Surgery should be delayed for at least seven weeks after a patient tests positive for Coronavirus disease (Covid-19) as patients are more than two-and-a-half times more likely to die after their operations, if the procedure takes place in six weeks following a positive diagnosis, according to a new global study.
The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. SARS-CoV-2 is the virus that causes Covid-19.
Researchers, whose findings were published in Anaesthesia, performed an international, multicentre, prospective cohort study of 140,231 patients undergoing elective or emergency surgery in 116 countries during October 2020.
Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality.
“31 doctors of All India Institute of Medical Sciences (AIIMS), New Delhi, participated in the study, including patients from surgery, paediatric surgery, orthopedics, cardiothoracic surgery, cardiac anesthesia, neurosurgery and neuroanesthesia. For the first time, it gives us evidence about the least amount of time delay in doing surgery that would optimise final outcomes,” said Dr Shilpa Sharma, paediatric surgeon, AIIMS, New Delhi, who is also the lead author from the hospital.
“However, this needs to be balanced by the disease risk to the patient. At AIIMS, we have been doing RTPCR /CBNAAT routinely for screening all surgical patients. Many times these have come positive, and where possible, we have delayed the surgery and waited for the patient to recover,” she added.
Adjusted 30-day mortality in patients who did not have SARS-CoV-2 infection was 1.5%. This was increased in patients operated at 0-2 weeks (4.0%), 3-4 weeks (4.0%), and at 5-6 weeks (3.6%), but not at 7-8 weeks (1.5%) after SARS-CoV-2 diagnosis, according to the study paper.
Patients operated within six weeks of SARS-CoV-2 diagnosis were also at an increased risk of 30-day postoperative pulmonary complications.
These findings were consistent across age groups, differing severity of the patient’s condition, urgency of surgery, and grade of surgery and in sensitivity analyses for elective surgery.
“These risks decreased to baseline in patients who underwent surgery after at least seven weeks or more of SARS-CoV-2 diagnosis. These findings were consistent across both low-risk (age < 70 years..) and high-risk (age ≥ 70 years) sub-groups. Therefore, surgery should be delayed for at least seven weeks following SARS-CoV-2 infection to reduce the risk of postoperative mortality and pulmonary complications,” said researchers in the paper.
“In addition, we have shown that patients who are still symptomatic seven weeks after SARS-CoV-2 infection and undergo surgery, also have an increased mortality rate. As such, these patients may benefit from a further delay until their symptoms resolve,” they added.
According to researchers, this is the first study to provide robust data regarding the optimal timing for surgery following SARS-CoV-2 infection. The researchers also stated in the paper that while cut-offs beyond seven weeks were not formally tested, they are unlikely to offer a significant advantage, since adjusted mortality rates for delay intervals post seven weeks were broadly stable.
“Moreover, overall mortality following a delay of at least seven weeks was similar to mortality in patients who did not have pre-operative SARSCoV-2 infection.
The study holds significance as it offers evidence to support the safe restarting of surgery in the context of a rapidly increasing number of people who have survived SARS-CoV-2 infection.