Wound Healing in Forefoot Amputations: The Predictive Value of Toe Pressure Michael J. Vitti, MD, David V. Robinson, BA, Martin Hauer-Jensen, MD, Bernard W. Thompson, MD, Timothy J. Ranval, MD, Gary Barone, MD, Robert W. Barnes, MD, and John F. Eidt, MD, Little Rock, Arkansas A retrospective study of 136 men undergoing forefoot amputation was done to test the hypothesis that preoperative toe pressure ('l'P) could predict the likelihood of wound healing. Demographic data included age, smoking history, diabetes mellitus (DM), hypertension, hyperlipidemia, and coronary artery disease. Clinical data included infection, preoperative arterial Doppler data, TP, wound disposition, concomitant revascularization (REV), and healing outcome. Among diabetics, no primary amputation healed with a preoperative TP <38 mm Hg. Among REV diabetics, no healing occurred with a TP <40 mm Hg after bypass, but no failures occurred either with a TP >68 mm Hg or an increase in TP ->30 mm Hg after bypass. Nondiabetic patients exhibited no threshold TP values. Univariate analysis revealed that DM and REV were significantly different in the healed (N = 83) vs. nonhealed (N = 53) popula- tions (p = 0.027 and 0.034). In healed patients, mean TP (71.8 --_ 3.5 mm Hg SEM) was significantly higher than in nonhealed patients (45.1 _+ 4.3 mm Hg SEM, p = 0.000). Logistic regression analysis identified age > 60 years (p = 0.03), DM (p = 0.003), preoperative TP (p < 0.001), and REV (p < 0.001) as significant independent predictors of forefoot amputation healing. Healing probability was calculated and plotted vs. TP for subpopulations based on age, DM, and REV status for both primary forefoot amputation and amputation concomitant with bypass. In this study population, therefore, preoperative TP appeared to be a useful clinical tool for predicting the healing potential of both primary forefoot amputations and amputations plus concomitant bypass for any given patient. (Ann Vasc Surg 1994;8:99-106.) In the treatment of gangrene or severe infection confined to the toes or distal forefoot, a successful forefoot amputation allows the patient to main- tain bipedal gait without the need for a prosthe- sis. Forefoot amputations, however, are notori- ously tenuous, with a documented healing failure rate of 30% to 45%. 17 Therefore a distal amputa- tion to maximize rehabilitation potential must be From the Department of Surgery, University of Arkansas for Medical Sciences, and John L. McClellan VA Medical Center, Little Rock, Ark. Presented at the Eighteenth Annual Meeting of the Periph- eral Vascular Surgery Society, Washington, D.C., June 6, 1993. Reprint requests: Michael J. Vitti, MD, Department of Vascular Surgery, 4301 West Markham St., Slot 520, Little Rock, AK 72205. weighed against the morbidity and cost resulting from the prolonged healing trials and reopera- tions that accompany healing failure. *'s Toe pressure (TP) measured by photoplethys- mography (PPG) has been reported to be superior to systolic ankle/brachial pressure (ABP) in its correlation with forefoot healing. 9 However, stud- ies have been unable to identify either a consis- tent TP threshold that guarantees healing or a lower limit TP below which healing failure is inevitable.* As a result, no systematic approach is available to predict the likelihood of forefoot am- putation healing preoperatively in any given pa- tient using TP. This study Was undertaken to test the hypoth- *References 3, 7, 8, 10, ll. 99