Intravenous (IV) acetaminophen does not meaningfully decrease opioid use following colorectal procedures, especially compared with oral acetaminophen, according to a study published in Anesthesiology.
“With any new drug that is introduced to the US market, it is very important to monitor how it is used and if this results in the desired outcomes,” said Jashvant Poeran, MD, Icahn School of Medicine at Mount Sinai, New York, New York. “Our study results do not support routine use of IV acetaminophen.”
The researchers explored this topic because there is increasing pressure to reduce opioid use in patients hospitalised for surgery, while also minimising pain. Non-opioid pain medications such as IV acetaminophen are a common substitute for opioids, but it was unclear how effective this drug was for surgery patients.
For the study, the researchers analysed data from 181,640 patients undergoing open colectomy surgery at 602 hospitals across the United States from 2011 to 2016. Oral and intravenous acetaminophen use was categorised separately as ≥1 (1,000 mg) dose on the day of surgery, postoperative day 1, or later.
Among the patients studied, researchers found that IV acetaminophen was used in 25.1% of cases, 48% of which received only 1 dose on the day of surgery. In these patients, IV acetaminophen use was not associated with clinically significant reductions in opioid utilisation.
However, while >1 dose of IV acetaminophen on postoperative day 1 was associated with a -12.4% change in opioid utilisation, patients receiving >1 oral acetaminophen dose had a -22.6% reduction.
The differences were less pronounced between IV and oral acetaminophen in patients who received >1 dose on the day of surgery, with a -8% versus -8.7% reduction in opioid use, respectively.
These results suggest that IV acetaminophen is not always used appropriately, as 1 dose may not be enough to affect opioid utilisation. Researchers say there may be a place for IV acetaminophen among patients who cannot tolerate oral medication, but follow-up studies should be done to figure out what the most effective dosing regimen is.
“It is important that we that we identify optimal dosing strategies and patients that are most likely to benefit from this relatively new drug,” said Dr. Poeran. “Especially among patients undergoing colorectal surgery, there may be a group of patients that do not tolerate oral medications. This may be less of an issue among patients undergoing other types of surgery, such as hip and knee replacement surgery, and these results further emphasise a more targeted approach in determining who benefits most.”
“A wide variety of non-opioid adjuvants are available for use, but our knowledge of what works best in whom is still in its infancy,” added Andrew Leibowitz, MD, Icahn School of Medicine at Mount Sinai.
The researchers are currently addressing this same question in other types of surgery, such as hip, knee, and shoulder replacement, and anticipate more findings in the near future.