Trends in otolaryngology-head and neck surgery procedural volumes during the COVID-19 pandemic

INTRODUCTION

The novel coronavirus disease (COVID-19) outbreak, caused by severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 (SARS-CoV-19) pandemic significantly impacted healthcare organizations worldwide. Heightened precautions led to decreased elective surgical procedural volumes and hospital visits across all specialties, particularly during the initial months and subsequent surges of the pandemic.^1,2 Guidelines and recommendations from numerous governing medical organizations were published to direct practitioners on providing care during this time.³ The American College of Surgeons (ACS) released guidelines in March, 2020 stating that practitioners should triage their cases provide patient care to individuals with time-sensitive, urgent, and emergent medical conditions only.⁴ With increased data on transmission and infection rates, elective surgical procedures were gradually restarted.

There has been increased concern among returning to pre-pandemic surgical volumes among otolaryngologists due to the most surgical procedures involving the upper aerodigestive tract and a higher chance of COVID-19 transmission. The American Academy of Otolaryngology-Head and Neck Surgery published specific guidelines due to perceived higher risk of exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among otolaryngologists. American Academy of Otolaryngology-Head and Neck Surgery, 2020; Piccirillo, 2020). The guidelines specify factors to stratify risk and urgency of surgical interventions and specifically caution against conducting aerosol-generating procedures.^5,7 Aggregate ENT procedural volumes, compared to those of other specialties, experienced the steepest declines during the initial phases of the pandemic.8 One year after the pandemic, ENT was the only specialty to maintain decreased surgical volumes compared to pre-pandemic volumes.⁸

The COVID-19 TrinetX (Cambridge, MA) database is a rapidly growing global network of electronic medical record (EMR) data with extensive information on over 90 million patients from 67 healthcare organizations (HCOs).⁹ The database provides HIPAA-compliant, de-identified patient information on demographics, medical history, inpatient diagnoses, treatments, laboratory values, and clinical outcomes. Importantly, the COVID-19 TrinetX database provides information on the number of procedures performed. The objectives of this study are to characterize rebounding trends in ENT surgical volumes within two years of the pandemic and to assess trends based on ENT sub-specialty.

METHODS

The data included in this study represents the available data within the TriNetX database COVID-19 research network as of March 15, 2022. Given the publicly available, de-identified nature of the dataset, Institutional Review Board approval was not required.

The Otolaryngology Case Log Coding Guidelines, created by the ACGME Review Committee for Otolaryngology-Head and Neck Surgery, was used to determine the most relevant surgical procedures.¹⁰ The guidelines assist ACGME-accredited otolaryngology programs by setting nationwide benchmarks regarding surgical volume and expertise, ensuring a high standard of surgical training and a degree of uniformity for all otolaryngology residency training programs. The 30 most common otolaryngology procedures and associated Current Procedural Terminology (CPT) from the guidelines were compiled and included for analysis (Table 1).

The database was queried for monthly case volume of inpatient and outpatient ENT-related procedures between February 1, 2018 and January 31, 2022. The timeline was chosen to equally represent two years before the pandemic, assuming the pandemic had global significant impact by February 1st, 2020, and two years after the start of the pandemic. Corresponding number of reporting HCOs, which varied for each procedure and each month, were averaged for each procedure, and compiled for analysis. Monthly CPT-specific procedural volumes per HCO were categorized based on 3-month seasons. Seasonal averages (March to May, June to August, September to November, December to February) were analyzed from February 1st, 2018 to January 31st, 2022. Seasonal averages from 2018 and 2019 were combined to offer an accurate assessment of pre-pandemic volumes. Seasonal averages from 2020 and 2021 were similarly combined to explore the lasting impact of the pandemic. Pre- and post-pandemic seasonal averages were compared on a seasonal basis. Data was recorded and analyzed on Microsoft Excel. Student's t-test was utilized to test for statistical significance and a p<0.05 was considered significant.

RESULTS

A total of 2,005,796 ENT surgical procedures from 45 HCOs from February 1st, 2018 to January 31st, 2022 were analyzed in this study. Months were grouped by season: Spring (March, April, May), Summer (June, July, August), Fall (September, October, November), and Winter (December, January, February). In our analysis, the pre-pandemic time period was from February 1st, 2018 to February 29th, 2020 and the post-pandemic time period was from March 1st, 2020 to January 31st, 2022.

Trends by season

When comparing the average monthly post-pandemic (2020 and 2021) volumes to their pre-pandemic (2018 and 2019) seasonal counterparts, there were statistically significant decreases in the average monthly ENT surgical volumes in all seasons. When compared to average two-year pre-pandemic volumes, average two-year post-pandemic volumes decreased in the Spring (-27%, p=0.0297), Summer (-14%, p<0.0001), Fall (-14%, p=0.001), and Winter (-26%, p=0.006) (Figure 1). When assessing post-pandemic seasonal volumes by individual years, total ENT surgical volumes significantly decreased in all seasons, with the steepest decrease from Winter 2019 to Spring 2020, representing the start of the COVID-19 pandemic (Figure 2). Compared to 2019 seasonal volumes, total ENT surgeries decreased in Spring 2020 (-49%, p=0.017), Summer 2020 (-16%, p=0.044), Fall 2020 (-25%, p=0.0017), Winter 2020 (-25%, p=0.0017), Spring 2021 (-13%, p=0.0174), Summer 2021 (-14%, p=0.0036), and Fall 2021 (-16%, p=0.0249). Statistical analysis could not be conducted on Winter 2021 since data was not available for February 2022.

Trends by specialty

Average monthly post-pandemic surgical volumes (2020 and 2021 seasons) were then compared to pre-pandemic volumes (2018 and 2019 seasons) by otolaryngology specialty to assess individual trends (Figure 3, Figure 4, Table 2). General/endoscopic/rhinology procedures significantly decreased in the Winter, Spring, and Summer of 2020 (-11%, p=0.0358; -37%, p=0.0025; -11%, p=0.0024; respectively). The only significant volume decrease in this sub-specialty in 2021 was in the Winter season (-29%, p=0.0036). Laryngology procedures followed a similar trend, with a significant decrease in Winter, Spring, and Summer of 2020 (-16%, p=0.0099; -56%, p=0.0006; -19%, p=0.0002; respectively) and during the Winter of 2021 (-27%, p=0.0036). Head and Neck surgical volumes significantly decreased in the Winter, Spring, and Summer of 2020 (-11%, p=0.0275; -34%, p=0.0049; -8%, p=0.0135; respectively), and Fall and Winter of 2021 had significantly decreased volumes compared to pre-pandemic volumes (-17%, p=0.0029; and -34%, p=0.0005; respectively). Facial plastics and reconstructive surgery experienced significantly decreased volumes in the Spring and Summer seasons of 2020 (-39%, p=0.002; and -7%, p=0.0093; respectively). In 2021, Winter and fall season demonstrated significant decreases in volume (-34%, p=0.0005; and -17%, p=0.0029; respectively). Contrary to those of other subspecialties, paediatric and otologic procedures experienced significant decreases in all seasons of 2020 and trends were maintained in 2021.

Trends by procedure type

The post-pandemic Spring seasons in this study depicted a decline in 26 of 30 procedures, with 5 showing statistically significant decreases (Table 3). The post-pandemic Summer seasons involved a decrease in 28 of 30 procedures, 12 of which were statistically significant (Table 4). The post-pandemic fall seasons involved a decrease in 26 of 30 procedures, half of which exhibited significant decreases (Table 5). Lastly, the post-pandemic Winter seasons revealed decreases in all 30 of the procedures analyzed, with 9 demonstrating significantly decreased volumes (Table 6).

Some procedures experienced significantly decreased volumes in all post-pandemic seasons, including ‘Surgical Procedures of the Auditory System’, ‘Surgical Procedures on the Pharynx, Adenoids, and Tonsils’, ‘Esophagoscopy, flexible, transoral’, and ‘Surgical Procedures on the Lips’. Two procedures that had significant decreases in 3 of 4 seasons were ‘Bronchoscopy, rigid or flexible’ and ‘Endoscopy Procedures on the Larynx’. The only procedures to exhibit increased volumes compared to pre-pandemic baselines were ‘Intubation, endotracheal, emergency procedure’ and I’ncision Procedures on the Trachea and Bronchi’.

Demographics and comorbidities

The differences in patient demographics and comorbidities between pre-pandemic and post-pandemic cohorts was also examined (Table 7). There were 880,022 individuals who underwent an ENT procedure in the pre-pandemic period and 764,242 individuals who underwent an ENT procedure in the post-pandemic period. The ‘post-pandemic period’ group was slightly older than the ‘pre-pandemic period’ group (48 vs 46.8 years, p<0.0001) but there was no gender difference. The Post-pandemic cohort included a higher prevalence of significant comorbidities, including essential hypertension (38% vs 37%, p<0.0001), type 2 diabetes mellitus (16.9% vs 16.7%, p<0.0001), and tobacco usage (7.8% vs 7.5%, p<0.0001). The same cohort had a lower prevalence of Chronic Obstructive Pulmonary Disease (9.7% vs 10.3%, p<0.0001), long-term steroid usage (6.6% vs 7%, p<0.0001), and history of malignant neoplasm (13% vs 14%, p<0.0001). Rates of obesity were similar between both groups.

DISCUSSION

Using the Trinet X platform, we found that the COVID-19 pandemic significantly decreased the number of Otolaryngology procedures performed. Spring of 2020, which marked the early stage of the pandemic, exhibited the steepest reduction in otolaryngology volumes, decreasing by nearly half compared to the preceding season. The decline in overall volumes mirrored those of other specialties. However, while volumes of other specialties returned to or near baseline, otolaryngology volumes did not. Two years after the onset of the pandemic there has been a gradually increasing trend in volumes in the number of procedures performed, but case volumes are still lower than before the pandemic.

Mehbrabian et al reviewed the TriNetX database to measure pre- and post-pandemic trends in plastic and reconstructive surgical volumes. Decreasing trends were observed for most procedures, but volumes rebounded within 1 year of the pandemic.² When analyzing surgical volume trends during the first post-pandemic year, Mattingly et al observed that Otolaryngology and musculoskeletal procedures experienced the steepest decrease in the first year of the pandemic compared to other procedural volumes.⁸ They further observed that by the time of the COVID-19 surges in the Fall and Winter of 2020, surgical volumes across all specialties returned to pre-pandemic baselines except for otolaryngology.⁸ Our study found that otolaryngology volumes trended upwards in 2021, suggesting potential return to pre-pandemic baselines. The trends were observed when ENT volumes were analyzed based on surgical subspecialty, including General/Endoscopy/Rhinology, Laryngology, Head and Neck Surgery, and Facial Plastics and Reconstructive Surgery.

While otolaryngology emergencies are common, many frequently performed procedures are elective._11–13 Guidelines advising against performing elective surgeries significantly impacted surgical volumes, perhaps more so than other fields. In addition, some otolaryngologists may have been more cautious in performing surgical interventions due to their direct involvement with the airway. Aerosol-generating procedures were likely minimized or avoided due to increased risk of contracting SARS CoV-2 given its respiratory droplet-mediated transmission.¹⁴ Cheng et al found that Otolaryngologists had higher rates of COVID-19 infection than physicians in other specialties.¹⁵

Pediatric otolaryngology and Otology were the only subspecialties that did not exhibit rebounding volumes. Given children’s lower risk of developing severe COVID-19 compared to adults, rebounding volumes would be expected, but were not observed.¹⁶ The most common pediatric otolaryngology procedures include adenoidectomies, tonsillectomies, and myringotomies with tympanostomies.^17,18 Since these procedures are largely elective, parents may have been less likely to seek care and surgical intervention. Decreasing pediatric otolaryngology procedures may have also been impacted by social changes induced by the pandemic, including remote learning.¹⁹ Limited interaction with other children in school or daycare may have reduced transmission of upper respiratory infections, thereby decreasing incidence of recurrent tonsillitis, pharyngitis, and acute otitis media. Otology procedures similarly did not return to pre-pandemic baselines. Patients may have been hesitant to seek medical care for common otology procedures, such as cerumen removal, opting for over-the-counter treatments instead. The trend in Otology procedures may have been impacted by an overlap with pediatric procedures, as tympanostomies with myringotomies were categorized as Otology procedures due to database query limitations.

Only two otolaryngology procedures increased during the post-pandemic period: emergency endotracheal intubation and incision procedures of the trachea. This is unsurprising due to the increased risk of intubation among patients with COVID-19.^20,21 Interestingly, the pre-pandemic cohort had a greater prevalence of COPD, which can contribute to severity of illness presentation and deferral in care to avoid risk of intubation. The pre-pandemic and post-pandemic cohorts differed significantly, as the post-pandemic population was older and had more medical comorbidities than the pre-pandemic cohort. The post-pandemic cohort likely required more urgent medical care than the pre-pandemic cohort, who were more likely to defer medical care.

There were several limitations to this retrospective study. Among the 67 HCOs included in the TrinetX database at the time of query, there was heterogeneity in the number of HCOs which reported CPT codes, as demonstrated in Table 1, introducing a potential information bias. HCOs were located internationally, and varying regulations among countries may have impacted surgical volumes. Otology procedures could not be practically stratified to differentiate pediatric otolaryngology cases from procedures performed on adults, which may have skewed the data on Otology procedural volumes. Finally, due to the retrospective study design, confounding variables could not be controlled due to a lack of availability of clinically relevant patient information.

CONCLUSION

Overall otolaryngology surgical volumes decreased in the two years since the start of the COVID-19 pandemic. However, rebounding trends have been shown in several of the otolaryngology subspecialties, though none have yet maintained or surpassed pre-pandemic baselines. Interestingly, pediatric and otologic sub-specialties seem to have suffered the most significant decrease in case volumes in this dataset.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: The study was approved by the Institutional Ethics Committee

REFERENCES

1. 1. Saraswathula A, Gourin CG, Stewart CM. National Trends in US Otolaryngology Surgical Volume during the Early COVID-19 Pandemic. JAMA Otolaryngol Head Neck Surg. 2021;147(4):397-9.
2. 2. Mehrabian D, Liu IZ, Pakhchanian HH, Tarawneh OH, Raiker R, Boyd CJ. Nationwide analysis of plastic and reconstructive procedural volume in the United States during the COVID-19 pandemic. Journal of Plastic, Reconstructive and Aesthetic Surgery. 2022;75(4):1483-96.
3. 3. Centers for Medicare and Medicaid Services. Non-Emergent, Elective Medical Services, and Treatment Recommendations; 2020. Available at: https://www.cdc.gov/coronavirus/2019-ncov/healthcare-facilities/index.html. Accessed on 20 September 2022.
4. 4. American College of Surgeons. COVID 19: Elective Case Triage Guidelines for Surgical Care.; 2020. Available at: https://www.facs.org/media/augjopp0/guidance_for_triage_of_nonemergent_surgical_procedures_otolaryngology.pdf. Accessed 5 July 2022.
5. 5. American Academy of Otolaryngology - Head and Neck Surgery. Guidance for Return to Practice for Otolaryngology-Head and Neck Surgery.; 2020. Available at: https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/burn-calculator.html. Accessed 5 July 2022.
6. 6. Piccirillo JF. Otolaryngology-Head and Neck Surgery and COVID-19. The Journal of the American Medical Association. 2020;324(12):1145-6.
7. 7. Mick P, Murphy R. Aerosol-generating otolaryngology procedures and the need for enhanced PPE during the COVID-19 pandemic: A literature review. Journal of Otolaryngology - Head and Neck Surgery. 2020;49(1).
8. 8. Mattingly AS, Rose L, Eddington HS. Trends in US Surgical Procedures and Health Care System Response to Policies Curtailing Elective Surgical Operations during the COVID-19 Pandemic. JAMA Netw Open. 2021;4(12).
9. 9. TriNetX LLC. TriNetX. Available at: https://trinetx.com/. Accessed on 20 September 2022.
10. 10. ACGME Review Committee for Otolaryngology - Head and Neck Surgery. Otolaryngology Case Log Coding Guidelines. Available at: https://www.acgme.org/specialties/otolaryngology---head-and-neck-surgery/documents-and-resources/. Accessed on 20 September 2022.
11. 11. Adedeji TO, Sogebi OA, Tobih JE. Pattern of Otorhinolaryngological Admissions via Emergency Unit in a Suburban Tertiary Center. Int J Biomed Sci. 2015;11(3):146-51.
12. 12. Crosby DL, Sharma A. Insights on Otolaryngology Residency Training during the COVID-19 Pandemic. Otolaryngology - Head and Neck Surgery (United States). 2020;163(1):38-41.
13. 13. Raj A, Wadhwa V, Jain A. Epidemiological Profile of ENT Emergencies: Our Experience. Indian Journal of Otolaryngology and Head and Neck Surgery. 2019;71:301-4.
14. 14. Wilson AM, Sleeth DK, Schaefer C, Jones RM. Transmission of Respiratory Viral Diseases to Health Care Workers: COVID-19 as an Example. Annu Rev Public Health. 2022;43:311-30.
15. 15. Cheng X, Liu J, Li N. Otolaryngology Providers Must Be Alert for Patients with Mild and Asymptomatic COVID-19. Otolaryngology-Head and Neck Surgery (United States). 2020;162(6):809-10.
16. 16. Zimmermann P, Curtis N. Why is COVID-19 less severe in children? A review of the proposed mechanisms underlying the age-related difference in severity of SARS-CoV-2 infections. Arch Dis Child. 2021;106(5):429-39.
17. 17. Bann DV, Patel VA, Saadi R. Best Practice Recommendations for Pediatric Otolaryngology during the COVID-19 Pandemic. Otolaryngology - Head and Neck Surgery (United States). 2020;162(6):783-94.
18. 18. Pizzuto MP, Volk MS, Kingston LM. Common Topics in Pediatric Otolaryngology. Pediatr Clin North Am. 1998;45(4):973-91.
19. 19. Lessler J, Grabowski MK, Grantz KH. Household COVID-19 risk and in-person schooling. Science (1979). 2021;372(6546):1092-7.
20. 20. D’Amore J, Meigher S, Patterson E. Intubation outcomes and practice trends during the initial New York SARS‐COV‐19 surge at an academic, level 1 trauma, urban emergency department. J Am Coll Emerg Physicians Open. 2021;2(6).
21. 21. Luo M, Cao S, Wei L. Intubation, mortality, and risk factors in critically ill Covid-19 patients: A pilot study. J Clin Anesth. 2020;67.