SURGICAL INFECTION 医疗7年制.ppt

1、SURGICAL INFECTION,By Dr.Shi Cheng Professor of Surgery Department of General Surgery Beijing Tiantan Hospital Capital Medical University,Contents,Introduction Classification Inflammation and systemic surgical infection Sepsis Fungal infection Tetanus The appropriate application of antibiotics,Intro

2、duction,Classification Specific and Nonspecific infection: invasive micro-organisms Specific infection: including tuberculosis,tentanus, gas gangrene, et al. Nonspecific infection: pyogenic Acute, subacute and chronic: duration.( two months) External infection and internal infection:invasive way Opp

3、ortunistic infection, superinfection, nosocomial infection : conditions,Inflammation and systemic surgical infection, SYSTEMIC INFLAMMATORY RESPONSE SYNDROME (SIRS),Patient presents with two or more of the following criteria. 1. temperature 38C or 90 beats/minute 3. respiration 20/min or PaCO2 12,00

4、0/mm3, 10% immature (band) cells,Etiology,Infection factor: the common cause, Sepsis. Non infection factor: severe trauma, burn, pancreatitis, shock, ischemia-reperfusion injury.,Pathophysiology,Local inflammation Systemic inflammation The role of inflammation mediator in SIRS Regulation and out of

5、control of the inflammation response,SIRS,Sepsis, The concepts,Sepsis The systemic inflammatory response to infection. Sepsis syndrome Sepsis (SIRS) associated with organ dysfunction, hypoperfusion, or hypotension. Hypoperfusion and perfusion abnormalities may include, but are not limited to, lactic

6、 acidosis, oliguria, or an acute alteration in mental status. Bacteremia. The presence of viable bacteria in circulating blood., Systemic Factors contributing to the increasing incidence of sepsis,1. Miscellaneous conditions: childbirth, septic abortion, trauma and widespread burns, intestinal ulcer

7、ation. 2. widespread use of corticosteroid and immunosuppressive therapies for organ transplants and inflammatory diseases 3. longer lives of patients predisposed to sepsis, cirrhosis of liver, diabetics, malnutrition, anemia, cancer patients, neutropenia, leukemia, dysproteinemias, patients with ma

8、jor organ failure, and with granulocytopenia. 4. Neonates and the elderly are more likely to develop sepsis (ex. group B Streptococcal infections). 5. aggressive oncological chemotherapy and radiation therapy 6. AIDS, local conditions at increased risks of developing sepsis,1. Opening trauma, burnin

9、g, perforation of gastrointestine, surgery, puncture 2. increased use of invasive devices such as surgical protheses, inhalation equipment, and intravenous and urinary catheters. 3. Intraductal obstruction 4. Foreign body or necrotic tissue. 5. Blood obstacle of local tissue,Etiology,Gram-negative b

10、acteria. Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus spp., Serratia spp., Neisseria meningitidis. Gram-positive bacteria. Staphylococcus aureus, coagulase-negative Staphylococcus, Streptococcus pneumoniae, Streptococcus pyogenes, enterococci. Other causes. Opportunistic

11、fungi (2% to 3%), viral, rickettsia, and protozoa, Outcome of Infecion,Resolution Abscess Formation Diffusion Chronic inflammation, Clinical Manifestations,Primary infection focus Systemic inflammation response Hypoperfusion abnormalities of organs.,Systemic inflammation response,Fever, chills. They

12、 may be absent in serious infections, especially in elderly individuals. WBC , leukocytosis with left shift Tachycardia, tachypnea Tachypnea accompanied with mild respiratory alkalosis and alteration in mental status maybe the only sign of the elder.,Hypoperfusion abnormalities of organs,lactic acid

13、osis, oliguria, Tachypnea, hypoxia, Pao2 An acute alteration in mental status. Hyperbilirubinemia,thrombocytopenia, Septic shock, organ failure,Physical Examination,Mild enlargement of liver or spleen Skin eruption(reddish patches) Metastatic abscess, Diagnosis,Disease Evidence Bacteremia Positive b

14、lood culture Sepsis The evidence of infection the manifestation of SIRS Sepsis syndrome Positive blood culture the evidence of sepsis Hypoperfusion of organs hypoxemia, oliguria, alteration in mental status, Diagnosis,Gram-positive bacteria sepsis Gram-negative bacteria sepsis Candida albicans sepsi

15、s Anaerobic bacteria sepsis,Different sepsis clinical characters,Sepsis common pathogenic fever chill shock rash disease bacteria metastatic abscess G+ Carbuncle Staphylococcus continued (-) warm (+) Cellulitis aureus remittent late pyogenic infection of bone and joint G- biliary, urinary Escherichi

16、a intermittent (+) cold (-) intestinal infection coli early serious burn Candida after applying Candidas (+) (+) (+) (-) albicans broad-spectrum albican antibiotics Anaerobic serious infection Bacteroides bacteria abdominal and fragilis (+) (+) (+) metastatic abscess pelvic cavity, Therapy,The origi

17、nal focus of infection must be treated surgical drainage may be needed in some cases The application of antibiotics Patients with severe sepsis should be in ICU. Support therapy Inhibition or blockade of inflammation mediator Monoclonal antibodies against gram-negative endotoxin, steroids, and anti-

18、TNF antibodies have not demonstrated significant reduction. Recent study suggests low-dose steroids may help in septic shock, but this is not yet standard of care.,Introduction, Surgical fungal infection is an opportunistic infection. The deeper infection is the major. Most surgical fungal infection

19、s are in fact due to Candida, but Aspergillus infections are also seen.,Pathogenesis,C. albicans is an asexual, diploid, dimorphic fungus that is widespread on humans and in their environment. We still dont understand why this common commensal sometimes becomes pathogenic, although impaired host def

20、ence mechanisms seem crucial.,Risk factors for opportunistic fungal infections,1. Neutropaenic patients following chemotherapy, and other oncology patients with immune suppression; 2. Persons immune compromised due to Acquired Immune Deficiency Syndrome caused by HIV infection; 3. Patients in intens

21、ive care (ICU), who are not necessarily neutropaenic, but are compromised due to the presence of long-term intravascular lines or other breaches in their integument, severe systemic illness or burns, and prolonged broad-spectrum antibiotic therapy.,Other (quoted) predisposing factors,APACHE score 10

22、; renal dysfunction; haemodialysis; surgery for acute pancreatitis, or even possibly splenectomy; recurent GIT perforation; Hickmann catheters.,Clinical manifestations,C. albicans cause digestive tract, respiratory tract and urinary tract infection. Blood disseminated candidiasis Aspergillus cause p

23、neumonia.,Diagnosis, If you dont suspect it, youll miss it! Conventional diagnosis of these infections, based on blood cultures or culture of the offending organism from multiple sites. Newer tests that have been advocated for early diagnosis of systemic fungal infection include: Sandwich ELISA for

24、circulating galactomannan PCR shows promise in the diagnosis of Candida infections, even unusual species.,Treatment,Therapy to etiology. Antifungal therapy. Amphotericin B 0.5-1mg/kg.d iv Fluconazole and other Azoles 400mg/first day, 200-400mg/d,Prevention,Appropriate applying antibiotics Prophylact

25、ic applying antifungal drugs,What is tetanus?,Tetanus is an acute, sometimes fatal, disease of the central nervous system, caused by the toxin of the tetanus bacterium, which usually enters the body through an open wound.,Pathogenesis,Tetanus results from infection with C tetani, a mobile, spore-for

26、ming, anaerobic, gram-positive bacillus. This bacillus is found in or on soil, manure, dust, clothing, skin, and 10-25% of human GI tracts. The spores need tissue with the proper anaerobic conditions to germinate; the ideal medium is wounds with tissue necrosis.,Pathogenesis,The spores of C tetani g

27、erminate and produce 2 toxins: tetanolysin and tetanospasmin. The action of the latter helps explain the clinical manifestations of the disease.,Pathogenesis,Tetanospasmin is synthesized as a single 151-kd chain and is cleaved to generate toxins with 2 chains joined by a single disulfide bond. The h

28、eavy chain (100 kd) is responsible for specific binding to neuronal cells and for protein transport. The light chain (50 kd) blocks the release of neurotransmitters.,Pathogenesis,Once the toxin is synthesized, it moves from the contaminated site to the spinal cord in 2-14 days. When the toxin reache

29、s the spinal cord, localized or cephalic tetanus may occur initially, followed by generalized tetanus.,Clinical Manifestation,IncubationThe incubation period for tetanus is usually 2 to 14 days, with most symptoms beginning around the 7- 8 day , but onset may range from 24 hours to 3 weeks.,Clinical

30、 Manifestation,Tetanus often begins with muscle spasms in the jaw (called trismus), accompanied by difficulty swallowing and stiffness or pain in the muscles of the neck, shoulders, or back. These spasms can spread to the muscles of the abdomen, upper arms, and thighs.,Symptoms,stiffness of jaw (als

31、o called lockjaw) difficulty swallowing contraction of facial muscles stiffness of abdominal and back muscles Sweating painful muscle spasms near the wound area (if these affect the larynx or chest wall, they may cause asphyxiation ),Physical,Common first signs of tetanus are headache and muscular s

32、tiffness in the jaw (ie, lockjaw), followed by neck stiffness, difficulty swallowing, rigidity of abdominal muscles, spasms, and sweating. Severe tetanus results in opisthotonos, flexion of the arms, extension of the legs, periods of apnea resulting from spasm of the intercostal muscles and diaphrag

33、m, and rigidity of the abdominal wall. Late in the disease, autonomic dysfunction develops, with hypertension and tachycardia alternating with hypotension and bradycardia.,Complications,The most common complication is spasm of the vocal cords and/or spasms of the respiratory muscles that cause inter

34、ference with breathing. Asphyxiation, pneumonia Other complications include muscle avulsion, fractures, dislocations tachycardia, and heart failure.,DIFFERENTIALS,Rabies Encephalitis Strychnine poisoning Other Problems to be Considered: Dental infectionsLocal infectionsHysteria,Prevention,There are

35、two important components of tetanus prevention: tetanus immunization (receiving routine tetanus vaccinations) and whats known as post-exposure tetanus prophylaxis (receiving a shot after an injury occurs).,Prevention,For children, tetanus immunization is part of the DTaP (diphtheria, tetanus, and ac

36、ellular pertussis) vaccinations. Active immunization Post-exposure tetanus prophylaxis also involves getting tetanus shots, but after an injury occurs. Passive immunization,Treatment,Thorough cleaning of the wound Neutronlize the free toxin Passive immunization with human tetanus immune globulin (TI

37、G) shortens the course of tetanus and may lessen its severity. A dose of 500 U appears as effective as larger doses. Or TAT 20000-50000U IV,Treatment,To control spasms Diazepam iv, 10mg tid. Luminal 0.1 im. Physicians also use sedative hypnotics, narcotics, inhalational anesthetics, neuromuscular bl

38、ocking agents, and centrally acting muscle relaxants (eg, intrathecal baclofen).,Treatment,Securing an adequate airway. A tracheotomy in severe cases (with respiratory problems) Antibiotics Metronidazole (eg, 0.5 g q6h) has comparable or better antimicrobial activity, and penicillin is a known antag

39、onist of GABA, as is tetanus toxin.,Treatment,Supportive therapy Parenteral nutrition Intensive nursing,The appropriate application of antibiotics,Background,The global increase in resistance to antimicrobial drugs, including the emergence of bacterial strains that are resistant to all available ant

40、ibacterial agents, has created a public health problem of potentially crisis proportions.,The role of antibiotics,Inhibits cell wall synthesis Impairment of bacterial DNA synthesis Disruption of membrane barrier function Disruption of ribosomal protein synthesis,The common used Antibiotics,A. Amphot

41、ericin B B. Penicillin C. Cephalosporins D. -lactamase : Imipenem E. Aminoglycosides F. Quinolones G.Clindamycin H.Antianaerobic-microbacterial drugs,* Prophylactic use of antibiotics perioperative period,Indication (1) Severe trauma, severe burn, Any wound with known gross bacterial contamination (

42、2) Operations entering the gastrointestinal tract, respiratory tract, female genital tract and bowel preparation before colon surgery (3) Implantation of any permanent prosthetic material (4) High risk factor of infection: Diabetes mellitus, elder, malnutrition,granulocytopenia,Steroids, Immunosuppr

43、ession , oncological chemotherapy et al. (5)Cardiac valvular disease or valve surgery, organ transplantation, Craniotomy,*Administration of prophylactic antibiotics,Choice of antibiotics Timing of administration Dosage selection Duration of prophylaxis Route of administration,Guidelines for Use,Choice of antibiotics The antibiotics selected for prophylaxis must cover the expected pathogens for that operative site. Cephalosporin Recommeded: Cefuroxime (2nd generation cephalosporin),Guidelines for Use,Timing of administration G