Contamination of pulse oximeter probes before and after decontamination in two intensive care units

Background. The internal surfaces of pulse oximeter probes may be overlooked as hot spots for pathogenic microorganisms in an intensive care unit (ICU), thereby contributing to the high incidence of hospital-acquired infections. Objectives. To determine the growth and identification of microorganisms on pulse oximeter probes in the multidisciplinary ICU (MICU) at Charlotte Maxeke Johannesburg Academic Hospital and the burns ICU (BICU) at Chris Hani Baragwanath Academic Hospital, before and after decontamination. Methods. This was a cross-sectional, comparative and contextual study, using purposive sampling. Data were collected from the internal surfaces of 34 pulse oximeter probes in a MICU and BICU. Each pulse oximeter probe was swabbed before and after decontamination. The endemic microorganism profile for the two ICUs was obtained from a laboratory database. Results. Internal surfaces of 31 (91%; 95% confidence interval (CI) 0.76 - 0.98) pulse oximeter probes were contaminated with 9 different pathogenic microorganisms pre decontamination. Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa were endemic to both ICUs, and were the most-frequently isolated microorganisms. Staphylococcus aureus was the most common microorganism endemic to both ICUs, isolated on the internal surfaces of only 2 pulse oximeter probes. Of the internal surfaces of pulse oximeter probes, 6 (18%; 95% CI 0.07 - 0.35) remained contaminated post decontamination, with a microorganism growth reduction of 80% (p=0.0001). Conclusion. The internal surfaces of pulse oximeter probes may serve as hot spots for an array of pathogens with the potential to cause infection and outbreaks in ICUs. Decontamination of the internal surfaces of pulse oximeter probes should be emphasised

Methods of sputum decontamination with emphasis on local tuberculosis laboratories

One of the major goals for the global control of tuberculosis (TB) in humans is the laboratory diagnosis of Mycobacterium tuberculosis the causative agent of TB. This organism is present in sputum specimens which are often contaminated by other fast growing microflora. Therefore; the use of rapid and effective diagnostic methods for optimal detection of Mycobacterium tuberculosis is required through different decontamination methods. This review considers some of the decontamination methods that have been described for the recovery of M. tuberculosis based on published print and electronic articles. Some of these methods have limitations which may make them unsuitable for use in most local laboratories in the developing world; and these include unavailability of essential reagents and materials; cost of acquiring equipment; lack of skilled personnel and undue delay in the time of processing samples. Despite these challenges; there are some methods that have potentials of being adapted for use in clinical mycobacteriology laboratories in developing countries particularly Nigeria. With the correct laboratory logistics put in place; the simplified concentration; Kudoh-Kudoh; and modified Petroff methods may go a long way in achieving effective sputum decontaminations under local setting. The potentials and challenges of using other decontamination methods are discussed