醫學筆記匯整 ED Notes

Necrotizing fasciilitis 和 Cellutitis 鑑別
以下症狀要想到necrotizing fasciilitis

 - Fever, Toxicitcy, Vital sign 很差
 - Soft tissue involvement with severe pain (out of proportion)
 - Crepitus on PE
 - Rapid progression of clinical manifestations
 - Elevated serum CK level 
 - Hemorragic bullae is not skin deep
 - Subcutaneous emphysema is only in 17% - 30% of necrotizing fasciitis

 

Type I necrotizing fasciitis
Mixed infection caused by Aerobic + Anaerobic bacteria
Risk factors include DM, peripheral vascular disease, immune compromise, recent surgery. 
Necrotizing infection of the male perineum = Fournier's gangrene

Type II necrotizing fasciitis
Monomicrobial
Typically caused by group A Streptococcus or other beta-hemolytic streptococci
either alone or in combination with other pathogens, most commonly S. aureus
Predisposing factors : history of skin injury
 

- Ultrasound is more useful and ubiquitous in ER

Treatment
 - Surgical emergency + Anti + hemodynamic support
 - Use of antibiotic therapy without debridement is associated with a mortality rate approaching 100 percent
 - Goal of operative management -->
   Aggressive debridement of all necrotic tissue until healthy, viable (bleeding) tissue is reached

Anti choice 
 Broad-spectrum : cover gram-positive, gram-negative, anaerobic organisms
 --> Carbapenem or beta-lactam-beta-lactamase inhibitor + Clindamycin 600 to 900 mg IV Q8H (in adults)
      + Vancomycin, daptomycin, or linezolid

** Clindamycin 有 antitoxin effects  (against toxin-elaborating strains of streptococci and staphylococci)
** 特殊 Exposure history --> trauma in sea water --> V. vulnificus --> Doxicyclin + 3代 cepha
 

Outcome
Mortality rate : 
20 percent in type I necrotizing fasciitis
14 - 34 percent in type II necrotizing fasciitis (in which streptococcal toxic shock syndrome is commonly associated with mortality) 

Summary
 - Deadly and rapid extensively progressing disease
 - Could have legal problems
 - Identify independent risk factors and the factors for mortality
 - Hemorrhagic bullae
 - Liver cirrhosis patient, especially Child C
 - Immunocompromised, DM, Old age, HF
 - Ideal medical document record and stay with the families before any medical decision making