This was a cross-sectional study using data from a prospectively collected database of all patients undergoing surgery and other procedures under general anesthesia in our institution, which is a university-affiliated academic center.
Study participants and eligibility criteria
For our study, we included all pediatric patients aged 18 years and under who had PSS from 18 March 2020 (the start date of lockdown) to 31st May 2020.
Each patient was evaluated for symptoms and risk factors for COVID-19, using a standard checklist which included the following:
-
1.
Presence of COVID-19-related symptoms—fever, cough, sore throat, shortness of breath, coryza, and loss of or reduced sense of smell.
-
2.
High-risk contact in the preceding 14 days.
-
a.
direct contact with anyone confirmed or suspected to have COVID-19;
-
b.
attendance at mass gathering events, eg conferences, places of worship, large weddings;
-
c.
travel from another country or location with confirmed cases of COVID-19.
A patient was categorized as ‘low risk’ when none of the above factors were present and was deemed eligible for inclusion in this study.
When the answer was the affirmative to any of the above items, the patient was categorized as a ‘Person Under Investigation’ and additional precautionary measures were taken to prevent healthcare worker (HCW) transmission. The patient then entered an institutional workflow for suspected COVID-19 cases and was deemed NOT eligible for inclusion in this study.
In patients undergoing emergency surgery, swab results were used to guide post-operative management but confirmed results, either positive or negative, were not required prior to the start of the procedure. For semi-urgent or elective cases, swab results were confirmed prior to the start of surgery.
We used the following definitions to classify acuity of surgery, which were government issued guidelines during the study period:
-
(1)
Emergency—patient’s condition requires surgery within 24 h, without which life is threatened or morbidity is increased.
-
(2)
Semi-emergency—patient’s condition requires surgery within 1 week, without which there is increase in morbidity.
-
(3)
Elective—patient’s condition requires surgery within 1–6 months, without which the patient is affected in development, function, quality of life; or becomes an emergency.
Swab runs were performed by our laboratory twice a day, with results ready within 4 h of the run. All patients were confined to our inpatient wards while waiting for test results and for surgery. There was a blanket ban on visitors, with only a single caregiver allowed to accompany each child while in the ward.
Procedure and protocol for pre-surgical swabbing (PSS)
Once deemed ‘low risk”, patients are brought with a parent to an isolation negative pressure ventilation room for the swab. A designated team of trained medical personnel performs the swab in pairs. They don personal protective equipment (PPE), which consists of fit-tested disposable N95 respirators, face shields, long-sleeved gowns, double-layered gloves, and protective footwear to achieve maximum droplet and contact isolation protection.
During performance of the nasopharyngeal (NP) and oropharyngeal (OP) swabs, the patient must be seated comfortably with the back of the head against a parent’s front of body. The OP swab is performed first in which the swab stick is inserted until it reaches the posterior pharynx between the tonsils. The OP swab is technically easier to perform than the NP. The NP swab is inserted in the nose horizontally, along an imaginary line between the nostril and the ear. The swab is directed toward the wall of the oropharynx and it is rotated about five times before removal. After taking the sample, the swab stick is inserted into a viral contained transport media tube. The specimens are transported in ice in a tEriple layer package to the lab to be processed.
After completion of the swabbing procedure, doffing is followed by complete personal hand hygiene.
Confirmation of COVID-19 is based on detection of unique sequences of viral RNA by real-time reverse transcription polymerase chain reaction (rRT-PCR) with confirmation by nucleic acid sequencing [10].
Follow-up and data analysis
All patients were followed up for 2 weeks post-swab to assess for COVID-19-related symptoms, taking into account an incubation period of up to 14 days.
We performed a descriptive analysis, with data presented as median (range) and proportions described as n (%).