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?Opportunistic infect
3、ion,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%immature(band)cell
4、s 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 the inflammation responseSIR
5、SSepsis?The concepts?SepsisThesystemicinflammatoryresponsetoinfection.?Sepsis syndromeSepsis(SIRS)associatedwithorgandysfunction,hypoperfusion,or hypotension.Hypoperfusionand perfusionabnormalitiesmay include,but are not limited to,lacticacidosis,oliguria,or an acute alteration inmental status.?Bact
6、eremia.The presence of viable bacteria in circulatingblood.?Systemic Factors 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 therapies fo
7、r 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 elderly are more likely t
8、o 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 of invasive devices such as surgi
9、cal 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 aeruginosa,Proteusspp.,Serratia spp.,Neisseria meni
10、ngitidis.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?Resolution?Abscess Formation?Diffusion?Chronic inflammat
11、ion?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.?WBC?,leukocytosis with left shift?Tachycardia,tachypnea?Tac
12、hypnea 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 status.?Hyperbilirubinemia,thrombocytopenia,?Septic shock,organ fai
13、lurePhysical Examination?Mild enlargement of liver or spleen?Skin eruption(reddish patches)?Metastatic abscess?DiagnosisDisease EvidenceBacteremia Positive blood cultureSepsis The evidence of infectionthe manifestationof SIRSSepsis syndromePositive blood culture the evidence of sepsisHypoperfusion o
14、f 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 pathogenic fever chill shock rashdisease bacteria metastatic abscess G+Carb
15、uncleStaphylococcus continued(-)warm (+)Cellulitisaureusremittent latepyogenic infection of bone and jointG-biliary,urinaryEscherichia intermittent (+)cold (-)intestinal infection coli earlyserious burnCandida after applying Candidas(+)(+)(+)(-)albicansbroad-spectrum albicanantibioticsAnaerobicserio
16、us infectionBacteroidesbacteria abdominal and fragilis(+)(+)(+)metastatic abscesspelviccavity?Therapy?The original focus of infection must be treatedsurgical drainage may be needed in some cases?The application of antibiotics?Patients with severe sepsis should be in ICU.?Support therapy?Inhibition o
17、r 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 septic shock,but this is not yet standard of care.Introduction?Surgical fungal inf
18、ection 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,diploid,dimorphic fungus that is widespread on humans and in their environment.We still do
19、nt understand why this common commensal sometimes becomes pathogenic,although impaired host defence mechanisms seem crucial.Risk factors for opportunistic fungal infections1.Neutropaenic patients following chemotherapy,and other oncology patients with immune suppression;2.Persons immune compromised
20、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 lines or other breaches in their integument,severe systemic illness or burns,and prolonged broa
21、d-spectrum antibiotic therapy.Other(quoted)predisposing factors?APACHE score 10;?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
22、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 cultures or culture of the offending organism from multiple sites.Newer tests that have been advocated for ear
23、ly diagnosis of systemic fungal infection include:?Sandwich ELISA for 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 ivFluconazole and other Azoles400mg/first day,20
24、0-400mg/dPrevention?Appropriate applying antibiotics?Prophylactic applying antifungal drugsWhat 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 r
25、esults 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 human GI tracts.The spores need tissue with the proper anaerobic conditions to germinate;the ideal medium is wounds with tissue nec
26、rosis.Pathogenesis?The spores of C tetani germinate 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
27、 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)blocks the release of neurotransmitters.Pathogenesis?Once the toxin is synthesized,it moves from the contaminated site to the spinal cord in
28、 2-14 days.When the toxin reaches the spinal cord,localized or cephalic tetanus may occur initially,followed by generalized tetanus.Clinical ManifestationIncubationThe 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 ho
29、urs to 3 weeks.Clinical 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?stiffn
30、ess of jaw(also 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
31、muscular stiffness 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
32、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 interfere
33、nce 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 infectionsHysteriaPrevention?There are two importan
34、t 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 acellular pertussis)vac
35、cinations.Active immunization?Post-exposure tetanus prophylaxis also involves getting tetanus shots,but after 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 tet
36、anus and may lessen its severity.A dose of 500 U appears as effective as larger doses.Or TAT 20000-50000U 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 musc
37、le relaxants(eg,intrathecal baclofen).Treatment?Securing an adequate airway.A tracheotomy in severe 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?Suppor
38、tive therapyParenteral nutrition?Intensive nursingThe appropriate application of antibioticsBackground?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
39、 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 synthesisThe common used AntibioticsA.Amphotericin BB.PenicillinC.CephalosporinsD.-lactamase:ImipenemE.Am
40、inoglycosidesF.QuinolonesG.ClindamycinH.Antianaerobic-microbacterial drugs*Prophylactic use of antibiotics perioperative period?Indication(1)Severetrauma,severeburn,Anywound withknown grossbacterialcontamination(2)Operations entering thegastrointestinaltract,respiratorytract,female genital tract and
41、bowelpreparation beforecolonsurgery(3)Implantation ofanypermanent prosthetic material(4)Highriskfactor ofinfection:Diabetes mellitus,elder,malnutrition,granulocytopenia,Steroids,Immunosuppression,oncological chemotherapyetal.(5)Cardiac valvulardiseaseorvalvesurgery,organtransplantation,Craniotomy*Ad
42、ministration of prophylactic antibiotics?Choice of antibiotics?Timing of administration?Dosage 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.Cephalosp
43、orinRecommeded: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 selectionA singlestandard therapeutic doseof antibiotic issufficientforprophylaxisunderm
44、ostcircumstances.?Re-dosing(1)cases 4 hours,(2)significantblood loss,(3)gross contamination.Guidelines for UseDuration of prophylaxis?A single dose of antibioticwitha longenough half-life toachieve activitythroughout?The operation is recommended.upto 24hoursof antibiotic prophylaxis shouldbeconsider
45、ed forarthroplasty.Guidelines for UseRoute of Administration?Prophylactic antibiotics forsurgicalprocedures shouldbeadministeredintravenously.Surgical ProphylaxisWoundClassificationAntibioticPCN AllergyI1stgeneration CephalosporinaztreonamClindamycinII-Biliary,GU,Upper Digestive1stgeneration Cephalo
46、sporinaztreonamClindamycinII-Distal Digestive2ndgeneration CephalosporinAztreonam and Clindamycin/FlagylIII/IVGenerally TherapeuticTreat Surgical InfectionIndication?Unlocalized surgical infection?Treatment of surgical infection combined with operationPrinciple?Initial stage:empiric antibiotics?Acco
47、rding to bacteria culture plus drug sensitive testMethods?Way:intravenous and oral?Dose:lean body weight?Duration:5-7days?Combined Side effect?Toxicity?Allergy?Superinfection?ResistanceSummaryIn this class the following content is to be presented?Inflammatory response and systemic surgical infectionTo grasp the concept of SIRS,Sepsis,Sepsis syndrome,Bacteriemia and the diagnosis and treatment of Sepsis.?Fungal infections in surgical patients?TetanusTo grasp the diagnosis and treatment of tetanus.?The principles of anti-microbial therapy Thank you for your attention!
