Hold the antianaerobics in the ICU whenever possible

Pip-tazo vs. cefepime

In the ACORN (Antibiotic Choice on Renal Outcomes) trial, results of which were reported by this news organization in November 2023, there were no differences in the highest stage of acute kidney injury or death in the first 14 days between piperacillin-tazobactam and cefepime. Remarking on the results, lead investigator Edward T. Qian, MD, MSc from Vanderbilt University in Nashville, Tennessee, said “I think the big takeaway is that you should feel comfortable starting or using pip-tazo for your patients who are coming into the hospital and receiving empiric antibiotics for acute infection.”

But as Dr. Dickson’s group reported more recently in JAMA Internal Medicine, a 15-month pip-tazo shortage allowed the investigators to conduct a natural experiment comparing 90-day outcomes among 7569 patients with sepsis who received vancomycin plus either pip-tazo or cefepime.

They found in an instrumental variable analysis that piperacillin-tazobactam was associated with an absolute increase in mortality at 90 days of 5.0%, and that patients who received this antianaerobic antibiotic had 2.1 fewer organ failure–free days, 1.1 fewer ventilator-free days, and 1.5 fewer vasopressor-free days.

“Our study reveals the potential risks associated with empirical piperacillin-tazobactam in patients with sepsis without a specific indication for antianaerobic therapy. These findings should prompt reconsideration and further study of the widespread use of empirical antianaerobic antibiotics in sepsis,” the investigators concluded.
 

Who gets what?

In the question-and-answer at the end of the session, comoderator Christina Sarah Thornton, MD, PhD, FRCPC from the University of Calgary, Alberta, asked Dr. Dickson whether the question of antianaerobic overuse in the ICU “is a function that we aren’t able yet from a diagnostic perspective to identify the group that may need antianaerobes? Because we often don’t get culture data back in time for a critically ill patient. Do you think there could maybe be a more rapid diagnostic for these patients?”

He replied that “a lot of our problems would be solved if we had really good, reliable rapid diagnostics for infection,” but noted that most of the patients in the study mentioned above did not have indications for antianaerobics.

Asked by this reporter whether Dr. Dickson’s presentation changed her mind about the use of piperacillin-tazobactam in her patients, Dr. Thornton replied “Yes! It did for me.”

She noted that although in Canada respirologists don’t work in intensive care units, “it makes me wonder about just giving pip-tazo to patients that are really sick. It definitely changed my mind.”

The work of Dr. Dickson and colleagues is supported by National Institute of Health and Agency for Healthcare Research and Quality grants. He reported no other relevant disclosures. Dr. Thornton had no relevant disclosures.