The study was led by researchers in the U.K. and included more than 128,000 surgical patients from hospitals spanning 115 countries. Of those, 3.5 percent had a COVID-19 diagnosis.
Overall, the rates of postoperative VTE were: 0.5 percent of of patients without COVID-19; 2.2 percent of those with perioperative COVID-19, or those diagnosed seven days before to 30 days after surgery; 1.6 percent of patients with recent COVID-19, or those diagnosed between one and six weeks before surgery; and 1 percent of patients with previous COVID-19, or those diagnosed seven or more weeks before surgery.
After adjustment for confounding factors, patients with a current infection had a 50 percent higher risk of developing the serious blood clot, while those with a recent infection had a 90 percent increased risk, findings showed.
VTE was also independently associated with a higher death risk within 30 days after surgery: COVID-19 patients without the blood clot had a 7.4 percent risk of death, rising to 40.8 percent when VTE was involved — a more than fivefold jump.
“People undergoing surgery are already at higher risk of VTE than the general public, but we discovered that a current or recent SARS-CoV-2 infection was associated with a greater risk of postoperative VTE,” said Dr. Elizabeth Li, study co-author and general surgery registrar at University Hospital Birmingham in England. “Surgical patients have risk factors for VTE, including immobility, surgical wounds, and systemic inflammation — and the addition of SARS-CoV-2 infection may further increase the risk.”
