The Face mask and changes in the blood oxygen saturation of theatre workers at the Nnamdi Azikiwe University Teaching Hospital, Nnewi, Anambra State Blood Oxygen changes among theatre users using facemask in Nigeria

Abstract

Background: Facemasks provide some level of protection to theatre workers in case of fluid splash, and has become essential post-COVID. However, wearing facemasks during long procedures may lead to an increase in the level of CO₂ trapped beneath the mask, potentially decreasing the blood oxygen level. Objective: to investigate changes in the oxygen saturation levels of theatre workers at the Nnamdi Azikiwe University Teaching Hospital. Materials and Methods: quasi-experimental study involving healthy theatre workers. Data on demographic details, and medical and social history was collected using a proforma while the temperature and humidity of the theatre were measured, and values of oxygen saturation of each individual were collected using a pulse oximeter. Results: Overall mean SPO₂ of all theatre workers before surgery was 98.05 ± 0.85, which decreased significantly (p<0.05) 2 hours later (96.50+0.14) and then increased again. Significant decrease in SPO₂ level was observed for surgeries lasting 0-60 minutes and 2 hours later for surgeries lasting 121-180 minutes. SPO₂ level of theatre workers decreased significantly between 0.5 hours to 2 hours later in workers using surgical face masks. Conclusion: Changes in SPO₂ of theatre workers in the teaching hospital occur in short-duration surgeries and when the theatre workers have reached their stress threshold, likely between 2 hours and 2.5 hours into the surgery. Furthermore, the decrease in SPO₂ of theatre workers in this tertiary institution only occurs in those that use the surgical type of face mask.