Hospital Design and Risk of Nosocomial Infections: A Prospective Controlled Trial

• Sponsor: University of Calgary (Other)
• Overall Status: Completed
• CT.gov ID: NCT00563186
• Collaborator: Calgary Health Region (Other), Canadian Institutes of Health Research (CIHR) (Other), Alberta Heritage Foundation for Medical Research (Other)
• Enrollment: 1,514
• Location: 1
• Arms: 2
• Duration (Months): 32.1
• Patients Per Site Per Month: 47.2

Study Details

Study Description

Brief Summary

With the construction of a new medical teaching ward with features designed to reduce hospital-acquired infections, we hypothesized that the design of the new ward was the major factor that contributed to the improved outcomes and designed a prospective, controlled study to examine this hypothesis.

Condition or Disease	Intervention/Treatment	Phase
Vancomycin Resistant Enterococci Infection; Clostridium Difficile Infection; Nosocomial Infection; Methicillin Resistant Staphylococcus Aureus Infection (MRSA)	Other: Admission to a novel hospital ward	N/A

Detailed Description

Recent studies have underscored the importance of optimizing design standards to maximize patient and health care worker safety, including the prevention of hospital acquired infections (HAI) in patients. Health care associated infections are a major contributor to adverse events in healthcare, estimated to occur in 3-20% of all acute care admissions in Canada. A review of the role of the physical environment and adverse events identified no prospective randomized controlled trials of physical plant design and its impact on hospital acquired infections. With the construction in 2004 of a unique $5-million, 36-bed medical teaching unit at Foothills Medical Centre (FMC) with a prototypical design with features to reduce HAI and an overarching mandate to test new concepts in health care delivery, the opportunity exists to rigorously study the impact of design, construction and engineering controls (DCECs) on specific hospital acquired infections and antibiotic resistant organism (ARO) colonization. In the first year of operation the incidence density of hospital acquired infections and/or colonization with marker organisms has declined by almost 70%. Given that there were no changes in the types of patients, medical, nursing or housekeeping staff, we hypothesized that the design of the new ward was the major factor which contributed to the improved outcomes. Given the pre-post study design we are uncertain as to which factor is most important in reducing HAI /colonization rates.

We therefore propose to conduct a prospective, controlled investigator blinded trial of the impact of DCECs on specific HAIs and ARO colonization. We propose to allocate general medical patients, with an allocation scheme that incorporates randomness, to one of 2 types of medical wards at the FMC, either "historic design" wards (ie control wards in the non-renovated portions of FMC or Unit 36 (the experimental new design ward). The medical wards are very similar with respect to the patient mix, acuity of care, medical staff, nursing staff and skill mix, educational levels, housekeeping and levels of knowledge about infection control practices but differ in design. Variables which may otherwise have confounded the outcome of hospital acquired infections/colonizations may be controlled allowing the effect of the differences in design, construction and engineering controls to be studied. The older design wards have predominantly 4-bed and some 2-bed rooms with shared bathrooms, less space and fewer handwashing sinks/patient. The study will require 9750 patient days of observation in the "historic design"wards and 19,500 patient days of observation in Unit 36 to ensure 80% statistical power to detect a 60% difference in the rates of incident cases of selected HAIs and ARO colonizations (the primary outcome measure) with an α level of 0.05 assuming that incident cases in each unit follow Poisson distribution based on well established historic trends on these units.

In addition we propose to add a nested mixed methods social science study within the construct of the prospective study to understand the fit between the health care workers and the physical environment. In recognition that the proposed intervention may be defined as a "complex intervention" with HAIs affected by many factors related to physical plant design, organizational factors, and health care worker practices, it was considered prudent to measure and describe worker and organizational factors on the medical inpatient care units included in the proposed intervention.

Our proposed study is being done with the collaboration and support of both the Operations and Planning & Capital Development portfolios of the Calgary Health Region. The Region is in the throes of a major expansion with over $1 billion of new capital health care developments and the addition of over 700 new beds by 2010. The finding of favorable outcomes on the medical ward with its special design, construction and engineered controls in a well designed prospective study of this nature would be the first of its kind and has the potential to change the fundamental design of new medical wards in the Calgary Health Region and in other jurisdictions within Canada.

Study Design

• Study Type: Interventional
• Actual Enrollment: 1514 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Single (Investigator)
• Primary Purpose: Prevention
• Official Title: Physical Plant Design and Engineering Controls and the Prevention of Nosocomial Infections and Antibiotic Resistant Organism Colonization Events - A Proposal for a Prospective Controlled Trial
• Study Start Date: Jun 1, 2007
• Actual Primary Completion Date: Feb 1, 2010
• Actual Study Completion Date: Feb 1, 2010

Arms and Interventions

Arm	Intervention/Treatment
Experimental: A Admission to a novel hospital ward (e.g. abundance of sinks, predominance (80%) of private rooms, absence of shared bathrooms, absence of curtains)	Other: Admission to a novel hospital ward; Hospital admission to a ward with novel infection control design features (e.g., abundance of sinks, predominance (80%) of private rooms, absence of shared bathrooms, absence of curtains)
No Intervention: B Hospital admission to a ward with traditional design features (eg. lack of sinks, predominance of 4-bed rooms [80%], shared bathrooms, curtains present)

Outcome Measures

Primary Outcome Measures

1. Incidence Density of Hospital-acquired Infection With Clostridium Difficile (CDI), and Hospital-acquired Infection or Colonization With Vancomycin-resistant Enterococcus (VRE), or Methicillin-resistant Staphylococcus Aureus (MRSA). [participants were followed for the duration of hospital stay, an average of 10 days]

Secondary Outcome Measures

1. Number of MRSA, VRE and CDI Occurring in Single-bed Rooms vs. Multiple Bed Rooms AND Occurring in Outbreaks Related to the Primary Case [in-hospital]

   If a patient is swabbed and found to be positive (for MRSA or VRE), their current roommate\roommates will be swabbed (if in the same room > 48 hrs) as well as any other patient that shared a room with this patient for > 48 hours during this stay. Any patient who may have shared a bathroom with the first patient would also be swabbed. If the results from this investigation showed any positive roommates, then the process would repeat for each positive patient. Then, in consult with the infectious disease physician, a call will be made regarding a point prevalence study to determine the attack rate\burden of disease on the unit.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years and Older
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• are adults aged 18 or older with medical diagnoses being admitted to one of three in-hospital general medical services at the FMC (one of the two in-patient General Internal Medicine services at the FMC)

• are admitted via the emergency room

• are admitted from the urgent assessment clinic or the community

Exclusion Criteria:

• are admitted from another acute care medical institution

• require telemetry monitoring of their cardiac rhythm (a specific medical situation that dictates need for admission to a nonUnit 36 bed).

• have other clinical circumstances (eg clinical instability) mandating a physician to indicate clinical preference for admission of the patient to a specific location in the hospital

• are admitted from the intensive care unit or another hospital ward

• are admitted for less than 48 hours

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Foothills Hospital	Calgary	Alberta	Canada	T2N 2T9

Sponsors and Collaborators

• University of Calgary
• Calgary Health Region
• Canadian Institutes of Health Research (CIHR)
• Alberta Heritage Foundation for Medical Research

Investigators

• Principal Investigator: John M Conly, MD, University of Calgary
• Principal Investigator: William A Ghali, MD, University of Calgary
• Principal Investigator: Manuel Mah, MD, Calgary Health Region
• Principal Investigator: Donna Holton, MD, Calgary Health Region
• Principal Investigator: Elizabeth A Henderson, PhD, University of Calgary
• Principal Investigator: Peter Faris, PhD, University of Calgary
• Principal Investigator: Jean Wallace, PhD, University of Calgary

Study Documents (Full-Text)

None provided.

More Information

Additional Information:

• Website for the Medical Ward of the 21st Century Initiative.

Publications

None provided.

• Responsible Party: Dr. John Conly, Dr John Conly, University of Calgary
• ClinicalTrials.gov Identifier: NCT00563186
• Other Study ID Numbers: CIHR-PHE-81963
• First Posted: Nov 26, 2007
• Last Update Posted: Oct 23, 2018
• Last Verified: Oct 1, 2018

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No
• Keywords provided by Dr. John Conly, Dr John Conly, University of Calgary: infection control; nosocomial infection; hospital design; physical plant design; antibiotic resistant organisms; MRSA; VRE; CDI
• Additional relevant MeSH terms: Infections; Communicable Diseases; Clostridium Infections; Staphylococcal Infections; Cross Infection

Study Results

Participant Flow

Recruitment Details	Between June 2007 and February 2010 all patients admitted to the General Internal Medicine Service at Foothills Medical Centre from the emergency room, urgent assessment clinic or the community were assessed for eligibility into the study.
Pre-assignment Detail	Exclusions: admitted from another health care facility or another hospital ward or to a non-study unit, required telemetry, < 18 years of age, or were preferentially admitted to the novel or the traditional design ward. Once pre-assigned, excluded if LOS <48 hours (Novel ward=97, Historic ward=74); or data incomplete (Novel ward=1; Historic ward=1)

Arm/Group Title	Novel Hospital Ward Admission	Traditional Hospital Ward Admission
Arm/Group Description	Hospital admission to a ward with novel infection control design features (e.g. abundance of sinks, predominance (80%) of private rooms, absence of shared bathrooms)	Hospital admission to a ward with traditional infection control design features (e.g. lack of sinks, predominance (80%) of 4-bed rooms, shared bathrooms)
Period Title: Overall Study
STARTED	1008	679
COMPLETED	910	604
NOT COMPLETED	98	75

Baseline Characteristics

Arm/Group Title	Novel Hospital Ward Admission	Traditional Hospital Ward Admission	Total
Arm/Group Description	Hospital admission to a ward with novel infection control design features (e.g. abundance of sinks, predominance (80%) of private rooms, absence of shared bathrooms)	Hospital admission to a ward with traditional infection control design features (e.g. lack of sinks, predominance (80%) of 4-bed rooms, shared bathrooms)	Total of all reporting groups
Overall Participants	910	604	1514
Age (Count of Participants)
<=18 years	0 0%	0 0%	0 0%
Between 18 and 65 years	400 44%	305 50.5%	705 46.6%
>=65 years	510 56%	299 49.5%	809 53.4%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	60.62 (18.44)	63.22 (18.78)	61.66 (18.61)
Sex: Female, Male (Count of Participants)
Female	407 44.7%	278 46%	685 45.2%
Male	503 55.3%	326 54%	829 54.8%
Region of Enrollment (participants) [Number]
Canada	910 100%	604 100%	1514 100%

Outcome Measures

1. Primary Outcome

Title	Incidence Density of Hospital-acquired Infection With Clostridium Difficile (CDI), and Hospital-acquired Infection or Colonization With Vancomycin-resistant Enterococcus (VRE), or Methicillin-resistant Staphylococcus Aureus (MRSA).
Time Frame	participants were followed for the duration of hospital stay, an average of 10 days

Outcome Measure Data

Analysis Population Description

All patients meeting inclusion criteria, and admitted to the General Internal Medicine (GIM) service on the novel infection control design ward or the traditional infection control design ward were followed for the development of MRSA or VRE infection (inf) or colonization (col) or CDI after 48 hours of admission

Arm/Group Title	Novel Hospital Ward Admission	Traditional Hospital Ward Admission
Arm/Group Description	Hospital admission to a ward with novel infection control design features (e.g. abundance of sinks, predominance (80%) of private rooms, absence of shared bathrooms)	Hospital admission to a ward with traditional infection control design features (e.g. lack of sinks, predominance (80%) of 4-bed rooms, shared bathrooms)
Measure Participants	910	604
CDI	1.16	0.84
MRSA Infections / Colonizations	1.27	1.01
VRE Infections / Colonizations	0.53	0
Overall Total Infections / Colonizations	2.96	1.85

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Novel Hospital Ward Admission, Traditional Hospital Ward Admission
	Comments	It was calculated that this study will require 9750 patient days of observation in the "traditional design" wards and 19,500 patient days of observation in the "novel design" ward to ensure 80% statistical power to detect a 60% difference in the rates of incident cases of selected HAIs and ARO colonizations (the primary outcome measure) with an α level of 0.05 assuming that incident cases in each unit follow Poisson distribution based on well established historic trends on these units
	Type of Statistical Test	Superiority or Other
	Comments	This statistical analysis applies to the overall VRE, CDI and MRSA infection and colonization events expressed as incidence density (per 1000 patient-days at risk).
Statistical Test of Hypothesis	p-Value	0.18
	Comments
	Method	Poisson
	Comments
Method of Estimation	Estimation Parameter	Incidence Rate ratio
	Estimated Value	1.60
	Confidence Interval	(2-Sided) 95%; 0.80 to 3.22
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.57
	Estimation Comments	Numerator is novel ward and denominator is traditional ward.

2. Secondary Outcome

Title	Number of MRSA, VRE and CDI Occurring in Single-bed Rooms vs. Multiple Bed Rooms AND Occurring in Outbreaks Related to the Primary Case
Description	If a patient is swabbed and found to be positive (for MRSA or VRE), their current roommate\roommates will be swabbed (if in the same room > 48 hrs) as well as any other patient that shared a room with this patient for > 48 hours during this stay. Any patient who may have shared a bathroom with the first patient would also be swabbed. If the results from this investigation showed any positive roommates, then the process would repeat for each positive patient. Then, in consult with the infectious disease physician, a call will be made regarding a point prevalence study to determine the attack rate\burden of disease on the unit.
Time Frame	in-hospital

Outcome Measure Data

Analysis Population Description

An outbreak occurred when more than 1 case of MRSA, VRE or CDI was epidemiologically linked to a primary case. In total 22 outbreak cases were detected during the study. The location of these outbreak cases (single-bed rooms vs. multi-bed rooms) was identified in the Novel Hospital Ward and the Traditional Hospital Ward

Arm/Group Title	Novel and Traditional Hospital Ward Admission
Arm/Group Description	Number of MRSA, VRE and CDI cases occurring in single-and multiple-bed rooms in Novel Hospital Ward and Traditional Hospital Ward during outbreaks
Measure Participants	1514
Measure Total Number of Outbreak cases	22
Single-bed Rooms	3
Multiple-bed rooms	19

3. Post-Hoc Outcome

Title	Event Incidence Density in Single vs Multi-bed Rooms in Novel Design Ward Only
Description	The incidence density of MRSA, VRE and CDI occurring in single-bed vs. multi-bed rooms was examined on only the novel design ward
Time Frame	In-hospital

Outcome Measure Data

Analysis Population Description

All patients that met the inclusion and exclusion categories and were admitted to the novel design ward were assessed for the development of MRSA, VRE or CDI. The incidence densities in single-bed rooms were then compared to the incidence densities in multiple-bed rooms.

Arm/Group Title	Incidence Density in Single-bed Rooms	Incidence Density in Multi-bed Rooms
Arm/Group Description	# MRSA, VRE and CDI (expressed per 1000 pt days)occurring in single-bed rooms on the novel design ward	# MRSA, VRE and CDI (expressed per 1000 pt days)occurring in multi-bed rooms on the novel design ward
Measure Participants	256	654
Number [events per 1000 patient days]	1.89	3.47

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Novel Hospital Ward Admission, Traditional Hospital Ward Admission
	Comments
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	0.175
	Comments
	Method	Large test for person-time analysis
	Comments
Method of Estimation	Estimation Parameter	Rate Ratio
	Estimated Value	1.929
	Confidence Interval	(2-Sided) 95%; 0.76 to 4.9
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.493
	Estimation Comments

Adverse Events

Arm/Group Title	Novel Hospital Ward Admission		Traditional Hospital Ward Admission
Arm/Group Description	Hospital admission to a ward with novel infection control design features (e.g. abundance of sinks, predominance (80%) of private rooms, absence of shared bathrooms)		Hospital admission to a ward with traditional infection control design features (e.g. lack of sinks, predominance (80%) of 4-bed rooms, shared bathrooms)
All Cause Mortality
	Novel Hospital Ward Admission		Traditional Hospital Ward Admission
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	/ (NaN)		/ (NaN)
Serious Adverse Events
	Novel Hospital Ward Admission		Traditional Hospital Ward Admission
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/910 (0%)		0/604 (0%)
Other (Not Including Serious) Adverse Events
	Novel Hospital Ward Admission		Traditional Hospital Ward Admission
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/910 (0%)		0/604 (0%)

Limitations/Caveats

Chronic overcapacity issues impacted the ability to truly randomize which may have introduced a selection bias,there was an unanticipated conversion of single rooms to multi-bed rooms on the novel ward, limited generalizability outside GIM patients

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.