Context: With limited global availability of COVID-19 vaccinations, it is important to prioritise patients who will likely have most benefit. This study calculated the benefits of vaccinating patients waiting for elective (planned) surgery. The study found that vaccination could significantly reduce patients’ risk of dying after elective surgery. In addition, vaccinating surgical patients would save more lives per 1000 vaccines than vaccinating the general population (not waiting for surgery), so the study recommends that governments prioritise vaccination for patients planned to undergo surgery.
Aim: To statistically model the benefit of COVID-19 vaccination for patients awaiting planned surgery using rates of post-operative SARS-CoV-2 and death in surgical patients compared with community SARS-CoV-2 infection and deaths rates.
Impact: This evidence can help health services and governments plan and prioritise the most effective use of vaccination resources.
Strategy: The study focused on patients having elective surgery with an overnight stay in hospital, collected in October 2020, before any COVID-19 vaccinations became available. It was based on data for over 56,000 patients (1,667 hospitals, 116 countries).
The patient data was used to compare the death rates in patients who were diagnosed with SARS-CoV-2 infection after surgery with patients who were not diagnosed with SARS-CoV-2. This was used to estimate how many lives could be saved by COVID vaccination among surgical patients compared with how many lives saved by vaccinating the general population (not waiting for surgery).
Results: Although many hospitals have introduced measures such as nasal swab testing and “COVID-free surgical pathways” (you may have seen these on the news described as ‘COVID-cold’, ‘COVID-green’ or ‘COVID-lite’ hospitals) which reduce risk of patients catching COVID-19 infection in hospital, these measures do not completely remove all risk. Some hospitals may not be organised in a way that it is possible to provide these measures.
This study found that globally between 0.6% and 1.6% of patients are diagnosed with COVID-19 infection after elective surgery.
Impact of COVID-19 infection on surgical patients
Patients who are diagnosed with COVID-19 infection after surgery have 4-8 times higher risk of dying compared to similar surgical patients who are not infected.
Benefits of vaccination for surgical patients
Rigorous previous studies have shown that most COVID-19-related deaths can be prevented by COVID-19 vaccination. This study found that surgical patients are at higher risk than the general population of being diagnosed with COVID-19 infection, and if they are infected, they are at higher risk of dying than someone in the community diagnosed with COVID-19 infection. This means that fewer surgical patients need to be vaccinated to save one life, compared to the general population.
In every age group fewer surgical patients need to be vaccinated to save 1 life than matched people in the general population. Patients over 70 years and those undergoing cancer surgery had the greatest benefit of vaccination. Specifically, 1,840 people aged 70 years and over in the general population need to be vaccinated to save one life, but only 351 in patients aged 70 years and over having cancer surgery.
Risks of vaccination
Vaccines are rolled out only after being rigorously tested for safety in order to gain government approvals for use in patients. Different vaccines are in use in different countries but all must first pass these strict safety checks.
What advice is there for patients who are waiting for surgery?
Patients waiting for surgery who have not yet had a COVID vaccine should discuss this with their surgeon. Patients may want to ask the following questions:
- Would I benefit from having my vaccine before my operation?
- What is my risk from COVID-19 infection around the time of surgery?
- Is it possible to delay my surgery long enough for me to have a complete vaccine course?
- Is it possible for me to be vaccinated, and if so, how do I go about this?
- How is my hospital trying to reduce the risk of me becoming infected with COVID-19?
How long before surgery should the vaccine be given?
Although this study did not investigate the best timing for vaccination before surgery, other studies have shown that the risk of COVID-19 infection is reduced from around two weeks after vaccination. We should aim to give the vaccine at least two weeks before the day of surgery, but a longer gap would be preferable.
Which vaccine and how many doses?
This study did not compare different vaccines and currently there is insufficient data to know which vaccines best protect surgical patients, so any of the COVID-19 vaccines may be used. It is preferable to have both doses of a two-dose vaccine prior to surgery but if it is only possible to give one dose within the timespan, this is better than having neither.
Conclusion and Recommendations for Government: Many countries, particularly low- and middle-income countries, will not have easy access to COVID vaccines for several years. While vaccine supplies are limited, most governments are providing vaccination to groups at highest risk of COVID-19 mortality first.
This study suggests that patients waiting for elective surgery should be offered COVID-19 vaccination ahead of other people of the same age and gender in the general population. Provision of vaccinations for all elective surgery patients could save an additional 58,687 lives worldwide over the next year.