Mechanical ventilation more frequently used in US than England, Canada

Jivraj NK, et al. JAMA Intern Med. 2023;doi:10.1001/jamainternmed.2023.2371.

Jivraj NK, et al. JAMA Intern Med. 2023;doi:10.1001/jamainternmed.2023.2371.

Use of invasive mechanical ventilation in 2018 was more prevalent in the United States compared with England and Canada, according to study results published in JAMA Internal Medicine.

“Over the past 3 years, demands on health systems worldwide from COVID-19 created an urgent need to have an accurate understanding of available resources and how they are used,” Naheed K. Jivraj, MBBS, MSc, FRCPC, anesthesiologist in the department of anesthesiology and pain medicine at University of Toronto, told Healio. “Early in the pandemic there was significant concern about the availability of ventilators and equity of access to them. However, while many studies as well as the mainstream media were able to report differences in ICU bed availability between countries, there were no population-level estimates or comparisons of mechanical ventilation use. We wanted to look into this to get an accurate understanding of use of this scarce resource and what might be driving differences between countries.”

In a population-based cohort study, Jivraj and colleagues analyzed 1,614,768 (median age, 65 years; 57% men) hospital admissions requiring invasive mechanical ventilation (IMV) in the U.S., 70,250 (median age, 65 years; 64% men) in Canada and 59,873 (median age, 61 years; 59% men) in England from 2018 to compare age-standardized IMV rates and ICU admission rates between countries.

Researchers also divided admissions based on patients’ age, comorbidities and diagnosis to see how IMV rates differed in these subgroups across the selected countries.

Among the three countries, the U.S. had the highest age-standardized rate of IMV with 614 patients (95% CI, 614-615) per 100,000 population, followed by Canada with 290 patients (95% CI, 288-292) and England with 131 patients (95% CI, 130-132).

The U.S. continued to be on top when researchers only looked at patients on IMV who went to the ICU, with 520 patients (95% CI, 520-521) per 100,000 population vs. Canada’s rate of 278 patients (95% CI, 276-280) per 100,000 population and England’s rate of 131 patients (95% CI, 130-132) per 100,000 population.

When evaluating crude IMV rates based on age groups, researchers observed comparable numbers between countries for younger patients but varying numbers for those aged 80 years or older, which Jivraj told Healio was surprising.

More older patients received IMV in the U.S. (1,788 patients per 100,000) than in Canada (694 patients per 100,000) and England (209 patients per 100,000). Notably, up until the 80-year mark, researchers observed heightened IMV rates in the three countries with each rising decade.

Further, researchers found that the U.S. had greater rates of patients with dementia on IMV (6.3% vs. England, 1.4% vs. Canada, 1.3%) and patients dependent on dialysis before ventilation (5.6% vs. England, 1.3% vs. Canada, 0.3%).

In terms of diagnoses at hospitalization, acute myocardial infarction was more frequently found in the U.S. cohort (150 per 1,000 hospitalizations) vs. in England and Canada (each 40 per 1,000 hospitalizations).

Researchers also observed higher admission rates of patients with a pulmonary embolism in the U.S. and Canada (U.S., 40 vs. Canada, 39 vs. England, 8 per 1,000 hospitalizations), as well as patients with gastrointestinal bleeding (U.S., 39 vs. Canada, 25 vs. England, 16 per 1,000 hospitalizations).

“The next step is to develop projects that will focus on identifying patient-, clinician- and system-level factors that might drive differences in rates of mechanical ventilation between countries to ultimately identify best practices,” Jivraj told Healio.

Reviewing these findings, Jivraj said one takeaway for the general public is the question of whether higher rates of intensive care result in better patient outcomes.

“While there is significant variability in use and likelihood of being placed on a mechanical ventilator between countries, it is unclear whether more ‘intensive care’ is better,” Jivraj said. “Despite having more ICU beds and a high rate of mechanical ventilation, the U.S. has a lower life expectancy, ranks lower on international comparisons and had a higher mortality rate from COVID-19. On the other hand, England had the lowest rates of mechanical ventilation, and almost always outranks Canada and the United States in international comparisons of health systems, such as in the Commonwealth Fund Report.”

Another question that arises from this study is who has greater benefits with IMV, Jivraj added.

“One of the largest drivers in differences between countries was age,” he said. “With an aging population, we need more research to understand which older adults stand to benefit the most from mechanical ventilation to ensure they receive equitable access to this scarce resource. Nevertheless, families and their health care providers need to communicate to understand the goals and wishes of older adults near the end of life before delivering or denying therapies such as mechanical ventilation.”

Naheed K. Jivraj, MBBS, MSc, FRCPC, can be reached at [email protected].