{"id":690,"date":"2020-02-17T20:48:08","date_gmt":"2020-02-17T15:18:08","guid":{"rendered":"https:\/\/medicineplexus.com\/?p=690"},"modified":"2020-02-17T20:48:08","modified_gmt":"2020-02-17T15:18:08","slug":"nosocomial-infection","status":"publish","type":"post","link":"https:\/\/medicineplexus.com\/nosocomial-infection\/","title":{"rendered":"Nosocomial Infection"},"content":{"rendered":"\n<p><strong>Nosocomial Infection<\/strong><\/p>\n\n\n\n<p>Hospitals bring together vulnerable hosts &nbsp;\u00e0 Subject them to particular risk of infection \u00e0 Cause of morbidity and mortality \u00e0 &nbsp;Limits&nbsp; effectiveness, adds greatly to cost.<\/p>\n\n\n\n<p><strong>Hospital-acquired infection (HAI) ( nosocomial infection<\/strong>)<\/p>\n\n\n\n<ul><li>An infection acquired in hospital by a patient who was admitted for a reason other than that infection . or<\/li><li>An infection occurring in a patient in a hospital or other health care facility in whom the infection was not present or incubating at the time of admission. This includes infections acquired in the hospital but appearing after discharge, and also occupational infections among staff of the facility<\/li><\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"569\" height=\"452\" src=\"https:\/\/medicineplexus.com\/wp-content\/uploads\/2020\/02\/image-260.png?w=569\" alt=\"\" class=\"wp-image-714\" srcset=\"https:\/\/medicineplexus.com\/wp-content\/uploads\/2020\/02\/image-260.png 569w, https:\/\/medicineplexus.com\/wp-content\/uploads\/2020\/02\/image-260-300x238.png 300w\" sizes=\"(max-width: 569px) 100vw, 569px\" \/><\/figure>\n\n\n\n<p><strong>Impact of HAI<\/strong><\/p>\n\n\n\n<ul><li>Add to functional disability and emotional stress<\/li><li>May lead to disabling conditions that reduce the quality of life<\/li><li>One of the leading causes of death<\/li><li>Add to the imbalance between resource allocation<\/li><li>Significant cause of increased morbidity and mortality in hospitalized patients<\/li><li>80% of all hospital deaths are directly or indirectly related to HAIs (Hugheset al., 2005)<\/li><li>Prevalence varies from 3.8% to 18.6% depending on the population surveyed and the definitions used (Jensen, 2008)<\/li><li>Economic burden<\/li><\/ul>\n\n\n\n<p><strong>Factors influencing development of HAI<\/strong><\/p>\n\n\n\n<p><strong>The microbial agent<\/strong> \u2013<\/p>\n\n\n\n<ul><li>Resistance to antimicrobial agents<\/li><li>intrinsic virulence<\/li><li>amount of infective material.<\/li><\/ul>\n\n\n\n<p><strong>Patient susceptibility<\/strong> \u2013<\/p>\n\n\n\n<ul><li>age<\/li><li>immune status<\/li><li>underlying disease<\/li><li>diagnostic and therapeutic interventions<\/li><li>extremes of life<\/li><\/ul>\n\n\n\n<p><strong>Environmental factors \u2013<\/strong><\/p>\n\n\n\n<ul><li>Crowded conditions within the hospital<\/li><li>frequent transfers of patients&nbsp; from one unit to another<\/li><li>concentration of patients highly susceptible to infection in one area<\/li><\/ul>\n\n\n\n<ul><li><strong>Bacterial resistance<\/strong> &#8211; multidrug resistant strains of bacteria<\/li><\/ul>\n\n\n\n<p><strong>Source of the infecting organism<\/strong><\/p>\n\n\n\n<ul><li>exogenous(equipment)<\/li><li>another patient ( cross infection )<\/li><li>hospital staff<\/li><li>hospital environment<\/li><li>endogenous<\/li><\/ul>\n\n\n\n<p><strong>Modes of Spread of Infection<\/strong><\/p>\n\n\n\n<ul><li>By Contact: \u2022 Staff \u2022 Environment (including operation theatre) \u2022 Equipment (including blood products)<\/li><li>Air borne<\/li><li>Water borne<\/li><li>Food borne<\/li><\/ul>\n\n\n\n<p><strong>Infection by contact<\/strong><\/p>\n\n\n\n<p><strong>From staff:<\/strong><\/p>\n\n\n\n<ul><li>Resident (persistent over time and not readily removed by hand washing)<\/li><li>Transient (recently acquired from another source)<\/li><li>Important microorganisms are \u00e0 S. aureus \u2013 Klebsiella &#8211; Serratia.<\/li><li>Other less common organisms are \u00e0 antibiotic resistant enterococci &#8211; C. difficile &#8211; Corynebacterium diphtheriae \u2013 candida albicans &#8211; RSV &#8211; Rhinoviruses<\/li><\/ul>\n\n\n\n<p><strong>From the patient\u2019s environment<\/strong><\/p>\n\n\n\n<ul><li>Becomes contaminated with bacteria carried by a patient<\/li><li>Includes &#8211; VRE &#8211; MRSA &#8211; P. aeruginosa &#8211; C. difficile<\/li><\/ul>\n\n\n\n<p><strong>Infection in operating theater<\/strong><\/p>\n\n\n\n<ul><li>Most infections arise from the patient\u2019s own flora<\/li><li>The remainder are acquired mainly from staff in OT<\/li><\/ul>\n\n\n\n<p><strong>From equipment<\/strong><\/p>\n\n\n\n<p>Patients with impaired immunity<\/p>\n\n\n\n<ul><li>Adhesive plaster contaminated with \u2013 Rizopus<\/li><li>Unsterile wooden tongue depressors- Rizopus<\/li><li>Bed pans and urinals &#8211; C. difficile &#8211; antibiotic resistant GNB<\/li><li>Rectal thermometers &#8211; salmonellae \u2013 enterococci<\/li><li>Fiberoptic endoscopes &#8211; Salmonella &#8211; P. aeruginosa &#8211; M. tuberculosis &#8211; H. pylori \u2013 hepatitis B ( rarely )<\/li><\/ul>\n\n\n\n<p><strong>Infection by inoculation<\/strong><\/p>\n\n\n\n<ul><li>Infrequent in developed world &#8211; introduction of single-use&nbsp; disposable needles &#8211; satisfactory sterilization of surgical instruments<\/li><li>Risk of infections still persist in situations like<ul><li>transmitted by <strong>blood transfusion or<\/strong> tissue donation \u00e0 Risk of transmission of 3 most important agents \u2013 <strong>hepatitis B, C and HIV<\/strong><\/li><\/ul><ul><li>accidental injury from contaminated sharp instruments<\/li><\/ul><ul><li>contaminated blood<\/li><\/ul><ul><li>contaminated infusion fluids<\/li><\/ul><\/li><li>Infection from contaminated infusion fluid<ul><li>&nbsp;<strong>TPN fluids<\/strong> such as protein hydrolysate with or without dextrose, readily support the growth of organisms, particularly &#8211; <strong>Klebsiella &#8211; Enterobacter \u2013 Candida spp.<\/strong><\/li><\/ul><\/li><\/ul>\n\n\n\n<p><strong>Ventilator-associated pneumonia<\/strong><\/p>\n\n\n\n<ul><li>Mortality rate: 6-14%<\/li><li>Risk factors include<ul><li>Events that increase colonization by potential pathogens<\/li><\/ul><ul><li>Those that facilitate aspiration of oropharyngeal contents&nbsp; into the lower respiratory tract \u2013<\/li><\/ul><ul><li>Those that reduce host defence mechanisms in the lung and permit overgrowth of aspirated pathogens<\/li><\/ul><\/li><\/ul>\n\n\n\n<p><strong>Infection associated with indwelling medical devices<\/strong><\/p>\n\n\n\n<ul><li>The predominating bacteria are &#8211; CoNS, particularly S. epidermidis &#8211; S. aureus &#8211; Corynebacteria &#8211; Propionibacteria &#8211; Streptococci \u2013 Yeasts and filamentous fungi<\/li><li>Intravascular cannulae<\/li><li>Intravascular grafts: \u00e0Cardiac valve prosthesis<\/li><li>Joint prosthesis &#8211; S. aureus &#8211; CoNS &#8211; Enterobacteria &#8211; Streptococci ( mainly enterococci )<\/li><\/ul>\n\n\n\n<p><strong>Air-borne spread<\/strong><\/p>\n\n\n\n<p>Effectiveness of this route depends on<\/p>\n\n\n\n<ul><li>number of microorganisms present<\/li><li>degree of dispersal &#8211; survival and retention of pathogenicity by the microorganism in the air or environment \u2013<\/li><li>sizeof the infecting dose &#8211; local and general susceptibility of the persons exposed<\/li><\/ul>\n\n\n\n<p><strong>Tuberculosis<\/strong><\/p>\n\n\n\n<ul><li>Air borne spread can occur by transfer of Very few microorganisms<\/li><li>Only patients&nbsp; with smear positive pulmonary tuberculosis&nbsp; are regarded as constituting an infection risk and require single room isolation<\/li><\/ul>\n\n\n\n<p><strong>Pneumococcal infection<\/strong><\/p>\n\n\n\n<ul><li>Most infection by S pneumoniae is endogenous<\/li><li>Diagnosed by Gram stain of sputum- advisable to isolate patients for the first 24 h of treatment<\/li><li>Protection of vulnerable patients with polyvalent vaccine becomes more important as resistance increases<\/li><\/ul>\n\n\n\n<p><strong>Meningococcal infection<\/strong>&nbsp;<\/p>\n\n\n\n<ul><li>Uncommon \u2022 Isolation for first 48 h of treatment is advisable<\/li><li>Among staff, only those who have had close contact with the&nbsp; patient need to be offered prophylactic antibiotics<\/li><\/ul>\n\n\n\n<p><strong>Viral infection<\/strong> \u2022 Chicken pox \u2022 Measles \u2022 Influenza \u2022 Respiratory syncitial virus(RSV) \u2022 Small round structured viruses(SRSV) &#8211; noroviruses<\/p>\n\n\n\n<p><strong>Fungal infection<\/strong> \u2022 Dispersal by spores\u2013 most filamentous fungi \u2022 Only Aspergillus spp. Have been shown to be a significant cause&nbsp; of air borne infection &#8211; after cardiac surgery &#8211; in immunosuppressed patients \u2022<\/p>\n\n\n\n<p><strong>Infections associated with water<\/strong><\/p>\n\n\n\n<p>Legionnaires\u2019 disease \u00e0 Air cooling towers \u00e0 Source of infection<\/p>\n\n\n\n<p><strong>Infection acquired from food<\/strong> \u2022 Salmonella infections- poultry, eggs \u2022 Clostridium perfringens\u2013 meat \u2022 Can be a source of antibiotic-resistant bacteria &#8211; P. aeruginosa \u2013 Escherichia coli \u2013 Klebsiella spp.<\/p>\n\n\n\n<p><strong>Hospital Infections at various body sites<\/strong><\/p>\n\n\n\n<ul><li>Urinary tract<ul><li>40-45% of nosocomial infections<\/li><\/ul><ul><li>Associated with &#8211; urethral catheterization &#8211; cystoscopy &#8211; transurethral prostatectomy<\/li><\/ul><\/li><li>Nosocomial pneumonia<ul><li>15\u201320% of nosocomial infections<\/li><\/ul><ul><li>Almost all cases are caused by aspiration of endogenous or hospital-acquired oropharyngeal (and occasionally gastric) flora<\/li><\/ul><ul><li>Early-onset nosocomial pneumonia (within the first 4 days of hospitalization) &#8211; Streptococus pneumoniae &#8211; Haemophilus species<\/li><\/ul><ul><li>Late-onset pneumonias &#8211; S. aureus &#8211; P. aeruginosa &#8211; Enterobacter species &#8211; Klebsiella pneumoniae &#8211; Acineto bacter<\/li><\/ul><\/li><li>Surgical site infections<ul><li>0.5-15% of HAI<\/li><\/ul><ul><li>A cause of morbidity, prolonged hospital stay<\/li><\/ul><ul><li>S.aureus( MRSA )- dominating species<\/li><\/ul><\/li><\/ul>\n\n\n\n<p><strong>Infection after cataract surgery<\/strong> has declined \u2022 Endophthalmitis- following surgery, penetrating trauma \u2022 Keratoconjunctivitis caused by P. aeruginosa \u2022 Epidemics caused by adenovirustype8 \u2013 speed by instruments, hands of staff \u2022 Hospital acquired bacterial conjunctivitis-in neonatal units<\/p>\n\n\n\n<p>Peritoneum<\/p>\n\n\n\n<ul><li>Peritonitis is one of the classical association of surgery<\/li><li>Peritoneal dialysis is often complicated by peritoneal infection by GNB<\/li><\/ul>\n\n\n\n<p>Burns<\/p>\n\n\n\n<ul><li>Suitable site for bacterial multiplication<\/li><li>S. aureus and P. aeruginosa-most common isolates \u2022 Enterobacteria \u2022 Other gram negative bacilli such as acinetobacter<\/li><\/ul>\n\n\n\n<p><strong>Hospital Infections at extremes of life<\/strong><\/p>\n\n\n\n<p>How are these different\u2026? \u2022 Immunocompromised states \u2022 Hospital infection and infection control is often neglected &#8211; Declining defenses \u2013 Multiple underlying chronic diseases &#8211; Long stay at hospitals<\/p>\n\n\n\n<p>Neonatal units \u2022 Underdeveloped defenses, lack of normal flora (particularly in premature babies) \u2022 Ill babies require much handling by staff \u2022 CAUTION: &#8211; MRSA &#8211; Klebsiella &#8211; P. aeruginosa &#8211; Serratia &#8211; S. epidermidis<\/p>\n\n\n\n<p><strong>Hospital acquired infections Management and control<\/strong><\/p>\n\n\n\n<ul><li>a well-conducted surveillance and prevention program may significantly reduce HAI and associated costs<\/li><li><strong>Identification of high-risk population &#8211;<\/strong> Burns patients \u2022 Immunodeficient patients \u2022 Transplant recipients \u2022 Chronically debilitated patients \u2022 Major surgery \u2022 Ventilator support \u2022 Indwelling catheters \u2022 Prolonged ICU stay (&gt;3 days) \u2022 Old age \u2022 Frequent blood transfusion<\/li><\/ul>\n\n\n\n<ul><li>Isolation \u2022 Keep the patient away from potential sources of infection \u2022 Assess the need for isolation \u2013 Neutropenia and immunological disorder \u2013 Burns \u2013 Diarrhea \u2013 Skin rashes \u2013 Known communicable disease \u2013 Carriers of an epidemic strain of bacterium \u2022 Identify the type of isolation \u2013 Protective isolation \u2013 Source isolation<\/li><\/ul>\n\n\n\n<ul><li>Isolation rooms should have: \u2013 Tight-fitting doors \u2013 Glass partitions for observation \u2013 Negative -pressure (for source isolation) ventilation \u2013 Positive- pressure (for protective isolation) ventilation<\/li><\/ul>\n\n\n\n<ul><li>Identification of diseases at an early stage<\/li><li>Treatment<\/li><li>Periodic surveillance<\/li><li><strong>Observing hand hygiene<\/strong> &nbsp;&#8211; Hands are the most common vehicle for transmission of organisms \u2022 Single most effective means of preventing the horizontal transmission of infections among hospital patients and health care personnel<\/li><\/ul>\n\n\n\n<ul><li>Strategies to reduce VAP, CAUTI \u00e0 Designated infection control team(s) *VAP: ventilator associated pneumonia *CAUTI: catheter associated urinary tract infection<\/li><\/ul>\n\n\n\n<ul><li><strong>Strategies to reduce UTI \u2022<\/strong> Catheters only for appropriate indications \u2022 Closed drainage system \u2022 Unobstructed urine flow \u2022 Changing indwelling catheters at fixed intervals is not recommended \u2022 Remove the catheter when it is no longer needed<\/li><\/ul>\n\n\n\n<ul><li><strong>Strategies to reduce VAP \u2022<\/strong> Avoid intubation whenever possible \u2022 Prefer oral intubations to nasal \u2022 Keep head elevated at 30\u00b0 \u00ad \u00ad45\u00b0 in the semi\u00adrecumbent position \u2022 Daily oral care with chlorhexidine solution \u2022 Routine change of ventilator circuits is not required \u2022 Prefer endotracheal tubes with a subglottic suction port \u2022 Closed endotracheal suction systems are better \u2022 Periodically drain and discard any condensate<\/li><\/ul>\n\n\n\n<ul><li><strong>Strategies to reduce CRBSI<\/strong> \u2022 Avoid femoral route for central venous cannulation, prefer upper extrimity \u2022 Maximal sterile barrier precautions, and a sterile full\u00adbody drape while inserting CVCs \u2022 Clean skin usually with 2% chlorhexidine with 70% ethanol \u2022 Chlorhexidine\/silver sulfadiazine or minocycline \/ rifampin impregnated CVCs \u2022 Ultrasound\u00ad guided insertion \u2022 2% chlorhexidine wash daily for skin cleansing<\/li><\/ul>\n\n\n\n<p><strong>Environmental factors<\/strong><\/p>\n\n\n\n<ul><li>High \u00adquality cleaning and disinfection of all patient \u00adcare areas, bedrails, bedside tables, doorknobs and equipment<\/li><li>Surface cleaning (walls) twice weekly, floor cleaning 2\u00ad\u00ad3 times\/day and terminal cleaning (patient bed area) after discharge or death<\/li><li>Situated close to the operating theater and emergency department for easy accessibility, but should be away from the main ward areas<\/li><li>Central air\u00ad conditioning systems with appropriate filters, air should be filtered to 99% efficiency down to 5 \u03bcm<\/li><li>Isolation facility should be with both negative\u00ad and positive\u00ad pressure ventilations<\/li><li>Adequate space around beds is ideally 2.5\u00ad\u00ad3 m<\/li><li>Adequate number of washbasins with alcohol gel dispensers<\/li><\/ul>\n\n\n\n<p>Organisational and administrative measures \u2022 Better patient to nurse ratio in the ICU \u2022 Controlling traffic flow to and from the unit to reduce sources of contamination \u2022 Waste and sharp disposal policy \u2022 Education and training for ICU staff \u2022 ICU protocols and SOPs \u2022 Audit and surveillance of infections and infection control practices \u2022 Infection control team (multidisciplinary approach) \u2022 Antibiotic stewardship \u2022 Vaccination of health care personnel<\/p>\n\n\n\n<p>Infection Prevention in Burns Patients \u2022 Burn wounds can provide optimal conditions for colonization, infection and transmission of pathogens \u2022 Source of infection: staphylococcistaphylococci located deep within sweat glands and hair follicles \u2022 Routine surveillance cultures: \u2013 Early identification of organisms \u2013 Monitor the effectiveness of current wound treatment \u2013 Guide an appropriate antibiotic therapy \u2013 Weekly \u2022 Stringent isolation guidelines \u2022 Antibiotic prophylaxis: role of topical antimicrobials &gt; systemic antibiotics<\/p>\n\n\n\n<p>Early enteral feeding: increases circulation to the bowel, thereby decreasing ischemia post \u00adinjury and the translocation of bowel flora \u2022 Human tetanus immunoglobulin (250\u00ad\u00ad500 IU)<\/p>\n\n\n\n<p>Immuno\u00adcompromised and Transplant Patients \u2022 Greatest risk of infection caused by airborne or waterborne microorganisms \u2022 Neutropenic for prolonged periods (ANC &lt; 500 cell\/cumm) \u2022 Opportunistic infections<\/p>\n\n\n\n<p>Opportunistic infections \u2013 Exogenous acquisition of a particularly virulent pathogen, e.g. meningococcal meningitis or pneumococcal pneumonia \u2013 Reactivation of an endogenous latent organism, eg, herpes zoster virus, Mycobacterium tuberculosis \u2013 Endogenous invasion of a normally commensal or saprophytic organism<\/p>\n\n\n\n<p>Post \u00adtransplant period 1. During the first month after transplantation: \u2013 &gt;95% of the infections are due to bacterial or candida infection of the surgical wound, vascular access, endotracheal tube, or drainage catheters 1. During the period 1\u00ad\u00ad6 months after transplantation: 1.Two classes of infection : Infections caused by immunomodulatory viruses and infections caused by opportunistic pathogens such as Pneumocystis carinii, Listeria monocytogenes and Aspergillus species \u2022 In the late period: 1.Cryptococcus neoformans, P. carinii and L. monocytogenes<\/p>\n\n\n\n<p>76. Monitoring of Infection Control<\/p>\n\n\n\n<p>Antimicrobial Stewardship<\/p>\n\n\n\n<ul><li>Multidisciplinary antimicrobial stewardship program<\/li><li>Antibiotic stewardship refers to a set of coordinated strategies to improve the use of antimicrobial medications with the goal of enhancing patient health outcomes, reducing resistance to antibiotics, and decreasing unnecessary costs<\/li><li>Infectious disease physician and a clinical pharmacist with infectious disease training<\/li><li>Clinical microbiologist, an information system specialist, an infection control professional and hospital epidemiologist<\/li><li>Close collaboration between the antimicrobial stewardship team, microbiology lab, hospital pharmacy and infection control team<\/li><\/ul>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Nosocomial Infection Hospitals bring together vulnerable hosts &nbsp;\u00e0 Subject them to particular risk of infection \u00e0 Cause of morbidity and mortality \u00e0 &nbsp;Limits&nbsp; effectiveness, adds greatly to cost. Hospital-acquired infection (HAI) ( nosocomial infection) An infection acquired in hospital by a patient who was admitted for a reason other than that infection . or An[&#8230;]\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","footnotes":""},"categories":[3],"tags":[],"_links":{"self":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts\/690"}],"collection":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/comments?post=690"}],"version-history":[{"count":0,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts\/690\/revisions"}],"wp:attachment":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/media?parent=690"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/categories?post=690"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/tags?post=690"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}