For a study, the researchers sought to determine if COVID-19 immunization affected postoperative mortality, pulmonary and thrombotic complications, readmissions, and hospital lengths of stay in patients in the United States. Investigators conducted national observational cohort research that included all 1,255 Veterans Affairs facilities in the United States. Patients who had surgery at least 2 weeks after receiving their second dose of the Pfizer BioNTech or Moderna vaccines were compared to propensity score-matched controls. The 30-day mortality and postoperative COVID-19 infection were the primary objectives. Complications of the lungs or thrombosis, readmissions, and lengths of stay in the hospital were the secondary outcomes. A total of 30,681 patients met the criteria for inclusion. There were 3,104 vaccine recipients (1,903 received the Pfizer BioNTech vaccine and 1,201 received the Moderna vaccine) and 7,438 controls after matching. Full COVID-19 vaccination was linked to lower rates of 30-day COVID-19 infection (Incidence Rate Ratio and 95% CI: 0.09 [0.01,0.44]), pulmonary complications (0.54 [0.39, 0.72]), thrombotic complications (0.68 [0.46, 0.99]), and hospital lengths of stay was decreased (0.78 [0.69, 0.89]). Complications were also reduced in vaccinated patients who tested positive for COVID-19 before surgery, but there were too few of them to detect a meaningful difference from controls. COVID-19 immunization was linked to decreased postoperative morbidity rates. The advantage was greatest in people who had never had a COVID-19 infection before surgery.
