Healthcare associated infections Dr Sushela devi

Learning Outcomes Define HAI Describe the development, transmission, predisposing factors of HAI Outline the pathogenesis of commonly encountered infections Briefly describe the prevention of HAI

Healthcare associated infections Synonymous with: Hospital associated infections Hospital acquired infections Nosocomial infections Infections that are acquired during the patient’s stay in hospital Acquired in hospitals as a result of healthcare interventions or while receiving treatment for other conditions within a healthcare setting

Major types of infection Surgical site infection/sepsis(SSI/SSS) Central line associated bloodstream infection(CLA-BSI) Catheter-associated urinary tract infection (CA-UTI) Ventilator-associated pneumonia (VAP)

Development High prevalence of pathogens High prevalence of compromised hosts Patients with similar susceptibilities in an enclosed environment Transmission is from patient to patient Environment to patient Staff to patient Colonisation of patient’s skin, respiratory tract and genitourinary tract

Commonly encountered infections Bacterial Fungal Viral Parasitic Based on: Patient factors, Healthcare environment, therapeutic/diagnostic procedures Urinary tract infections, pneumonia which may be ventilator associated, surgical site infection, bloodstream infections, ear, nose and throat infections, gastrointestinal infections, skin and soft tissue infections

Predisposing factors A. Patients at special risk: Immunological status of host Age-neonates and elderly Obesity: less blood in adipose tissue Diabetes mellitus Malnutrition Burns Neoplasms

B. Therapeutic procedures Antibiotic administration-alter the normal flora, select for multi drug resistant strains and encourage the growth of fungi Sometimes contaminated drugs and solutions may be used

2.Immunosuppresive therapy Radiation- which will lead to decreased bone marrow formation, macrophage function and antibody production. Radiation will also damage normal cells

3.Invasive devices/foreign bodies IV line Urinary catheter Suture Implant Prosthesis

C. Diagnostic procedures Instruments/devices Not properly disinfected Not properly sterilised

Bacterial infections Urinary tract infections- Catherisation Catheter associated urinary tract infections CAUTI account for 80% of hospital acquired infections For patients with an indwelling urinary catheter it is important to maintain a closed drainage system to reduce the risk of infection Influenced by duration and by handling of patients.

Endogenous infection- E.coli, Klebsiella, Proteus, Enterobacter Cross infections- Pseudomonas ( contaminated devices/solutions) and through hospital staff (Serratia and Proteus)

Bacteremia Predisposing factors Therapeutic /diagnostic procedures Develops through various invasive procedures or it may be secondary infections from other anatomical sites Organisms that cause this infection depends upon the site and the procedure performed Skin flora- Staphylococcus aureus, Serratia, Enterococci, Staphylococcus epidermidis

IV therapy Replace fluids Administration of medication

Urinary catherisation- Escherichia coli Cardiac surgery- Staphlococcus aureus, Staphylococcus epidermidis Bowel/ obstetric surgery- Bacteroides, Enterococci

Respiratory Infections 15% of healthcare associated infections Pneumonia is the common infection Acquired through use of ventilator, tracheostomy and even inhalation therapy Causal organisms-Klebsiella, Pseudomonas aeroginosa. Infection may occur 24hours after intubation in about 50% of patients

Surgical wound infections Varies from hospital to hospital Type of surgery Duration of surgery Presence or absence of drainage tube Nature of the wound- clean wound-1-3%, dirty wound-more than 30%-60% Causal organisms- Staphylococcus aureus, Serratia, Escherichia coli, Proteus, Pseudomonas

Intensive care Unit Infections Greatest rate of infections Patients are usually seriously compromised Patients are on medical/surgical treatment and may be subjected to invasive procedures Neonatal infections-Staphylococcus aureus, Klebsiella and Pseudomonas Burn infections-Staphylococcus aureus, Pseudomonas Predisposing factors- severe burns, neonates and children (under fives) and the elderly

Viral Infections Hepatitis B/C infections-through contaminated blood or blood products Contaminated instruments Cyotmegalovirus (CMV) infections- Renal transplant patients Herpes simplex infections Respiratory syncytial virus-acute bronchitis/pneumonia in infants Influenza virus Rotavirus

FUNGAL Infections Candida albicans-this is a commensal in the mouth, GI tract and vagina Prolonged antibiotic treatment Invasive procedures Aspergillus fumigatus-respiratory infections, endocarditis especially in those with prostheses Pneumocystis jirovecii-pneumonia in the immunosuppressed

Parasitic Infections Infrequent Sarcoptes scabei-scabies

Prevention of HAI Risk stratification Reduce person to person transmission Prevention of transmission from environment, health care personnel Using proper infection control practices Vaccination where appropriate

Prevention of Urinary tract infections Avoid unnecessary catherisation Avoid indwelling catheters Sterile closed drainage system Aseptic technique during insertion Drain collection bag regularly Monitor bacteruria

Prevention of IV-therapy associated infection Proper disinfection at insertion site Change IV line every hours Check infusion for contamination Maintain asepsis

Prevention of I.C.U. infections Control the underlying disease condition Isolate patients Barrier nursing-The term "barrier nursing" is given to a method of nursing care when caring for a patient known or thought to be suffering from a contagious disease such as open pulmonary tuberculosis. The nurses wear gowns, masks, and sometimes rubber gloves, and they observe strict rules that minimize the risk of passing on infectious agents. All equipment and utensils used to care for the patient are immediately placed in a bowl of sterilizing solution, and attending nurses observe surgical standards of cleanliness in hand washing after they have been attending the patient. Bedding is carefully moved in order to minimize the transmission of airborne particles, such as dust or droplets that could carry contagious material, and is cleansed in special facilities that include the use of steam heat for sterilization. Proper aseptic technique Routine bacterial monitoring of patient and equipment

Prevention of surgical wound infections Proper aseptic techniques Proper sterilisation of equipment Avoid indiscriminate use of antibiotics

Isolation policy Patients with extensive discharging staphylococcal lesions Carriers of virulent strains Highly susceptible patients-such as transplant patients, the immunosuppressed

HAI surveillance Infection control committee Infection Control Team Infection control programme Infection control manual Responsibility: Hospital management Health care personnel Support services

The END A note of thanks to Prof Mala Maung. I have modified some of her lecture notes for this lecture. Thank you for listening