Approach Considerations
Once the diagnosis of necrotizing fasciitis is confirmed, initiate treatment without delay. [27, 80] Because of the complexity of this disease, a team approach is best (see Consultations). Hemodynamic parameters should be closely monitored, and aggressive resuscitation initiated immediately if needed to maintain hemodynamic stability.
Because necrotizing fasciitis is a surgical emergency, the patient should be admitted immediately to a surgical intensive care unit in a setting such as a regional burn center or trauma center, where the surgical staff is skilled in performing extensive debridement and reconstructive surgery. Such regional burn centers are ideal for the care of these patients because they also have hyperbaric oxygen facilities.
A regimen of surgical debridement is continued until tissue necrosis ceases and the growth of fresh viable tissue is observed. If a limb or organ is involved, amputation may be necessary because of irreversible necrosis and gangrene or because of overwhelming toxicity, which occasionally occurs. Prompt surgery ensures a higher likelihood of survival.
Antibiotic therapy is a key consideration. Possible regimens include a combination of penicillin G and an aminoglycoside (if renal function permits), as well as clindamycin (to cover streptococci, staphylococci, gram-negative bacilli, and anaerobes).
While the literature appears to support the use of hyperbaric oxygen as an adjunctive treatment measure in patients with necrotizing fasciitis, transfer to a hospital equipped with a hyperbaric oxygen chamber should not delay emergency surgical intervention.
In a study of six patients with necrotizing fasciitis, Crew et al found that flow-through instillation with saline containing pure 0.01% hypochlorous acid (with no sodium hypochlorite impurity) may weaken bacterial toxins and the toxins released from damaged cells, as well as mitigate the immune dysfunction they cause. [81]
The following related guidelines have been published:
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Society of Critical Care Medicine -Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock: 2008
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Infectious Diseases Society of America -Practice guidelines for the diagnosis and management of skin and soft-tissue infections
Surgical Debridement
Surgery is the primary treatment for necrotizing fasciitis. .Surgeons must be consulted early in the care of these patients, as early and aggressive surgical debridement of necrotic tissue can be life-saving. [17, 71, 82, 83, 84, 80] In addition, early surgical treatment may minimize tissue loss, eliminating the need for amputation of the infected extremity. [85, 86]
The authors recommend wide, extensive debridement of all tissues that can be easily elevated off the fascia with gentle pressure. Wide debridement of all necrotic and poorly perfused tissues is associated with more rapid clinical improvement.
Controversy exists regarding how much tissue should be initially excised because the skin may often appear normal. Andreasen et al examined the normal-appearing tissues microscopically and reported that the tissues had extensive early vascular thrombosis as well as vasculitis. [37] Their findings indicate that these tissues, though they have a normal appearance, have a high potential for full-thickness loss.
After the initial debridement, the wound must be carefully examined. Hemodynamic instability is usually present after surgery, and it may cause progressive skin necrosis. After debridement, the patient may return as often as necessary for further surgical debridement. The anesthesiologist is an important member of the operative team because continued resuscitative efforts are undertaken during the operative procedure.
The surgical regimen can be summarized as follows:
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Surgical incisions should be deep and extend beyond the areas of necrosis until viable tissue is reached
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The entire necrotic area should be excised
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The wound should be well irrigated
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Hemostasis should be maintained, and the wound should be kept open
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Surgical debridement and evaluations should be repeated almost on a daily basis
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The wound should be inspected in the operating room
Double gloving
During surgery, all operating room personnel should wear a powder-free double-glove hole indication system (ie, including an underglove with distinct color that becomes apparent when the outer glove is punctured in the presence of fluid). This protects the staff as well as the patient from exposure to potentially deadly blood-borne viral infections. [87]
The US Food and Drug Administration (FDA) only requires that the leakage rate of sterile surgical gloves does not exceed 1.5%. This high frequency of glove holes is an invitation to the spread of deadly blood-borne infections between operating room personnel and the patient.
Cornstarch in wounds has been well documented to potentiate the development of infection. Using powder-free gloves reduces this potentially serious complication. In addition, the cornstarch on latex gloves can carry the latex antigen and precipitate anaphylactic reactions in individuals who are allergic to latex. [88]
Dressings
Following each debridement of the necrotic tissue, daily antibiotic dressings are recommended. [89] Silver sulfadiazine (Silvadene) remains the most popular antimicrobial cream. This agent has broad-spectrum antibacterial activity and is associated with relatively few complications in these wounds.
The current formulation of silver sulfadiazine contains a lipid-soluble carrier, polypropylene glycol, which has certain disadvantages, including pseudoeschar formation. When this antibacterial agent is formulated with poloxamer 188, the silver sulfadiazine can be washed easily from the wound because of its water solubility, making dressing changes considerably more comfortable.
If the patient is allergic to sulfa, alternative agents include Polysporin, Bacitracin, and Bactroban. While these agents are relatively inexpensive, they may induce allergies.
Mafenide is an alternate agent that penetrates eschar more effectively than silver sulfadiazine. Consequently, it is frequently used on infected wounds that do not respond to silver sulfadiazine. Use mafenide with caution because it can induce metabolic acidosis.
The Acticoat brand of barrier dressings provides the beneficial antimicrobial properties of the silver ion by coating the dressing material with a thin, soluble silver film. This dressing appears to maintain antibacterial levels of silver ions in the wound for up to 5 days. Because Acticoat can remain on the wound for up to 5 days, the patient is spared the pain and expense associated with the dressing changes. Additional studies are now under way to determine the ultimate benefit of this product.
Soft-tissue reconstruction
Once all of the affected tissues have been debrided, soft tissue reconstruction can be considered. In the authors’ experience, this may take at least 2 debridements. When the debridement involves relatively small (< 25%) body surface areas, skin grafts and flaps can provide coverage. When donor-site availability is limited, alternatives to standard skin graft construction must be considered, including Integra artificial skin (Integra Life Sciences, Plainsboro, NJ) and AlloDerm (LifeCell Corporation, Blanchburg, NJ). [90, 91]
Antimicrobial Therapy
Empiric antibiotics should be started immediately. Initial antimicrobial therapy should be broad-based, to cover aerobic gram-positive and gram-negative organisms and anaerobes. A foul smell in the lesion strongly suggests the presence of anaerobic organisms. The maximum doses of the antibiotics should be used, with consideration of the patient's weight and liver and renal status.
Antibiotic therapy is a key consideration. Possible regimens include a combination of penicillin G and an aminoglycoside (if renal function permits), as well as clindamycin (to cover streptococci, staphylococci, gram-negative bacilli, and anaerobes).
A more specifically targeted antibiotic regimen may be begun after the results of initial gram-stained smear, culture, and sensitivities are available.
Although some necrotizing infections may still be susceptible to penicillin, clindamycin is the treatment of choice for necrotizing infections, for the following reasons [70] :
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Subinhibitory concentrations of clindamycin facilitate the phagocytosis of GABS [61]
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Clindamycin reduces the synthesis of penicillin-binding protein, which, in addition to being a target for penicillin, is also an enzyme involved in cell wall synthesis and degradation [93]
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Clindamycin has a longer postantibiotic effect than β-lactins such as penicillin [95]
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Clindamycin suppresses lipopolysaccharide-induced mononuclear synthesis of tumor necrosis factor-α (TNF-α) [96]
Consequently, the success of clindamycin also may be related to its ability to modulate the immune response. [97]
Broad-spectrum beta-lactam drugs such as imipenem cover aerobes, including Pseudomonas species. Ampicillin sulbactam also has broad-spectrum coverage, but it does not cover Pseudomonas species; however, necrotizing fasciitis caused by Pseudomonas aeruginosa is unusual. [98]
If staphylococci or gram-negative rods are involved, vancomycin and other antibiotics to treat gram-negative organisms other than aminoglycosides may be required. The use of vancomycin to treat methicillin-resistant Staphylococcus aureus (MRSA) may depend on the clinical situation. For example, use may depend on whether a nasocranial infection is present, or it may need to be avoided in patients who are likely to be carriers of MRSA (eg, those with diabetes, those who use illicit drugs, those undergoing hemodialysis).
For more information on antimicrobial therapy, see the Medscape Reference articles Necrotizing Fasciitis Empiric Therapy and Necrotizing Fasciitis Organism-Specific Therapy
Fluid, Nutritional Support, IVIG
Because of persistent hypotension and diffuse capillary leak, massive amounts of intravenous fluids may be necessary after the patient is admitted to the hospital. Nutritional support is also an integral part of treatment for patients with necrotizing fasciitis. This supplementation should be initiated as soon as hemodynamic stability is achieved. Enteral feeding should be established as soon as possible to offset the catabolism associated with large open wounds.
Successful use of intravenous immunoglobulin (IVIG) has been reported in the treatment of streptococcal toxic shock syndrome (STSS). [99, 100] In a multicenter, randomized, double-blind, placebo-controlled trial of the efficacy and safety of high-dose polyspecific IVIG as adjunctive therapy in 21 patients with soft-tissue STSS, mortality at 28 days was 3.6-fold higher in the placebo group. [101]
Norrby-Teglund et al successfully used high-dose polyspecific IVIG, along with antimicrobials and a conservative surgical approach, in 7 patients with severe group A streptococcal soft tissue infections. [102] However, Sarani et al indicate that this therapy has not been approved by the FDA for the treatment of necrotizing fasciitis. [103]
Hyperbaric Oxygen Therapy
Once other modalities, including surgical debridement and antibiotic administration, have been used, hyperbaric oxygen therapy (HBOT) may be considered, if available. [104, 56, 105] The literature suggests that HBOT can reduce mortality when used as part of an aggressive treatment regimen for necrotizing fasciitis. [106, 61, 107, 70, 108]
A retrospective, single-center study by Mladenov et al, for example, found that the survival rate for patients with necrotizing fasciitis who underwent HBOT was higher than that for individuals who, despite having clinical indications for HBOT, were ineligible for the treatment owing to contraindications (73.5% vs 36.4%, respectively). The survival rate of the patients who received HBOT was comparable to that of persons with necrotizing fasciitis who did not require the therapy (75.5%). [109]
Well-controlled, randomized, clinical trials demonstrating a statistically significant benefit of HBOT are lacking, however, and consequently its use as an adjunctive therapy for necrotizing fasciitis remains controversial. [110, 111, 112] Transfer to a hospital equipped with HBOT should not delay emergency surgical intervention.
Consultations
A team approach is the best method of treating this complicated disorder. Team members should include the following:
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Surgeon
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Infectious disease specialist
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Pathologist
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Microbiologist
Depending on the infection site, the team may also include a urologist; a specialist in plastic surgery; or an ear, nose, and throat surgeon in cases of infections of the cervical area. [113]
The specialists and subspecialists involved should discuss the patient's condition and determine a comprehensive plan of treatment.
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Left upper extremity shows necrotizing fasciitis in an individual who used illicit drugs. Cultures grew Streptococcus milleri and anaerobes (Prevotella species). Patient would grease, or lick, the needle before injection.
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Necrotizing fasciitis at a possible site of insulin injection in the left upper part of the thigh in a 50-year-old obese woman with diabetes.
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Photomicrograph of Fournier gangrene (necrotizing fasciitis), oil immersion at 1000X magnification. Note the acute inflammatory cells in the necrotic tissue. Bacteria are located in the haziness of their cytoplasm. Courtesy of Billie Fife, MD, and Thomas A. Santora, MD.
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Left lower extremity in a 56-year-old patient with alcoholism who was found comatose after binge drinking. Surgical drainage was performed to treat the pyomyositis-related, large, non–foul-smelling (sweetish) bullae. Gram staining showed the presence of gram-positive rods. Cultures revealed Clostridium perfringens. The diagnosis was clostridial myonecrosis.
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Sixty-year-old woman who had undergone postvaginal hysterectomy and repair of a rectal prolapse has a massive perineal ulceration with foul-smelling discharge. Cultures revealed Escherichia coli and Bacteroides fragilis. The diagnosis was perineal gangrene.
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Necrotizing fascitis of entire thoracolumbar posterior area in 20-year-old patient with chronic myelogenous leukemia and neutropenia (WBC count, 680/uL). Cultures revealed gram-negative Pseudomonas species and Bacteroides fragilis.
