Risk stratification for emergency operations helps conserve PPE during COVID-19 outbreak

Researchers from the United Christian Hospital and Tseung Kwan O Hospital have developed a risk stratification protocol to guide timely assessments and decisions on the need for emergency surgeries, and to provide a clear framework for the appropriate use of personal protective equipment (PPE) in managing emergency surgical conditions during the coronavirus disease 2019 (COVID-19) outbreak.

Following the implementation of the risk stratification protocol, there was a significant reduction in the proportion of high-risk cases requiring full sets of PPE (p=0.017), with a total of 72 full sets of PPE conserved in 1–7 March 2020. [Hong Kong Med J 2020, doi: 10.12809/hkmj208533]

Compared with the period prior to implementation of the protocol (ie, 2–8 February 2020), 29 percent vs 8.5 percent of patients were identified as high-risk, of whom 14 percent vs 80 percent underwent operation in an isolation operation room, with 16 vs 32 full sets of PPE consumed by healthcare workers (HCWs).

All patients in the study tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on polymerase chain reaction (PCR), and none of the HCWs were infected with SARS-CoV-2.

In the study, patients (n=59 prior and n=49 after protocol implementation) with emergency conditions requiring operations by general surgery, obstetrics and gynaecology, ophthalmology, orthopaedics and otorhinolaryngology departments were first screened for FTOCC (ie, fever, travel history to areas with active community transmission of COVID-19 in ≤2 weeks prior to presentation, occupation exposure, contact and clustering history). Those who screened positive for FTOCC were further assessed for presence of upper respiratory symptoms.

Patients were transferred to isolation or surveillance rooms via the accident & emergency department if they were deemed to be at high risk of SARS-CoV-2 infection with positive screening results for FTOCC ± presence of upper respiratory tract symptoms.

Samples of nasopharyngeal swabs and throat swabs were collected from patients transferred to isolation or surveillance rooms to test for SARS-CoV-2 via COVID-19 rapid PCR prior to their operations.

Eight full sets of PPE (ie, two for anaesthetist, one for operation room assistant, two for runner nurses, one for scrub nurse, two for surgeons) and an airborne isolation room with negative pressure were required for every patient with positive PCR results or overriding emergency surgical conditions (ie, within 4 hours prior to return of test results).

For those with negative PCR test results, standard operating operation procedures with usual precaution ± transmission-based precautions were adopted for surgical operations. These included the use of surgical gown, sterile gloves, and standard surgical mask and cap for all members of the team, as well as two full sets of PPE for the anaesthetist and operation room assistant, if required.

Apart from respiratory droplets and physical contact, SARS-CoV-2 can also be transmitted via aerosol generating procedures (AGPs). The use of PPE including N95 respirator, face shield or goggles, disposable gloves, and splash-resistant gown (ie, full PPE) during AGPs has been recommended by the US CDC and the European Centre for Disease Prevention and Control (ECDC) for effective protection of HCWs against SARS-CoV-2. [https://www.cdc.gov/coronavirus/2019-ncov/infection-control/control-recommendations.html; https://www.ecdc.europa.eu/sites/default/files/documents/COVID-19-infectionprevention-and-control-healthcare-settings-march-2020]

Amid the global pandemic of COVID-19 and the shortage of PPE supply, appropriate use of PPE is crucial, the authors noted.