1、外科傷口及手術室之感染管制Public Health Importance of Surgical Site Infections In U.S.,40 million inpatient surgical procedures each year;2-5%complicated by surgical site infection SSIs second most common nosocomial infection(24%of all nosocomial infections)Prolong hospital stay by 7.4 days Cost$400-$2,600 per i
2、nfection(TOTAL:$130-$845 million/year)SSI level classification Incisional SSI -Superficial incisional=skin andsubcutaneous tissue -Deep incisional=involving deeper soft tissue Organ/Space SSI -Involve any part of the anatomy(organsand spaces),other than the incision,opened or manipulated during oper
3、ationsCDC Definition of Surgical Site InfectionsCross Section of Abdominal Wall Depicting CDC SSI ClassificationsSource of SSI Pathogens Endogenous flora of the patient Operating theater environment Hospital personnel(MDs/RNs/staff)Seeding of the operative site from distant focus of infection(prosth
4、etic device,implants)Microbiology of SSIsStaphylococcusaureus17%Coagulase neg.staphylococci12%Escherichiacoli10%Enterococcusspp.8%Pseudomonasaeruginosa8%Staphylococcusaureus20%Coagulase neg.staphylococci14%Escherichiacoli8%Enterococcusspp.12%Pseudomonasaeruginosa8%1986-1989(N=16,727)1990-1996(N=17,6
5、71)Microbiology of SSIs Unusual pathogensRhizopus oryzea-elastoplast adhesive bandageClostridium perfringens-elastic bandagesRhodococcus bronchialis-colonized health care personnelLegionella dumoffii and pneumophila-tap waterPseudomonas multivorans-disinfectant solution Cluster of unusual SSI pathog
6、ens formal epidemiologic investigationPathogenesis of SSI Relationship equationDose of bacterial contamination x Virulence Resistance of host SSI RiskSSI Risk Factors Age Obesity Diabetes Malnutrition Prolonged preoperative stay Infection at remote site Systemic steroid use Nicotine use Hair removal
7、/Shaving Duration of surgery Surgical technique Presence of drains Inappropriate use of antimicrobial prophylaxis Perioperative Preventive MeasuresRole of Antimicrobial Prophylaxis(AP)in Preventing SSI Refers to very brief course of an antimicrobial agent initiated just before the operation begins S
8、hould be viewed as an adjunctive preventive measure Appropriately administered AP associated with a 5-fold decrease in SSI rates Classification of surgical woundslCleanlClean-contaminatedlContaminatedlDirtySurgical wound infection rateslClean wound1-2%lClean prosthetic 5%lClean contaminated 10%lCont
9、aminatedappendix 60%Am J Surg 1994;167:15S-19SSite-specific infection rates without antimicrobial coverageSite of operation Wound infection rate(%)Colorectal 40Appendix,normal/inflamed/gangrenous 14/16/56 Gastroduodenal,not specified 27Duodenal ulcer,elective/obstructed/perforated 5/16/18Gastric ulc
10、er 23Gastric tumor 31UGI bleeding 49Cholecystectomy 15Vascular 13Head and neck 45Annu Rev Med 1993;44:385-93Definition of prophylaxis vs therapylProphylaxisantimicrobials given prior to attachment of contaminating bacteria to host tissues at the operation sitelTherapyantimicrobials given after possi
11、ble attachment“the routine use of prophylaxis in clean operations is unnecessary and undesirable”Dr.Maxwell FinlandRI Med J 1960;43:499-504 Kinetics of bacterial growth after its seeding into a surgical wound:I Surgical Procedure Kinetics of bacterial growth after its seeding into a surgical wound:I
12、I Surgical Procedure Antibiotics serumhematomaKinetics of bacterial growth after its seeding into a surgical wound:III Surgical Procedure Antibiotics in serumAntibiotics in clotAntibiotics administratedTiming of penicillin injection and the size of staphylococcal lesion in guinea pigMean 24 hr lesio
13、n size(mm)Lesion age in hrs when penicillin injectedStaphylococcal lesionsStaphylococcal lesions+PCKilled staphylococcal lesionsSurgery 1961;1:161-8Timing of prophylactic antibiotics and rates of surgical-wound infectionTime of No.of No.(%)of Relative risk Odds ratio Administration patients infectio
14、n(95%CI)Early369 14(3.8)6.7(2.9-14.7)4.3 Preoperative 1708 10(0.59)1.0Perioperative282 4(1.4)2.4(0.9-7.9)2.1Postoperative488 16(3.3)5.8(2.6-12.3)5.8All 2847 44(1.5)Early:2-24 hrs before incisionPreoperative:0-2 hrs before incisionPerioperative:within 3 hrs after incisionPostoperative:3 hrs after inc
15、isionNEJM 1992;326:281-6Rates of surgical-wound infection vs timing of prophylaxisHours after incisionIncisionInfection rate(%)NEJM 1992;326:281-6Wound infection related to time of initiation of prophylaxis with cefazolinArea of%infection when antibiotic was begun operation8-12 hr 1 hr1-4 hr Not giv
16、enpreop preoppostopGastric 5 4 1722Biliary 3 3 911Colonic 6 6 1515Ann Surg 1976;184:443Antibiotic levels in serum/0.4%fibrin clot in relation to MIC for E.coli&B.fragilisAntibiotics Min after IM MIC(mg/L)30 60240 EC BFGentamicin (S)14.3 16.5 4.1 4 -12.5 mg/kg(C)0.6 0.7 2Ampicillin(S)65.0 8.0 4.4 16
17、-200 mg/kg(C)2.0 2 2 Cefoxitin(S)3601503.6 8 16 375 mg/kg(C)4.2 20 4Clindamycin(S)25.0 60.0 18.0 -0.2 100 mg/kg(C)0.1 0.1 0.1 -0.2Arch Surg 1986;121:163-8Objectives of prophylaxis&therapylClean surgeryprevent extrinsic contamination of prosthesislClean-contaminated surgeryreduce the number of mucosa
18、-associated colonizing bacterialContaminated surgery(therapy)eradicate bacteria that have already become attached to host tissuesInfection rates in clean neurosurgical operations,controlled studies Infection rate(%)with without relativeprophylaxis prophylaxis risk1984 Geraghty 0.5 3.6 7.41986 Mollma
19、n NA NA 5.61986 Shapiro 2.8 11.7 4.11987 Young 1.0 3.8 3.91988 Blomstedt 1.8 7.4 4.1Neurosurgery 1989;24:401-5Differing actions of antimicrobials in therapy and prophylaxislRheumatic feveroral sulfonamides,oral penicillinslPostpartum endometritis after C/Scefazolin,cefoxitin,cefotetanlSurgical proph
20、ylaxis2nd,3rd cephalosporin,cefazolinRecommended antibiotic for prophylaxisl Gynecologic surgeryC/Scefazolin(1g IV)after cord clampHysterectomycefazolin(1g IV)Abortioncefazolin(1g IV)l Orthopedic surgeryOpen reductioncefazolin(1g IV)Internal fixationcefazolin(1g IV)Joint replacementcefazolin(1g IV)S
21、pinal fusionNo proven benefitLeg amputationcefoxitin(2g IV)Recommended antibiotic for prophylaxislGeneral surgeryGastric resectioncefazolin(1g IV)Gastrostomycefazolin(1g IV)Biliary surgerycefazolin(1g IV)Colon surgeryoral prophylaxis orcefoxitin,cefotetan(2g IV)Appendectomycefoxitin,cefotetan(2g IV)
22、Hernia repaircefazolin(1g IV)Levels of cefazolin&cephalothin in serum/bone tissue after IV dose of 1 gmminmg/gSurg Gyn Obstet 1989;168:283-9Results of cephalosporin prophylaxis for experimental wound in mice Contaminant TreatmentNo.Mean CFU/g Infection rate(%)S.aureus cefazolin42 22.5K 2.4 S.aureus
23、cefamandole 42 40.8K 7.1 S.aureus cefotaxime42 29.0K 2.4 S.aureus saline42 17.9K 76.2E.colicefazolin42 6.8K 0 E.colicefamandole 42 10.9K 0 E.colicefotaxime42 90.1K 2.4 E.colisaline42 25.7K 66.7Fecalcefazolin41 54.1K 9.8 Fecalcefamandole 41 36.6K 4.9 Fecalcefotaxime41 40.5K 9.8 Fecalsaline41 20.9K 85
24、.4Surgery 1985;98:30-4Comparative trial of cefazolin and moxalactam for prophylaxis of abdominal hysterectomy:total infection morbidityCefazolin Moxalactam Two-sided(N=108)(N=100)p valueSerious infection 1(1%)4(4%)NSMinor wound 5(5%)2(2%)NSUTI 5(5%)15(15%)0.021Febrile morbidity25(23%)17(17%)NSTotal3
25、6(34%)38(38%)NSObstet Gynecol 1985;66:372-6Intraoperative concentration(m mg/ml)of the cephalosporinsSpecimenCefamandole Cefoxitin CefazolinSerum At drug infusion 119.7 96.3 140.8 At 0.25 h 98.6 79.4 130.9 At 1 h 56.1 45.7 105.9 At 2.2 h 23.8 20.3 76.4 At 4 h 7.3 6.9 43.7Hematoma 21.1 17.2 41.9Muscl
26、e 14.7 12.6 15.7J Bone Joint Surg Am 1985;67:921-4Prophylactic antibiotics in appendicitisProphylactic antimicrobialNo.of patientsInfection operatedrate(%)Placebo 3951 21.7Cephalosporins 336 15.8Metronidazole 1325 10.8Broad-spectrum penicillins 114 8.8Antiaerobe/anaerobe 261 2.7Infect Dis Clin N Am
27、1992;6:613-25外科預防性投藥常碰到的疑惑外科預防性投藥常碰到的疑惑l已經在接受抗生素治療時，還該給嗎？l外科預防性投藥等同於心內膜炎的預防性投藥嗎？l在一個複雜的手術後，抗生素需一直給到所有管子均拔除為止嗎？l在作心導管、PTCA、或放心律調節器時該routine給預防性投藥嗎？Special considerations:IlReoperation through fresh or healing clean woundlElective large bowel operationclear liquid diet+whole gut lavage1 g neomycin+ery
28、thromycin 1 pm,2 pm,11pm the day before operationlPercutaneous endscopic gastrostmylCardiac operations with cardiopulmonary bypassSpecial considerations:IIlCesarean sectionslow risk vs high risklVascular graft,vascular reconstructions,and vascular-access shuntslPenile prostheses,LN dssections,&VP sh
29、untslEarly treatment of compound fractures&abdminal traumaSpecial considerations:IIIlPrevention of septic arthritis in a preexisting orthopedic prosthesislReplacement of prostheses and need for culturelBlood loss during operationlProlonged operation timeImpact of Prolonged Surgical Prophylaxis DESIG
30、N:Prospective POPULATION:CABG patients(N=2641)Group 1:pts who received 48 hrs of APImpact of Prolonged Surgical AP OUTCOMES Incidence of SSIIsolation of a resistant pathogen RESULTS:43%of patients received AP 48 hrSSI Incidence48 hrs group:8.8%(100/1139),p=1.0 Antimicrobial resistant pathogen OR 1.6
31、(95%CI 1.1-2.6)Enhanced Perioperative Glucose Control in Diabetic Patients DESIGN:Prospective,sequential study POPULATION:Diabetic patients undergoing cardiac surgery(N=2467)during 1987-1997Controls:pts who received intermittent subQ insulin(SQI)Treated:pts who received continuous intravenous(IV)ins
32、ulinFurnary AP;Ann Thorac Surg,2000Enhanced Perioperative Glucose Control in Diabetic Patients OUTCOMES Blood glucose 24 hours before=20%SSI ratesPre-operative Shaving/Hair RemovalMultiple studies show -Clipping immediately before operation associated with lower SSI risk than shaving or clipping the
33、 night before operationPre-operative Shaving/Hair RemovalSurgical Attire Scrub suits Cap/hoods Shoe covers Masks Gloves GownsSurgical Technique Removing devitalized tissue Maintaining effective hemostasis Gently handling tissues Eradicating dead space Avoiding inadvertent entries into a viscus Using
34、 drains and suture material appropriatelyParameters for Operating Room Ventilation*Temperature:68o-73oF,depending on normal ambient temp Relative humidity:30%-60%Air movement:from“clean to less clean”areas Air changes:15 total per hour 3 outdoor air per hour *American Institute of Architects,1996Role of Laminar Air Flow(Ultraclean Air)in Preventing SSI Most studies involve only orthopedic operations Lidwell et al:8,000 total hip and knee replacements ultraclean air:SSI rate 3.4%to 1.6%antimicrobial prophylaxis(AP):SSI rate 3.4%to 0.8%ultraclean air+AP:SSI rate 3.4%to 0.7%
