Nosocomial infections also known as hospital acquired infections are infections not present and without evidence of incubation at the time of admission to a healthcare setting. They become evident 48 hours after admission or 48 hours after patient is discharged.
Definition of nosocomial infections[edit | edit source]
- NI - not an infection contracted by health care personnel in the course of their profession - professional infection.
- Basic feature of NI - hospital strains have higher resistance to antimicrobials and disinfection.
- Cause of higher morbidity and mortality.
Classification of nosocomial infections[edit | edit source]
- Exogenous - the agent is introduced into the organism from outside;
- endogenous - own infectious agent from the colonized site into another system, into a wound, into serosal cavities (Blood, during surgery, invasive procedures, immunosuppressive treatment); the etiologic agent is the microflora present in the body, which is normally non-pathogenic.
According to the epidemiological point of view:
- non-specific - reflect the epidemiological situation in the catchment area of the health facility or are an indicator of the hygiene level of the facility;
- specific - a consequence of diagnostic and therapeutic procedures, their occurrence can be influenced by asepsis, sterilization, disinfection, hygiene-epidemiological regime.
According to the affected system:
- catheter - from the bloodstream;
- urinary tract infections;
- wound infections;
- genital tract;
Process of spreading nosocomial infections[edit | edit source]
- Existence of a source of the causative agent - Transmission of the causative agent by NI - Presence of a susceptible individual - Transmission of the causative agent by NI - Presence of a susceptible individual.
Source - Nosocomial agent[edit | edit source]
- Patient - his own microflora, another patient (his microflora is in saliva, on hands, in air, dust, tools, etc.).
- Health care worker - does not appreciate his own disease.
- Visitor - least serious source, control of visitors.
Forms of nosocomial infections[edit | edit source]
- Manifest - less dangerous, easily diagnosed and treatable.
- Carriage - carriers harbor and excrete infectious agents without obvious signs of disease.
Nosocomial transmission[edit | edit source]
- Direct transmission:
- presence of a source of infection and a susceptible individual;
- contact (e.g., kissing/sexual contact);
- essentially transmission by the hands of health care personnel;
- in newborns - eye infection (direct contact with the mucous membrane of the vagina);
- droplet infection;
- alimentary route - preparation of milk food in the neonatal unit.
- Indirect transmission depends on:
- the ability of the microorganism to survive outside the host body;
- the existence of a suitable medium in which the aetiological agent multiplies and with the help of which the infection is transmitted.
Most common bacterial agents of nosocomial infections[edit | edit source]
- Streptococcus pneumoniae,
- Clostridium difficile,
- Pseudomonas aeruginosa,
- Helicobacter pylori,
- Mycobacterium species,
- mycotic agents.
Mechanism of bacterial resistance[edit | edit source]
- ATBs have been used for more than 50 years.
- ATBs are a substantial part of all drug costs.
- Adequate application of ATBs - economics and spread of resistance.
- Emergence of resistance - most in ICU and ARO settings - multiple ATB applications.
Most important microorganisms: gram-positive bacteria[edit | edit source]
- MRSA - methicillin-resistant Staphylococcus aureus.
- MRCNS - methicillin-resistant coagulase-negative staphylococcus aureus.
- VISA - Staphylococcus aureus with reduced susceptibility to vancomycin.
- PRSP - Streptococcus pneumoniae resistant to PNC.
- VRE - vancomycin-resistant enterococci.
- Enterococci with high resistance to aminoglycosides.
Most important microorganisms: gram-negative bacteria[edit | edit source]
- With production of broad-spectrum β-lactamases encoded plasmidally and chromosomally (ESBL).
- With resistance to carbapenems.
- With resistance to fluoroquinolones.
- With resistance to aminoglycosides.
Resistant strains of MRSA[edit | edit source]
- Identified in 1961.
- In the US, incidence increased from 2.4% in 1975 to 30-60% after 1990.
- Scandinavia - still 1% in 1990.
- Spain and France - more than 30%.
- 1990 in Central Europe - prevalence from 1.7% to 8.7%'.
- England - from 3% in 1989 to 34% in 1998.
- Measures - isolation and compliance with a hygiene and epidemiological regime, including hand washing.
MRSA resistance in the Czech Republic[edit | edit source]
- Exact figures are not available;
- 70 hospitals have investigated invasive isolates under the EARSS (European Antimicrobial Resistance Surveillance System) project;
- MRSA incidence - 3.8% in 2000 increased to 8.8% in 2004.
Resistance is caused by[edit | edit source]
- The production of bacterial enzymes that disrupt or modify the structure of the ATB;
- Alteration of the bacterial wall - reduction of its permeability;
- modification of the target sites of ATBs;
- increased excretion of ATB from bacterial cells to prevent its intracellular accumulation.
Suppression of nosocomial infections[edit | edit source]
- Knowledge of all data and information on the emergence and spread of NN is a prerequisite;
- Data collection is integrated into the "Surveillance" programme;
- Decree 195/2005 Coll. - lists infectious diseases for which isolation in inpatient facilities is ordered and treatment is mandatory;
- Act on the Protection of Public Health and on Amendments to Certain Related Acts - 258/2000 Coll., last amended - Act No. 274/2003 Coll.
Repressive measures[edit | edit source]
- eradication of an outbreak of an already established disease;
- reporting of an outbreak of NI;
- treatment of a patient with NI, isolation;
- barrier nursing care;
- search for contacts and source of infection;
- disinfection - in the outbreak area;
- increasing the immunity of susceptible patients;
- control of the measures ordered, including thorough documentation.
Nosocomial urinary tract infections[edit | edit source]
- Account for 30-40% of UTIs;
- 60-90% - association with indwelling urinary catheter;
- 10% - urological-endoscopic intervention;
- Less costly NI, but prolonged hospitalization increases cost of treatment.
Prevention[edit | edit source]
- Always use a sterile catheter;
- thorough disinfection of the periurethral area;
- hand disinfection, use of sterile gloves;
- catheter fixation - prevention of movement in the urethra.
Surgical site infection[edit | edit source]
- Third most common NI - 14-20% CDC:
- superficial IMCHV;
- deep incisional IMCHV;
- Organ/space IMCHV.
Clinical picture of IMCHV[edit | edit source]
- serous secretions;
- purulent secretion from a small area of the wound;
- purulent secretion from the whole wound area, eventually its disintegration - dehiscence.
Prevention in the preoperative period[edit | edit source]
- The shortest possible hospitalization before surgery;
- Thorough bath and shower;
- for elective procedures, overtreat other infections;
- attention to shaving the surgical site;
- antibiotic prophylaxis.
Intraoperative prophylaxis[edit | edit source]
- Principles of asepsis and barrier nursing techniques;
- use of protective equipment by theatre staff;
- disposable drapes;
- disinfection of the surgical field site with proper exposure to disinfectant;
- precise surgical technique;
- minimizing the number of staff in the operating room;
- efficient ventilation and air conditioning in the operating room.
Postoperative interventions[edit | edit source]
- Cover the incision with a sterile dressing for 24-48 hours;
- principles of asepsis during dressings;
- Educate family and patient about proper wound care and symptoms of wound infection.
Respiratory tract - pneumonia[edit | edit source]
- 10-20% of all nosocomial infections;
- incidence in ICUs can be as high as 65% with mortality rate above 25%;
- prolong hospitalization;
- persons at risk are over 70 years of age.
Specific risk factors[edit | edit source]
- Internal- age, smoking, alcoholism, malnutrition, obesity, lung disease, severe general illness, and microbial flora of the oropharynx.
- External - length of hospitalization, immunosuppression, drug administration, thoracic and abdominal surgery, tracheotomy, ET, bronchoscopy, ventilators, nebulizers.
General principles of prevention[edit | edit source]
- maintaining proper personal hygiene and hand washing
- sterilisation of hospital equipment
- providing clean and sanitary environment
- existence of infection control team
- regular, close observation of high-risk units .e.g intensive care
- development of policies on areas such as isolation, disinfection and antibiotic usage
Links[edit | edit source]
Sources[edit | edit source]
- KOLEKTIV AUTORŮ,. Základy ošetřování nemocných. 1. vydání. Praha : Karolinum, 2005. 145 s. ISBN 80-246-0845-6.
- MIKŠOVÁ, Z, et al. Kapitoly z ošetřovatelské péče I.. 2. vydání. Praha : Grada, 2006. 248 s. ISBN 80-247-1442-6.
- MIKŠOVÁ, Z, et al. Kapitoly z ošetřovatelské péče II.. 2. vydání. Praha : Grada, 2006. 171 s. ISBN 80-247-1443-4.
- RICHARDS, A a S EDWARDS. Repetitorium pro zdravotní sestry. 1. vydání. Praha : Grada, 2004. 376 s. ISBN 80-247-0932-5.
- ROZSYPALOVÁ, M a A ŠAFRÁNKOVÁ. Ošetřovatelství I., II.. 1. vydání. Praha : Informatorium, 2002. 239 s. ISBN 80-86073-97-1.
- WORKMAN, B a C., L. BENNETT. Klíčové dovednosti sester. 1. vydání. Praha : Grada, 2006. 259 s. ISBN 80-247-1714-X.
- MANDAL, BK. Lecture Notes : Infectious Diseases. 6th edition. Wiley-Blackwell, 2004. 280 pp. ISBN 978-1-4051-0820-1.
References[edit | edit source]
- Ayesha Mirza, MD Assistant Professor, Pediatric Infectious Diseases, University of Florida College of Medicine Jacksonville- Hospital-acquired infections. January 5th 2012 (http://emedicine.medscape.com)