Exploring Reusability of Disposable Face Masks: Effects of Disinfection Methods on Filtration Efficiency, Breathability, and Fluid Resistance.

To curb the spread of the COVID-19 virus, the use of face masks such as disposable surgical masks and N95 respirators is being encouraged and even enforced in some countries. The widespread use of masks has resulted in global shortages and individuals are reusing them. This calls for proper disinfection of the masks while retaining their protective capability. In this study, the killing efficiency of ultraviolet-C (UV-C) irradiation, dry heat, and steam sterilization against bacteria (Staphylococcus aureus), fungi (Candida albicans), and nonpathogenic virus (Salmonella virus P22) is investigated. UV-C irradiation for 10 min in a commercial UV sterilizer effectively disinfects surgical masks. N95 respirators require dry heat at 100 °C for hours while steam treatment works within 5 min. To address the question on safe reuse of the disinfected masks, their bacteria filtration efficiency, particle filtration efficiency, breathability, and fluid resistance are assessed. These performance factors are unaffected after 5 cycles of steam (10 min per cycle) and 10 cycles of dry heat at 100 °C (40 min per cycle) for N95 respirators, and 10 cycles of UV-C irradiation for surgical masks (10 min per side per cycle). These findings provide insights into formulating the standard procedures for reusing masks without compromising their protective ability.

A Retrospective Study of End-of-life Care Decisions in the Critically Ill in a Surgical Intensive Care Unit.

AIM: Progress in medical care and technology has led to patients with more advanced illnesses being admitted to the Intensive Care Unit (ICU). The practice of approaching end-of-life (EOL) care decisions and limiting care is well documented in Western literature but unknown in Singapore. We performed a retrospective cohort study to describe the practice of EOL care in patients dying in a Singapore surgical ICU (SICU). The surgical critical care population was chosen as it is unique because surgeons are frequently involved in the EOL process. METHODS: All consecutive patients aged 21 and above admitted to the SICU from July 2011 to March 2012, and who passed away in the ICU or within 7 days of discharge from the ICU (to account for transferred patients out of the ICU after end-of life care decisions were made and subsequently passed away) were included in the study. RESULTS: There were 473 SICU admissions during this period, out of which 53 were included with a mean age of 67.2 ± 11.1 years. EOL discussions were held in 81.1% of patients with a median time from admission to first discussion at 1 day (IQR 0-2.75) and a median number of ICU discussion of 1 (IQR 1-2). As most patients lacked decision-making capacity (inability to retain and process information secondary to the underlying disease pathology or sedative use), a surrogate was involved: group decision in 27.9%, child in 25.6% and an unclear family nominated member in 20.9%. 28.3% of patients were managed as for full active with resuscitation, 39.6% nonescalation of care, and 32.1% for withdrawal. The main reasons for conservative management (nonescalation and withdrawal of care) were certain death in 52.3%, medical futility with minimal response to maximal care (27.3%), and the presence of underlying malignancy (18.2%). There was no significant difference between race or religion among patients for active or conservative management. CONCLUSION: 71.7% of patients who passed away in the ICU or within 7 days of discharge from the ICU were managed conservatively. More timely, EOL discussions and better advance care planning may be needed to improve our patient care for patients on conservative management.