2.1 Standard precautions
Four studies report their experience of endonasal surgery during COVID-19 with cumulative patient number of 305.12,25-27 Risk is mitigated through a combination of pre-operative patient testing (with or without detail of subsequent self-isolation for patients) and staff PPE use in the operating theatre, with no added precautions unique to endonasal surgery. Though there were subtle differences between each, all can be considered to reflect variation in standard operating procedure between institutions. None make specific measurements as to aerosolisation but patient and/or staff infection levels are reported as an outcome of risk mitigation. Naik et al. (2020)25 and the work from the CRANIAL Consortium (2021)26 report no symptomatic COVID-19 infections in patients at 14 and 30 days postoperatively, though no formal testing was performed. Penner et al. (2020)12 and Taha et al. (2020)27 tested staff and found no evidence of COVID-19 infection during their case series. Taken as a whole, results suggest that preoperative patient screening, to ensure patients are COVID-19-negative, and PPE use is successful in mitigating risk, though limitations apparent in these case series include lack of description as to local level of endemic infection and so relative risk at each institution, consistency in testing of patients and staff across studies and possible unreported asymptomatic infections.