Surgical site infection Necritizing fasciculitis

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What is “Necrotizing   fasciitis”?  What is a Swan –Gang  line ??

 Necortizing fasciitis is a serious infection of the muscle and fascia  usually caused  by multiple organisms or anaerobes. It can   involve    surgical incision sites, infective wound, and traumatic injury or rarely Group A streptococci only. Sometimes it may cause a septic shock like syndrome if severe.

Severe Surgical site Infection( SSI)  may laed to    Septic shock and sometimes cause  Necrotizing   fasciitis. The septic shock    may result from severe surgical site infections(not uncommon in criminal septic abortion, Rupture uterus, Obst labour in farvoff rural places , hill ares)  . This Septic shock may also result in immunocompromised women specially  who are on long term steroids and if operation was contemplated in a suboptimal Operating theatre with poor sterility. Group  A  streptococci  toxic  shock syndrome is a rapidly progressing  infection which may occur at the episiotomy or cesarean delivery  incision  and very rarely this may cause shock even . Such shock was common in septic abortion 4- 5 decades back and was associated with condition of circulatory insufficiency where   tissue perfusion needs are not met. Septic shock usually leads to circulatory insufficiency commonly caused endotoxins released by gram negative organisms.

 How to treat : How such  a near moribund condition  was treated earlier ?  There were minimum no of antibiotics and knowledge of electrolyte imbalacec was at infancy. Customarily nowadays such pts are treated at ICU or HDU bit these facilities were nonexistent when we were students in the decades of sixties. The management of septic  shock  includes copious  intravenous fluids with close monitoring  of urine output   and blood pressure. At times   invasive   hemodynamic monitoring   with a central   venous catheter   or Swan –Gang line is   needed. Intravenous   antibiotics should be broad spectrum to  include penicillin gentamicin,  and metronidazole    or other  anaerobic agent,   and dopamine or doubt amine are  sometimes required    when fluids   alone are  insufficient   to maintain the   blood pressure. Addressing the underlying etiology   of the septic shock   is important. When dealing with an aggressive wound infection immediate surgical   debridement, sometimes   very radical or wide excisional   procedures, is warranted . Necrotic   and infected tissue  must be  removed , and sometimes   requires   multiple surgeries  . Monitoring   of blood pressure    heart  ratio oxygen   saturation, urine   output, and   neutral status  is important . Once the patient is stabilized , treating   the underlying   cause typically  leads to resolution. Septic shock   initially  presents ad decreased  urine output   and if untreated , proceeds  to ischemia of vital organs   and death.

The pathophysiology  of septic shock is vaso dilation   usually  due to endo toxins, although  at times , such  as with Staphylococcus   aureus  exo toxins can be    causative. The   vaso dilation leads  to hypotension, and is treated   with IV  fluids. If the  IV  fluids  are insufficient  to produce   a correction in hypotension, then   vasoconstrictors   are indicated , such as   dopamine. Late  in the course   of septic  shock, cardiac   dysfunction   can occur   ; however,   at this  stage, the    patient    is typically  in a near   terminal   condition.

 Gas in the muscle  or  fascia  is indicative of  necrotizing   fasciitis,  likely due to  a  clostridial  species. Induration   and redness  of the surgical wound is suggestive  of a superficial wound   infection , in which    the skin  and subcutaneous   tissue   is infected. This is a superficial surgical   site infection, and needs to be  opened. The   superficial   wound infection  is not   as life threatening   as when a deep  surgical  site infection occurs.

Intravenous isotonic fluids  are the initial  treatment   of choice  for septic  shock. The  cornerstones  of therapy  include removing   the nidus  of infection antibiotic , therapy   and support  and the blood pressure. Plasma pheresis is not a major   part of the treatment of septic shock.

The  cornerstones of treatment  of septic shock include  aggressive   intravenous  fluids , source  control  antibiotic  therapy and   monitoring   perfusion   and organ  function.

Source control in septic  shock means   removing  the etiology of the infection.

The  sunburn   like rash and / or  desquamation is   typical for  5  aureus  infections,

The initial    antibiotic therapy  for serious S  aureus   infections  is generally  intravenous    nafcillin or methicillin unless   methicillin  resistance   is suspected in  which case   vanocomycin is used.

Hypotension   that persists   despite   intravenous  isotonic fluid   replacement   generally requires  pressor support   such as with  intravenous   infusion of dopamine.