Surgical Site Infections :Surgical Site Infections By Doctor Saleem


surgical site infections :surgical site infections 3rd most common nosocomial infection 14-16% Most common nosocomial infection among surgery patients 38% 2/3 incisional 1/3 organ


Important Definitions :Important Definitions Colonization Bacteria present in a wound with no signs or symptoms of systemic inflammation Usually less than 105 cfu/mL Contamination Transient exposure of a wound to bacteria Varying concentrations of bacteria possible Time of exposure suggested to be < 6 hours SSI prophylaxis best strategy


Contd; :Contd; Infection Systemic and local signs of inflammation Bacterial counts ≥ 105 cfu/mL Purulent versus nonpurulent Surgical wound infection is SSI


Criteria for defining SSIs :Criteria for defining SSIs


Further Classification :Further Classification Etiology a) Primary The wound is the primary site of infection b)Secondary Infection arises following a complication that is not directly related to wound


Contd; :Contd; Time a) Early Infection presents within 30 days of procedure b) Intermediate Occurs between one and three months c) Late Presents more than three months after surgery


Contd; :Contd; Severity a) Minor Wound infection is described as minor when there is discharge without cellulitis or deep tissue destruction b) major When there is pus discharge with tissue breakdown , Partial or total dehiscence of the deep fascial layers of wound or if systemic illness is present.


Wound assesment :Wound assesment For surgical wound assesment several scoring systems are employed especially a) Asepsis scoring b) Southampton wound assessment scale These enable surgical wound healing to be graded according to specific criteria, usually giving a numerical value, thus providing more objective assessment of wound.


Microbiology :Microbiology


Slide 17:Lactobacilli Streptococci Lactobacilli Enterobacteriaceae Aerobic + Anaerobic Microbial Populations


Pathogenesis :Pathogenesis Virulence Bacterial dose Impaired host resistance


Risk factors :Risk factors Patient factors Diabetes Obesity Nicotine use Steroid use Malnutrition Hospital stay  Nares colonization with S. aureus Transfusion


Slide 20:Diabetes  Controversial  Patients underwent CABG @ Increasing levels of HbA1c and SSI rates @ Increased glucose levels (>200 mg/dL) Nicotine use  Delays primary wound healing  Increase the risk of SSI Steroid use  Controversial


Slide 22:Malnutrition  Theoretical arguments: increase the SSI risk  Two randomized clinical trials: preoperative “nutritional therapy” did not reduce incisional and organ/space SSI risk. Prolonged preoperative hospital stay Preoperative nares colonization with S. aureus Mupirocin ointment: Controversial Perioperative transfusion  No scientific basis


Preop factors :Preop factors Preoperative antiseptic showering Preoperative hair removal Patient skin preparation in the operating room Preoperative hand/forearm antisepsis Antimicrobial prophylaxis


Slide 24:Preoperative antiseptic showering  Decreases skin microbial colony counts  No evidance of benefit to reduce SSI rates Preoperative hair removal  Shaving: @ immediately before the operation: SSI rates 3.1% @ shaving within 24 hours preoperatively: 7.1% @ having performed >24 hours: SSI rate > 20%.  Depilatories: @ lower SSI risk than shaving or clipping @ hypersensitivity reactions


Slide 25:Patient skin preparation in the operating room  Most common used: Alcohol solutions Chlorhexidine gluconate Iodophors Preoperative hand/forearm antisepsis


Prophylactic antibiotics :Prophylactic antibiotics Class 1 = Clean Class 2 = Clean contaminated Class 3 = Contaminated Class 4 = Dirty infected Prophylactic antibiotics indicated Therapeutic antibiotics


Slide 28:Once the incision is made, antibiotic delivery to the wound is impaired. Must give before incision!


Operative characteristics :Operative characteristics Operating room environment Surgical attire and drapes Asepsis and surgical technique


Slide 31:Operating room environment Ventilation @ Positive pressure with respect to corridors and adjacent areas Environmental surfaces @ Rarely implicated as the sources of pathogens important in the development of SSIs. @ Important to perform routine cleaning of these surfaces  Conventional sterilization of surgical instruments @ Inadequate sterilization of surgical instruments has resulted in SSI outbreaks


Slide 32:Surgical attire and drapes  The use of barriers: @ patient: minimize exposure to the skin, mucous membranes, or hair of surgical team members @ surgical team members: protect from exposure to blood and bloodborne pathogens. Asepsis and surgical technique  Rigorous adherence to the principles of asepsis by all scrubbed personnel  Excellent surgical technique: reduce the risk of SSI.  Drains: increase incisional SSI risk.


Postoperative issues :Postoperative issues Incision care  The type of postoperative incision care @ closed primarily: the incision is usually covered with a sterile dressing for 24 to 48 hours. @ left open to be closed later: the incision is packed with a sterile dressing. @ left open to heal by second intention: packed with sterile moist gauze and covered with a sterile dressing.


Slide 34:Treatment surgical site infection  Efflux of purulent material and pus  Fascia is intact: debridement Irrigated with N/S and packed to its base with saline-moistened gauze  Fascia separated: drainage or reoperation Most SSIs: healing by secondary intention


Slide 35:Discharge planning  The intent of discharge planning: maintain integrity of the healing incision, educate the patient about the signs and symptoms of infection, advise the patient about whom to contact to report any problems.


Slide 36:Thankyou