This letter is in reference to Williams RL. Cadexomer Iodine: An Effective Palliative Dressing in Chronic Critical Limb Ischemia. WOUNDS. 2009;21(1):15–28.
Studies performed on a limited number of demographically similar patients without a control arm or randomization may still provide useful clinical information when the results are carefully reviewed, scrutinized, and presented in an objective fashion.
One of the conclusions drawn from this limited number of patients (n = 11) is that “cadexomer iodine is an effective palliative dressing for wounds with CCLI.” Without a valid number of patients and an acceptable control, statements on autolytic debridement, anti-inflammatory effects, and the promotion of wound closure through granulation and epithelialization are, at best, assumptions. The author should also take care in making statements that the cadexomer iodine facilitates dry gangrene, a process that I would not want to see promoted by any product. I believe the intent was to state that the product promotes demarcation of viable from nonviable tissue although, even this assumption needs further investigation.
The limited number of patients reviewed is not as great a concern as the subjective conclusions and theories presented. The rationale for “cautious debridement” is justified,1 but does not support the conclusion that amputations that are delayed, may significantly improve quality of life for the affected individual. References are cited for the beneficial effects of decreasing bacteria and incidence of infection in ischemic wounds, however the data referenced is based on wounds associated with presumably acceptable blood flow. Data on the possibility of introducing infection and contributing to amputation through debridement would be desired in such a paper. I agree that while true gangrene or putrification of tissue may contribute to amputation and sepsis, the difference between a true gangrene and dry gangrene needs to be clarified both in appearance and definition. The term “dry gangrene” often is used to describe dry eschar on a wound surface, a material that is anything but putrifying.2 Evidence is needed to support the presence of high levels of bacteria in dry gangrene that may lead to bacterial dissemination, infection, and possible sepsis. There is also no evidence currently available that indicates dry eschar or dry necrotic tissue mitigates the inflammatory process. Neither is evidence available supporting conservative debridement as a means of preventing further gangrene or progressive infection.
The belief that preventing amputation will lead to a better quality of life is concerning. Implying that a limb with wounds and even osteomyelitis might allow for better function ignores the vast improvements made in prosthetics, which allow for excellent function and ambulation, thus improving the individual’s quality of life. Small areas of necrosis, such as dry necrosis of the digits, may be adequately addressed through self-amputation versus surgical intervention. Patients who are poor surgical candidates may suffer greater morbidity or mortality from a surgical intervention. When more extensive necrosis is present, numerous factors must be considered, particularly the existing quality of life. No information is presented on what the patient’s quality of life or mental status was during the conservative treatment period, nor is the eligibility of each patient for a surgical procedure discussed in detail.
In many instances, a below knee amputation may allow for rapid ambulation, decreased pain, and a return to an almost normal lifestyle while deferring amputation and keeping a patient non-weightbearing, which may decrease quality of life and prevent ambulation. Many unsupported assumptions that are presented may mislead readers into believing that it is best to delay amputations as long as possible. In cases where amputation is inevitable, as appears to be the case with some of the cohort patients, a thorough review of the patient’s medical status, medical history, and lifestyle should be considered before deciding whether conservative or surgical approaches are appropriate. Patients who are better served by amputation may require extensive patient and family education as well as counseling to assist with their final decision to proceed with amputation.
Additional treatment modalities, including the circulator boot, are mentioned and a detailed explanation of how these products may assist with wound closure associated with marginal blood flow is warranted. A brief review and discussion of additional adjunctive modalities including hydro-debridement, hyperbaric oxygen, and other devices assisting arterial flow, would provide an objective overview of the various conservative options available for patient care.
The topic of conservative debridement and deferment of amputations is welcomed in the medical literature, particularly in a society prone to amputating as a primary approach to treating the lower extremity with ischemic lesions. However, the topic should be presented in a balanced and scientific manner, avoiding trite terminology, exaggerated statements, and unsubstantiated assumptions. Rationale for choosing a conservative versus a surgical approach, the advantages and disadvantages of each choice, as well as indications and contraindications for each approach, are inadequately discussed in this manuscript.
Even when conservative debridement and care is in the individual’s best interest, clear algorithms and guidelines with supporting references would help both the clinician and patient in their treatment choice.
Gerit Mulder, DPM, MS
Director of Wound Treatment and Research Center
Professor of Surgery and Orthopedics
Department of Surgery/Division of Trauma
University of California San Diego
1. Barbul A. Wound Care Guidelines of the Wound Healing Society. Wound Repair Regen. 2006;14(6):645–711.
2. WordNet: A Lexical Database for the English Language. Dry gangrene. Available at: http://wordnetweb.princeton.edu/perl/webwn.