Use of Negative Pressure Wound Therapy after Endovascular Revascularization in a Patient with Diabetic Foot Syndrome Complicated by Sepsis

REPORT Abstract —We present a case report of a patient suffering from Diabetic Foot Syndrome (DFS) of ischemic etiology. The patient developed toe and dorsal foot tissue necrosis, underwent a revascularization procedure and subsequently amputation of the necrotic tissues. The patient was treated with vacuum therapy. During the hospitalization, despite microbial monitoring of the wound and use of wide spectrum antibiotics according to antimicrobial susceptibility testing (AST), a generalization of the infection occurred and septic shock symptoms followed what in the end resulted in high limb amputation.


I. INTRODUCTION
D IABETES, aside from obesity, arterial hypertension, and chronic obstructive pulmonary disease, is one of the most prevalent diseases.It is estimated that in Europe 2-5% of the general population suffers from diabetes.In some world regions, the disease has reached an epidemic status. 1 It often develops asymptomatically due to deep ischemia of the extremities and disturbance of pain sensation, caused by nervous system impairment.
Every week 100 people with DFS lose a foot due to complicated ulcerations and the frequency of amputations caused by non-healing ulcers or necrosis is 60-85%. 2,3 nternational Diabetes Federation (IDF) estimates that 382 million people suffer from diabetes all over the world, including 3 million in Poland alone.Every 6 seconds a person dies due to complications of diabetes. 3According to Polish Diabetic Association, Poland is in the group of countries performing the highest number of extremity amputations, and additionally 30,000 patients die annually due to diabetes. 4FS is the result of a poorly managed diabetes.We recognize neuropathic, vascular and mixed forms of DFS.According  to the Kings College Hospital in London, 62% of patients suffer from neuropathic DFS 13% from a vascular type and 25% from mixed type DFS.Symptoms of ischemic etiology DFS are rest pain especially during the night, localized in the distal part of the lower extremity.The pain decreases after lowering of the limb and increases with lower limb edema.On the other hand the neuropathic DFS is characterized by cold sensation, numbness, increased skin temperature, visibly engorged veins, muscle tremor, cramps and crushing sensation.In comparison to vascular DFS pain, this one is constant, disseminated, with episodes of massive aggravation.It escalates into allodynia and subsequently disappears after the total nervous disruption.All of those changes are steps that could be indicative of ongoing gangrene or skin ulceration process.The proper treatment protocol is supported by basic laboratory parameters, wound swab culture (in order to identify the main pathogen), as well as confirmation of infection duration and DFS etiology.[7][8][9][10][11][12][13] The efficacy of ulcerative changes treatment was evaluated in many previous publications.Those did not however include aspects of fulminant septic symptoms that often lead FRACO Publishing c b DOI: 10.18487/npwtj.v2i2.17 to amputation.In the case of mixed DFS, deep progressive limb ischemia is probable even in the absence of symptoms.This condition provides consequently a favorable environment for the growth of bacteria, what can then lead to progressive infection, sepsis and often the death of the patient.5][16] In this paper, we present a complex case of combination therapy, in which we failed to rescue the patient's limb.

II. CASE REPORT
A 60-year-old patient was admitted to the hospital emergency department due to necrotic lesions of the dorsal surface of the toes as well as dorsal-and the lateral side of the foot.The patient suffered from type II diabetes for an unspecified time period.Outpatient medical treatment consisted of the topical application of a broad spectrum antibiotic ointment.About three weeks after the first symptoms appeared, the patient was admitted to the hospital.Necrotic lesions were defined as stage IV according to the classification of Wagner.Patient concomitantly suffered from hypertension and smoked 30 cigarettes per day for 40 years, leading a sedentary lifestyle.His Body Mass Index was about 32.Pulse was palpable over the femoral arteries, poorly palpable over the right popliteal artery, and not palpable on the arteries of the foot.Ankle Brachial Index was 0.8.Patient was diagnosed with ischemic DFS with dry ulcer with necrosis, swelling and inflammation of the forefoot and midfoot, which did not extend to II and IV toes.This resulted in swelling and excessive calor of the entire foot.See figure 1.
After hospital admission, we ordered microbiological wound tests, which indicated Pseudomonas aeruginosa infection.Intravenous targeted antibiotic therapy was initiated: Augmentin (at a dose of 2.4 g per day) and Gentamicin (at a dose of 160 mg per day).
In less than a few hours after admission to the hospital, we were forced to order an urgent angiography -numerous major vascular constriction of the lower limb became apparent.The right popliteal artery in the P2 segment was constricted in 70%, the tibial artery in 80%, and sagittal artery -90%.These changes were reversed after the application of percutaneous balloon angioplasty of all above-mentioned arteries.Additionally, 75 mg of clopidogrel daily was administered.We were able to achieve a significant improvement in peripheral circulation, pulse over peripheral arteries, as well as improvement of peripheral distal limb's perfusion.See figure 2.
We then performed a rapid debridement of the ulcer by removing of necrotic and purulent material within the healthy tissues.VAC dressings were applied on such prepared wound bed to remove excessive secretions as well as improve blood circulation and reduce swelling.Dressing changes were performed every 2-3 days.See figure 3.
During second dressing change, additional debridement was performed.A noticeably better perfusion of the distal limb tissues was observed.See figure 4.
During third dressing change (nine days since admission) we diagnosed necrosis of the toes III-V.We decided to   amputate these with wide debridement of the ischemic tissues.See figure 5.
The eleventh day after admission to the hospital, (between the third and fourth dressing change) VAC dressing decompression occurred, which resulted in the accumulation of pus in the deep wound layers.Inadequate resealing of the dressing, conducted by a nurse team, without the doctor's supervision, probably allowed for the rapid development of bacterial outgrowth.The event took place during the weekend, at the time the patient was in an unconditioned room with high interior temperature.
Over the next three days the edema and inflammatory infiltration progressed.Along with these changes hectic fever of up to 40.2 • C, tachypnoea, and fatigue at rest occurred.Laboratory work-up demonstrated an increase in the number of leukocytes to about 18,000 / mL and high C-reactive protein (CRP) level (from 50 mg/L to about 230 mg/L within 3 days).Procalcitonin has reached a level of >400 ng/mL.4 days after the dressing decompression, consciousness, and cognitive disorders occurred.All these factors including the patient's clinical state pointed to the emergence of a generalized infection and septic shock symptoms.In order to save the patient's life, we were forced to perform a high amputation of the lower limb.See figure 6.

III. DISCUSSION
Undiagnosed or poorly managed diabetes can lead to the development of ischemia, atherosclerosis, or neurological disorders.One of the chronic complications of diabetes is DFS, which affects not only the health of the patient, but it can also threaten his life.[19] During hospitalization, the patient was treated with targeted antibiotics according to AST results.We re-vascularized ischemic tissues, eliminated necrosis out of the wound bed and used vacuum dressings which we changed every 2-3 days.We also evaluated the possibility of wound closure using skin grafts or dermal flap reposition with simultaneous treatment of concomitant diseases which we eventually abandoned.
2] Statistically, we most often deal with wound colonization by Pseudomonas aeruginosa (in 21.43% of symptomatic patients) and Staphylococcus aureus (17.86% of respondents). 4Thus, it is difficult to choose the right antibiotic, without knowing the type of pathogen present in the wound.
In the described case, prolonged prehospital treatment based on broad spectrum antibiotics in insufficient doses was incorrect, which could have favored the accumulation of necrosis.The literature suggests that the risk of amputation increases with the duration of the disease and with each day of conservative treatment. 23n the case of DFS, changes occur in tunica media, leading to calcification, which causes narrowing of the lumen or even total obstruction of the artery. 24Balloon angioplasty of the main lower limb arteries improves the blood circulation and nutrient supply to the wound, what reduces the time of treatment.It reduces the risk of wound recurrence while  endovascular treatment is often the last chance to save the limb from amputation. 3,14,18,24 Enovascular treatment begins to gain an important role in the treatment of DFS and should be applied in combination with surgical approach. 25,26  the above case we were dealing with a mixed type of DFS, with a significantly increased risk of sepsis.Ulcers with a small outer diameter often may mask more serious lesions in the deeper tissues that would require extensive radical debridement.The mean treatment duration of DFS ulcers takes approximately 3-5 months.Implementation of the vacuum dressings changed every 2-3 days, combined with surgical wound debridement has reduced this time to approximately 1 month. 17,27 achal et al. estimated that the average treatment time using this method is reduced to 19 days. 14ne of the principles of this approach is the close cooperation of all medical staff members, both doctors as well as the nursing staff.The well-trained medical team should understand the phenomena taking place in the ischemic limb and respond quickly in case of vacuum dressing leaks. 13,28 eaving the wound covered by a sealing film in an unconditioned room where the temperature exceeds 25 • C will inevitably lead to a rapid outgrowth of bacteria, which can turn into a rapidly progressive sepsis leading to a septic shock.
There is general agreement that the use of VAC dressings improved blood circulation and promotes wound granulation process.30] It is estimated that about 750,000 people worldwide die each year from complications of severe sepsis or septic shock.Mortality despite the introduction of the latest standards, ranges from 30-60% of patients.Gierek et al. showed, that in the group of 646 intensive care unit (ICU) patients (during 2008-2009) 7.0% were diagnosed with severe sepsis (3 patients) or septic shock (42 patients) and 29 patients died (57.7%). 31In Poland, the incidence and mortality of sepsis are significant.
According to the Polish Sepsis Working Group's study, the prevalence of severe sepsis is approximately 14.6% of patients treated in the ICUs while the diagnosis of septic shock could be made in 6% of those patients. 22People who die due to sepsis, are often affected by concomitant diseases: cardiovascular disease, atrial fibrillation, coronary heart disease, hypertension, diseases of the pancreas, chronic renal failure or diabetes. 31n the pathological evolution of septic shock, the symptoms of sepsis are accompanied by hypotension with impaired tissue perfusion. 22In our patient, about 4 days after vacuum dressing decompression CRP levels, procalcitonin levels and leukocyte numbers significantly increased.We observed respiratory as well as consciousness disorders and drop in blood pressure.Our decision to perform lower limb amputation was due to the ongoing significant deterioration of the clinical condition, and occurrence of the septic shock indicators.By removing the source of infection, clinical state improvement was achieved. 32,33 ring the Open Diabetes Leadership Forum, which was held in Beijing in 2009, Kofi Annan said: "Throughout the world, the threat of diabetes is ignored and under-funded.Fighting diabetes must be a priority.The problem is so serious that we all need to get involved if we want to prevent the epidemic wave".We agree with these words.Fast action, the right management and adequate training of the medical team are the most important aspects affecting the proper treatment of DFS.

Figure 1 .
Figure 1.The mid-foot ulcer before first surgical intervention

Figure 2 .
Figure 2. Angiography: arrows show a marked arterial constriction, which was resolved by percutaneous balloon angioplasty.Negligible flow to peripheral arteries is visible.

Figure 3 .
Figure 3.The first fitting of the vacuum dressing, removal of all possibly necrotic tissues.

Figure 4 .
Figure 4.The second debridement of necrotic lesions on the sixth day of admission.Significant improvement in limb blood flow.

Figure 5 .
Figure 5.The necessity of II to V toes amputation occurred.Proper blood circulation in the limb visible (b).

Figure 6 .
Figure 6.Significant deterioration in the blood supply to the limb (a).One of the stages of limb amputation (b).