Hospital-acquired infections are infections acquired by a patient or staff member in a hospital that produce clinical symptoms. Because infections have a certain incubation period, hospital-acquired infections also include patients who become infected in the hospital and develop the disease only after they are discharged.
Second, the classification of hospital infections
Based on the different sources of infection, hospital infections are divided into:
(a) endogenous infection (self-infection)
The immunocompromised patients by their own normal flora caused by the infection. That is, the patient has been a pathogen carrier before the occurrence of hospital infection, when the body resistance is reduced to cause self-infection.
(2) exogenous infection
refers to infections caused by exogenous flora brought from others in the environment. Including:
1. Cross infection
Direct infection caused by the acquisition in the hospital or others (patients, carriers, staff, visitors, chaperones).
2. Environmental infections
Infections caused by contaminated environment (air, water, medical equipment and other items). Such as due to the operating room, air pollution caused by the patient's postoperative incision infection, syringe sterilization is not strict caused by the epidemic of hepatitis B and so on.
Three common hospital infections
(A) lung infection
Lung infection often occurs in some chronic serious impact on the patient's defense mechanism of the disease, such as cancer, leukemia, COPD, or tracheotomy, tracheal catheterization and other patients. Judgment of lung infection is mainly based on clinical manifestations and X-ray fluoroscopy or photographs, and its incidence accounts for about 23.3% to 42% of hospital-acquired infections. Lung infections are a threat to critically ill patients, immunosuppressed patients, and patients with weakened immunity, with a mortality rate of 30%-50%.
(2) urinary tract infection
Patients who do not have symptoms of urinary tract infection at the time of admission, but develop symptoms (fever, dysuria, etc.) after 24 hours during their hospitalization, and have bacterial growth in urine culture, or have no symptoms, but the white blood cells in the urine specimen are more than 10 / ml, and the bacteria are more than 105 / ml can be judged to be a urinary tract infection. China's statistics, the incidence of urinary tract infections in hospital infections accounted for about 20.8% to 31.7%,
66% to 86% of the occurrence of urinary tract infections related to the use of catheters.
(C) Wound infection
Wound infection includes wound infection in surgical and traumatic events, and the judgment of wound infection mainly depends on whether there is an inflammatory reaction or the appearance of pus in the wound and the nearby tissues, and more precisely, the bacterial culture. Statistically the incidence of wound infection is about 25% of hospital-acquired infections.
(D) viral hepatitis
Viral hepatitis can be transmitted not only in healthy people, but also in patients. Viral hepatitis can be categorized into five types: type A, type B, type C, type D, and type E. The most common types of viral hepatitis are A, B, C, D and E.
The source of hepatitis A and hepatitis E is the patient and asymptomatic infected people, transmitted through the digestive tract. The patient discharged feces with virus, without disinfection, contaminated water or food, people mistakenly
eat unboiled water or uncooked food and be infected, that is, fecal-oral transmission.
Hepatitis B, hepatitis C, hepatitis D, the source of infection is the patient and virus carriers, the virus exists in the blood and various body fluids, infectious blood can be infected through the skin, mucous membranes of the tiny damage, but also through the vertical transmission from mother to child, or through the transfusion of blood products, close sexual contact and infection.
(E) skin and other parts of the infection
Patients in the hospital during the skin or subcutaneous tissue pus, various dermatitis, bedsore infections, bacteremia, intravenous catheter and needle puncture site infection, endometrial infection, intra-abdominal infection.
Hospitalized patients who have endotracheal intubation, multiple surgeries or prolonged surgery, indwelling catheterization, the application of chemotherapy, radiotherapy, immunosuppressive agents, as well as geriatric patients should be considered as the key object of the prevention of hospital-acquired infections.
Four, hospital infection factors
(A) subjective factors
Medical staff on hospital infections and its harm of insufficient knowledge; can not strictly implement the aseptic technology and disinfection and isolation system; the hospital rules and regulations are incomplete, there is no sound outpatient and emergency room pre-screening, triage system, inpatient hospitals do not have a hospitalization system of hygiene and disposal, resulting in the dissemination of the source of infection. In addition, there is a lack of monitoring of the effectiveness of disinfection and sterilization, which does not effectively control the occurrence of hospital-acquired infections.
(B) objective factors
1. invasive means of diagnosis and treatment increased
According to statistics, the United States each year due to the use of medical devices and infections accounted for 45% of hospital infections. Such as endoscopes, urinary catheters, arterial catheters, tracheotomy, tracheal intubation, inhalation devices, organ transplantation, dental drills, blood collection needles, suction vessels, monitoring instrument probes and other invasive diagnostic and treatment means, not only the outside world of microorganisms imported into the body, but also damage the body's defense barriers, so that pathogens are easy to invade the body.
2. The use of immune-suppressing treatments
Because of the need for treatment, the use of hormones or immunosuppressants, chemotherapy, radiotherapy, resulting in a decline in the patient's own immune function and become susceptible.
3. The development and popularization of a large number of antibiotics
The application of a variety of antibiotics in the course of treatment or the centralized use of a large number of antibiotics, so that the patient's body of the normal bacterial flora imbalance, drug-resistant strains of bacteria, resulting in prolonged course of the disease, the chance of infection increased.
4. susceptible patients increased
With the progress of medical technology, some incurable diseases in the past can be cured or prolong the survival time, so the proportion of hospitalized patients with chronic diseases, malignant diseases, the proportion of elderly patients increased, and the resistance of these patients to infections is quite low.
5. Serious environmental pollution
Hospitals due to infectious agents, so the pollution of the environment is also serious. Among them, the most serious pollution is the infected patient's ward, the toilet pollution is also very serious, flush toilet every pumping water may provoke a large number of microbial aerosols. Public **** supplies in the ward, such as sinks, bath tubs, commodes, carts, mops and rags, are also often contaminated.
6. Failure to place necessary restrictions on visitors
When reasonable and necessary restrictions on visitors are relaxed, the likelihood of pathogenic bacteria being brought into the hospital by visitors or chaperones increases.
V. Prevention and control of hospital-acquired infections
The causes of hospital-acquired infections are many and varied, but as long as management is strengthened and effective measures are taken, nearly 2/3 of hospital-acquired infections can be prevented.
(A) improve the hospital building and layout
Hospital building layout is reasonable or not on the prevention of hospital infections is crucial. Infectious disease rooms, ultra-clean wards, operating rooms, guardianship rooms, observation rooms, visiting and reception rooms, supply rooms, laundry rooms, kitchens, etc., from the point of view of infection prevention, in order to prevent the proliferation of bacteria and the spread of disease, in the equipment and the layout of the special requirements should be.
(2) strict implementation of rules and regulations
Systems are the summary of people's experience in long-term work practices and the basis for dealing with and checking the work. Including disinfection and isolation system, aseptic technology operating procedures and visitation system. Isolation is aimed at limiting contamination to the smallest possible extent, and is one of the most important measures to prevent hospital infections. Aseptic operating procedures are medical regulations that must be followed by health care workers throughout the process of diagnosis and treatment. Every health care worker should be from the hospital infection, to protect the patient's health from the strict implementation of the system, routine and implementation of the rules, and advise patients and visitors *** with compliance.
(C) good disinfection and sterilization
Disinfection and sterilization is an effective measure to control hospital-acquired infections.
(D) strengthen the cleanliness and hygiene work
Cleanliness and hygiene work includes dust, dirt wiping and removal, but also includes the prevention of mosquitoes, flies, cockroaches, rodents and so on.
When carrying out cleaning and sanitation work, care must be taken not to raise dust and avoid spreading pollution. Hospitals should not use brooms and dusters, mopping the head of the best can be removed in order to disinfect. Ward cleaning work, it is appropriate to carry out immediately after the pollution. The order should be started by the less contaminated wards, gradually into the more seriously contaminated areas, and finally deal with the patient's public **** activities. Medical staff workplace should also be clean and sanitary cleaning.
(E) to take reasonable diagnostic and therapeutic methods
The use of antimicrobial drugs to be targeted, the application of suppression of immunotherapy to take appropriate protective measures, such as the first treatment of chronic foci to prevent their own infections, regular checks of white blood cell dynamics and other monitoring, providing drug prevention. Diagnostic treatment that is easy to introduce microorganisms into the body should be effectively disinfected, sterilized, and strictly aseptic technical operation.
(F) timely control of the prevalence of infection
Control of the prevalence of infection mainly includes the search for the source of infection and the way to take appropriate isolation and disinfection measures.
(VII) to carry out monitoring of hospital infections
The purpose of monitoring hospital infections is to obtain first-hand information through monitoring, analyze the causes of hospital infections, to find the weak links, to provide a basis for effective measures to be taken, and through the monitoring to evaluate the effectiveness of various measures. The main content of the monitoring includes: environmental pollution monitoring, sterilization effect monitoring, disinfection pollution monitoring, special ward monitoring (such as burns, urology wards, operating room, guardianship room, etc.), bacterial strain resistance monitoring, cleanliness and hygiene monitoring, infectious agent monitoring, rules and regulations implementation monitoring. Surveillance should be carried out as a routine, on a regular basis, at regular intervals, and for regular programs. Records of infections are required to be detailed and specific, and are analyzed by regular statistics on a ward-by-ward basis.
(viii) improve staff hygiene and health conditions
All hospital staff should have regular health checkups, and if they are unwell or suspected of infectious diseases, they should be reported immediately so that appropriate measures can be taken and the relevant vaccines can be injected as needed, and passive immunization or drug prophylaxis can be carried out as well when necessary.
Medical staff should also do a good job of personal protection, one is to prevent the germs to themselves or take out of the ward; the second is to prevent the germs to the susceptible person in the room. The main personal protection is to wear personal protective equipment (clothing, hats, shoes, gloves, masks) and hand washing and disinfection.