Positive pressure room: Air will flow out of the room instead of in, so that any airborne microorganisms (e.g., bacteria) that may infect the patient are kept away.
Negative pressure room: a ventilation system that generates negative pressure to allow air to flow into the isolation room but not escape from the room, as air will naturally flow from areas with higher pressure to areas with lower pressure, thereby preventing contaminated air from escaping the room.
You have identified a burn patient (60% burns) in the ICU with serial blood and tissue cultures positive for Aspergillus fumigatus. Upon reviewing the patient in ICU and inspecting the area, you notice a bulging ceiling tile in the corridor adjacent to his room. You are told that the tile has been like this for one week now. Maintenance is called and the ceiling tile is removed, at which point you notice greenish discoloration of the inner surface of the tile and evidence of water leakage from the pipe above. The air intake into the patient’s room runs above the discoloured ceiling tile.
Case Six Questions:
1. What special precautions should have been taken for this burn patient upon his admission to the unit?
Burns ensured that this patient was at significant risk for infection upon admission. Noting the leaking pipe and water damaged tile above this patient’s room air intake are the probably cause of this patient’s Aspergillus fumigatus positive serial blood and tissue cultures. Considering that this ceiling tile had been noticilibly water damaged for an entire week staff missed an opportunity and failed in their responsability to protect their patient from harm.
“The primary goal of the infection prevention team during maintenance, renovation or construction in healthcare facilities is to protect susceptible patients, visitors, and healthcare workers from acquiring infections” (Lautenback, p. 440)
Upon this patient’s admission to the unit an infection control risk assessment should have been performed. This would have provided the opportunity to identify factors, such as the enviromental source of infection. The moldy ceiling tile and leaking pipe could have been fixed prior to admission into all ICU rooms close to this potential source of infectious reservoir.
Special precautions (from Lautenback, p.445) that should have taken place to protect this burn patient are:
- this patient should not have been admitted into a room close to this area of water damage ceiling tile.
- the area above the bulging ceiling tile should have been assessed to ensure it did not affect essiental services above it, such as the leaking water pipe and most importantly the air intake to the patient’s room.
- A plan should have been developed as soon as abnormality in the cieling tile was noted a week ago so that infection risks were minimized for the patient as well as others in that area
- It should have been determined if the patient needed to be relocated to another room or even another unit to protect the patient from infection risk due to the Aspergillus growing in the ceiling at that room’s air intake.
- The infection control risk assessment that should have taken place on admission of this patient to the unit should have determined what barriers were necessary to reducing the risk to this patient such as shutting off the contaminated air intake vent that fed that patient’s room or perhaps sealed off that part end of the corridor and rooms fed by that air intake vent until maintenance had completed repairs and the reservoir of infection no longer existed.
- Prior to this patient’s admission it should have been discussed if the air intake vent above the bulging cieling tile needed to be sealed off to prevent Aspergillus from reaching the patient’s room
Note that another track to take for this answer might be this:
The patient should have had a primary wound assessment.
Due to total body surface area burned being 60%. The patient is a very high risk of infection. The burns result in the patient being immunocompromised and at high risk of opportunistic infections like Aspergillus.
Measures if infection prophylaxis should have been undertaken – whole body cleaning, shaving, microbial surveillance placement of wet and aseptic wounds covers for 24hrs. Subsequent wound evaluations. Use of modern facility “burn box” that allows for regulation of temperature and humidity in the room allowing temperatures to be regulated from 21-38 degrees Celsius and humidity regulated up to 60%.(Ann, p.3)
Use of the burn box also allows for increased pressure between the box and rest of the unit Allowing for air exchanges at least 10 fold per volume of the burn box per hour. (Ann, p.3)
these burn boxes have microbial filters implanted in their air exchanges – this would help prevent infection in our patient had this been in place!
Regular microbial surveillance of the environment should have been in place such as the filter membranes of the air conditioner, and water connections. Given our patient was infected via spores in the air vent having these might have prevented infection. (Ann, p.4)
2. If you had been asked to perform an infection control risk assessment prior to tile removal and plumbing remediation, what risk would you assign and why?
I would assign it a Group 4, highest risk, due to the population or geographic risk group bring in the ICU (PHAC, 2001) and classed in the highest risk group given this patient has burns and Lautenback, p. 447, classifies burn unit care patients under the highest risk group.
I would also assign it a Type C for type of construction activity because the assessment will show that the tile needs removing, that water leakage is present requiring the water pipe above to be distrupted and that air vent distruption will also have to take place during repair (PHAC, 2001).
3. What precautions should the maintenance workers take when they remove and dispose of the affected materials? Is this considered biohazardous material?
For dust control the maintenance workers should:
- erect an impermiable barrier from ceiling to floor, including area above the ceiling made of 2 layers of polyethylene or sheetrock
- “Ensure that windows, doors, plumbing penetrations, electrical outlets and intake and exhaust vents are properly sealed with plastic and duct taped within the construction/renovation area
- Vacuum air ducts and spaces above ceilings if necessary
- Ensure that construction workers wear protective clothing that is removed each time they leave the construction site before going into patient care areas
- Do not remove dust barrier until the project is complete and the area has been cleaned thoroughly and inspected
- Remove dust barrier carefully to minimize spreading dust and other debris particles associated with the construction project
- Before starting the construction project erect an impermeable dust barrier that also has an anteroom
- Place a walk-off mat outside the anteroom in patient care areas and inside the anteroom to trap dust from the workers’ shoes, equipment and debris that leaves the construction zone
- Ensure that construction workers leave the construction zone through the anteroom so they can be vacuumed with a HEPA filtered vacuum cleaner before leaving the work site; or that they wear cloth or paper coveralls that are removed each time they leave the work site
- Direct all personnel entering the construction zone to wear shoe covers
Ensure that construction workers change the shoe covers each time they leave the work site
- Repair holes in walls within 8 hours or seal them temporarily” (PHAC, 2001)
When working on the air intake ventiliation the maintenance workers should:
- “Maintain negative pressure within construction zone by using portable HEPA equipped air filtration units
- Ensure air is exhausted directly outside and away from intake vents or filtered through a HEPA filter before being recirculated
- Ensure ventilation system is functioning properly and is cleaned if contaminated by soil or dust after construction or renovation project is complete
- Ensure negative pressure is maintained within the anteroom and construction zone
- Ensure ventilation systems are working properly in adjacent areas
- Review ventilation system requirements in the construction area with ICP to ensure system is appropriate and is functioning properly” (PHAC, 2001)
With regards to debris removal, disposal and cleanup the workers should:
- “Remove debris at the end of the work day
- Erect an external chute if the construction is not taking place on ground level
- Vacuum work area with HEPA filtered vacuums daily or more frequently if needed” (PHAC, 2001)
With regards to working on the leaking water pipe the workers should:
“Flush water lines at construction or renovation site and adjacent patient care areas before patients are readmitted”(PHAC, 2001)
Are the affected material biohazardous?
A biohazard is “a biological agent or condition that is a hazard to humans or the environment; also : a hazard posed by such an agent or condition” (Merriam-Webster). The Public health agency of Canada recommends for disposal of material that have come in contact or been contaminated with Aspergillus species through decontamination by “autoclave, chemical disinfection, gamma irradiation or incineration before disposing” (PHAC, 2010)
4. How should air flow be designed in intensive care areas such as burn units and ICUs?
The air flow system should be designed with a humidity regulator in place and have frequent air exchanges . “If the humidity level is high and the number of air exchanges inadequate, walls, ceilings, and vents may drip water onto sterile supplies or clean surfaces” (Lautenbach, p.451). As we know from this case, damp areas of wall or ceiling can be a breeding ground for molds and fungi that can cause infections.
Infection prevention personel should be involved in the planning phase of all areas, especially those caring for immunocompromised patients such as those in the burn unit and ICU. They must ensure that “air handling systems will be adequate to provide the ventiliation required for the area” (Lautenback, p. 451).
The air flow systems should be designed to provide to patient rooms “6 air exchanges per hour (ACH), of which 2 ACH must be of outside air” (Lautenbach, p.451)
Exterior air intakes should be 8m upwind of exhaust outlets and the bottom of an air intake should be at least 2m above the ground, or 1m above roof level. “Intakes should also be located away from cooling towers, trash compactors, loading docks, heliports, exhausts from biologial safety hoods, ethylene oxide sterilizers, aerators, and inceinerators” (Lautenbach, 451).
5. Guidelines exist for new construction and renovations in hospitals. Give examples of these and explain how they differ from construction regulations.
With increasing use of electronics and increasing use of computers for electronic health records and order entry ensure that washable covers for keyboards are being used. (Rodak, 2011).
1. Lautenbach, E., Woeltje, K., and Malani, P. (2010) Practical HealthcareEpidemiology, 3rd ed.
2. Public Health Agency of Canada, PHAC. (2001). Construction-related Nosocomial Infections in Patients in Health Care Facilities: Decreasing the Risk of Aspergillus, Legionella and Other Infections. Accessed March 21, 2017 from http://www.collectionscanada.gc.ca/webarchives/20071212095242/http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/01vol27/27s2/27s2f_e.html#risk
3. Merriam-Webster. 2017. Accessed Mar 21, 2017 from https://www.merriam-webster.com/dictionary/biohazard
4. Public Health Agency of Canada. (2010). Aspergillus spp. pathogen safety data sheet – infectious substances. Accessed Mar21, 2017 from http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/aspergillus-spp-eng.php
5. Roadkill, Sabrina. (2011). 5 ‘Cs’ for Addressing Infection Control in Design & Construction. Accessed March 22, 2017 from http://www.beckersasc.com/asc-quality-infection-control/5-cs-for-addressing-infection-control-in-design-a-construction.html?Construction
6. Ann burns fire disasters. 2013. Fungal infections in burns:a comprehensive review. Accessed March 24, 2017 from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3917146/
“Pink noise has more lower octaves than typical white noise and is hardly soothing. For example, it can be one-second pulses of the sound of a rushing waterfall. The short pieces of quick, quiet sounds would be really annoying if you were trying to fall asleep.
But the pink noise isn’t trying to get you to fall asleep; it’s trying to keep you in a very deep sleep where you have slow brainwaves. This is one of our deepest forms of sleep and, in particular, seems to decline in aging adults.”
“Two factors with the most impact are fatigue and stress. There is strong scientific evidence linking fatigue and performance decrement making it a known risk factor in patient safety . Prolonged work has been shown to produce the same deterioration in performance as a person with a blood alcohol level of 0.05 mmol/l, which would make it illegal to drive a car in many countries ”