key: cord-0933906-x06dked1
authors: Bobenchik, April M.; Maslow, Andrew D.; Angus, Aimee B.; Murphy, John; Kurtis, Jonathan D.; Chapin, Kimberle C.
title: Testing the asymptomatic pre-surgical population for SARS CoV-2
date: 2020-08-26
journal: J Cardiothorac Vasc Anesth
DOI: 10.1053/j.jvca.2020.08.041
sha: 41a805e3bfc2ac2efe0babe306f8a4058d4b9d63
doc_id: 933906
cord_uid: x06dked1

nan

In response to the COVID-19 pandemic health care facilities deferred all but emergent surgeries for > 12 weeks to minimize/reduce risk to patients and health care workers (1,2,3,4,5,6). However, by April 2020, increased mortality for delaying necessary cardiac and thoracic procedures prompted multidisciplinary teams to determine how to safely restart surgical cases, balancing the urgent needs of patients, the reported increased morbidity and mortality of Covid-positive patients undergoing surgical procedures (2,3,7,8), and risk of spreading Covid-19 infection among health care workers (4,6,7,9,10,11).

Donning of personal protective equipment (PPE) by healthcare workers and screening of patients for Covid-19 infection are necessary for the success of surgery during the pandemic (10,12). Screening includes a questionnaire regarding signs symptoms of Covid-19, exposure to an infected person, SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) testing, with or without thoracic computed tomography (CT) (4,5,10,11,12,13,14,15) . While screening should be universal, PCR testing and CT imaging may not be available or, in low prevalent areas, may not be necessary (10,12). Furthermore, universal PCR testing for health care workers has not been advocated, but only for those with signs, symptoms, and/or exposure

The results of preoperative screening and PCR SARS-CoV-2 testing (Cobas®6800, Roche Diagnostics, Indianapolis, IN. FDA approved March 2020) at our institution are reported during the restart and ramping up of surgical cases.

After approval by the Lifespan Institutional Review Board, 14 weeks of SARS-Cov-2 PCR testing data was collected starting with the restart of elective surgical cases in April 2020.

For comparison, data also included non-surgical patients with suspicion of infection. All had a nasopharyngeal SARS-Cov-2, PCR test (Cobas®6800, Roche Diagnostics, Indianapolis, IN.

FDA approved March 2020) performed, with the surgical group being tested within 72 hrs. of their procedure. Forehead temperatures were assessed, and all patients reviewed and answered a questionnaire regarding possible COVID-19 exposure and related symptoms for the 10 days prior to the test (15). Patients who were afebrile, without symptoms of Covid-19 or exposure were considered asymptomatic.

Following the initial 11 weeks, the medical center policy changed and outpatient surgical patients were screened with a questionnaire and temperature recording. If asymptomatic, afebrile, and without record of exposure to a Covid-19+ or suspected patient for 10 days prior to surgery, then PCR testing was not performed. This 10 day time period is in line with likelihood of developing a Covid 19 infection syndrome after exposure and/or the unlikely recovery of replicant SARS-CoV-2 virus 10 days after presenting with symptoms of Covid-19   (10,15,17,18,19,20) .

Healthcare workers were not routinely tested. Policy relied on personal monitoring and reporting of symptoms, signs, and/or fever, all which are in line with CDC recommendations (14). Healthcare workers donned personal protective equipment during aerosolized generating procedures e.g. intubation (12).

Although the actual perioperative care of surgical patients is not described the general practice care is in line with the principle of enhanced recovery to facilitate extubation, ambulation, pulmonary care, and discharge (9).

Surgical follow-up included phone calls for outpatients and chart review for inpatients.

Reports of infection syndromes among healthcare workers were recorded. Patients and health care workers were not tested or re-tested unless they became symptomatic. The data was analyzed with Fisher's exact test, and the Cochran-Armitage test to assess trends of positive tests over time.

A total of 36,939 patients were tested over 14 weeks. 29,655 presented with symptoms and/or suspicion of coronavirus infection of which 2,081 (7.0%) tested positive (TABLE 1) .

The percent testing positive significantly declined from the first to the last week (15.4% vs 3.3%; p < 0.001), between weeks 3 and 4 (14.1% vs 10.9%; p < 0.01) and between weeks and 7 and 8 (9.0% vs 4.4% p < 0.0001) (FIGURE 1 and 2) . 7,284 consecutive asymptomatic pre-surgical patients were tested during the 14-week period, of which 30 (0.4%) tested positive for SARS-CoV-2 (TABLE 1) . From the first week to the last week there was a significant decline in the percent of positive tests (2.8% vs < 0.5%; p < 0.001) (FIGURE 1 and 2) . In the final 6 weeks, the percent of positive tests ranged between 0.0 and 0.4%. Of the 30 positive patients all were verified as asymptomatic at the time of presurgical screening and all resided in densely populated areas in the state where the prevalence of infection was higher (15). Among these patients there has been no report of an infection syndrome.

After 11 weeks, based on the low number of PCR+ cases and declining prevalence of Recognizing the greater adverse outcome data of Covid-19+ patients undergoing surgery (7,8) and the risk of infection spread from asymptomatic or pre-symptomatic patients Covid-19+ patients (6) preoperative screening has been important to the restart and ramping up of surgical cases (9,10,12). Excellent outcomes continued even after a policy change which shifted from universal to selective PCR testing. Adjustments of the screening algorithm was guided by outcome data, and pre-test probability, the latter based on questionnaire, temperature measurement, and the regional prevalence of the Covid-19 infection (5,10,12,21) .

and among different patient types with greater concern for higher risk patients and procedures.

Questionnaires regarding signs, symptoms, and exposure, and temperature recording are universal (1,9,10,11) . PCR Testing has been recommended before all surgical procedures when possible, but especially cardiothoracic procedures in which lung dysfunction and possible prolonged hospitals stays are anticipated (8,9,10,12,22,23,24,25,26 timing (15,24,25,26,28) . Testing immediately after exposure has a lower sensitivity than 4 days later (5,15) . Two sequential negative tests separated by 3-4 days has a higher sensitivity then a single negative test (15,24,25,26) . One can envision an unlimited number of testing scenarios to reduce the occurrence of false negatives. For cardiothoracic patients many of these scenarios are not practical when considering patient availability, health care resources, delays in surgery, and cost. Others view negative tests cautiously accepted due to the limitations of testing, to the point of treating all patients as if they were Covid 19+ (10,12) .

A practical pre-procedural assessment relying on signs, symptoms and exposure and selective testing can be safely implemented in a region of low prevalence and low pre-test probability (5).

Although a 10 day absence of signs, symptoms, and exposure was chosen (10,15,17,18.19.20) , a more conservative policy might use 14 days (16). For the present time, given the greater morbidity of Covid-19 positive surgical patients, screening will continue to include PCR testing until outcome data determine otherwise.

Adherence to policies and procedures is crucial to the successful restart and ramp up of surgical cases. Guided by outcome data, availability of resources, and determination of pre-test probability, screening procedures and policies can be reassessed and redesigned to improve resource utilization without compromising the patient or increasing the exposure of health care workers to the SARS-CoV-2 virus. Together with health care worker vigilance, continued ramping up of surgical procedures can continue.

None https://www.asahq.org/about-asa/newsroom/news-releases/2020/06/asa-and-apsf-jointstatement-on-perioperative-testing-for-the-covid-19-virus.

Engelman 

Investigation Team: Clinical and Virologic Characteristics of the First 12 Patients with Coronavirus Disease 2019 (COVID-19) in the United States

Virological assessment of hospitalized patients with COVID-2019

Epidemiologic Features and Clinical Course of Patients Infected With SARS-CoV-2 in Singapore

Profile of RT-PCR for SARS-CoV-2: A preliminary study from 56 COVID-19 patients

Rhode Island Department of Health COVID-19 Data Tracker

Preoperative Covid Testing: Examples From Around The