Swab test in biological fluids as predictor of COVID-19 transmission risk during surgery: a prospective cross-sectional study from an Italian COVID center

Background The contamination of body fluids by Severe Acute Respiratory Syndrome Coronavirus 2 during surgery is current matter of debate in the scientific literature concerning CoronaVIrus Disease 2019. Surgical guidelines were published during the first wave of the COVID-19 pandemic and recommended to avoid laparoscopic surgery as much as possible, in fear that the chimney effect of high flow intraperitoneal gas escape during, and after, the procedure would increase the risk of viral transmission. Aim The aim of this study was to evaluate the possibility of SARS-CoV-2 transmission during surgery by searching for viral RNA in serial samplings of biological liquids. Methods This is a single center prospective cross-sectional study. We used a real-time reverse transcriptase (RT) polymerase chain reaction (PCR) test to perform swab tests for the qualitative detection of nucleic acid from SARS-CoV-2 in abdominal fluids, during emergency surgery and on the first post-operative day. In the case of thoracic surgery, we performed a swab test of pleural fluids during chest drainage placement as well as on the first post-operative day. Results A total of 20 samples were obtained: 5 from pleural fluids, 13 from peritoneal fluids and two from biliary fluid. All 20 swabs performed from biological fluids resulted negative for SARS-CoV-2 RNA detection. Conclusion To date, there is no scientific evidence of possible contagion by laparoscopic aerosolization of SARS-CoV-2, neither is certain whether the virus is effectively present in biological fluids.