The contamination of gowns in an intensive care unit

Lowbury Lecture 2005: infection control from a global perspective

All healthcare settings around the world face the problem of healthcare-associated infections (HCAIs). Rates of infection vary between countries and within the same country depending on resources, interest of caregivers and healthcare staff, and patients' socio-economic situation. According to recent publications, 10-70% of HCAIs are preventable. Failure to comply with guidelines on hand hygiene, glove and gown use, and barrier nursing is a problem and unnecessary infection control measures are costly. National legislations and regional, national and international standards and guidelines associated with infection control also have an impact for countries that are not directly involved. They should be based on the assessment of infection risk, and should not increase costs unnecessarily. The International Federation of Infection Control and national infection control societies play an important role in continuing the education of infection control specialists.

Does routine gowning reduce nosocomial infection and mortality rates in a neonatal nursery? A Singapore experience

A 1 year prospective study on routine gowning before entering a neonatal unit was conducted in a maternity hospital in Singapore. This study was done based on previous work by Donowitz, Haque and Chagla and Agbayani et al., as there have been no known studies done in Singapore. The aim of the study was to test the hypothesis that routine gowning before entering a neonatal nursery does not reduce nosocomial infection and mortality rate. A total of 212 neonates from the neonatal intensive care unit (NICU) and 1694 neonates from the neonatal special care unit (NSCU) were studied. Neonates admitted during the 1 year study were assigned to the gowning (control) and no routine gowning (trial) group on every alternate 2 months. The hospital infection control nurse provided data on nosocomial infection. The overall nosocomial infection rate in the NICU was 24% (25 of 104 admissions) during gowning periods compared to 16.6% (18 of 108 admissions) when plastic aprons were not worn before entry. In the NSCU, the overall infection rate was 1.5% (12 of 800 admissions) during gowning periods compared to 2.1% (19 of 894 admissions) when no gown was worn before entry. Results of the study found no significant differences in the incidences of nosocomial infection and mortality in the neonates. The cost of gowns used during the no routine gowning periods was S$2012.8 compared to S$3708 used during the routine gowning procedure. The investigators recommend that routine gowning before entering a neonatal unit is not essential and cost effective for the purpose of reducing infection. Rather the focus should be on adequate handwashing by all hospital personnel and visitors before handling neonates.

Staphylococcus aureus: a review of the literature

Staphylococcus aureus has a long association with nosocomial infection. Problems date from the 1950s, although methicillin-resistant Staphylococcus aureus (MRSA) did not emerge until the following decade. Initially the pathogenicity of antibiotic-resistant strains was underestimated, and is still sometimes questioned, but today most authorities consider MRSA a serious threat, especially given current preoccupation with cost-effectiveness within the health service: nosocomial infection is associated with increased expenditure and may be regarded as a hallmark of indifferent nursing and medical care. This review documents the emergence of MRSA and recognition of the ensuing problems throughout the 1980s and early 1990s, with suggestions for nursing activities which could contribute towards improved control. Lessons learnt during outbreaks are seen to be of value, but there is also a need for staff at ward level to review routine practice continually so that awareness of activities likely to result in cross-infection is maintained. The use of protective clothing emerges as less important than handwashing, which may be periodically audited to maintain standards.

Daily scrub with chlorhexidine reduces skin colonization by antibiotic-resistant Staphylococcus epidermidis

The aim of this study was to establish whether long-term use of chlorhexidine would prevent skin colonization by antibiotic-resistant Staphylococcus epidermidis. Ten nurses, working on a ward for haematological disorders, volunteered to participate in the test. They washed one arm every morning for three weeks with chlorhexidine gluconate, ('Hibiscrub' ICI Pharmaceuticals). The other arm served as a negative control. Samples from the antecubital fossa of both arms were taken two to three times a week during the wash period and two weeks thereafter, giving a total of 216 samples. The appearance of resistant S. epidermidis with different antibiograms was analysed. During the wash period the total bacterial counts and the counts of the resistant S. epidermidis strains on the test arm were both about one-tenth of those on the control arm, a significant difference (P < 0.05). Moreover, there were significantly fewer resistant S. epidermidis on the test arm, 1.3 per sample, than on the control arm, 2.5 per sample (P < 0.01). Most of the resistant S. epidermidis were only found once or a few times on the same site, after which they disappeared, though a few persisted on the skin even during 'Hibiscrub' washing. In an agar dilution test, chlorhexidine minimum inhibitory concentrations (MICs) of persisting strains were the same as for strains disappearing from the skin following 'Hibiscrub' washing, 1.0 or 2.0 mg l-1, but somewhat higher than MICs of strains isolated from healthy carriers outside the hospital whose MICs were 0.5 mg l-1. The relative contribution to the skin counts by those S. epidermidis strains found only occasionally were compared with those found repeatedly but no difference in reduction was found between these categories during 'Hibiscrub' washing.

Microbial flora on doctors' white coats

OBJECTIVE

To determine the level and type of microbial contamination present on the white coats of doctors in order to assess the risk of transmission of pathogenic micro-organisms by this route in a hospital setting.

DESIGN

Cross sectional survey of the bacterial contamination of white coats in a general hospital.

SETTING

East Birmingham Hospital, an urban general hospital with 800 beds.

SUBJECTS

100 doctors of different grades and specialties.

RESULTS

The cuffs and pockets of the coats were the most highly contaminated areas. The level of bacterial contamination did not vary with the length of time a coat had been in use, but it increased with the degree of usage by the individual doctor. Staphylococcus aureus was isolated from a quarter of the coats examined, more commonly from those belonging to doctors in surgical specialties than medical specialties. Pathogenic Gram negative bacilli and other pathogenic bacteria were not isolated.

CONCLUSIONS

White coats are a potential source of cross infection, especially in surgical areas. Scrupulous hand washing should be observed before and after attending patients and it may be advisable to remove the white coat and put on a plastic apron before examining wounds. There is little microbiological reason for recommending a more frequent change of white coat than once a week, nor for excluding the wearing of white coats in non-clinical areas.

The role of barrier precautions in infection control

Barrier precautions are a fundamental component of any infection control strategy and a critical aspect of all isolation systems. Because many infections are transmitted from patient-to-patient via the hands of personnel, gloves and gowns are widely recommended to provide an extra measure of protection against cross-infection. It is not clear whether gloves are superior to handwashing (if performed obsessionally) in this respect, and there is little evidence that gowns confer additional benefit. These concerns notwithstanding, barrier precautions can substantially reduce the risk of some infections, such as respiratory syncytial virus disease. On the other hand, the modes of transmission of many infections are complex (e.g. with rotavirus) or controversial (e.g. with rhinovirus), and, even though hands are involved in transmission, barrier precautions alone may not suffice to prevent spread. Moreover, neither gloves nor gowns can prevent nosocomial infections caused by endogenous microbial flora; perhaps this explains the limited efficacy of barrier precautions in reducing the endemic rate of infection due to bacteria such as Pseudomonas aeruginosa in intensive care units. Barrier precautions may also fail if colonized patients are not identified promptly. One potential solution to this problem is 'body substance isolation' (BSI), in which all patients are considered to be potential carriers of nosocomial pathogens whether or not they have been cultured or have developed a clinical infection. In BSI barrier techniques are used when any potentially contaminated patient material is handled. BSI also provides barrier protection from bloodborne pathogens for personnel.(ABSTRACT TRUNCATED AT 250 WORDS)

Reduction of nosocomial infection during pediatric intensive care by protective isolation

To determine whether simple protective isolation reduces the incidence of nosocomial bacterial and fungal infection during pediatric intensive care, we randomly assigned 70 children who were not immuno-suppressed and who required mechanical ventilatory support and three or more days of intensive care to receive standard care (n = 38) or protective isolation (n = 32) with use of disposable, non-waven, polypropylene gowns and nonsterile latex gloves. Risk factors predisposing patients to infection were comparable in the two groups. Nosocomial colonization occurred later among isolated patients (median, vs. 7 days; P less than 0.01) and was associated with subsequent infection in 12 patients, as compared with 12 patients given standard care (P = 0.01). Among patients who were isolated, the interval before the first infection was significantly longer than (median, 20 vs. 8 days; P = 0.04), the daily infection rate was 2.2 times lower than (95 percent confidence interval, 1.2 to 4.0; P = 0.007), and there were fewer days with fewer (13 percent vs. 21 percent; P = 0.001). The benefit of isolation was most notable after seven days of intensive care. Isolation was well tolerated by patients and their families. Regular monitoring showed that the children in each group were touched and handled comparably often by hospital personnel and family members. We conclude that the use of disposable, high-barrier gowns and gloves for the care of selected, high-risk children who require prolonged intensive care significantly reduces the incidence of nosocomial infection, is well tolerated, and does not compromise the delivery of care.

Bacterial counts on fabrics: a comparative study of three methods

One contact plate and two homogenization methods have been compared for efficiency in assessing the bacterial contamination of fabrics with high or low, natural or artificial contamination. The contact plate method resulted in considerably lower counts than any of the homogenization methods, which closely resembled one another. One of these, utilizing a Stomacher 400, was found to be more practical, and is therefore recommended for counting bacteria on fabrics.

Contamination of protective clothing and nurses' uniforms in an isolation ward

Staphylococcus aureus was frequently isolated, usually in small numbers, from cotton gowns (12.6 per cent), plastic aprons (9.2 per cent) and nurses' uniforms (15 per cent). Gram-negative bacilli were infrequently isolated. Contamination of the protective clothing did not increase when used over periods of up to 11 days. Fewer organisms were recovered from the front of nurses' uniforms when plastic aprons instead of gowns were worn, but gowns provided better shoulder protection. However, no differences were observed in isolations of Staph, aureus or Gram-negative bacilli from these sites.