en Reduction of Oxygen Saturation and Increase of Heart Rate in Hospital Workers Wearing Face Mask during Routine Shift عمومى General پژوهشي orginal article <strong><em>Background & Aims</em></strong>: &nbsp;The COVID<span dir="RTL">-</span>19 pandemic forced healthcare workers to use <a name="OLE_LINK24"></a><a name="OLE_LINK13">Personal Protective Equipment</a> (PPE) or at least wear gowns, gloves, and face masks during their working shifts. Previous research reports some problems such as headaches and itching due to the new working conditions. The present study was conducted to determine the possible physiological changes related to wearing face masks, in the current ongoing situation, among healthy hospital workers.<br> <strong><em>Materials & Methods:</em></strong> A questionnaire was administered to hospital personnel requesting them to measure their oxygen saturation level (SpO₂) and heart beats per minute (BPM) <a name="OLE_LINK31"></a><a name="OLE_LINK30">before and after</a> their shifts. They used a pulse oximeter available in their hospital. Eighty-two hospital workers completed their forms, reporting their pre- and <a name="OLE_LINK29"></a><a name="OLE_LINK28">post-SpO₂ and </a>BPM measurements.<br> <strong><em>Results</em></strong>: Statistically, the comparison of data (before and after shifts) indicated a significant decrease in SpO₂(98.68&plusmn;1.56 versus 97.57&plusmn;1.76, p<0.01) and an associated significant increase in BPM (82.86&plusmn;7.21 versus 93.14&plusmn;5.00, p<0.001). <a name="OLE_LINK58"></a><a name="OLE_LINK43"></a><a name="OLE_LINK42">Also, there was no significant difference (p>0.05) between the mentioned responses for those who used N-95 masks (10 persons) and those who used surgical masks (72 persons). </a><br> <strong><em>Conclusion</em></strong><strong>:</strong> Although these changes were all in the reference range for healthy subjects, these fluctuations in the long term can cause physiological and psychological stress among hospital staff during the COVID<span dir="RTL">-</span>19 pandemic. COVID 19, Face masks, Heart beats per minute, Hospital staff, long working shifts, Oxygen saturation level 11 17 http://ijrabms.umsu.ac.ir/browse.php?a_code=A-10-140-1&slc_lang=en&sid=1 Ghollam-Reza Moshtaghi-Kashanian moshtaghikashanian@hotmail.com 10031947532846001071 10031947532846001071 Yes Associate Professor, Biochemistry Department, Qeshm International School of Medicine, affiliated to Islamic Azad University, Qeshm Island, Iran. Navid Moshtaghi-Kashanian n_moshtaghi@sut.ac.ir 10031947532846001072 10031947532846001072 No PhD student, Division of Biomechanics, Department of Medical Engineering, Sahand University of Technology, East Azerbaijan, Tabriz, Iran. Mohammad Hassan nejad M.hasannezhad@mubam.ac.ir 10031947532846001073 10031947532846001073 No Assistant Professor, Biochemistry Department, Bam University of Medical Sciences, Bam, Iran. Nima Moshtaghi-Kashanian nimamks@gmail.com 10031947532846001074 10031947532846001074 No PhD student, English Language Department Islamic Azad University of Karaj, Iran Hanieh Niroomand Oscuii niroomand@sut.ac.ir 10031947532846001075 10031947532846001075 No Associate Professor, Division of Biomechanics, Department of Medical Engineering, Sahand University of Technology, East Azerbaijan, Tabriz, Iran.