Hospital isolation rooms

For unidirectional rooms the placement of inlet, source, and person is as important as when using exhaust hoods. For hospital isolation rooms, it is not only the inlet, outlet, and the person who influences the contaminant concentration the design of the room and the handling of the room s door are also important. 

There are many different combinations of supply inlets and exhaust enclosures, where the system has been designed as a whole. Two of these enclosures are described in some detail abrasive blasting rooms with a person working inside the enclosure, and hospital isolation rooms. 

It should be noted that the primary purpose of the ventilation systems described for abrasive blasting rooms and hospital isolation rooms is to prevent or minimize exposure to hazardous substances in those persons working outside the blasting or isolation room. The ventilation system may also reduce exposure for workers inside these rooms, but often the reduction is not sufficient to eliminate the need for respiratory protection. 

Infectious patients present a difficult challenge when trying to protect health care workers. These patients must be isolated from the health care workers as well as from the other patients in the hospital. Special isolation rooms are used for this purpose. These rooms are generally used for isolation of infectious tuberculosis (TB) patients, but could be used for patients with other airborne-transmitted diseases. In the United States, there were 22 812 new cases of tuberculosis in 1993, equal to 8.7 per 100 000 population. This represents a 2.8% increase since 1985, following a 6-7% annual decline from 1981-1984.Several studies have documented higher than expected tuberculin skin test (TST) conversion rates in hospital personnel.The National Institute for Occupational Safety and Health " reports that multiple-drug-resistant (MDR) strains of TB have been reported in 40 states and have caused outbreaks in at least 21 hospitals, with 18-35% of exposed workers having documented TST conversions. 

The principle behind all of the conditions is to use the direction of airflow to prevent contaminated air from traveling out of the isolation room to other areas of the hospital. The direction of the airflow is controlled by creating and maintaining a pressure differential between the space containing the contaminated air and adjacent areas. Additionally, sufficient air must flow rlirough the space to dilute the contaminant concentration to as low as feasible. 

Survey major metropolitan hospitals on supplies of antidotes, drugs, ventilators, personal protective equipment, decontamination capacity, mass-casualty planning and training, isolation rooms for infectious disease, and familiarity of staff with the effects and treatment of chemical and biological weapons. 

Chicago showed that lack of mechanical makeup air resulted in contaminated air reentering the hospital, and therefore these rooms were not isolated from adjacent spaces. 

The patient suspected of having active tuberculosis disease must be isolated until the diagnosis is confirmed and he or she is no longer contagious. Often, isolation takes place in specialized negative pressure hospital rooms to prevent the spread of tuberculosis. 

All patients in whom smallpox is suspected should be placed in strict respiratory isolation in negative pressure rooms. Contacts of patient should be vaccinated and placed under surveillance. Isolated in-home or nonhospital facilities are preferable, due to the high risk of transmission of smallpox via aerosol within hospital environments (Henderson et al., 1999). 

In either a hospital or outpatient setting, place patients suspected of having VHP in a private room and initiate standard, contact, and droplet precautions. The CDC Web site has a description of these precautions at http //www.cdc. gov/ncidod/dhqp/gl isolation.html. 

Hospitalization of patients will reduce exposure of family members and the public, but will increase occupational doses to hospital staff. There is also a potential hazard that the patient can have an antibiotic-resistant infection. Isolation in a special ward room may also be a psychological burden to some patients and their family members. Cost-benefit analysis should be considered, including monetary costs as well as psychological and other health consequences (Table 100.8). 

The unique facilities available at USAMRIID also include a 16-bed clinical research ward capable of BL-3 containment, and a 2-bed patient care isolation suite where ICU-level care can be provided under BL-4 containment. Here, healthcare personnel wear the same positive-pressure suits as are worn in BL-4 research laboratories. The level of patient isolation required depends on the infecting organism and the risk to healthcare providers. Patient care can be provided at BL-4. There is no patient-care category analogous to BL-3 humans who are ill as a result of exposure to BL-3 agents are cared for in an ordinary hospital room with barrier nursing procedures. 

Isolation of ventilation ducts leading out of the treatment room to prevent spreading of the contamination throughout the hospital. 

The background area is the room in which the LAF or safety cabinet, or isolator is housed. In the case of open-fronted cabinets there is a distinction in background requirements between the different guidelines mentioned before. The PIC/S guide [2] and the German ADKA guideline [9] require at least EU Grade C, the Dutch hospital... 

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