Expert Q&A

Pediatric Influenza Vaccination During General Anesthesia

Health care practitioners have used surgery as a “teachable moment,” or an event that encourages their patients to adopt other beneficial health behaviors.

The authors of a recent study1 sought to determine the effectiveness of using general anesthesia as a potential teachable moment for pediatric vaccination against seasonal influenza. After implementing their intervention in children who underwent general anesthesia, the number of influenza vaccinations significantly increased.

To learn more about the study results and their implications, Consultant360 reached out to study author Tyler Morrissey, MD. Dr Morrissey is an assistant professor in the Department of Anesthesiology at the University of Colorado School of Medicine in Aurora, Colorado. He recently presented this research at the American Society of Anesthesiologists 2021 annual meeting.

Consultant360: To begin, could you discuss what prompted this study?

Tyler Morrissey, MD:  Survey data indicates that, prior to the pandemic, Americans get their influenza vaccination most commonly during primary care visits. The decrease in in-person primary care visits during the COVID-19 pandemic has exacerbated already declining rates of routine childhood vaccinations. The pandemic prompted us to think of alternative strategies to promote influenza vaccination in other health care settings. In addition, the American Academy of Pediatrics has released a statement that vaccination should be recommended during all health care seeking opportunities.  

The perioperative setting has historically been a very underutilized setting for vaccination and represents a large opportunity for health care interventions. In the United States, approximately 6 million children younger than 18 years receive general anesthesia each year. Of those children, more than a million are likely to receive general anesthesia around a vaccination age. Administering a vaccine under general anesthesia also provides several benefits, including patient comfort, reduction of delay in care and immunization, and utilization of existing workflows and processes in the health care setting. 

C360: What are the cons of administering vaccinations while a patient undergoes general anesthesia? Are they different for children vs adults?

Dr Morrissey: Hesitancy toward perioperative vaccination is for 2 main reasons. The first is that a reaction to a perioperative vaccine, like fever or malaise, may mimic a postoperative complication. However, during our study, we examined the maximum patient temperature (Tmax) for the first 48 hours after surgery in patients who were admitted to the hospital following their anesthetic, during which they had received the vaccine. We compared that with the Tmax of a similar group of patients who did not receive a vaccine and found no statistically significant difference between the groups. Additionally, no vaccine-related complications were reported through our institution’s Quality and Safety Reporting System during our study.

The second reason is the question of immune response to vaccinations given under anesthesia. The stress associated with surgery has theoretical immunosuppressive effects because of an increase in catecholamine and cortisol levels, which can suppress antibody production, macrophages, and T cells. Anesthetic agents may also have a direct effect on the immune system, which varies by anesthetic class. Pediatric studies evaluating the effects of anesthesia in children suggest a minor, transient effect on T-cell suppression; the duration of which is inversely correlated with age, with little change in immunoglobulin A and G levels. A systematic review of studies evaluating the immunomodulatory effects of anesthesia concluded that these effects are minor and transient (lasting around 48 hours), and based on current evidence, there is no contraindication to the immunization of healthy children scheduled for elective surgery. Therefore, while these data suggest direct effects from anesthesia on the immune system, most agents exert an effect on the innate, with fewer effects on the vaccine-targeted humoral response. For this reason, the American Academy of Pediatrics states there are no contraindications to vaccine administration in the perioperative period.2 

Additionally, there may be some process-related challenges in dispensing vaccinations in the perioperative setting, depending on the institution. We were able to leverage pre-existing processes that were a part of our “Be inFLUential” campaign in order to make this study work.

I think both the pros and cons are similar for adults as well as children.

C360: Do you believe a similar intervention would work effectively on adult patients? Why or why not?

Dr Morrissey:  Absolutely, especially as primary care visits are down. I see no reason why nonvaccinated adults should not be targeted for vaccination in the peri-operative period, although, of course, we think of “needle-phobia” as being more common in our pediatric population.

C360: Are there any remaining knowledge gaps on administering vaccinations to patients under general anesthesia?

Dr Morrissey: A better understanding of the immune response to anesthesia and surgery would be very helpful in order to ensure that our vaccinated patients are truly building a protective immune response. Ideally, we could design a study that would examine antibody titers weeks after vaccination—this study design is challenging because we would have to draw blood from pediatric patients who may otherwise not require a needle poke. This loses the proposed benefit of patient comfort. We are currently undertaking a study looking at this immune response in a sheep model.  

I should also emphasize here that our study was a retrospective cohort study that was conducted at a single academic center, which limits the generalizability to other settings.

C360: In your opinion, would this approach increase vaccination rates if implemented across the United States?

Dr Morrissey: I certainly think this approach would increase vaccination rates across the United States if undertaken nationwide. The degree to which, though, is debatable and likely warrants further study. For example, how many of our patients who we vaccinated in the perioperative setting would have received vaccination elsewhere if not during our visit? We do not know the answer to that yet.

C360: What are some other “teachable moments” that clinicians can implement in their practices, especially when it comes to pediatric influenza?

Dr Morrissey: I mentioned earlier that the American Academy of Pediatrics recommends that vaccination is discussed at “every health care seeking opportunity.” There are likely several health care settings (ie, specialist care, dental care) that represent additional opportunities to discuss and give vaccinations.



  1. Morrissey T, Mandler TN, Yasster M, Strupp KM. General anesthesia is a ‘teachable moment’ for seasonal influenza vaccination in pediatric patients: preliminary results. Talk presented at: American Society of Anesthesiologists annual meeting; October 9-10, 2021; Virtual. Accessed January 27, 2022.
  2. Kimberlin DW, Jackson MA, Long SS. Red book: 2015 report of the Committee of Infectious Diseases. 2015; 30:98.