The prevalence of Sars-CoV-2 in the immediate period prior to national lockdown and widespread changes to medical practice in the healthcare setting is unknown. It is likely, that virus transmission within hospitals was high at a time when adequate personal protective equipment (PPE) was not mandated or simply not feasible due to a lack of supplies. Both patients were deemed ‘routine’ urgent cases and were treated as such in the week prior to implementation of national and regional guidelines to stem viral transmission. The Pan-London Emergency Cardiac Surgery (PLECS) pathway was set up to deliver a regional service for the delivery of urgent and emergency cardiac surgery with a focus on maintaining a COVID-free in-hospital environment . It outlined several measures, including a focus on pre-operative screening and a full theatre operating protocol to protect both staff and patients in our institution.
Our first case highlights some of the rationale behind the many measures that are now currently in place. The decision to operate was initially based on current guidelines which recommend surgical revascularisation in multi-vessel disease in a diabetic patient for best long term outcomes . However, COVID-19 is as yet an unknown disease entity where outcomes in cardiac surgery are unpredictable. Catheter based treatment options were certainly feasible in this case leading to a shorter stay and possibly a better outcome. All patients now referred for surgical treatment currently undergo extensive review to ascertain whether non-surgical options are viable in the first instance, even at the expense of long term outcomes.
Pre-operative COVID-19 testing of patients has now become mandatory in our institution. Our first case did not have a pre-operative COVID-19 swab due to a lack of typical symptoms. Exactly when and where he contracted the virus is difficult to ascertain. He was in regular contact with healthcare professionals due to his dialysis requirements and was an inpatient at our institution at a time where full PPE was not compulsory or deemed required. It is likely that his transmission was iatrogenic given that he developed symptoms at day 7 from his first arrival. The typical incubation period for the virus is between 5 and 10 days . Although this may well have been negative, we also perform CT thorax as part of our pre-operative screening. Recent studies have suggested that CT changes may even precede PCR findings and clinical signs of COVID-19 . This may well have identified early ground-glass changes that were not visible on chest roentgenograms.
Our second case also highlighted the need for aggressive measures to contain intra-hospital spread of the virus. It is almost certain that he contracted the virus whilst at our institution at a time when little to no PPE was used in theatres, in the intensive care unit or on the ward. Although he did warrant urgent inpatient surgery to treat his endocarditis, it is likely that measures put in place now may well have prevented him contracting the virus.
To date, there have been no further mortalities in post-operative cardiac surgical patients secondary to COVID-19 at our institution. This is likely due to the number of measures introduced but also in part due to careful patient selection as well as a significant reduction in surgical volume. The role of cardiac surgery in the presence of COVID-19 is still very unpredictable and further studies on both short term and long term outcomes are warranted.