Archive | May 11, 2017

Case 6: Infection control in institutional contruction and design (practice/redo)

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?

The patient has burns to 60% of his body and is therefore at very high risk of infections.

Precautions for the patient upon admission to the unit:

  • physical isolation in a private room
  • gloves and gowns during patient contact
  • full body wound assessment
  • appropriate empirical antimicrobial therapy
  • laboratory surveillance cultures
  • routine microbial burn wound cultures (Coban, 2012)
  • patient should have been moved or air intake sealed off when discoloured ceiling tile noted near the air intake to his room

“During, maintenance, renovation and contruction, bacterial or fungal microorganisms in the dust and dirt can contaminate air handling or water systems wich can transmit these organisms to susceptible persons” (Lautenbach, p. 394).
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?

Type construction activity: Type C (working on ducts, removing ceiling tiles) (LAUTENBACH, P. 446).

Patient risk group: high risk, immunocompromized, burn patient (Lautenbach, p. 447).

Class of precautions: III/IV due to highest risk and type C (Lautnbach, p. 447).
3. What precautions should the maintenance workers take when they remove and dispose of the affected materials? Is this considered biohazardous material?

Precautions to be taken:

Seeing as we designated the risk class III/IV above, class 4 precations should be used for the most encomapssing precations for all involved.

Class IV precautions to be taken during the contruction project according to Lautenback, p. 448 are as follows:

  • Isolate HVAC systems in the work area to prevent air duct contamination
  • Implement barrier cube method or barrier sealing off of work area out of sheetrock, plywood, or plastic (Lautenback, p. 448)
  • maintain negative air pressure within work site
  • use HEPA equipped air filitration units (lautenback, p. 448)
  • seal off holes, pipes, conduits, punctures
  • construct anteroom: 1. all personel to be HEPA vaccummed before leaving the work site or 2. workers change out of paper coveralls each time they exit the work site (Lautenback, p. 448)
  • all personel to wear shoe covers  that are changed prior to exiting the work site
  • contain contruction waste: transport in tightly covered containers with added cover over transport receptacle or cart (Lautenbach, p. 448).

Disposal of material: Aspergillus is not a biohazard because it is readily found in the hospital environment (dust, dirt, construction debris). Aspergillus is not harmful to healthy people therefore can be disposed of without biohazard precautions(Lautenbach, 441).

4. How should air flow be designed in intensive care areas such as burn units and ICUs?

  • patient rooms should have 6 air changes per hour (Lautenbach, p. 451).
  • 2/6 of the air exchanges per hour must be outdoor exchanges
  • rooms where high risk procedures are performed such as bronchoscopies, should have negative pressure with respect to adjacent areas (Lautenbach, p.451)
  • these high risk ventiliation procedure rooms should have flexible ventilation where pressure can be changed from neutral to negative (Lautenbach, p. 451).
  • If a room with special ventiliation is renovated, air exchanges and air pressure should be measured following the renovation
  • exterior air intakes should be place minimum 8m upwind of exhaust outlets
  • the bottom of such air intakes should be minimum 2m above ground or 1m above roof level
  • air intakes should be located away from cooling towers, trash compactors, loading docks, heliports, biological safety exhaust hoods, sterilizers, aerators, and incinerators (Lautenbach, p. 451).

5. Guidelines exist for new construction and renovations in hospitals. Give examples of these and explain how they differ from construction regulations.

References:

1. Coban, Y. K. (2012). Infection control in severely burned patients. World Journal of Critical Care Medicine, 1(4), 94–101. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3953869/

2. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.