Juggling risk to reduce amputations: The three-ring circus of infection, ischemia and tissue loss-dominant conditions
- Southern Arizona Limb Salvage Alliance, Department of Surgery, University of Arizona College of Medicine, United States
Wound classification systems have evolved from linear systems describing only one factor to more matrix-oriented, allowing wider clinical applicability. We suggest that, in a similar fashion to wound classification, a flexible long-term management philosophy should be dynamic and conceptually inclusive. We visualize amputation prevention as the management of three partially intersecting rings whose complex interplay competes for dominance at any given time during the life of the patient and his or her limb. These rings of dominance involve tissue loss, ischemia, and infection and are constantly in motion. Once a patient has a wound or has healed a wound, one might consider this flexible approach to management and assessment. A question that might be asked would be: “At this moment, which ring does this patient’s biggest problem lie? Infection? Ischemia? Tissue Loss? Combinations?” This approach may help the interdisciplinary team understand who is primarily responsible for care at any given time while understanding the dynamic nature of management of the high-risk patient.
Treatment of diabetic foot wounds in both the acute care setting as well as the longitudinal clinical setting is complex and by its very nature mandates a team approach. Team members frequently must work simultaneously on overlapping duties, rather than sequentially or in linearly oriented individual silos of care 
The Wagner classification system 
is a linear one that lacks true circles of dominance. This was followed by the University of Texas System 
, which augmented the Wagner categories by creating a matrix that allowed for simultaneous classification of depth, infection and ischemia.
We suggest that, in a similar fashion to wound classification, a flexible long-term management philosophy should be dynamic and conceptually inclusive. To accomplish this, we often think of three intersecting rings jockeying for dominance at any given time during the life of the patient and his or her limb. These rings of dominance, illustrated in Fig. 1
, involve tissue loss, ischemia, and infection.
Fig. 1. Three intersecting rings of dominance for flexible, long-term management. Once a patient has a wound or has healed a wound, one might consider this flexible approach to management and assessment. Where does this patient’s biggest problem lie? Infection? Ischemia? Tissue Loss? Combinations?
1. Tissue loss dominant
The problem being addressed in the patient at the time of evaluation is one primarily of wound healing. Therapy usually involves appropriate debridement and offloading along with a simple moisture-retentive dressing strategy. Once the wound heals, the care of the patient who is predominantly “tissue loss dominant” must focus on protection of the tissue via external (shoes, insoles, inflammation monitoring
) or internal (reconstructive surgical, physical therapy) means. Neuropathy (loss of protective sensation, motor deformity and autonomic neuropathy) is often the underlying trigger for wound development in patients with diabetes.
2. Ischemia dominant
The problem that must primarily be addressed to effect wound healing is one of ischemia. This involves appropriate vascular assessment and a strategy for either monitoring or intervention 
3. Infection dominant
The problem being addressed may be an infected wound or, in the case of a healed wound, cellulitis. Addressing this ring may involve surgical and medical therapy based on established criteria 
When a patient presents to our clinic, we conceptually categorize, stage and grade the severity of their problem in each of these rings at the initial and all follow-up encounters. We have found this rubric greatly assists us in our interdisciplinary discussions about what ring (or rings) might be most dominant and should therefore command the focus of our attention. It is important to realize that the relative dominance of each ring and its contribution to effecting limb salvage can change over time. An initially ischemia dominant presentation can change to a primarily wound dominant ring after successful revascularization. During follow-up, recurrence or non-healing may subsequently be due to recurrent ischemia requiring re-intervention or the development of an infection, requiring the limb salvage team to alter therapy and reprioritize the focus of care to one of the other rings.
We offer this conceptual strategy to all of our colleagues working in this field as an initial strategy to bring order to what, at times, might feel like a chaotic circus of competing consultations and care. If one cannot serve as lord of the rings, then one perhaps can be content with improving one’s abilities as clinical ringmaster alongside one’s colleagues and patients.