1、SURGICAL INFECTIONBy Dr.Shi ChengProfessor of SurgeryDepartment of General SurgeryBeijing Tiantan HospitalCapital Medical UniversityContents?Introduction?Classification?Inflammation and systemic surgical infection?Sepsis?Fungal infection?Tetanus?The appropriate application of antibioticsIntroduction

2、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?Opportunist

3、ic infection, superinfection, nosocomial infection : conditionsInflammation and systemic surgical infection?SYSTEMIC INFLAMMATORYRESPONSE 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 12,000/mm3, 10%

4、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 control of t

5、he inflammation responseSIRSSepsis?The concepts?SepsisThesystemicinflammatoryresponsetoinfection.?SepsissyndromeSepsis(SIRS)associatedwithorgandysfunction,hypoperfusion,orhypotension.Hypoperfusionandperfusionabnormalitiesmayinclude,butarenotlimitedto,lacticacidosis,oliguria,oranacutealterationinment

6、alstatus.?Bacteremia.Thepresenceofviablebacteriaincirculatingblood.?SystemicFactors contributing to the increasing incidence of sepsis1. Miscellaneous conditions: childbirth, septic abortion, trauma and widespread burns, intestinal ulceration.2.widespread use of corticosteroid and immunosuppressive

7、therapies for organ transplants and inflammatory diseases3. longer lives of patients predisposed to sepsis, cirrhosis of liver, diabetics, malnutrition, anemia, cancer patients, neutropenia, leukemia, dysproteinemias, patients with major organ failure, and with granulocytopenia. 4.Neonates and the e

8、lderly 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 sepsis1. Opening trauma, burning, perforation of gastrointestine, surgery, puncture 2.increased use

9、 of invasive devices such as surgical protheses, inhalation equipment, and intravenous and urinary catheters. 3.Intraductal obstruction4. Foreign body or necrotic tissue. 5.Blood obstacle of local tissue EtiologyA.Gram-negative bacteria. Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginos

10、a, Proteusspp., Serratiaspp., Neisseria meningitidis. B.Gram-positive bacteria.Staphylococcus aureus, coagulase-negative Staphylococcus, Streptococcus pneumoniae, Streptococcus pyogenes, enterococci. C.Other causes. Opportunistic fungi (2% to 3%), viral, rickettsia, and protozoa?Outcome of Infecion?

11、Resolution?Abscess Formation?Diffusion?Chronic inflammation?Clinical Manifestations?Primary infection focus?Systemic inflammation response?Hypoperfusion abnormalities of organs.Systemic inflammation response?Fever, chills. They may be absent in serious infections, especially in elderly individuals.?

12、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 acidosis, oliguria, ?Tachypnea, hypoxia, Pao2?An acute alteration in mental s

13、tatus. ?Hyperbilirubinemia,thrombocytopenia, ?Septic shock, organ failurePhysical Examination?Mild enlargement of liver or spleen?Skin eruption(reddish patches)?Metastatic abscess?DiagnosisDisease EvidenceBacteremia Positive blood cultureSepsis The evidence of infectionthe manifestationof SIRSSepsis

14、 syndromePositive blood culture the evidence of sepsisHypoperfusion of organs hypoxemia, oliguria, alteration in mental status?Diagnosis?Gram-positive bacteria sepsis?Gram-negative bacteria sepsis?Candida albicans sepsis?Anaerobic bacteria sepsisDifferent sepsis clinical charactersSepsis common path

15、ogenic fever chill shock rashdisease bacteria metastatic abscess G+ CarbuncleStaphylococcuscontinued (-) warm (+)Cellulitisaureusremittent latepyogenic infection of bone and jointG-biliary, urinaryEscherichia intermittent (+) cold (-) intestinal infection coli earlyserious burnCandidaafter applying

16、Candidas(+) (+) (+) (-)albicansbroad-spectrum albicanantibioticsAnaerobicserious infectionBacteroidesbacteriaabdominal and fragilis(+) (+) (+) metastatic abscesspelviccavity?Therapy?The original focus of infection must be treatedsurgical drainagemay be needed in some cases?The application of antibio

17、tics?Patients with severe sepsis should be in ICU.?Support therapy?Inhibition or blockade of inflammation mediatorMonoclonal antibodies against gram-negative endotoxin, steroids, and anti-TNF antibodies have not demonstrated significant reduction. Recent study suggests low-dose steroids may help in

18、septic shock, but this is not yet standard of care.Introduction?Surgical fungal infection is an opportunisticinfection.?The deeper infection is the major.?Most surgical fungal infections are in fact due to Candida, but Aspergillus infections are also seen.Pathogenesis?C. albicans is an asexual, dipl

19、oid, 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 defence mechanisms seem crucial.Risk factors for opportunistic fungal infections1.Neutropaenic patients following chemo

20、therapy, and other oncology patients with immune suppression; 2.Persons immune compromised due to Acquired Immune Deficiency Syndrome caused by HIV infection; 3.Patients in intensive care (ICU), who are not necessarily neutropaenic, but are compromised due to the presence of long-term intravascular

21、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; ?renal dysfunction; ?haemodialysis; ?surgery for acute pancreatitis, or even possibly splenectomy; ?recurent GIT perfora

22、tion; ?Hickmann catheters. Clinical manifestations?C. albicans cause digestive tract, respiratory tract and urinary tract infection.?Blood disseminated candidiasis?Aspergillus cause pneumonia.Diagnosis?If you dont suspect it, youll miss it!?Conventional diagnosis of these infections, based on blood

23、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 circulating galactomannan ?PCR shows promise in the diagnosis of Candida infections, even unusual species.Treatment?The

24、rapy to etiology.?Antifungal therapy.Amphotericin B 0.5-1mg/kg.d ivFluconazole and other Azoles400mg/first day, 200-400mg/dPrevention?Appropriate applying antibiotics?Prophylactic applying antifungal drugsWhat is tetanus?Tetanus is an acute, sometimes fatal, disease of the central nervous system, ca

25、used 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-forming, anaerobic,gram-positive bacillus.?This bacillus is found in or on soil, manure, dust, clothing, skin, and 10-25% of huma

26、n 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 tetanigerminate and produce 2 toxins: tetanolysin and tetanospasmin. ?The action of the latter helps explain the clinical manifestations

27、 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 heavy chain (100 kd) is responsible for specific binding to neuronal cells and for protein transport. The light chain (50 kd) blo

28、cks 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 reaches the spinal cord, localized or cephalic tetanus may occur initially, followed by generalized tetanus. Clinical ManifestationIncu

29、bationThe 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 Manifestation?Tetanus often begins with muscle spasms in the jaw (called trismus), accompanied by difficulty swallowing and stiffne

30、ss 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 (also called lockjaw)?difficulty swallowing ?contraction of facial muscles ?stiffness of abdominal and back muscles?Sweating?painful mus

31、cle 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 stiffness in the jaw (ie, lockjaw), followed by neck stiffness, difficulty swallowing, rigidity of abdominal muscles, spasms, and sw

32、eating. ?Severe tetanus results in opisthotonos, flexion of the arms, extension of the legs, periods of apnea resulting from spasm of the intercostal muscles and diaphragm, and rigidity of the abdominal wall.?Late in the disease, autonomic dysfunction develops, with hypertension and tachycardia alte

33、rnating with hypotension and bradycardia.Complications?The most common complication is spasm of the vocal cords and/or spasms of the respiratory muscles that cause interference with breathing. Asphyxiation, pneumonia?Other complications include ?muscle avulsion, fractures, dislocations ?tachycardia,

34、 and heart failure.DIFFERENTIALS ?Rabies?Encephalitis?Strychnine poisoning ?Other Problems to be Considered: Dental infectionsLocal infectionsHysteriaPrevention?There are two important components of tetanus prevention: tetanus immunization(receiving routine tetanus vaccinations) and whats known as p

35、ost-exposure tetanus prophylaxis (receiving a shot after an injury occurs).Prevention?For children, tetanus immunization is part of the DTaP (diphtheria, tetanus, and acellular pertussis) vaccinations.Active immunization?Post-exposure tetanus prophylaxis also involves getting tetanus shots, but afte

36、r an injury occurs.Passive immunizationTreatment?Thorough cleaning of the wound?Neutronlize the free toxinPassive immunization with human tetanus immune globulin (TIG) shortens the course of tetanus and may lessen its severity. A dose of 500 U appears as effective as larger doses. Or TAT 20000-50000

37、U IVTreatment?To control spasmsDiazepam iv, 10mg tid. Luminal 0.1 im. Physicians also use sedative hypnotics, narcotics, inhalational anesthetics, neuromuscular blocking agents, and centrally acting muscle relaxants (eg, intrathecal baclofen).Treatment?Securing an adequate airway.A tracheotomy in se

38、vere cases (with respiratory problems) ?AntibioticsMetronidazole (eg, 0.5 g q6h) has comparable or better antimicrobial activity, and penicillin is a known antagonist of GABA, as is tetanus toxin.Treatment?Supportive therapyParenteral nutrition?Intensive nursingThe appropriate application of antibio

39、ticsBackground?The global increase in resistance to antimicrobial drugs, including the emergence of bacterial strains that are resistant to all available antibacterial agents, has created a public health problem of potentially crisis proportions.The role of antibiotics?Inhibits cell wall synthesis?I

40、mpairment of bacterial DNA synthesis?Disruption of membrane barrier function?Disruption of ribosomal protein synthesisThe common used AntibioticsA. Amphotericin BB. PenicillinC. CephalosporinsD. -lactamase: ImipenemE. AminoglycosidesF. QuinolonesG.ClindamycinH.Antianaerobic-microbacterial drugs *Pro

41、phylactic use of antibiotics perioperative period?Indication(1)Severetrauma,severeburn,Anywoundwithknowngrossbacterialcontamination(2)Operationsenteringthegastrointestinaltract,respiratorytract,femalegenitaltractandbowelpreparationbeforecolonsurgery(3)Implantationofanypermanentprostheticmaterial(4)H

42、ighriskfactorofinfection:Diabetesmellitus,elder,malnutrition,granulocytopenia,Steroids,Immunosuppression,oncologicalchemotherapyetal.(5)Cardiacvalvulardiseaseorvalvesurgery,organtransplantation,Craniotomy*Administration of prophylactic antibiotics?Choice of antibiotics ?Timing of administration ?Dos

43、age selection?Duration of prophylaxis?Route of administrationGuidelines for UseChoice of antibiotics?The antibiotics selected for prophylaxis must cover the expected pathogens for that operative site. CephalosporinRecommeded:Cefuroxime (2nd generation cephalosporin)Guidelines for Use?Timing of administration Give single dose injection 0-2 hours preoperationideally within 30 minutes of the inductionof anaesthesia?Dosage selectionAsinglestandardtherapeuticdoseofantibioticissufficientforprophylaxisundermostcircums