DISCUSSION
The accuracy of the COVID-19 diagnostic tests is still suboptimal, with
a high percentage of false negatives on the PCR-RNA analysis from
nasopharyngeal swab samples [9]. Also, there are cases where the
individuals with a previous negative test, become positive again in
subsequent tests without any associated clinical deterioration that
would help in predicting this [10].
The ideal convalescence period after having tested positive for COVID-19
it is also unknown, especially in the absence of symptoms or
abnormalities in the chest imaging modalities.
We know from previous reports out of China [3, 4] and our own
experience, that patients who develop COVID-19 during the immediate
postoperative period, regardless of the nature of the surgical
procedure, have a bad prognosis, with high mortality and morbidity
related to respiratory complications.
In the current era, when all the elective surgical procedures have been
paused to prioritise intensive care resources to accommodate the
COVID-19 patients, we have concentrated in treating urgent and emergency
cardiac and aortic surgery cases. We have established a rigorous
COVID-19 screening protocol following international recommendations,
including the combination of questionnaire for COVID-19-related
symptoms, two negative nasopharyngeal swabs, clear lung fields on a
non-contrasted CT chest and the absence of lymphopenia or excessively
elevated LDH levels [5].
In emergency cases there is no option to wait for the swab results,
hence the surgical indication outweighs the risk of COVID-19 infection
especially in the patients with no COVID-19-related symptoms and
pulmonary infiltrates on the CT chest.
However, in the urgent cases, with at least 24 - 48 hours margin to wait
for the screening results, we are now facing a proportion of patients
who are COVID-19 positive with mild symptoms or even not symptomatic at
all. Despite that, all patients are treated as if they were positive and
all the universal PPE precautions taken [5].
To date there is little knowledge of the predictors to determine the
earliest safe time to plan an operation, in patients who may still be
infectious and/or with potential for reactivation in the immediate
postoperative period, with potential catastrophic consequences for their
respiratory system after having been exposed to the cardiopulmonary
bypass with the subsequent systemic inflammatory response.
For this reason, we believe it is important to manage each case
individually, and when time permitting, to wait until the viral load and
the radiological infiltrates (if any) have resolved.
In our experience, the close monitoring in a hospital environment, where
the patients were kept in isolation and only interacting with full-PPE
equipped healthcare professionals, allowed us to postpone the urgent
surgery until they became COVID-19 negative. With those measures in
place, we achieved a good outcome for all of them, without any
COVID-19-related complications in the postoperative period and a 100%
survival rate.
Further studies on a larger volume of patients, like the CovidSurg
international multicentre study, will help to increase to understand the
impact of COVID-19 during the peri-operative period and add some clarity
and recommendations to the optimal timing for offering surgery in
patients recovered from COVID-19.