has uncontrolled hyperglycemia (glycosylated hemoglobin \[HbA1c\]\>12%).
* Individual is currently taking corticosteroids, immunosuppressive drugs, or chemotherapy and is not on stable course of therapy as determined by principal investigator
* Individual has a history of local radiation therapy that could impact the edema of the amputated limb.
* Individual has pre-existing conditions contributing to residual limb edema (i.e., nephropathy, congestive heart failure, primary lymphedema, etc.).

Withdrawal of individuals:

* Voluntary withdrawal
* Death
* Lost to follow-up
* Termination of compression therapy (control or intervention group)