You have a wound that simply will not close. Perhaps it is a diabetic foot ulcer that has been open for months. Perhaps a post-operative wound that weeps and will not heal over. Perhaps a pressure sore after a long period confined to bed. You have changed dressings, maybe twice a week, maybe daily. The wound bed stays coated, the edges macerate, healing does not progress. For exactly this situation, a procedure was developed in the USA in the 1990s that has redefined wound care over the past two decades.
:::answer-block{eyebrow="In short"} Vacuum therapy (Vacuum-Assisted Closure, V.A.C.) is an active wound treatment using controlled negative pressure. An open-pored foam sponge is placed into the wound bed, sealed with an airtight film and connected via a tube to a small suction pump. The negative pressure is typically 75 to 125 mmHg [Argenta and Morykwas, Ann Plast Surg 1997]. Four mechanisms work in parallel: wound oedema and bacterial load are drawn off, microcirculation at the wound edge improves measurably, the wound edges are mechanically contracted, and the cellular micro-deformations at the sponge interface stimulate granulation [Morykwas et al., Ann Plast Surg 1997]. Indications are chronic diabetic ulcers, pressure sores of grade III and above, infected surgical wounds after surgical revision and acute traumatic soft-tissue injuries with a large defect. Dressing changes usually take place every 48 to 72 hours instead of daily, which considerably reduces the burden on patients. After diabetic foot amputation, a randomised trial showed faster and more complete wound healing than under standard care [Armstrong and Lavery, Lancet 2005]. :::
What V.A.C. therapy is and where it comes from
Vacuum therapy was published in 1997 by Louis Argenta and Michael Morykwas at Wake Forest University. Their two papers in the Annals of Plastic Surgery, a clinical case series and a basic-science study, are still regarded as the foundation of modern negative pressure wound therapy [Argenta and Morykwas, Ann Plast Surg 1997]. In the more than two decades since, the procedure has grown from a specialist application in the operating theatre into a widely used method employed in specialised wound clinics, in hospital and increasingly in the home setting as well.
Technically, the system consists of three components. A biocompatible, open-pored foam sponge is cut to fit the wound bed precisely and placed into the wound. A self-adhesive, transparent film seals the sponge and the surrounding skin airtight. A thin tube connects the sponge to a computer-controlled suction pump that generates continuous or intermittent negative pressure. The open wound becomes a controlled, closed system in which the conditions for healing are actively managed.
How controlled negative pressure heals
The therapeutic effect rests on the interplay of several actions that were described in the original studies and have been replicated many times since [Huang et al., Curr Probl Surg 2014].
The negative pressure draws off wound exudate continuously. With the secretion, pro-inflammatory mediators and bacteria are removed from the wound bed. Wound oedema decreases, and the maceration of the wound edges by constant moisture no longer occurs. At the same time, the suction at the sponge interface produces mechanical micro-deformations on the wound surface. This mechanical stimulus prompts cell division and the formation of new, well-perfused granulation tissue [Morykwas et al., Ann Plast Surg 1997]. The wound visibly fills in from the bottom up.
In parallel, the therapy improves microcirculation at the wound edge. More oxygen and more nutrients reach the regenerating tissue. That is a basic prerequisite for any healing. The negative pressure also draws the wound edges gently towards each other and reduces the defect mechanically, which prepares the ground for the later definitive wound closure. The airtight film protects the wound from germs in the surroundings and lowers the risk of a secondary infection [Apelqvist et al., J Wound Care 2017].
When we use V.A.C. therapy
Vacuum therapy is not a first-line procedure for every wound. It is used selectively where fast and stable wound bed preparation makes the difference. The typical indications are clearly set out in the European EWMA recommendations [Apelqvist et al., J Wound Care 2017].
- Deep diabetic foot ulcers: Especially after debridement or partial amputation, when the wound bed has to be prepared for secondary healing or later coverage.
- Pressure sores grade III and IV: For deep, undermined pressure ulcers with exudation and impaired healing.
- Post-operative wound healing disorders: After abdominal, orthopaedic or vascular surgery with wound dehiscence or infection.
- Infected wounds after surgical revision: As a bridge between debridement and definitive wound closure.
- Acute traumatic soft-tissue defects: For large-area injuries with loss of tissue.
- Split-thickness skin grafts: For secure fixation and better take of the graft on the recipient bed. :::
Wound therapy at Dein Team fürs Leben
Specialised care for chronic wounds, diabetic foot ulcers and post-operative healing disorders. V.A.C. therapy, biological wound dressings and debridement under one roof.
More about wound therapyThere are clear contraindications that we check in the consultation: active tumour infiltration in the wound area, untreated osteomyelitis, exposed blood vessels without protection, necrotic tissue without prior debridement. When the indication is set correctly, patients generally tolerate the therapy well.
What the process looks like at Dein Team fürs Leben
In our wound clinic, every V.A.C. treatment begins with a structured assessment. We classify the wound (depth, exudation, signs of infection, blood supply), we decide whether a preparatory debridement is needed, and we check suitability for vacuum therapy. If peripheral arterial disease is suspected, a vascular work-up comes first, because without adequate blood supply even the best wound bed will not heal.
The initial application of the V.A.C. system takes place under sterile conditions at the practice. The foam is cut to fit, the film sealed, the suction calibrated. In most cases the negative pressure is 125 mmHg in continuous mode, lower or in intermittent mode for sensitive wound situations.
Dressing changes typically take place every 48 to 72 hours, depending on bacterial colonisation. That is less often than with classic moist wound dressings, which improves wound rest and considerably reduces the number of painful changes. For very heavily exuding wounds, a tighter change interval may be needed at the start. Modern portable therapy units allow treatment to continue at home, which helps to preserve patients' mobility and quality of life.
The duration of therapy depends on the type of wound and the initial findings. For diabetic foot ulcers, the multicentre randomised trial by Armstrong and Lavery in 2005 showed that under V.A.C. therapy after partial foot amputation, 56 per cent of wounds healed completely, compared with 39 per cent under standard care, and that healing was faster [Armstrong and Lavery, Lancet 2005]. The therapy is therefore a decisive component of structured wound care. It does not replace it. For diabetic wounds, it forms part of the structured care described in our article on diabetic foot syndrome.
A complex wound that will not heal?
In our wound clinic we clarify the cause, check the indication for V.A.C. therapy and coordinate vascular medicine and diabetology where needed. First contact without a referral.
Book a consultation:::faq
How painful is V.A.C. therapy?
Most patients do not find the suction itself painful after a short adjustment period. The dressing changes are more sensitive, especially when the foam grows into the granulation tissue. We reduce this irritation with an interface layer, individual adjustment of the change interval and, where needed, analgesia before the change.
How long does a course of V.A.C. treatment typically take?
That depends heavily on the type of wound, its size and the starting situation. Many wounds need two to six weeks of vacuum therapy to reach a well-granulating wound bed. After that, treatment usually moves into a phase of conditioning or into definitive wound closure by secondary healing, suture or split-thickness skin graft.
Can I continue the therapy at home?
In most cases, yes. Modern devices are portable, battery-powered and built for outpatient use. We instruct you and, where appropriate, your relatives in detail and coordinate regular check-ups at the practice.
Does health insurance cover V.A.C. therapy?
When medically indicated, vacuum therapy in Switzerland is generally covered by compulsory basic health insurance (Grundversicherung). It is billed via TARDOC, the Swiss outpatient tariff. The indication and the documentation are handled by the practice.
What is the difference between V.A.C. therapy and a biological wound dressing such as Kerecis?
The two procedures address different phases and problems. Vacuum therapy actively prepares the wound bed, draws off secretion and stimulates granulation. Biological dressings such as Kerecis fish-skin matrices provide a tissue matrix into which the body's own cells can grow. Both procedures can be used one after the other: first V.A.C., then biological coverage on a well-conditioned wound bed.
Author: Prof. Dr. C. K. Fritz M.Sc., Physician Associate, Pain Medicine, Wound Therapy, Practice Lead, Dein Team fürs Leben.
