ABSTRACT
Hearing impaired listeners heavily rely on facial expressions and unfiltered speech signals for a sufficient speech understanding. Due to the current Cov-id-19 pandemic face masks are worn by almost everyone every day. They therefore interfere especially with the communication of hearing impaired listeners. We used a modified audiovisual German matrix sentence test (AV-OLSA) 1 to further evaluate the effect of face masks on speech intelligibility in a cohort of cochlear implant users (CI, n = 15) and a control group of normal hearing listeners (NH, n = 5). Besides “audio-only”, “visual-only” and “audiovisual” conditions, we added modified conditions. These consisted of an audiovisual condition with a simulated mask and an audio signal, which was edited according to the acoustic filter properties of different face masks (surgical and FFP-2). Our preliminary data show a gain of 5.3 dB (CI) and 2.6 dB (NH) in speech reception thresholds at 80 % word recognition (SRT80%) respectively, if a speaker's video is added to an unfiltered audio signal. Different types of face masks (surgical and FFP-2) led to a deterioration in SRT80% in both groups of up to 7.6 dB (CI) and 4.2 dB (NH) when compared to an unfiltered audiovisual condition without a face mask. The acoustic filter properties of the face masks accounted for up to 2.2 dB (CI) and 1.5 dB (NH) of the deterioration in SRT80%. This effect was therefore less distinct compared to the effect of a missing video signal. Face masks complicate the daily communication. These effects are already detectable in a cohort of normal hearing listeners 2 and even more pronounced in hearing impaired listeners, e.g. cochlear implant users.
ABSTRACT
Background : Since December 2019, the coronavirus disease 2019 (Covid-19) is the main health concern around the world. Host immune response to the virus is variable and can induce a dysregulated inflammatory response associated with venous and arterial thrombosis called Covid-19 associated coagulopathy (CAC). During septic shock, inflammatory reaction generates endothelial activation and procoagulant state with microvascular thrombi inducing disseminated intravascular coagulation (DIC). Although CAC and DIC induce altered coagulation and fibrinolytic responses, their clinical outcomes are different. Aims : We investigated and compared coagulopathy between septic shock and critical Covid-19 patients. Methods : Septic shock patients were diagnosed following the Survival Sepsis Campaign guidelines. They were admitted in intensive care unit (ICU) and included in the study within 2 days after admission. Covid-19 patients were admitted in ICU for severe Acute Respiratory Distress Syndrome (ARDS) due to SARS-Cov2 infection and included within 2 days after admission. Patient's plasma was isolated and used to measure circulating biomarkers by ELISA. Results : We observed an increase in vWF and TFPI in both septic and Covid-19 patients compared to controls, highlighting endothelial damage. Interestingly, circulating TF was only elevated in Covid-19 patients. Platelet activation differed between the two cohorts of patients. P-selectin and Trem-like transcript 1 were specifically heightened in septic shock whereas CD40L was only augmented in Covid-19. Coagulation markers were increased in a diseasedependent way, with PAI-1, tPA and D-Dimers higher in septic shock and fibrinogen level, higher in Covid-19. Conclusions : Covid-19 patients had longer length-of-stay with more pronounced respiratory failure. This strong lung disruption overtime induced plasmatic tissue factor release with sustained inflammatory response characterized by sCD40L and fibrinogen secretion. Given the similarities between Covid-19 and septic shock regarding fibrinolysis and coagulation, but not platelet activation, endothelium seems to play a central role in Covid-19 and might explain the differences between CAC and DIC.