Literature Update - December, 2006
Compiled by Dr Emma McBryde, VICNISS ID Physician
New HICPAC guidelines for management of multi-drug-resistant
organisms (MDROs) in hospitals.
Last updated in 1996, new guidelines have been released by HICPAC - publicly available
on the CDC website.
Issues discussed include the role of healthcare workers in introducing or transmitting
MDROs and the importance of community MRSA. The importance of the healthcare structure
and administrative support for successful infection control and prevention is emphasized
throughout.
One of the major focuses of the paper was active surveillance cultures. No specific
recommendations were made, and the conflicting evidence in the literature was highlighted.
Rather, the guideline suggested that active surveillance cultures (ASCs) may be
useful in some settings especially when other control methods have failed. Guidelines
were given for the staff support necessary for ASCs.
In the last guidelines in 1996, it was stated that 3 negative swabs was sufficient
to conclude a patient was no longer colonized. The 2006 guidelines are less emphatic.
The authors repeated the 1996 statement, but recommended that this not be applied
in outbreak settings or when patients had risk factors for persistent colonization,
such as exposure to antibiotics or a draining wound.
The review also responded to some recently published data that suggests environmental
decontamination is effective at reducing prevalence of VRE and recommended environmental
cleaning and monitoring of adherence to cleaning. Decolonisation was not recommended
as a routine measure. Although there has been recent evidence of success with mupiricin
for nasal MRSA colonization, logistic difficulties of routine culture and follow-up,
emergence of resistance or recolonisation and lack of efficacy limit the utility
of decolonisation. Overall, these guidelines were not prescriptive, instead giving
general advice and highlighting controversies. They provide a good review of recent
literature evidence and focus on factors that need to be considered when planning
infection control strategy, including MRO, patient and organizational factors.
Application of the pneumonia severity index (PSI) leads
to better use of healthcare resources
Physicians tend to over-estimate the need for inpatient care of pneumonia in otherwise
fit and healthy patients with less severe pneumonia. PSI was introduced to assist
in gauging the level of care required. It has been validated in the past as a good
discriminator for risk of death from pneumonia. This score is used in Australia
and recommended by the Australian antibiotic guidelines to determine the choice
of antibiotic and the decision to manage patients as inpatients or outpatients.
Renaud et al (Clinical Infectious Diseases 2007; 44:41-49) found that the use of the PSI
reduces the proportion of hospital admissions, for those who have low PSI scores,
without increasing mortality. The investigators looked prospectively at PSI-using
hospitals and non-using hospitals. There were 8 EDs in each group and 472 and 453
in the PSI user and non-user hospitals respectively. The PSI user hospitals were
more likely to send low severity cases (PSI risk I or II) home for outpatient treatment.
Postoperative hospital acquired infection is associated
with increased costs of care and with increased utilisation of medical resources.
Loreen et al. (Infect Control Hosp Epidemiol 2006; 27:1291-1298) assessed the effects
of post-operative hospital acquired infection taking into account a number of covariates
(age, NNIS score, severity of underlying illness), hence avoiding the potential
confounding effect of these. Patients in the study had undergone general, cardiothoracic,
or neurological operative procedures and the overall SSI rate at 30 days was 11%.
The findings were that post-operative infection was associated with increased length
of stay, costs and readmission rate, but was not significantly associated with increased
risk of death.
Jodra et al. (Infect Control Hosp Epidemiol 2006; 27: 1299-1303) looked only at
hip SSI and did a case-control study. Findings were that having a hip SSI was associated
with in increase in post-operative stay of 31 days.