Standardisation of perioperative urinary catheter use to reduce postsurgical urinary tract infection: an interrupted time series study.

BACKGROUND: Prevention of healthcare-associated urinary tract infection (UTI) has been the focus of a national effort, yet appropriate indications for insertion and removal of urinary catheters (UC) among surgical patients remain poorly defined. METHODS: We developed and implemented a standardised approach to perioperative UC use to reduce postsurgical UTI including standard criteria for catheter insertion, training of staff to insert UC using sterile technique and standardised removal in the operating room and surgical unit using a nurse-initiated medical directive. We performed an interrupted time series analysis up to 2 years following intervention. The primary outcome was the proportion of patients who developed postsurgical UTI within 30 days as measured by the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). Process measures included monthly UC insertions, removals in the operating room and UC days per patient-days on surgical units. RESULTS: At baseline, 22.5% of patients were catheterised for surgery, none were removed in the operating room and catheter-days per patient-days were 17.4% on surgical units. Following implementation of intervention, monthly catheter removal in the operating room immediately increased (range 12.2%-30.0%) while monthly UC insertion decreased more slowly before being sustained below baseline for 12 months (range 8.4%-15.6%). Monthly catheter-days per patient-days decreased to 8.3% immediately following intervention with a sustained shift below the mean in the final 8 months. Postsurgical UTI decreased from 2.5% (95% CI 2.0-3.1%) to 1.4% (95% CI 1.1-1.9; p=0.002) during the intervention period. CONCLUSIONS: Standardised perioperative UC practices resulted in measurable improvement in postsurgical UTI. These appropriateness criteria for perioperative UC use among a broad range of surgical services could inform best practices for hospitals participating in ACS NSQIP.

Elimination of Screening Urine Cultures Prior to Elective Joint Arthroplasty.

Discontinuing routine processing of screening urine cultures prior to elective joint arthroplasty resulted in substantial reduction in urine cultures ordered and antimicrobial prescriptions for asymptomatic bacteriuria, without any significant impact on incidence of prosthetic joint infection. This simple change would be scalable across institutions with potential for significant healthcare savings.

Periprosthetic Infection following Primary Hip and Knee Arthroplasty: The Impact of Limiting the Postoperative Surveillance Period.

BACKGROUND Hip and knee arthroplasty infections are associated with considerable healthcare costs. The merits of reducing the postoperative surveillance period from 1 year to 90 days have been debated. OBJECTIVES To report the first pan-Canadian hip and knee periprosthetic joint infection (PJI) rates and to describe the implications of a shorter (90-day) postoperative surveillance period. METHODS Prospective surveillance for infection following hip and knee arthroplasty was conducted by hospitals participating in the Canadian Nosocomial Infection Surveillance Program (CNISP) using standard surveillance definitions. RESULTS Overall hip and knee PJI rates were 1.64 and 1.52 per 100 procedures, respectively. Deep incisional and organ-space hip and knee PJI rates were 0.96 and 0.71, respectively. In total, 93% of hip PJIs and 92% of knee PJIs were identified within 90 days, with a median time to detection of 21 days. However, 11%-16% of deep incisional and organ-space infections were not detected within 90 days. This rate was reduced to 3%-4% at 180 days post procedure. Anaerobic and polymicrobial infections had the shortest median time from procedure to detection (17 and 18 days, respectively) compared with infections due to other microorganisms, including Staphylococcus aureus. CONCLUSIONS PJI rates were similar to those reported elsewhere, although differences in national surveillance systems limit direct comparisons. Our results suggest that a postoperative surveillance period of 90 days will detect the majority of PJIs; however, up to 16% of deep incisional and organ-space infections may be missed. Extending the surveillance period to 180 days could allow for a better estimate of disease burden. Infect Control Hosp Epidemiol 2017;38:147-153.

Acquisition of methicillin-resistant Staphylococcus aureus (MRSA) in contacts of patients newly identified as colonized or infected with MRSA in the immediate postexposure and postdischarge periods.

The acquisition of methicillin-resistant Staphylococcus aureus (MRSA) after exposure to patients colonized or infected with MRSA was assessed. Among contacts with complete surveillance screening, the rate of acquisition was 5.7% and was lower in those identified postdischarge (17/683, 2.5%) compared with those tested in the immediate postexposure period (62/706, 8.8%).

Do physicians clean their hands? Insights from a covert observational study.

Physicians are notorious for poor hand hygiene (HH) compliance. We wondered if lower performance by physicians compared with other health professionals might reflect differences in the Hawthorne effect. We introduced covert HH observers to see if performance differences between physicians and nurses decreased and to gain further insights into physician HH behaviors. Following training and validation with a hospital HH auditor, 2 students covertly measured HH during clinical rotations. Students rotated off clinical services every week to increase exposure to different providers and minimize risk of exposing the covert observation. We compared covertly measured HH compliance with data from overt observation by hospital auditors during the same time period. Covert observation produced much lower HH compliance than recorded by hospital auditors during the same time period: 50.0% (799/1597) versus 83.7% (2769/3309) (P < 0.0002). The difference in physician compliance between hospital auditors and covert observers was 19.0% (73.2% vs 54.2%); for nurses this difference was much higher at 40.7% (85.8% vs 45.1%) (P < 0.0001). Physician trainees showed markedly better compliance when attending staff cleaned their hands compared with encounters when attending did not (79.5% vs 18.9%; P < 0.0002). Our study suggests that traditional HH audits not only overstate HH performance overall, but can lead to inaccurate inferences about performance by professional groupings due to relative differences in the Hawthorne effect. We suggest that future improvement efforts will rely on more accurate HH monitoring systems and strong attending physician leadership to set an example for trainees. Journal of Hospital Medicine 2015;11:862-864. © 2015 Society of Hospital Medicine.

Indwelling urinary catheter surveillance using a Task-oriented nurse acuity system.

The task-oriented nurse acuity system (TONAS) has long been used to calculate nursing care needs on hospital patient units, and include nursing documentation on indwelling urinary catheter use. We performed a 2500-patient validation study of our organization's TONAS, which demonstrated high interrater reliability with manual audits (κ >0.92). For institutions that continue to rely on manual surveillance of urinary catheter use, a TONAS may represent a reliable method of automated surveillance.

Co-circulation of multiple genotypes of human rhinovirus during a large outbreak of respiratory illness in a veterans' long-term care home.

BACKGROUND: Human rhinoviruses (HRVs) are a well-recognized cause of long-term care home (LTCH) outbreaks of respiratory illness. However, there are limited data on the molecular epidemiology of the HRV types involved. OBJECTIVES: To determine whether a large respiratory outbreak in a LTCH was caused by a single type of HRV, and to describe the clinical impact of the outbreak. STUDY DESIGN: Nasopharyngeal swabs were collected from residents with one or more of the following: fever, cough, rhinitis, or congestion. Specimens were interrogated by multiplex PCR using the ResPlex II assay. Samples positive for HRV were then submitted for genotyping by partial sequence analysis of the 5' untranslated (UTR) and viral protein (VP) 1 capsid regions. RESULTS: Of 71 screened, 56 residents were positive for a HRV during an outbreak that lasted 5.5 weeks; 27 healthcare workers also had respiratory symptoms. Three residents were transferred to hospital and 2 died. Seven units in two wings of the LTCH were affected, resulting in 3152.5 resident unit closure days. Three different HRV genotypes were identified, although HRV-A1 dominated. CONCLUSIONS: This large outbreak of HRVs among residents and healthcare workers in a LTCH was associated with substantial resident and staff morbidity as well as significant unit closures. Multiple types of HRV were implicated but an HRV-A1 type dominated, warranting further investigation into viral determinants for virulence and transmission.

Risk factors for Staphylococcus aureus surgical site infection during an outbreak in patients undergoing cardiovascular surgery.

BACKGROUND: This study examined the epidemiology of an outbreak of Staphylococcus aureus surgical site infections (SSI) after cardiovascular surgery, and analyzed risk factors for S aureus SSIs. METHODS: This was a retrospective case-control study to determine risk factors for S aureus SSI in 38 patients who developed S aureus SSI during the outbreak period, compared with age-, sex-, and procedure-matched controls. S aureus strains were typed by pulsed-field gel electrophoresis. RESULTS: A total of 38 patients had S aureus SSI. Pulsed-field gel electrophoresis identified transmission of 3 S aureus clones (2 MSSA clones and 1 MRSA clone). Twenty-one health care workers were carriers of outbreak strains. In multivariate analysis, the significant risk factors for S aureus SSI were previous cardiac surgery (odds ratio, 7.41; 95% confidence interval, 1.05-52.16) and long procedure duration (odds ratio, 1.49; 95% confidence interval, 1.00-2.21). CONCLUSIONS: This outbreak demonstrates evidence of nosocomial transmission of 3 clones of S aureus in the setting of incomplete compliance with recommended standard perioperative infection control measures, associated with a high prevalence of staff carriage of the predominant outbreak strains.

Are health care workers protected? An observational study of selection and removal of personal protective equipment in Canadian acute care hospitals.

BACKGROUND: The proper use of personal protective equipment (PPE) by health care workers (HCWs) is vital in preventing the spread of infection and has implications for HCW safety. METHODS: An observational study was performed in 11 hospitals participating in the Canadian Nosocomial Infection Surveillance Program between January 7 and March 30, 2011. Using a standardized data collection tool, observers recorded HCWs selecting and removing PPE and performing hand hygiene on entry into the rooms of febrile respiratory illness patients. RESULTS: The majority of HCWs put on gloves (88%, n = 390), gown (83%, n = 368), and mask (88%, n = 386). Only 37% (n = 163) were observed to have put on eye protection. Working in a pediatric unit was significantly associated with not wearing eye protection (7%), gown (70%), gloves (77%), or mask (79%). Half of the observed HCWs (54%, n = 206) removed their PPE in the correct sequence. Twenty-six percent performed hand hygiene after removing their gloves, 46% after removing their gown, and 57% after removing their mask and/or eye protection. CONCLUSION: Overall adherence with appropriate PPE use in health care settings involving febrile respiratory illness patients was modest, particularly on pediatric units. Interventions to improve PPE use should be targeted toward the use of recommended precautions (eg, eye protection), HCWs working in pediatric units, the correct sequence of PPE removal, and performing hand hygiene.

Nosocomial transmission of New Delhi metallo-ß-lactamase-1-producing Klebsiella pneumoniae in Toronto, Canada.

DESIGN: An analysis of a cluster of New Delhi metallo-ß-lactamase-1-producing Klebsiella pneumoniae (NDM1-Kp) and a retrospective case-cohort analysis of risk factors for acquisition in contacts of NDM1-Kp-positive patients. SETTING: A 1,100-bed Canadian academic tertiary care center. PATIENTS: Two index patients positive for NDM1-Kp as well as 45 contacts (roommates, ward mates, or environmental contacts) were investigated. METHODS: Retrospective chart reviews of all patients colonized or infected with NDM1-Kp as well as contacts of these patients were performed in order to describe the epidemiology and impact of infection prevention and control measures. A case-cohort analysis was conducted investigating 45 contacts of NDM1-Kp-positive patients to determine risk factors for acquisition of NDM1-Kp. Rectal swabs were screened for NDM1-Kp using chromogenic agar. Presence of bla(NDM-1) was confirmed by multiplex polymerase chain reaction. Clonality was assessed with pulsed-field gel electrophoresis (PFGE) using restriction enzyme XbaI. RESULTS: Two index cases carrying NDM1-Kp with different PFGE patterns were identified. Nosocomial transmission to 7 patients (4 roommates, 2 ward mates, and 1 environmental contact) was subsequently identified. Risk factors for acquisition of NDM1-Kp were a history of prior receipt of certain antibiotics (fluoroquinolones [odds ratio (OR), 16.8 (95% confidence interval [CI], 1.30-58.8); [Formula: see text]], trimethoprim-sulfamethoxazole [OR, 11.3 (95% CI, 1.84-70.0); [Formula: see text]], and carbapenems [OR, 16.8 (95% CI, 1.79-157.3); [Formula: see text]]) and duration of exposure to NDM1-Kp-positive roommates (26.5 vs 6.7 days; [Formula: see text]). CONCLUSION: Two distinct clones of NDM1-Kp were transmitted to 7 inpatient contacts over several months. Implementation of contact precautions, screening of contacts for NDM1-Kp carriage, and attention to environmental disinfection contributed to the interruption of subsequent spread of the organism. The appropriate duration and frequency of screening contacts of NDM1-Kp-positive patients require further study.

Impact of the 2009 influenza A (H1N1) pandemic on Canadian health care workers: a survey on vaccination, illness, absenteeism, and personal protective equipment.

BACKGROUND: Data are limited on the impact of the 2009 H1N1 influenza A pandemic on health care worker (HCW) vaccination, illness, absenteeism, and personal protective equipment (PPE) use. METHODS: A survey was completed by HCWs from 14 hospitals participating in the Canadian Nosocomial Infection Surveillance Program who provided direct care to patients with pH1N1 influenza in high-risk units between September and December 2009. RESULTS: Surveys were returned from 986 HCWs (80% nurses, 14% respiratory therapists, and 6% physicians). HCWs working in an intensive care unit (78%) or a designated influenza ward (67%) were more compliant with wearing an N95 respirator for aerosol-generating medical procedures than those working in an emergency department (47%; P < .001). HCWs who worked in health care for >11 years were more compliant with wearing protective eyewear than those who worked for ≤11 years (69% vs 54%; P < .001). A total of 815 HCWs (83%) reported having received the pH1N1 influenza vaccine, and 372 (38%) reported having received the 2009-2010 seasonal influenza vaccine. Influenza-like illness was reported by 236 (24%) HCWs, 170 of whom (72%) reported missing work. CONCLUSIONS: Experience working in health care improves PPE use and HCWs in emergency departments should be targeted for interventions to improve PPE compliance. pH1N1 influenza vaccine coverage was high, but seasonal influenza vaccine coverage was low, and significant HCW illness and absenteeism were reported.

A Caenorhabditis elegans host model correlates with invasive disease caused by Staphylococcus aureus recovered during an outbreak in neonatal intensive care.

BACKGROUND: Caenorhabditis elegans has previously been used as a host model to determine the virulence of clinical methicillin-resistant Staphylococcus aureus isolates. In the present study, methicillin-susceptible S aureus (MSSA) strains associated with an outbreak in a neonatal intensive care unit (NICU) were investigated using the C elegans model. METHODS: Two distinct outbreak clones, MSSA type-C and MSSA type-G, were identified by pulsed-field gel electrophoresis in a MSSA outbreak during a seven-month period in the NICU of the Sunnybrook Health Sciences Centre (Toronto, Ontario). MSSA type-C was associated with severe infection, while type-G was associated with less invasive disease. Four representative type-C isolates, three type-G and three infant-colonized isolates unrelated to the outbreak, were sent to Calgary (Alberta), for the double-blinded virulence tests in the C elegans host model and for further molecular characterization. RESULTS: The invasive outbreak strains (type-C) demonstrated highly nematocidal activity, the noninvasive outbreak strains (type-G) an intermediate virulence, and the outbreak-unrelated colonization isolates demonstrated avirulence or low virulence in the C elegans model, with mean killing rates of 93.0%, 61.0% and 14.4% by day 9, respectively, for these three group strains. Different group MSSA strains had their own unique genetic profiles and virulence gene profiles, but all isolates within the same group (type-C or type-G) shared identical genetic characteristics and virulence gene patterns. CONCLUSIONS: The present blinded evaluation demonstrated that the nematocidal activities of MSSA strains correlated well with the clinical manifestation in an MSSA outbreak in the NICU, supporting C elegans as a robust host model to study the pathogenesis of S aureus.

HISTORIQUE: Le Caenorhabditis elegans a déjà été utilisé comme modèle hôte pour déterminer la virulence des isolats de Staphylococcus aureus résistant à la méthicilline. Dans la présente étude, les chercheurs ont étudié les souches de S aureus susceptible à la méthicilline (SASM) associées à une flambée dans une unité de soins intensifs néonatals (USIN), au moyen du modèle de C elegans. MÉTHODOLOGIE: Les chercheurs ont repéré deux clones de flambée distincts au moyen de l'électrophérèse sur gel en champ pulsé, soit le SASM de type C et celui de type G, lors d'une flambée de SASM sur une période de sept mois à l'USIN du Sunnybrook Health Sciences Centre de Toronto, en Ontario. Le SASM de type C s'associait à une grave infection, tandis que celui de type G s'associait à une maladie moins invasive. Les chercheurs ont envoyé à Calgary, en Alberta, quatre isolats de type C représentatifs, trois de type G et trois isolats colonisés chez des nourrissons non liés à cette flambée, pour faire effectuer des tests de virulence à double insu dans le modèle hôte de C elegans et obtenir une meilleure caractérisation moléculaire. RÉSULTATS: Les souches de flambée invasive (type C) ont démontré une activité nématicide élevée, les souches de flambée non invasive (type G), une virulence intermédiaire et les isolats de colonisation non liés à la flambée, une avirulence ou une virulence faible dans le modèle de C elegans, ce qui se traduit par des taux de suppression moyens de 93,0 %, de 61,0 % et de 14,4 % le jour 9, respectivement, dans ces trois groupes de souches. Divers groupes de souches de SASM possédaient leur propre profil génétique unique et des profils géniques de virulence, mais tous les isolats du même groupe (type C ou type G) ont partagé des caractéristiques génétiques identiques et des schémas de virulence génique. CONCLUSIONS: La présente évaluation en insu a démontré que les activités nématicides des souches de SASM étaient bien corrélées avec la manifestation clinique lors d'une flambée de SASM à l'USIN, ce qui étaye la solidité du C elegans comme modèle hôte pour étudier la pathogenèse du S aureus.

Risk factors for SARS transmission from patients requiring intubation: a multicentre investigation in Toronto, Canada.

BACKGROUND: In the 2003 Toronto SARS outbreak, SARS-CoV was transmitted in hospitals despite adherence to infection control procedures. Considerable controversy resulted regarding which procedures and behaviours were associated with the greatest risk of SARS-CoV transmission. METHODS: A retrospective cohort study was conducted to identify risk factors for transmission of SARS-CoV during intubation from laboratory confirmed SARS patients to HCWs involved in their care. All SARS patients requiring intubation during the Toronto outbreak were identified. All HCWs who provided care to intubated SARS patients during treatment or transportation and who entered a patient room or had direct patient contact from 24 hours before to 4 hours after intubation were eligible for this study. Data was collected on patients by chart review and on HCWs by interviewer-administered questionnaire. Generalized estimating equation (GEE) logistic regression models and classification and regression trees (CART) were used to identify risk factors for SARS transmission. RESULTS: 45 laboratory-confirmed intubated SARS patients were identified. Of the 697 HCWs involved in their care, 624 (90%) participated in the study. SARS-CoV was transmitted to 26 HCWs from 7 patients; 21 HCWs were infected by 3 patients. In multivariate GEE logistic regression models, presence in the room during fiberoptic intubation (OR = 2.79, p = .004) or ECG (OR = 3.52, p = .002), unprotected eye contact with secretions (OR = 7.34, p = .001), patient APACHE II score > or = 20 (OR = 17.05, p = .009) and patient Pa0(2)/Fi0(2) ratio < or = 59 (OR = 8.65, p = .001) were associated with increased risk of transmission of SARS-CoV. In CART analyses, the four covariates which explained the greatest amount of variation in SARS-CoV transmission were covariates representing individual patients. CONCLUSION: Close contact with the airway of severely ill patients and failure of infection control practices to prevent exposure to respiratory secretions were associated with transmission of SARS-CoV. Rates of transmission of SARS-CoV varied widely among patients.

Utility of environmental sampling for the prevention of transmission of vancomycin resistant enterococci (VRE) in hospitals.

BACKGROUND: Although vancomycin resistant enterococci (VRE) have been shown to contaminate environmental surfaces in the room of a patient infected or colonized with VRE there is limited evidence that links environmental contamination with acquisition. OBJECTIVES: To determine whether a policy of environmental sampling and room closure is more effective than cleaning and visual inspection of the room without culturing, in preventing the transmission of VRE to the next admitted patient. METHODS: The rooms of consecutive patients with VRE were alternatively managed according to either Protocol I (terminal cleaning, inspection and admission of new patient(s)) or Protocol II (terminal cleaning, environmental cultures and closing of the room pending negative results). The next admitted patient to all rooms had rectal swabs obtained for VRE within 24 hours of admission, three to five days after admission and upon discharge from the room and/or the facility. The proportion of patients who acquired the same strain of VRE after being admitted to rooms handled according to either Protocol I or Protocol II was compared. RESULTS: The risk of acquisition of VRE by patients admitted to a room managed according to Protocol I (1/19) was not significantly different than for patients admitted to a room managed according to Protocol II (0/12) (p=0.99). At least one positive environmental culture was obtained in 8/14 (57.1%) rooms managed according to Protocol II. CONCLUSIONS: Although VRE may be detected in the hospital environment there is insufficient evidence to conclude that routinely obtaining negative environmental cultures from the room of a patient infected or colonized with the organism is more effective in preventing VRE transmission to subsequent patients, provided the room is adequately cleaned and disinfected.

The role of colonization pressure in nosocomial transmission of methicillin-resistant Staphylococcus aureus.

BACKGROUND: Colonized or infected patients are a major reservoir for patient-to-patient transmission of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. Despite attempted adherence to recommended infection prevention and control procedures, a general medicine unit in our hospital continued to experience ongoing transmission of MRSA. The role that colonization pressure (CP) plays in nosocomial transmission of MRSA on a general medicine unit was assessed, and a threshold CP above which additional IP&C practices should be implemented was proposed. METHODS: From January 2005 to December 2006, all patients admitted to a 36-bed general medicine unit were screened on admission for MRSA. Monthly MRSA nosocomial incidence (new nosocomial cases x 1000/susceptible patient-days) and CP (number of MRSA patient-days x 100/total patient-days) were calculated. The relative risk (RR) of MRSA transmission above and below the median CP with 95% confidence interval was calculated. RESULTS: Twenty-one cases of nosocomially acquired MRSA were detected during the study period, with transmission occurring in 8 separate months. The median CP during the 2 years was 6.7%. The RR of MRSA acquisition increased as CP increased above the median (RR, 7.6; 95% CI: 1.1-52.6; P = .008). MRSA outbreaks were declared on 2 separate occasions, and, in each, the CP for the preceding month was greater than the median value of 6.7%. CONCLUSION: CP has a significant effect on the subsequent transmission of MRSA on a general medicine unit. Ongoing monitoring of CP provides the opportunity for early implementation of enhanced infection prevention and control practices and can potentially decrease nosocomial transmission of MRSA and prevent outbreaks.

Neonatal group B streptococcal disease: incidence, presentation, and mortality.

OBJECTIVES: To ascertain the incidence, and compare the clinical characteristics, laboratory parameters, and immediate mortality of neonates with early-onset (symptomatic and asymptomatic) and late-onset group B streptococcal (GBS) disease. METHODS: A chart review of 81 neonates with GBS disease (either blood and/or cerebrospinal fluid culture-proven) born between 1995 and 2002 admitted to two tertiary care perinatal centers in Toronto was conducted. Clinical characteristics were compared for (1) asymptomatic early-onset, symptomatic early-onset, and late-onset GBS disease and (2) survivors and non-survivors. RESULTS: The incidence of GBS disease was 1.13/1000 live births. One or more antepartum or intrapartum predisposing factors were recognized in 62% of cases. Early-onset was noted in 65 (80%) neonates (23 asymptomatic and 42 symptomatic). All full-term infants survived. The mortality was 6% and was confined to preterm neonates with early symptomatic disease who presented with shock and had thrombocytopenia. CONCLUSION: Antepartum or intrapartum known predisposing risk factors of GBS disease were lacking in one third of patients. Patients who died were preterm infants in the early symptomatic group.

Evidence-based strategies to improve immunization compliance of postgraduate medical trainees at large academic-medical facilities.

The purpose of this evaluation is to assess the effectiveness of the modifications made by the University of Toronto Postgraduate Medical Education to improve medical trainee compliance with the immunization standards set forth in national guidelines, provincial regulations and protocols and university policy. Trainee compliance with immunization requirements were evaluated as of January 2003, 2004 and 2005. Statistically significant increases in compliance rates for all required immunizations--hepatitis B virus, measles, rubella and chicken pox--and tuberculosis skin tests were observed. University of Toronto postgraduate medical trainees are now highly compliant with the Hospital Management Regulation 965 of the Ontario Public Hospitals Act, Canadian Immunization Guide, Public Health Agency of Canada guidelines for prevention and control of occupational infections in healthcare and the University of Toronto Faculty of Medicine immunization policy.