What Is the Benefit of Instillation Therapy

Over the past decade, the concept of proper wound bed preparation as a means to improve wound healing has gained increasing attention. The principles of wound bed preparation include proper wound debridement, managing wound exudates, and managing bioburden. Proper wound bed preparation creates an optimal wound healing environment. The presence of necrotic tissue or eschar is known to impede healing. Likewise, the presence of abnormally high levels of bacteria may also impede healing. These impediments to wound healing may in part be removed by practices such as wound irrigation. Cleansing the wound by using an irrigant to remove loosely attached bacteria and cellular or other debris may decrease wound complications, thereby allowing the wound to heal in a timely fashion. Typically, wound irrigation is conducted at pressures less than 103.4 kPa using an irrigant that does not cause trauma to the surrounding tissue. Typical devices used to deliver irrigants to wounds include spray bottles, syringes, squeeze bottles, and pulsatile lavage devices. We consider all these types of approaches to fall under the category of instillation therapy. The clinical application of instillation therapy for treating wounds was first described by Fleischmann et al in 1998. Since then, several clinical articles have described various applications of instillation therapy, most of which address the treatment of wound infections. For example, Gabriel et al reported the use of instillation therapy for treating soft tissue infection. They showed that instilling silver nitrate was effective at reducing bioburden, time to wound closure, and time to hospital discharge. Others have followed with similar clinical results. Schintler et al and Timmers et al showed that instilling polyhexanide solution was effective at treating soft tissue necrotizing fasciitis and osteomyelitis. Even though the utility of wound irrigation for infected wounds is an accepted practice, cross-contamination from the splatter, which may be caused during the instillation process, is a safety concern to both the patient and the clinician. In a recent study, Angobaldo et al showed that bacteria from pulsatile lavage–treated wounds could be captured 3 feet away from the wound. The spread of organisms and especially resistant organisms in the hospital environment is a growing concern. Studies have demonstrated that methicillinresistant Staphylococcus aureus or vancomycin-resistant enterococci can be detected on the protective gowns and gloves of up to 67% of health care workers tested. With the increasing prevalence of antibiotic-resistant organisms and nosocomial infections, it is important that techniques be used to prevent the spread and possible cross-contamination of infection. This is especially true with any type of instillation therapy where outbreaks of infection have been traced back to facility contamination caused by the therapy itself. It is likely that such outbreaks could be prevented by better containment of splatter during the instillation procedure. In addition to the treatment of infection, there are a number of other potential uses for instillation therapy. The medical and scientific community recognizes additional clinical benefits for instillation therapy. Nagai et al reported that instilling the protein sericin has a potent effect on wound healing and corneal epithelialization in a rodent model. Jerome suggested using instillation therapy to provide pain management during and after dressing changes. The addition and removal of a liquid solution from a wound bed may have other clinical benefits. Instilling a wound with lactated Ringer’s solution or saline may dilute the bioburden and prevent potential clinical infections. At the same time, instillation therapy with saline may help remove necrotic tissues and reduce the level of proinflammatory mediators, leading to a shift toward the proliferative phase of healing. Reducing the amount of early inflammation may also lead to better tissue remodeling and tissue quality. Recently, Acosta et al postulated that chronic and hyperinflammation is detrimental to the repair of diabetic foot wounds. They highlighted the need for smart prophylactic interventions to reduce chronic inflammation. We believe that instillation therapy may address this clinical need for a therapeutic intervention. In summary, there are many benefits to applying instillation therapy in the treatment of wounds including lower extremity wounds. Depending on what solution is being instilled, instillation therapy can help resolve clinical infections, manage pain, reduce bioburden, and may even potentially aid in epithelialization. All these clinical benefits will help