Current Concerns in Surgical Infection

Current Concerns in Surgical Infection  Surgical infection   Most common operative complication Most frequent nosocomial infection Potent antibiotics Management in ICU Shorter inpatient stay  Complacent attitude of a surgeon    外科部位感染 (SSI) 美國疾病管制中心 (CDC) 1992年定義   外科部位感染(SSI)可分成『切口處之外科部位感染』 (incisional SSI)及『器官/腔室之外科部位感染』 (organ/space SSI)。 A‧表淺切口之外科部位感染(superficial incisional SSI)：  a‧切口部位之感染發生在手術後三十天內。  b‧其範圍包括皮膚、皮下組織之切口。  B‧深部切口之外科部位感染(deep incisional SSI)：  a‧如果沒有植入物時，感染發生在手術後三十天內；有植入 物時，則感染發生在手術後一年內 b‧感染與該手術有關。 C‧感染範圍包括深部軟組織(如肌膜、肌肉層)，之切口。   器官/ 腔室之外科部位之感染 (organ/space SSI)   任何( 切口除外) 經由外科手術打開或者 處理過之身體結構。 具有下列條件：    a‧如果沒有植入物時，感染發生在手術後三 十天內；有植入物時，則感染發生在手術後 一年內； b‧感染與該手術有關。 c‧感染範圍包括了任何(切口除外)經由外科 手術打開或者處理過的身體結構。 Causes of Surgical Site Infection: Local Wound Factors  Use of foreign body   Suture Drain     Inaccurate approximation of the wound Tissue strangulation Dead tissue Hematoma, seroma Wound Classification and Risk Index Traditional Clean Clean-contaminated Contaminated SCENIC Contaminated or dirty Operation>2 hrs Abdominal operation NNIS Contaminated or dirty Operation>t hrs ASA>3 Dirty >3diagnoses Causes of Surgical Site Infection: Patient Factors     Age Reduced blood flow Decreased tissue oxygen tension Reduced vascular reactivity    Uremia Old age Steroid Cancer trauma  Generation of cell function inhibitors   Host Risk Factors       Disease severity index ASA class Morbid obesity Old age Prolonged preoperative stay Infection at other sites   Low albumin Malnutrition    Immunosuppression DM cancer Operation-related Risk Factors        Intraoperative contamination Surgical wound class No prophylactic antibiotics Low abdominal site Specific procedure Razor shave Prolonged duration of surgery      Tissue trauma Multiple procedure Prolonged hospital admission          Emergency operation Glove puncture No. of people in OR Dead space Poor hemostasis Inexperience Low procedure volume Unskilled surgeon Foreign material No scrub Drain Host Defenses  Barriers    Skin Mucus membranes Epithelial layers     Microbial flora Humoral defenses Cellular defenses Cytokines Microbial Flora     Autochthonous; Commensal; Resident; Indigeneous Many are symbionts Established in neonates: birth canal and initial feeding Gnotobiotic animals: germ-free     Poor gut-associated lymphoid tissue No response to local antigen Hepatic Kupffer cell defects: number and response Systemic cellular and humoral immune defect Autochthonous Microflora of Gastrointestinal Tract Colonization Resistance    Occupying potential binding site for pathogenic organisms Preventing aerobic G(-) bacilli invasion Greatest contribution: anaerobic Humoral Defenses  Immunoglobulin     Initial response: IgM Second set response: IgG IgA; secreted by gutassociated lymphoid Antigen presenting cells  B lym, M∮, DC, Langerhans cell,    Helper T lym B lym Plasmatocyte  Complement Cellular Defenses & Cytokine    Macrophages Neutrophils Others? Interactions of Various Portions of Host Defenses Classes of Antibiotics          b-lactam Quinolons Aminoglycosides Antianaerobes Macrolides Tetracyclines Glycopeptides Streptogramins Oxazolidinones Structures of B-lactam Antibiotics     Penicillin Cephalosporin Cabapenem Monobactam G(-) Sepsis, Shock, and MODS  Physiologic host responses  Fever  Acidosis  Hypoxemia  Hyperkalemia  Hyperglycemia  Decreased systemic vascular resistance  Elevated cardiac output  Hypotension   Neither bacteria, bacterial toxins, nor host-mediated event alone account for these alterations G(-) bacterial LPS (endotoxin) is responsible G(-) lipopolysaccharide  O-antigen    Polysaccharide subunit Hydrophilic Serotype diversity   Lipid A Core region  Highly conservation Surgical Procedures, Pathogens and Antimicrobial Prophylaxis-Nichols 1995 Procedure Facultative S. aureus, S. epider Strep. Bacteroid (not B. fragilis) Anaerobic Antitiotics Route Altrenative 2nd/3rd-Gn cephalosporin or vancomycin 2nd/3rd-Gn cephalosporin clean Gastroduodenal 1-Gn cephalo- iv sporn cefazolin iv Biliary Colectomy Small bowel resection Coliform, enterococci coliform coliform clostridia cefazolin iv po po iv iv 2nd/3rd-Gn cephalosporin GM+metronidazole +tetracyclin Aerobic+anaerobic coverage Aerobic+anaerobic coverage Aerobic+anaerobic coverage B. fragilis, Peptostrp., Neomycinclostridia erythromycin B. fragilis, Peptostrp. B. fragilis, Peptostrp Neomycinerythromycin Cefoxitin or Ceftizoxime Appendectomy coliform Abdominal penetration coliform B. fragilis, Peptostrp., Cefoxitin or clostridia Ceftizoxime Antibiotics With Aerobic or Anaerobic Broad-spectrum Activity  Aerobic coverage         GM Tobramycin Amikacin Netilmicin Cefotaxime Ceftizocin Ceftriaxone Ceftazidime     Aztreonam Ciprofloxacin Ofloxacin levofloxacin Clindamycin Metronidazole chloramphenicol  Anaerobic coverage    Major aerobic pathogens in surgical wound infections-NNISS 1991 Pathogen Infection (%) Staph. aureus Enterococci Coagulase(-) Staph. E-coli 17 13 12 10 Pseudomonas aerug. Enterobacter spp. Proteus mirabilis Kleb. Pneumoniae 8 8 4 3 Streptococci spp. Citrobacter alb. & spp. Serratia marcescens 3 3 1 First 3 days Postoperative Fever   Most likely a noninfectious cause Two important infectious causes after laparotomy   Bowel leakage Soft tissue infection  Toxic shock syndrome Postoperative Fever   Most postoperative febrile patients are not infected Most common nonsurgical causes of postoperative infection and fever    UTI URI IV catheter-related infection History taking Physical examination  Most sensitive test for detecting infection   Clinical presentations of SWI     4th postoperative day Pain, tenderness, swelling, erythema, increased warmth S. aureus Infection within 48 hrs postop.   b-hemolytic strep. Anaerobic clostridia  Rarely polymicribic Catheter-related bacteremia    All Central venous catheters colonized by bacteria 24 hrs after catheter insertion Major sources: skin and catheter hub Risk factors of bacteremia         Prolonged catheterization Frequent manipulation Improper aseptic insertion and maintence Types of catheter material Poor placement of the catheter Occlusive transparent plastic dressings Contaminated skin solution Use of lipid infusions Preventing strategies to Catheter-related bacteremia     A skilled infusion therapy team Antimicrobial flushing solutions Topical disinfectants Coating catheter with antimicrobial agents Management of Catheter-related bacteremia Organism Coagulase(-) staph. Staph. aureus Candida spp. G(-) bacilli G(+) bacilli Early catheter removal No Yes Yes Yes Yes antimicrobials Vancomycin (ORSA) Vancomycin (ORSA) Amphotericin B or Fluconazole Based on sensitivity test Based on sensitivity test Duration of treatment 7D 10-14 D 10-14 D 7D 7D 林口長庚醫院各類微生物培養 Top 10 菌株及百分比 Gm(-) bacteria 菌名 E.coli Kleb.pneumoniae Ps.aeruginosa Acineto.baumannii Entero.cloacae Proteus mirabilis Sal.enteritidis B Serratia marcescens Morganella morganii Aeromonas hydrophila 百分比 33.5% 16.4% 8.0% 6.4% 4.0% 2.5% 1.9% 1.9% 1.9% 1.8% Gm(+) bacteria 菌名 Coag(-) staphylococcus Staphy.aureus Viridans streptococcus Micrococcus Corynebacterium sp Bacillus Enterococcus faecalis Strepto.pneumoniae Staphy.epidermidis B-Strepto.Gr.B 百分比 49.9% 17.7% 5.5% 3.8% 3.4% 3.3% 2.4% 2.3% 1.5% 1.2% Anaerobes 百分比 B.fragilis 27.7% Propio.acnes 12.7% Propionibacterum sp 9.2% B.thetaiotaomicron 8.5% Fusobacterium sp 4.6% Prevotella sp 4.6% Clost.perfringens 3.8% Clostridium sp 3.8% Bacteroides sp 3.1% Gm(+) no spore forming bacilli 3.1% 菌名 Gram-Positive Cocci  Coagulase(+) Staphy.    Most common pathogens in SSI 100% resistant to PCN ORSA: Vancomycin, linezolid, Q/D   Coagulase(-) Staphy. Streptococci   Sensitive to b-lactam antibiotics Never a sole cause of SSI Grave prognosis GM+ampicillin (or vancomycin) VRE: linezolid, Q/D  Entericocci    G(+) Bacteria BACTERIA Coag. (-) staphylococci Enterococcus faecium Enterococcus faecalis ANTIBIOTICS PERCENT OF SUSCEPTIBILITY** AMPICILLIN CEFTRIAXONE CEFUROXIME CLINDAMYCIN ERYTHROMYCIN OXACILLIN PENICILLIN-G SXT TEICOPLANIN VANCOMYCIN 99 100 99 33 87 86 29 25 32 2 52 100 100 60 20 11 7 55 100 100 53 29 21 6 57 100 100 89 28 53 100 99 47 49 99 100 100 94 62 47 80 100 100 Viridans streptococci - Staph. epidermidis Staph. aureus Beta strep. group B Strep. pneumoniae Aerobic and Facultative GramNegative Rods-1   Enterobacteriaceae: anaerobic Easy G(-) rods: E-coli, Proteus, Klebsiella   Relatively common in mixed SSI Relatively sensitive to 2nd generation cephalosporins  Difficult G(-) rods: Enterobacter, Morganella, Seratia, Providencia  Greater intrinsic antibiotic resistence  Some acquire extended spectrum b-lactamase activity Aerobic and Facultative GramNegative Rods-2  Obligate aerobic G(-) rods  Pseudomonas    Common in hospital-acquired pneumonia Oftenn antiotic resistence Ceftazidime, aztreonam, imipenem, ciprofloxacin, acylureido-penicillin, aminoglycoside?? Aztreonam resistant Two drugs combinations even after sensitivity test Resistant to imipenem and meropenem Emerging as these drugs are used  Acinectobacter    Strenotrophomonas   Anaerobes     Most numberous inhabitants of normal GI tract and mouth Multiplicating in dead tissue Surgical infections, mostly Bacteroides fragilis  Metronidazole, clindamycin, chloramphenicol, imipenem  Clostridium  C. difficile, C. tetanus G(-) bacteria sensitivity test Aeromonas hydrophila Morganella morganii Acinetob. baumannii Serratia marcescens Kleb. pneumoniae Proteus mirabilis Enterob. cloacae Ampicillin Cephazolin CAZ CXM CIP GM IPM 31 32 21 80 1 7 97 90 93 97 69 22 82 93 88 83 74 100 1 2 69 59 92 77 100 0 94 98 94 94 94 100 0 2 87 4 86 55 100 39 80 100 97 94 73 100 89 85 79 88 27 97 - Sal. enteritidis B Ps. aeruginosa E. coli 0 0 94 2 62 48 100 Guidelines for the Management of Acute Pancreatitis     1992 Atlanta International Symposium on acute pancreatitis 1997 Santorini consensus conference 2000 Patient care guidelines, Society for surgery of the alimentary tract 2002 World Congress of Gastroenterology, working party report Patient presentation#20290617  43 male   Epigastralgia and back pain for 1 day Nausea and vomiting for 6 hours   Alcohol: social; Smoking: 1.5 PPD for 20 Y HTN with regular medication, no DM Hx  Initial data   WBC=22.2 k/mL, Hb= 19.0 g/dL, Glucose= 440 mg/dL,    Amylase=1932 U/L, Lipase= 12880 U/L, BUN=24 mg/dL, Cr=2.0 mg/dL, Bilirubin= 0.9 mg/dL,  Ca=6.5 mg/dL, Na=128 meq/L Management  Initial:Jul 9  NPO    IVF H2 blockers Abdominal CT scan, Jul 9  Antibiotic?  Jul 19  CT scan and CT guide drainage Abdominal CT: Jul 9 vs. Jul 19 Abdominal CT: Aug 7 Surgical intervention     Aug 14: necrosectomy, open drainage and Karlex gauze packing, suture ligation of bleeders Aug 15: change Karlex and check bleeding, open drain Sep 14: Necrosectomy, open drain Nov 4: discharge Culture data  Jul 19   Stenotrophomonas maltophilia  Ceftazidine, Ciprofloxacin, SXT Acinebacter sp  Imipenenm  Aug 30  Staphylococcus aureus  Chloramphenicol, Teicoplanin, Vancomycin Staphylococcus aureus  Chloramphenicol, Teicoplanin, Vancomycin  Oct 9  Consulting Infection Professionals  Jul 9  Cefamezine+GM+Metronidazole    Jul 19  Ceftazidine Aug 30  Vancomycin+Imipenenm Oct 9  Vancomycin Antibiotic Prophylaxis in Acute Pancreatitis  Randomized controlled trials       Pederzoli: 72 pts with imipenem, 1993 SGO Sainio: 60 pts with cefuroxime, 1995 Lancet Schwarz: 26 pts with metronidazole and ofloxacin Luiten: 102 pts with SDD, 1995 Ann Surg Delcenserie: 23 pts with ceftazidime, amikacine and metronidazole, 1996 Pancreas Bassi: 60 pts with pefloxacin and imipenem, 1998 Gastroenterology  Meta-analysis   Golub, 1998 J Gastrointest Surg Sharma and Howden, 2001 Pancreas Antibiotic Prophylaxis in Acute Pancreatitis With Pancreatic Necrosis  Recent evidence     Reduction in infected necrosis:6/6 Decrease in surgical indications:6/6 Lessened rates in morbidity, MOF:4/6 Improvement in survival:2/6 Fungal infection Bacterial resistance  The concerns？  