CLIN IC A L NE WS
Timing of Operations for COVID-19 Patients Associated With Mortality By MICHAEL VLESSIDES
O
ne of the most ambitious international research efforts ever undertaken has concluded that when it comes to the safety of surgery following SARSCoV-2 infection, timing matters. A prospective cohort study of more than 15,000 collaborators (Anaesthesia 2021 Mar 9. doi.org/ 10.1111/ anae.15458) concluded that patients who underwent surgery within six weeks of their COVID19 diagnosis had a greater risk for death than their counterparts whose surgery was performed at least seven weeks later. “At the time the pandemic was first starting, we performed a cohort study to examine what happens in patients with perioperative COVID-19,” said Dmitri Nepogodiev, MB ChB, the public health registrar at the University of Birmingham, in England (Lancet 2020;396[10243]:2738). “We found a very high mortality rate in patients who developed COVID around the time of surgery—about 24%. “I think that that paper probably changed practice around the world, where physicians were less willing to operate on COVID-positive patients,” he added. “But as the pandemic went on, it became apparent that there would be an increasing number of people who had been positive for COVID, and we can’t put off operating on them forever. So the question became: What is the right timing to wait before operating on these people?” To find the answer, institutions in 116 countries enrolled consecutive patients into the trial, all of whom were undergoing elective
or emergency surgery for any indication. All surgeries took place in October 2020. Patients were classified as having preoperative SARS-CoV-2 infection based on several internationally recognized criteria. The investigators also collected data on the presence or absence of SARSCoV-2 symptoms and whether the symptoms had resolved by the time of surgery. The time from diagnosis of SARS-CoV-2 infection to the day of surgery was categorized as up to two weeks, three to four weeks, five to six weeks, or seven or more weeks. The study’s primary outcome was 30-day postoperative mortality. “We obviously knew we were going to need a large number of patients, because the rate of perioperative SARS-CoV-2 infection was going to be relatively low,” Mr. Nepogodiev said. “So, we worked really hard to engage as many surgeons and anesthesiologists around the world as possible.” In total, 140,231 patients were included from 1,674 hospitals. Of these, 3,127 (2.2%) had a preoperative SARS-CoV-2 diagnosis. The time from SARS-CoV-2 diagnosis to surgery was up to two weeks in 1,138 patients (36.4%), three to four weeks in 461 patients (14.7%), five to six weeks in 326 patients (10.4%), and seven weeks or more in 1,202 patients (38.4%). Most patients were asymptomatic at the time of their surgery.
Proximity to Diagnosis Negatively Affects Mortality The overall 30-day postoperative mor-tality rate was found to be 1.5% (2,151/140,231). Among patients with
SARS-CoV-2, however, those whose surgery was closer to their infection diagnosis fared much worse than those with delayed surgery. The 30-day postoperative mortality rate was 9.1% (104/1,138) in patients whose surgery was within two weeks of their diagnosis, 6.9% (32/461) at three to four weeks, 5.5% (18/326) at five to six weeks, and 2.0% (24/1,202) at seven weeks or more. In contrast, 30-day mortality in patients who did not have a diagnosis of preoperative SARS-CoV-2 infection was 1.4% (1,973/137,104). Logistic regression models were used to calculate adjusted 30-day mortality rates, which proved largely consistent with unadjusted models. “Obviously, you would expect some selection bias of patients,” Mr. Nepogodiev said. “The ones that are operated on closer to the time of their COVID diagnosis are probably sicker and can’t be delayed. But even when you adjust the data, it seems to be robust that patients benefit from waiting seven weeks.” These findings, he added, were consistent across a variety of subgroups, including age, severity of patient’s condition, urgency of surgery and grade of surgery. When the researchers restricted their analyses to patients who had experienced preoperative SARS-CoV-2 infection, those with ongoing COVID-19 symptoms had a higher adjusted 30-day mortality rate than their counterparts whose symptoms had resolved or those who had been asymptomatic. Moreover, after a delay of at least seven weeks following continued on page 12
‘It became apparent that there would be an increasing number of people who had been positive for COVID, and we can’t put off operating on them forever. So … what is the right timing to wait before operating on [these] people?’ —Dmitri Nepogodiev, MB ChB 4
OR Management News • Volume 16 • September 2021
