Necrotising fascitis

Question 1

What is necrotising fasciits?

Answer 1

life threatening infection that spreads along tissue planes

Question 2

What are the risk factors for necrotising fasciits?

Answer 2

Immune supression- DIABETES
                                 AIDS
                                 CANCER
BACTERIAL INTRO- IVDU
          HYPODERMIC THERAPEUTIC INJECTIONS
          INSECT BITES
          SKIN ABRASIONS
         ABDO/ PERINEAL SURGERY

OBESITY

Question 3

What is the prognosis of necrotising fascitis?

Answer 3

Mortality rate 32%

correlates with time to surgical intervention

Question 4

How is necrotising fasciits classified?

Answer 4

TYPE 1) POLYMICROBIAL- typical 4-5 organisms mix anaerobic and aerobic
most common 80-90%
seen in immunocompromised and post op surgery

TYPE 2) MONOMICROBIAL- group A beta haemolytic STREP most common organism
5%cases, seen in healthy patients in extremities

TYPE 3- Marine vibrio vulnificus- marine exposure

TYPE 4 - MRSA

Question 5

What do pt with necrotising fasciitis present with ?

Answer 5

early- localised abcess/cellulitis with rapid progression
         minimal swelling
         no trauma/ disclouration
Late- SEVERE PAIN
         HIGH FEVER CHILLS and RIGORS
        TACHYCARDIA

Question 6

What clinically do you find with necrotising fasciitis?

Answer 6

Skin BULLAE
SKIN DISCOLOURATION-ISCHAEMIC PATCHES
                    CUTANEOUS GANGRENE
SWELLING/OEDEMA
DERMAL INDURATION/ ERYTHERMA
SUBCUTANOUES EMPHYSEMA-gas producing organisms

Question 7

What is the definitive dx of necrotising fasciitis?

Answer 7

Biopsy but surgical intervention should dnot be delayed to obtain

Question 8

Do you know of any scoring system to aid dx of necrotising fasciitis?

Answer 8

LRINEC score
score > 6 positive predictive value 92% NF
CRP >150= 4 POINTS
WCC 25= 2 POINTS
HB     >13.5=0 POINTS
          11-13.5= 1 POINT
          141UMOL/L= 2 POINTS
GLUCOSE >10MMOL/L = 1 POINT

Question 9

What is the tx for necrotising fasciitis

Answer 9

SURGERY
EMERGENCY RADIAL DEBRIDEMENT WITH BORAD IV ANTIBIOTICS
op findings- liquefied subcutaneous fat, dishwater pus, muscle necrosis and venous thrombosis

technique- haemogynamic monitoring and systemic resuscitation critical
hyperbarbic O2 if ANAEROBIC ORGANISMS

AB- INTIALLY-PENCILLIN
CLINDAMYCIN
METRONIDAZOLE
an a AMINOGLYCOSIDE

Question 10

What definitive antibtiocs can be given?

Answer 10

Pencillin G for STREP or CLOSTRIDIUM
Impipenem for POLYMICROBIAL
add VANC if MRSA

Question 11

what are the indications for amputation?

Answer 11

Low threshold when life threatening