HEALTH CARE: Unsafe Harbours

During the second week of June this year, three deaths in one of Canada’s leading heart surgery centres became shocking news. Radio-Canada announced that post-operative problems leading to nosocomial infections (infections caused by hospital environments) had resulted in the death of three patients at the Institut de Cardiologie de Montral/Montreal Heart Institute. The Institute is known to be a pioneer in heart transplants. Only a year after Dr. Christian Barnard performed the world’s first heart transplant in South Africa, Dr. Grondin of the Montreal Heart Institute performed the first heart transplant in the history of the province of Quebec.

Needless to say, these three deaths were very disturbing to everyone, particularly those in the healthcare industry. There was especial concern because they came not too long after another dramatic announcement that anti-microbial resistant pathogens cannot be destroyed using traditional disinfectant solutions. Staphylococcus Aureus is the most frequently isolated pathogen that cannot easily be destroyed.

Early this year, another hospital was in the headlines. The Pavillon Honor-Mercier of the Rseau Sant Richelieu-Yamaska was under investigation because the entire building was diagnosed with a mildew problem caused by the accumulation of moisture in the insulation of the exterior walls. The cost of the rehabilitation is estimated to be well over $40 million.

A year and a half ago, the death of three or four patients suspected to have been caused by nosocomial infection during surgical operations at the Royal Victoria Hospital went under investigation. A newspaper article in La Presse said that a mushroom, the size of a golf ball, was found in the chest of a deceased patient. Doesn’t that scare you? That was probably the intent of the journalist who wrote the article.

Laurier Nichols, P.E. met the engineer in charge of the building services in the hospital and her description of the situation was quite different. It was suspected that a patient might have been infected by Aspergillus (a mushroom found in mildew). The problem was under investigation by the Center for Disease Control (CDC) in the United States. Unfortunately, it is very difficult to positively identify the cause of a problem in the medical field. Nevertheless, the operating rooms of Montreal’s Royal Victoria Hospital were closed for four months and approximately a million dollars was spent to replace the ventilation system and upgrade other mechanical services.

Preventive steps

Mr. Nichols was invited by the Corporation d’hbergement du Qubec to join the National Committee on Indoor Air Quality in Health Care Centres. The committee was formed to develop guidelines for the prevention of nosocomial infection during the construction, renovation and maintenance of heath care facilities.

At the beginning of the discussions, many of the participants questioned the severe budget cuts building services face in the hospital sector. Those involved in the design, construction or operation of buildings are seriously concerned with the possible link between the maintenance cuts and the increase of identified nosocomial infection.

A doctor specializing in microbiology who was also a member of this committee had a different view. He said that the infection caused by Aspergillus is a rare case and that most of the time the problem originates from bacterial infection caused either by the patient himself, the instruments used during the operation or even the surgeon’s hands. He also pointed out that the Center for Diseases Control has no recommendation for the systematic measurement of the air quality in operating rooms. This is because there is no significant evidence of potential problems.

New guidelines

How is the design of heating, ventilating and air-conditioning (HVAC) systems in new health care facilities regulated? One of the best new guides is by the American Institute of Architects (AIA). A year ago it issued a revised standard entitled “Guidelines for the Design and Construction of Hospital and Health Care Facilities.” The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) collaborated with the architectural institute in producing the guideline.

Several changes were made to the previous version. The most important recommendations are:

Surgery and critical care. The identification of certain rooms was revised to take into account the new types of intervention. Since the waiting areas may be occupied by persons with undiagnosed communicable respiratory diseases, the ventilation rate was increased from six air changes per hour (ACH) to 12 ACH. Trauma, triage and procedure rooms are other areas where a higher airflow rate is required. It is also recommended to use High Efficiency Particulate Air (HEPA) filtration if recirculation is used in these areas.

Nursing. The major change is an increased ventilation rate in the patient room. The recommended ventilation is now six ACH while the previous ventilation rate was two ACH. As most hospital areas are used for nursing services (mostly patients’ rooms) this change has a major impact on the design of HVAC systems for future hospitals. Other areas such as protective environment rooms and airborne infection isolation rooms require 12 ACH.

Ancillary. Most of these services require six ACH. A higher ventilation rate is required in specialized areas: X-ray (15 ACH), darkroom (10 ACH), sterilizing (10 ACH), and autopsy room (12 ACH).

There are several publications available from the U.S. Department of Health for the prevention of infections. Unfortunately, these documents are prepared mostly for medical experts and provide few recommendations for HVAC designers. They contain information such as how to clean a patient, and requirements on clothing and hand washing.

Quebec’s National Committee on Indoor Air Quality in Health Care Centres mentioned earlier has produced a technical guide that defines several measures to follow during construction or renovation activities in a hospital.1 The guide splits the site areas into four major groups of sensitivity. The construction interventions are also split into four groups, starting with small interventions (opening of a ceiling tile for inspection or adjustment) and ending with full renovation and construction.

The several measures for very sensitive areas require the installation of a temporary wall barrier and keeping a negative air pressure in the work area in order to eliminate any possible transfer between the construction site and the sterile areas. Some of the requirements are similar to the regulations for construction projects that involve asbestos removal. The Quebec technical guide is very similar to a guide issued in July last year by Health Canada.2

The effect of budget cuts

What should the consulting engineer’s position be when dealing with problems in health care facilities? On one hand we have regulations that are more stringent, and on the other hand we have the opinion of some specialists who believe that the indoor air quality (microbiology) is only a concern for causing infection in rare cases. The medical personnel have a greater influence than the building maintenance personnel over the administrators in most hospital and health care centres. Consequently, it is not surprising to see that budget cuts mainly affect the maintenance budgets.

But a Draft Guideline for Environmental Infection Control in Healthcare Facilities published in 2001 by the U.S. Center for Disease Control and Prevention suggests that we should not shortcut building systems. This document puts an emphasis on filtration, air changes per hour (AHU) and HVAC maintenance. “HEPA filters are at least 99.97% efficient for removing particles >0.3 m in diameter.” (As a reference, Aspergillus spores are 2.5-3.0 m in diameter).

The requirements of the guidelines are based on logic and facts. Why wouldn’t the air quality create an infection problem in a hospital when it is a major concern in the pharmaceutical or the micro-electronics industry? In our view, health care experts a
nd the public they serve should be more concerned about budget cuts in the operation and maintenance of mechanical and electrical services in hospital and health care facilities. Proper budgets must be allocated for the construction of good quality buildings.

Laurier Nichols, P.E. is a senior engineer with Dessau-Soprin of Montreal. Marie-Judith Jean-Louis, EIT, is also with the firm.

2 Construction related Nosocomial Infections in Patients in Health Care Facilities: Decreasing the Risk of Aspergillus, Legionella and Other Infections.