What is essential remains invisible to the eyes? Blood pressure cuffs colonized by bacterial diversity.

Using sphygmomanometers to measure blood pressure is a common practice in the healthcare context. The disinfection and maintenance of these devices is essential in clinical practice to prevent the proliferation of microorganisms. The aim of this study was to determine the presence of pathogenic microorganisms in sphygmomanometer cuffs in the clinical setting. A cross-sectional study was carried out. Five types of healthcare centers, selected through convenience sampling, participated in this study. Samples were collected from the inside of sphygmomanometer cuffs, and labeled and delivered to the laboratory for analysis. The samples were incubated in an oven at 35.5 °C for 24 h. A total CFU count was carried out on the plates that were cataloged as positive. Colonies that showed growth were identified using the matrix-assisted laser desorption/ionization-mass spectrometry technology. Of the total sample, (N = 372), 69.1% were positive and were isolated. In 30.9% (n = 115), no bacterial development was found within 48 h. A total of 257 microorganisms were found. The mean number of colony-forming units was 29.62 (SD = 32.33). The socio-health centers had the highest amount of bacterial contamination in the cuffs. In regards to the type of microorganisms, 31.5% (n = 81) found were Bacillus cereus, followed by 26.8% (n = 69) of Staphylococcus hominis and 9.7% (n = 25) were Pantoea agglomerans, among others. Statistically significant differences were found between the type of microorganism and the hours elapsed since the last disinfection (X2(19) = 44.582; p = 0.001). Statistically significant differences were found between the time elapsed since the last disinfection and the type of sphygmomanometer (X2 (2) = 117.752; p = 0.000). Despite the fact that most hospitals and health centers have established infection control policies and protocols, the results of this study indicate the presence of pathogenic microorganisms in blood pressure cuffs in the clinical setting.

Sphygmomanometers and thermometers as potential fomites of Staphylococcus haemolyticus: biofilm formation in the presence of antibiotics

BACKGROUND The association between Staphylococcus haemolyticus and severe nosocomial infections is increasing. However, the extent to which fomites contribute to the dissemination of this pathogen through patients and hospital wards remains unknown. OBJECTIVES In the present study, sphygmomanometers and thermometers were evaluated as potential fomites of oxacillin-resistant S. haemolyticus (ORSH). The influence of oxacillin and vancomycin on biofilm formation by ORSH strains isolated from fomites was also investigated. METHODS The presence of ORSH on swabs taken from fomite surfaces in a Brazilian hospital was assessed using standard microbiological procedures. Antibiotic susceptibility profiles were determined by the disk diffusion method, and clonal distribution was assessed in pulsed-field gel electrophoresis (PFGE) assays. Minimum inhibitory concentrations (MICs) of oxacillin and vancomycin were evaluated via the broth microdilution method. Polymerase chain reaction (PCR) assays were performed to detect the mecA and icaAD genes. ORSH strains grown in media containing 1/4 MIC of vancomycin or oxacillin were investigated for slime production and biofilm formation on glass, polystyrene and polyurethane catheter surfaces. FINDINGS ORSH strains comprising five distinct PFGE types were isolated from sphygmomanometers (n = 5) and a thermometer (n = 1) used in intensive care units and surgical wards. ORSH strains isolated from fomites showed susceptibility to only linezolid and vancomycin and were characterised as multi-drug resistant (MDR). Slime production, biofilm formation and the survival of sessile bacteria differed and were independent of the presence of the icaAD and mecA genes, PFGE type and subtype. Vancomycin and oxacillin did not inhibit biofilm formation by vancomycin-susceptible ORSH strains on abiotic surfaces, including on the catheter surface. Enhanced biofilm formation was observed in some situations. Moreover, a sub-lethal dose of vancomycin induced biofilm formation by an ORSH strain on polystyrene. MAIN CONCLUSIONS Sphygmomanometers and thermometers are fomites for the transmission of ORSH. A sub-lethal dose of vancomycin may favor biofilm formation by ORSH on fomites and catheter surfaces.

Sphygmomanometers and thermometers as potential fomites of Staphylococcus haemolyticus: biofilm formation in the presence of antibiotics.

BACKGROUND: The association between Staphylococcus haemolyticus and severe nosocomial infections is increasing. However, the extent to which fomites contribute to the dissemination of this pathogen through patients and hospital wards remains unknown. OBJECTIVES: In the present study, sphygmomanometers and thermometers were evaluated as potential fomites of oxacillin-resistant S. haemolyticus (ORSH). The influence of oxacillin and vancomycin on biofilm formation by ORSH strains isolated from fomites was also investigated. METHODS: The presence of ORSH on swabs taken from fomite surfaces in a Brazilian hospital was assessed using standard microbiological procedures. Antibiotic susceptibility profiles were determined by the disk diffusion method, and clonal distribution was assessed in pulsed-field gel electrophoresis (PFGE) assays. Minimum inhibitory concentrations (MICs) of oxacillin and vancomycin were evaluated via the broth microdilution method. Polymerase chain reaction (PCR) assays were performed to detect the mecA and icaAD genes. ORSH strains grown in media containing 1/4 MIC of vancomycin or oxacillin were investigated for slime production and biofilm formation on glass, polystyrene and polyurethane catheter surfaces. FINDINGS: ORSH strains comprising five distinct PFGE types were isolated from sphygmomanometers (n = 5) and a thermometer (n = 1) used in intensive care units and surgical wards. ORSH strains isolated from fomites showed susceptibility to only linezolid and vancomycin and were characterised as multi-drug resistant (MDR). Slime production, biofilm formation and the survival of sessile bacteria differed and were independent of the presence of the icaAD and mecA genes, PFGE type and subtype. Vancomycin and oxacillin did not inhibit biofilm formation by vancomycin-susceptible ORSH strains on abiotic surfaces, including on the catheter surface. Enhanced biofilm formation was observed in some situations. Moreover, a sub-lethal dose of vancomycin induced biofilm formation by an ORSH strain on polystyrene. MAIN CONCLUSIONS: Sphygmomanometers and thermometers are fomites for the transmission of ORSH. A sub-lethal dose of vancomycin may favor biofilm formation by ORSH on fomites and catheter surfaces.

Sphygmomanometer cuffs: a potential source of infection!

We evaluated the potential pathogenic hazard of sphygmomanometer blood pressure cuffs (BPCs) in a hospital setting. Prospectively, the presence of bacterial organisms on 120 BPCs in 14 medical wards and outpatient clinics in a district general hospital in London was assessed. Swabs taken from the inner aspect of the cuffs were cultured using standard microbiological techniques. Bacterial organisms were found in 85% (102) of the 120 BPCs assessed. The highest rates of contamination were found in the outpatients department (90%). There were differences in the most common bacterial species isolated between the samples obtained from the outpatient clinics and the wards, with coagulase-negative Staphylococcus and diphtheroids being the most prevalent species in the wards and outpatient clinics, respectively. These findings highlight the necessity to eliminate this potential risk of infection.

Management and control of a carbapenem-resistant Acinetobacter baumannii outbreak in an intensive care unit.

OBJECTIVE: We had for aim to describe the identification and management of a 14-clonal carbapenem-resistant Acinetobacter baumannii (CRAB) outbreak, following admission of a known CRAB-infected patient in an ICU. METHODS: We reviewed the carriers' files and outbreak management procedures. RESULTS: The index patient was admitted with strict isolation precautions. The outbreak started 2 months after his discharge. It persisted despite reinforcement of strict isolation precautions, staff and patient cohorting, and extensive environmental decontamination including 2 rounds of routine terminal cleaning and disinfection or 1 round of cleaning and disinfection followed by hydrogen peroxide treatment. A second epidemic peak, after 4 weeks without any case, led to another wide environmental sampling and decontamination rounds. The source of the CRAB outbreak was suspected to be the blood pressure cuffs Velcro. Switching to cuffs submersible in a disinfectant stopped the outbreak. CONCLUSIONS: CRAB outbreaks are difficult to manage and sources of persistent colonization can be unexpected.

Blood pressure cuffs as a vector for transmission of multi-resistant organisms: colonisation rates and effects of disinfection.

OBJECTIVE: Blood pressure (BP) cuffs are potential vectors for transmission of multi-resistant organisms (MROs). The present study aims to determine MRO colonisation rates in BP cuffs from areas of high patient flow as an assessment of the quality of disinfection and infection control practices. METHODS: BP cuffs in the ED, high dependency unit (HDU) and operating theatres (OT) were prospectively examined after routine disinfection procedures. Swabs collected from the inner and outer surfaces of BP cuffs during inter-patient intervals were plated onto replicate organism detection and counting, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) chromogenic agar plates to detect rates of bacterial, MRSA and VRE colonisation, respectively. RESULTS: High bacterial colonisation rates were detected in BP cuffs from all three areas. BP cuffs from OT were significantly less colonised compared with cuffs from HDU and ED; 76% versus 96% and 100% (P < 0.0001) for inner surfaces and 86% versus 98% and 100% (P < 0.0001) for outer surfaces, respectively. Equivalent or higher bacterial growth was observed on the inner surface compared with outer surface in 54%, 84% and 86% of BP cuffs from OT, HDU and ED, respectively. MRSA was detected in 3 of 150 (2%) swabs collected, but no VRE was detected. CONCLUSION: Although MRSA and VRE were infrequently isolated, current disinfection and infection control protocols need to be improved given the greater recovery of organisms from the inner compared with outer surfaces of BP cuffs.

The potential for transmission of hospital-acquired infections by non-critical medical devices: the role of thermometers and blood pressure cuffs.

Healthcare-associated infection (HAI) is a major but often neglected public health problem. Most attention to HAI prevention is given to high-risk invasive diagnostic and therapeutic healthcare tools, while the importance of less critical tools tends to be underestimated. This study was designed to assess the potential contributory role played by thermometers and blood pressure cuffs in HAI transmission in a Nigerian teaching hospital. Analysis of swabs from thermometers and blood pressure cuffs used in the teaching hospital was conducted using standard microbiological techniques.

Bacterial contamination of stethoscopes with antimicrobial diaphragm covers.

Antimicrobial stethoscope covers impregnated with silver ions have been developed to prevent surface contamination and potential transmission of bacterial pathogens to patients. To test their practical utility, covers were distributed with the manufacturers' recommendations to a mixed group of health care professionals in a medical/surgical intensive care unit and an emergency department. Seventy-four clinicians were selected from a convenience sample for surface cultures and standard questioning regarding cleaning and cover use. Surface colony counts were significantly lower for uncovered stethoscope diaphragms (mean, 71.4 colonies) compared with covers used 1 week old (mean, 335.6 colonies). After controlling for type of clinician, frequency of stethoscope cleaning, and method of stethoscope cleaning, only the presence of a stethoscope cover was associated with higher colony counts (P<.0001). We question the practical utility of the antimicrobial diaphragm covers evaluated in this study for reducing the surface colonization of potentially harmful microorganisms.

Blood pressure cuff as a potential vector of pathogenic microorganisms: a prospective study in a teaching hospital.

OBJECTIVE: To investigate the potential role of blood pressure (BP) cuffs in the spread of bacterial infections in hospitals. DESIGN: A comprehensive, prospective study quantitatively and qualitatively evaluating the bacterial contamination on BP cuffs of 203 sphygmomanometers in use in 18 hospital units from January through March 2003. SETTING: A university hospital with surgical, medical, and pediatric units. RESULTS: A level of contamination reaching 100 or more colony-forming units per 25 cm(2) was observed on 92 (45%) of inner sides and 46 (23%) of outer sides of 203 cuffs. The highest rates of contamination occurred on the inner side of BP cuffs kept in intensive care units (ICUs) (20 [83%] of 24) or on nurses' trolleys (27 [77%] of 35). None of the 18 BP cuffs presumed to be clean (ie, those that had not been used since the last decontamination procedure) had a high level of contamination. Potentially pathogenic microorganisms were isolated from 27 (13%) of the 203 BP cuffs: 20 of these microorganisms were Staphylococcus aureus, including 9 methicillin-resistant strains. The highest rates of contamination with potentially pathogenic microorganisms were observed on cuffs used in ICUs and those kept on nurses' trolleys. For 4 patients with a personal sphygmomanometer, a genetic link was found between the strains isolated from the BP cuffs and the strains isolated from the patients. CONCLUSIONS: The results of this survey highlight the importance of recognizing BP cuffs as potential vectors of pathogenic bacteria among patients and as a source of reinfection when dedicated to a single patient, emphasizing the urgent need for validated procedures for their use and maintenance.

[Application of the sphygmogram in evaluation of pilots' cardiovascular function in resting condition].

With the purpose of exploring a new method for aerospace medical monitoring, a newly developed method--sphygmogram was used in 169 pilots. The results showed that these pilots could be divided into three types by the features of their resting sphygmogram. Among them, with respect to their cardiovascular function, 71 (about 42%) were "completely normal", 79 were "essentially normal", and 19 had some changes in cardiovascular function. It is considered that the status of cardiovascular function of the pilots can be distinguished with the newly developed method of sphygmogram. It suggests that it is important to make dynamic observations of pilots' cardiovascular function and strengthen the medical care for those who show certain changes in their cardiovascular function as revealed by the sphygmogram.