SAN FRANCISCO – The opioid overdose crisis in the United States is now plainly evident in intensive care units (ICUs), finds a study of hospitals in 44 states conducted between 2009 and 2015.
During the study period, ICU admissions for opioid overdoses increased by almost half, investigators reported in a session and related press briefing an international conference of the American Thoracic Society. Furthermore, ICU deaths from this cause roughly doubled.
“This means the opioid use epidemic has probably reached a new level of crisis,” said lead investigator Jennifer P. Stevens, MD, an instructor in medicine at Harvard Medical School, and an adult intensive care physician at Beth Israel Deaconess Medical Center, both in Boston. “And this means that in spite of everything that we can do in the ICU – keeping them alive on ventilators, doing life support, doing acute dialysis, doing round-the-clock care, round-the-clock board-certified intensivist care – we are still not able to make a difference in that mortality.”
Dr. Stevens added that any ICU admission for overdose from opioids is a preventable admission. “So if we have an increase in mortality of this population, we have a number of patients who have preventable deaths in our ICU,” she said.
Efforts to track this epidemic on a national level are important, she said, and the U.S. Centers for Disease Control and Prevention has been investigating opioid overdoses in some cities, including Boston, as they would any epidemic.
The factors driving the observed trends could not be determined from the study data, Dr. Stevens said. But state-specific patterns that show, for example, higher baseline rates and greater increases over time in ICU admissions for opioid overdose in Massachusetts and Indiana may be a starting point for investigation.
Certain practices in the ICU may also be inadvertently contributing. “I imagine that a patient who comes in with an opioid overdose can cause harm to themselves in a number of ways, and the things that we try to do to help them might cause harm in other ways as well,” she said. “So in an effort to try to maintain them in a safe, ventilated state, we might give them a ton of sedation that then prolongs their time on the ventilator. That’s sort of a simple example of how the two could intersect to have a multiplicative effect of harm.”
The idea for the study arose because ICU staff anecdotally noticed an uptick in admissions for opioid use disorder. “Not only were we seeing more people coming in, but we were seeing sicker people coming in, and with the associated tragedy that comes with a lot of young people coming in with opioid use disorder,” Dr. Stevens said. “We wanted to see if this was happening nationally... We asked, is this epidemic now reaching the most technologically advanced parts of our health care system?”
The investigators studied hospitals providing data to Vizient (formerly the University HealthSystem Consortium) between 2009 and 2015. The included hospitals – about 200 for each study year – were predominantly urban and university affiliated, but representation of community hospitals increased during the study period.
Ultimately, analyses were based on a total of 28.2 million hospital discharges of patients aged 18 years or older, which included 4.9 million ICU admissions.
Results reported at the meeting showed that 27,325 patients were admitted to the study hospitals’ ICUs with opioid overdose during the study period, as ascertained from billing codes.
Opioid overdose was seen in 45 patients per 10,000 ICU admissions in 2009 but rose to 65 patients per 10,000 ICU admissions in 2015, a 46% increase.
Furthermore, ICU deaths due to opioid overdose rose by 87% during the same time period, and mortality among patients admitted to the unit with overdose rose at a pace of 0.5% per month.
“This is somewhat unusual because a lot of times, when we are admitting more people to our ICUs or examining [a trend] further, mortality actually goes down. This is partly because maybe we are doing more for them and we are taking care of them in an aggressive way. But it’s also because we are admitting less sick people because we are more aware of the issue,” Dr. Stevens said. “And we saw the opposite of this – we saw that the mortality was going up.”
The use of billing data was a specific means but not a sensitive means of identifying opioid overdoses, she noted. Therefore, the observed values are likely underestimates of these outcomes.