Hands Of Personnel Research Articles

術前患者およびICU患者における咽頭および下気道菌叢の検討

Bacterial colonization of the pharynx before and one week after operation, and contamination of the trachea during intubation in 7 patients who underwent operations were investigated. And bacterial colonization of pharynx, tracheas, and mechanical-ventilators in 7 ICU patients was investigated. Flora of palms of 10 ICU personnel was also examined: 1) Oral bacteria began to be found in the trachea several hours after intubation. 2) In oropharyngeal flora, one week after operation, Neisseria and anaerobes which belong to normal flora decreased because of antibiotics, but no new resistant bacteria appeared. 3) Although isolates from pharynx of preoperative patients were normal flora, those of ICU patients were Staphylococcus epidermidis, Enterococcus spp., gram-negative rods such as Pseudomonas aeruginosa, and yeast liked organisms etc, which were resistant to antibiotics. 4) From the trachea of intubated patients in ICU, oral bacteria were isolated. 5) Pseudomonas pickettii was isolated from the expiratory side of ventilator circuits in one patient, but it was not isolated from the patient. 6) From hands of ICU personnel, gram-positive bacteria such as coagulase negative staphylococci, Coryne bacterium spp. and Bacillus spp. were isolated. 7) One patient in ICU, who developed pneumonia due to resistant Bacteroides fragilis following oropharyngeal colonization, was reported. These studies suggested the importance of environmental control, careful selection of antibiotics, and attention to change of flora.

Manual Ventilation Bags as a Source for Bacterial Colonization of Intubated Patients

A group of 14 intensive care unit (ICU) patients were studied to determine if manual ventilation bags (MVB) could serve as a source of bacterial or fungal pathogens that could colonize the respiratory tract of intubated patients. A total of 51 cultures were simultaneously obtained of patient's sputum, the exterior MVB surface, MVB port, and MVB interior (postexhalation valve). Pathogens colonizing or infecting the respiratory tract of intubated ICU patients were frequently simultaneously present on the exterior surface of the MVB and inside the MVB port used to connect the MVB with the endotracheal tube. In addition, coagulase-negative staphylococci and yeast were frequently present on the exterior surface of the MVB. The interior of the MVB was usually sterile. In three instances pathogens were isolated from the MVB before isolation from the patient's sputum. MVB may serve as a source for colonizing the respiratory tract of intubated ICU patients and/or the hands of medical personnel. The exterior surface and port of MVB should be cleaned of visible debris and disinfected at least once a day.

High-Level Gentamicin Resistance in Enterococcus: Microbiology, Genetic Basis, and Epidemiology

Antibiotic resistance is an ever-increasing problem in enterococci. These bacteria are remarkable in their ability to acquire and disseminate antibiotic resistance genes by a variety of routes. Since first described in 1979, high-level resistance to gentamicin (MIC, greater than 2,000 micrograms/mL) has spread worldwide and has been responsible for serious infections. Resistance is plasmid-mediated and due to aminoglycoside-modifying enzymes. High-level gentamicin resistance indicates that there will be no synergistic bactericidal activity with penicillin-gentamicin combinations. The epidemiology of nosocomial enterococcal infections is remarkably similar to that of nosocomial infections caused by methicillin-resistant staphylococci and by multidrug-resistant gram-negative bacilli. The most likely way these resistant bacteria are spread among hospital patients is via transient carriage on the hands of hospital personnel. Patient-to-patient and interhospital transmission of strains has been reported recently. However, clonal dissemination is not the cause of the increased frequency of resistant strains, since gentamicin resistance appears in a variety of different conjugative and nonconjugative plasmids in Enterococcus.

The epidemiology of enterococci

The enterococci are emerging as a significant cause of nosocomial infections, accounting for approximately 10% of hospital acquired infections. They are found as normal inhabitants of the human gastrointestinal tract, but may also colonize the oropharynx, vagina, perineal region and soft tissue wounds of asymptomatic patients. Until recently, evidence indicated that most enterococcal infections arose from patients' own endogenous flora. Recent studies, however, suggest that exogenous acquisition may occur and that person-to-person spread, probably on the hands of medical personnel, may be a significant mode of transmission of resistant enterococci within the hospital. The use of broad-spectrum antibiotics, especially cephalosporins, is another major factor in the increasing incidence of enterococcal infections. These findings suggest that barrier precautions, as applied with other resistant nosocomial pathogens, along with more judicial use of antibiotics may be beneficial in preventing nosocomial spread of resistant enterococci.

Evaluation of an antimicrobial soap formula for virucidal efficacy in vitro against human immunodeficiency virus in a blood-virus mixture.

The virucidal efficacy of a health care personnel hand wash product containing 0.5% parachlorometaxylenol in a sodium C14-16 olefin sulfonate formula was evaluated in in vitro tests with human immunodeficiency virus type 1 (HIV-1) in the presence of 50% whole human blood. The HTLV-IIIRF strain of HIV-1 was suspended in 50% medium-50% whole human blood and exposed to various dilutions of the hand wash product for 30 or 60 s. Following detoxification, residual infectivity was determined by a lytic cytopathogenic assay in MT2 cell cultures. No infectious HIV could be detected after a 30-s exposure to the hand wash product at dilutions of 1:5 and 1:10 and after a 60-s exposure at dilutions of 1:5, 1:10, 1:20, and 1:30. More than 99.9% of the virus was inactivated at these dilutions and exposure times.

New method for determination of efficacy of health care personnel hand wash products.

A method of studying the effects of health care personnel hand wash products is described. The fingernail regions of the hands of volunteers are inoculated with a mixture of Escherichia coli and Serratia marcescens, and the areas are dried for a standard time. After routine hand washing, each fingernail region is individually scrubbed with an electric toothbrush which moves longitudinally to the handle into collection fluid contained in a petri dish. The test bacteria in the fluid are then enumerated. (Bacillus subtilis spores may be included as tracers to show degree of physical removal of the procedure.) This method has several advantages over the frequently used glove juice technique. Experimental designs with large numbers of volunteers, multiple sampling sites, and many hand wash products may be performed. Ten sampling sites (fingers) are available, versus the two gloved hands for testing products. (Efficiency is almost 100% in the recovery of spore tracers placed on the fingernails.) Many commercial health care personnel hand wash products containing antimicrobial agents substantive to the skin do not rapidly reduce numbers of inoculated bacteria in the fingernail regions to any greater extent than nonantimicrobial hand washes. Products containing isopropanol or ethanol are very effective in decreasing bacteria in areas around and under the fingernails.

The Inanimate Environment of an Intensive Care Unit as a Potential Source of Nosocomial Bacteria: Evidence for Long Survival of Acinetobacter calcoaceticus

AbstractEnvironmental surface and personnel hand impression cultures were obtained during 13 sampling periods in the University of Virginia Pediatric Intensive Care Unit to document potential reservoirs of nosocomial pathogens. In 78 environmental cultures Staphylococcus aureus was found eight times and gram-negative bacilli ten times. The patient chart cover was the most commonly contaminated surface. Acinetobacter calcoaceticus was found in five of ten cultures positive for gram-negative bacilli. Thirty of 59 hand cultures were positive for S aureus and gram-negative bacilli; nurses and residents had both, respiratory therapists only gram-negative bacilli, and A calcoaceticus was the most commonly isolated bacterium of potentially nosocomial significance (14/30). Laboratory investigation of bacterial survival revealed that gramnegative bacilli survived on a dry formica surface from a few hours up to three days but Acinetobacter survived up to 13 days. Since A calcoaceticus has been implicated in many nosocomial infections, its long survival on a dry surface may be an additional factor in its transmission in hospitals and suggests that more attention be paid to environmental surfaces as a source of significant nosocomial pathogens.

The inanimate environment of an intensive care unit as a potential source of nosocomial bacteria: evidence for long survival of Acinetobacter calcoaceticus.

Environmental surface and personnel hand impression cultures were obtained during 13 sampling periods in the University of Virginia Pediatric Intensive Care Unit to document potential reservoirs of nosocomial pathogens. In 78 environmental cultures Staphylococcus aureus was found eight times and gram-negative bacilli ten times. The patient chart cover was the most commonly contaminated surface. Acinetobacter calcoaceticus was found in five of ten cultures positive for gram-negative bacilli. Thirty of 59 hand cultures were positive for S aureus and gram-negative bacilli; nurses and residents had both, respiratory therapists only gram-negative bacilli, and A calcoaceticus was the most commonly isolated bacterium of potentially nosocomial significance (14/30). Laboratory investigation of bacterial survival revealed that gram-negative bacilli survived on a dry formica surface from a few hours up to three days but Acinetobacter survived up to 13 days. Since A calcoaceticus has been implicated in many nosocomial infections, its long survival on a dry surface may be an additional factor in its transmission in hospitals and suggests that more attention be paid to environmental surfaces as a source of significant nosocomial pathogens.

Human Microvessel Endothelial Cell Isolation and Vascular Graft Sodding in the Operating Room

We have evaluated multiple factors inherent to an operating room-compatible endothelial cell procurement and sodding procedure. Microvessel endothelial cell isolations have been performed on fat tissue obtained from over 140 patients with a 100% success rate. Liposuction-derived fat was optimal with respect to cell yield, and isolation time. The devices and equipment used were acceptable to the operating room and the complete cell procurement procedure was successful even in the hands of personnel with minimal training. Fat digestion was achieved using crude clostridial collagenase, with an average cell yield of 1 x 10(6) microvessel endothelial cells/gm of fat. Evaluation of this procedure with canine fat using an operating room acceptable procedure resulted in a 100% procurement success rate requiring 1.5 hours (+/- .5 hrs) for completion of the fat isolation, and cell isolation procedure. Microvessel EC could subsequently be used in graft seeding or sodding techniques to establish endothelial cell monolayers on vascular grafts. Our results indicate that one person with minimal cell isolation background can reproducibly isolate large quantities of sterile autologous endothelial cells in the operating room for immediate use in endothelial cell seeding/sodding procedures.

The use of antiseptics for handwashing by medical personnel.

Numerous studies have shown that the major reservoir of nosocomial infection in the hospital is the infected or colonised patient and the major mode of spread of organisms between patients is on the hands of medical personnel. A prolonged preoperative scrub with an antiseptic is one of the most time-honoured rituals of surgical asepsis. Hygienic handwashing in the hospital or clinic, to remove transient contaminants acquired from patients or the environment and prevent cross-infection to vulnerable patients, is similarly regarded as one of the most fundamental infection control measures, yet is done infrequently by personnel in most hospitals. Following a typical brief (7.10 second) handwashing with a nonmedicated soap, the number of organisms that can be transmitted from the person's hands may, paradoxically, actually increase. Use of chlorhexidine for handwashing or application of an evaporative alcohol-based lotion has been found to reduce shedding of bacteria-laden skin squames. Routine use of antiseptic-containing handwashing agents is clearly more effective than nonmedicated soaps for microbial removal, can enhance the value of the handwashings that are done and might further confer protection against contaminants acquired between handwashings. In a sequential comparative trial of three handwashing agents in a surgical intensive care unit--a nonmedicated soap, 10% povidone-iodine solution, and 4% aqueous chlorhexidine, each used exclusively for approximately six weeks--the incidence of nosocomial infection was 50% lower during the use of the antiseptic handwashing products than during the use of nonmedicated soap (P less than .001). Novel approaches are needed to improve the frequency of hygienic handwashing.(ABSTRACT TRUNCATED AT 250 WORDS)

Sink flora in a long-stay hospital is determined by the patients' oral and rectal flora.

Sinks in a new long-stay hospital (LSH) were cultured weekly during 4 consecutive months to evaluate the microbial profile before and after occupancy of the hospital. From the elderly patients admitted to the patient care rooms oral and rectal specimens were collected to examine the contribution of the patients' flora to the sink contamination. Isolates were typed biochemically, serologically and by susceptibility pattern. Before occupancy Gram-negative bacilli were not isolated. Once the elderly patients, who were highly colonized on admission, occupied their rooms identical strains gradually contaminated the sinks. Escherichia coli, Klebsiella, Pseudomonas and Acinetobacter species were the major correlating strains. The mean concentration of the correlating isolates was higher in throat and intestines compared to the mean concentration of the non-correlating strains. These strains seem to have a greater chance to be shed and then transferred via the hands of personnel to sinks. This report shows that the major route of environmental contamination is from patient carriers to sinks, and not the reverse way.

Advances in prehospital immediate care

Although studies documenting the influence of prehospital care on patient outcome are most urgently needed, recent techniques and innovations being examined in the field setting may improve the clinical care delivered. The basic manoeuvres for airway and breathing have been in need of emphasis for some time. Sellick's manoeuvre has been resuscitated and is being emphasized in most training programmes. Bag-mask ventilation, notoriously difficult in field settings in the hands of emergency medical personnel, has been improved with the recent improvement of mask design. Endotracheal intubation has been shown to influence patient outcome, and can be performed with surprising success by paramedics. Complication rates continue to cause concern, and a study to document the incidence of tube misplacement has just begun in the United States and Canada. Transillumination and translaryngeal jet ventilation have been refined as adjunct techniques to field intubation. Patient monitoring has improved through the more common use of pulse oximetry and a recently-introduced "CO2 Detector" that is designed to indicate via a colour change, oesophageal placement of an endotracheal tube. Automatic external defibrillators have come under some scrutiny, and early data suggest their safe use by lay persons, a minimal effect on outcome in high-risk patients, and a significant effect on outcome only when combined with other essential elements of prehospital care. The role of IV fluids in prehospital trauma care has been clarified, as well as that of the pneumatic antishock garment. Transcutaneous pacemakers have been developed and shown effective if used early, and thrombolytic therapy has been examined for the prehospital management of acute myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

THE EPIDEMIOLOGY OF GENTAMICIN-RESISTANT PSEUDOMONAS AERUGINOSA ON AN INTERMEDIATE CARE UNIT

The authors conducted a prospective six-month study of colonization by gentamicin-resistant Pseudomonas aeruginosa on an intermediate care unit at a Cleveland, Ohio hospital with the use of selective culture techniques, serotyping, and plasmid analysis. Thirty-five of 163 patients (21%) were culture positive at least once for gentamicin-resistant Pseudomonas aeruginosa. Patient samples, environmental cultures, and personnel hand cultures revealed no common source for the organisms. Plasmid profiling added little to the serotyping data. Only nonambulation and length of stay on the unit were significant independent risk factors for colonization with gentamicin-resistant Pseudomonas aeruginosa by multiple logistic regression analysis. Age, use of urinary catheters, exposure to antibiotics, and duration of antibiotic use were correlated with one or both of the independent risk factors, but were not themselves independently associated with colonization by these resistant organisms. Cross-colonization apparently was not an important mode of dissemination of gentamicin-resistant Pseudomonas aeruginosa on this intermediate care unit. The identified risk factors appear to be more important than cross-colonization, and control strategies should address these issues.

Epidemiology of Clostridium difficile Colonization in Newborns: Results Using a Bacteriophage and Bacteriocin Typing System

We used a typing system based on bacteriophage and bacteriocin susceptibility to study the epidemiology of Clostridium difficile colonization of newborn infants. C. difficile was found in the stools of 30 (16.0%) of 187 infants who were screened. Increased length of stay in the nursery (P less than .001) and delivery by cesarian section (P less than .001) were associated with higher rates of colonization. The isolates initially detected from the environment and the infants were strain B1811-1700. Strain B1537/Cld7 became the predominant isolate obtained from the infants; positive cultures were also obtained from the environment and the hands of personnel who worked in the nursery and had strain B1537/Cld7. Our results suggest that the infants acquired C. difficile through transfer from the hands of hospital staff.

Brief Report: The Detection of Blood on Gloved Hands of Central Sterile Supply Personnel and Cleaned Instruments Used for Procedures on Patient Units

Patient blood is recognized as a dangerous substance because it may contain infectious agents. While the practice of gloving provides some protection to hospital personnel exposed to instruments contaminated with patient blood, frequent breaks in techniques occur in which personnel inadvertently touch surfaces and objects in the environment with the potentially contaminated gloves. Also, “cleaned” instruments are placed on environmental surfaces to which other personnel are exposed. The purpose of this study was to determine the frequency of blood contamination of “cleaned” instruments used for patient procedures in the hospital, and on the gloved hands of central sterile supply (CSS) personnel handling those instruments.

Brief Report: The Detection of Blood on Gloved Hands of Central Sterile Supply Personnel and Cleaned Instruments Used for Procedures on Patient Units

Patient blood is recognized as a dangerous substance because it may contain infectious agents. While the practice of gloving provides some protection to hospital personnel exposed to instruments contaminated with patient blood, frequent breaks in techniques occur in which personnel inadvertently touch surfaces and objects in the environment with the potentially contaminated gloves. Also, “cleaned” instruments are placed on environmental surfaces to which other personnel are exposed. The purpose of this study was to determine the frequency of blood contamination of “cleaned” instruments used for patient procedures in the hospital, and on the gloved hands of central sterile supply (CSS) personnel handling those instruments.

Equipment-related infections—national policies

Hospital equipment remains a common cause of infection, via contact with the patient’s body or body fluids or with the hands of hospital personnel. The occurrence of outbreaks to contaminated equipment is often the basis for concern about medical equipment as a cause of endemic nosocomial infections. Such outbreaks do not necessarily indicate a significant contribution overall to the problem of nosocomial infections, but stimulate us to improve methods of decontamination, disinfection and sterilization of equipment. Most outbreaks are associated with person-to-person spread or due to contamination of an item that should be sterile. Infection Control Committees were established in Spanish hospitals in the late sixties, following work by Moreno Lopez, Ales, Baquero and others regarding bacterial resistance to antibiotics. At that time, few hospitals had a written policy on decontamination, disinfection and sterilization and procedures were left to poorly trained nurses. With the recognition of outbreaks of nosocomial infection related to equipment in Intensive Care Units, there was greater interest and concern and many Infection Committees established procedures to prevent related infections. Twenty years ago we did not have infection control programmes; the role of most microbiologists was mainly benchwork and very little clinical practice; nurses were poorly trained-except for aspects of direct patient care and manufacturers of equipment played a non-existent role in decontamination or sterilization of their own machines and devices. In the early seventies Departments of Preventive Medicine were established in most of our large hospitals. These were required to promote the health of hospital personnel workers, provide a basis for environmental control, establish an infection control programme and provide epidemiological data within the hospital. Most departments were hampered by inadequate premises and shortage of specialized personnel and a few accomplished these aims. Our Department of Preventive Medicine in Madrid, was established in 1975 and has co-ordinated activities for occupational health, environmental services, hospital infection laboratory, hospital hygiene, infection control, and infectious diseases. It has served as a basis for research and

Nosocomial cytomegalovirus infections within two hospitals caring for infants and children.

Using serology, virology, and molecular epidemiology, we investigated nosocomial transmission of cytomegalovirus (CMV) over a two-year period in two contrasting environments: a crowded, busy pediatric chronic care unit (337 patients, 43 nurses, and 76 therapists; average prevalence of CMV excretion in patients, 16%) and a small neonatal unit (293 patients and 69 nurses; average prevalence, 0.7%). In the chronic care unit no nurse or therapist acquired CMV, but two pairs of infants were infected with homologous strains of CMV, and patient-to-patient transmission was proven in one pair. In the neonatal unit no patients acquired CMV in the hospital, but two nurses seroconverted, with a nonoccupational source proven for one. Transmission from CMV-infected caretaker to patient did not occur in either environment. CMV was isolated from diapers as well as hands of patients and personnel but not from other environmental surfaces.

Unusual occurrence of an epidemic of type Ib/c group B streptococcal sepsis in a neonatal intensive care unit.

An epidemic of late-onset sepsis due to type Ib/c group B Streptococcus (Ib/c-GBS) occurred in a neonatal intensive care unit (NICU). During a seven-week period, five very low birth weight infants (index cases [ICs]) more than four weeks of age became bacteremic. Bacteriologic surveillance of neonates revealed persistent colonization in three ICs and identified three asymptomatic carriers (ACs). All ICs and one AC acquired Ib/c-GBS nosocomially, whereas the other two ACs were colonized at birth. Among nursery personnel, 39% carried GBS, but only two harbored Ib/c-GBS. Although phage typing of Ib/c-GBS isolates identified two patterns of susceptibility, we believe a single strain was involved in the epidemic, because the patterns overlapped and most isolates carried the same lysogenic phage. Analysis of events suggested infant-to-infant spread via the hands of personnel, but acquisition from the colonized staff was also possible. The control measures instituted prevented further spread of Ib/c-GBS in the NICU.

Epidemic septic arthritis caused by Serratia marcescens and associated with a benzalkonium chloride antiseptic.

During a 6-week period, 10 patients were admitted to a hospital for treatment of knee or shoulder joint infections due to Serratia species. Isolates from eight patients were identified as Serratia marcescens with identical biochemical characteristics and antibiotic susceptibility patterns. Before the onset of infections, all patients had been treated by two orthopedic surgeons who shared an office. Studies revealed that infections were associated with previous joint injections (P = 4.44 X 10(-5] of methylprednisolone and lidocaine. Environmental cultures revealed that a canister of cotton balls soaked in aqueous benzalkonium chloride and two multiple-dose vials of methylprednisolone previously used by office personnel were contaminated with the epidemic strain of S. marcescens. The canister may have served as a potential reservoir for contamination of sterile solutions and equipment used for joint injections, of skin at the injection site, and of hands of personnel. No further cases occurred after the use of aqueous benzalkonium chloride was discontinued.