Environmetal Health Study Resources

Environmental Health Hospital environment: Definition of hospitals: A residential establishment which provides medical care services for people suffering from a disease or injury. Function of hospitals: Intramural Function: Therapeutic, preventive, education, research. Extramural Function: Outpatient services, home care services. Physical environment of healthcare facilities: Location: The place should not be densely populated. Hospital should be elevated from the surrounding. Independent access to a street. Adequate lighting. Away from nuisance. Safe drinking water. Proper ventilation. Good drainage system. Healthcare-associated infections (HCAIs): One of the most common problems that affect healthcare facilities worldwide. According to WHO data, the prevalence of HCAIs in low and middle-income countries ranges from 5.7% to 19.1%. Definition of HCAIs: An infection that was not present at the time of admission but occurs in a patient during 48 hours after the procedure, care in a healthcare facility, or 48 hours after discharge. Types of HCAIs: Endogenous (auto-infection): Caused by organisms that are present as part of the normal flora of the patient. Exogenous (cross infection): During hospitalization, the patient comes into contact with different microorganisms, and because of that, they may become contaminated and develop an infection. The most frequent HCAIs are: Urinary tract infections (UTI) Surgical site infection Bloodstream infections Lower respiratory infection Gastroenteritis Skin infections Sources of HCAIs: The primary source of infection is the patient. Staff (doctor, nurse, healthcare provider). Instruments. Environment. Visitors. Modes of transmission: Direct transmission: a) Droplet b) Direct contact Airborne Contaminated vehicle Vector-borne transmission Indirect transmission Chain of infection: Agent: Bacteria, fungi, parasites, prions. Reservoir: People, water, food. Portal of exit: Blood, secretions, excretions, skin. Modes of transmission: Contact, droplet, physical, airborne. Portal of entry: Mucous membranes, respiratory, digestive system. Susceptible host: Immune deficiency, DM, burns, surgery, age. Prevention of HCAIs: Hand hygiene Proper use of PPE Safe injection practice Proper disinfection, sterilization, and use of instruments Proper environmental cleaning Proper waste management Apply universal precautions. Proper hand hygiene: Definition: Washing hands with soap and water for 1 min or for 40 sec. OR rubbing hands with an alcohol-based solution for 20 to 30 sec. History: 1847, Hungary, Ignaz Semmelweis (pioneer of hand hygiene). International day for hand hygiene: 15th of October When should we apply it? Before patient contact. Before a clean/aseptic procedure. After body fluid exposure/risk. After patient contact. After contact with patient surroundings. Which best? Regular soap Antimicrobial soap Alcohol-based hand rub Steps of hand hygiene (video): It is very important (7 steps). Proper use of personal protective equipment (PPE): Head Cap Goggles and Face Shield Gown and Aprons Gloves: Type: Sterile, clean, heavy. Mask: Type: N95, Protection 60%, N95, N98, FFP2, FFP3. Cover Shoes Safe injection practice: 1 needle 1 syringe Only one time For one patient Proper environmental cleaning: Cleaning means general removal of visible dust, debris, soil, and secretions, blood, or other potentially infectious material. Proper disinfection and sterilization of used instruments or equipment: Disinfection: The process of removing pathogens (but not spores) that may cause an infection. Types of disinfection: I. Concurrent disinfection: Application of disinfectants as soon as possible after the discharge of infectious material from the body of a person (e.g., disinfection of urine). II. Terminal disinfection: Application of disinfectants after the patient has been removed by death or shifted from isolation, or has ceased to be a source of infection. III. Precurrent (prophylactic) disinfection: Action taken before the use of infection (e.g., hand washing). Sterilization: The process that completely destroys or removes all microorganisms, including spores. When should we do cleaning, disinfection, and sterilization: Based on Spaulding's Classification: 1. Critical: Requires sterilization/sterile tissue, surgical instruments. 2. Semi-Critical: Requires a high level of disinfection. Includes items that contact with the skin/mucous. Cleaning first then high-level disinfection. 3. Non-Critical: Requires intermediate or low-level disinfection. Includes items that only contact intact skin. Proper waste management: Hazardous: 10-15% Non-Hazardous: 75-90% Types of hospital waste: General: Non-Hazardous. Infectious: Hazardous. Chemical: Hazardous. Radioactive: Hazardous. How to deal with hospital waste? Identification of waste: Hazardous Non-Hazardous Segregation of waste: Separation of waste type to facilitate recycling and correct onward disposal in bags or plastic bins. General waste (non-infectious & non-hazardous): Put in a green plastic bin. Hazardous (non-infectious) waste: Put in a black plastic bin, each of them has a specific logo. Hazardous (infectious) waste: Pathological (anatomical) waste: Put in a yellow plastic bin. Soiled gauze, cotton: Put in a red plastic bin. Plastics (gloves, syringes): Put in a blue plastic bin. Sharp waste: Put in a sharp box to be incinerated. Collection and transportation: By separation, the waste and then by transporting them after separation in a closed area away from internal areas, and then disposed of according to its type. Disposal: General waste: Landfill Human parts: Return back to the company if not burnt. Pharmaceutical: The land then landfill if no explosion, so incineration. There is no chlorine. Pressurized containers: Return back to the company and refill if it's empty and in good condition. Infectious & hazardous waste: In the first, we should disinfect it then incinerate it. Hazardous & non-infectious waste: Treat it, then dispose of it like radiological waste.