Crib Mattress Investigation: A quality improvement study to assess mattress cover permeability and bacterial growth in crib mattresses

Abstract

Any opening in a medical bed mattress cover may allow bodily fluids to enter the mattress, leading to contamination and potential nosocomial infection. This study's purpose was to assess permeability of crib mattress covers and measure bacterial growth within and on crib mattress surfaces. Mattresses were selected randomly from hospital inventory. Bonney's blue dye was applied over mattress covers to assess permeability. Mattress cover surface swabs were acquired from standardized locations. Samples of mattress foam were acquired under sterile conditions. All samples were collected with the Eswab and eMRSA systems (Copan Diagnostics Inc, Brescia, Italy). Total aerobic bacteria count and colony types were assessed. Results are presented as mean ± standard error of the mean, independent t tests and analysis of variance were used to analyze data, and significance was achieved with P < .05. All mattresses (n = 7) had Bonney's blue dye visible on underlying mattress foam. There were 77 samples and 44 had bacterial growth. Total bacterial count ranged from 0.2-11.6 CFU/cm(2) with mean of 1.7 ± 0.38 CFU/cm(2). There was no relative differences between mattress sample location and colony type. All samples were negative for Staphylococcus aureus, including methicillin-resistant S aureus. Any crack in a mattress cover renders it permeable to fluid entering the mattress. Bacterial growth was present on mattress covers and within mattress foam. Mattresses support microbial viability from which nosocomial infection may occur.