Updated Guidance on Anesthesia with Antithrombotic Therapy

The American Society of Regional Anesthesia and Pain Medicine (ASRA) has updated its evidence-based guidelines on regional anesthesia in patients on antithrombotic or thrombolytic therapy.

The two major changes to the fifth edition are updates to terminology and advice on when to order drug-specific coagulation assays, lead author Sandra Kopp, MD, with Mayo Clinic in Rochester, Minnesota, said during a media briefing.

“With the number of blood thinning medicines increasing dramatically since the first guideline in 1998, doing an update about every 5-7 years has been really important to help keep our patients safe,” Kopp noted.

She also noted that about 6 million people in the United States are taking a direct oral anticoagulant and another 36 million or so are taking antiplatelet medication — and roughly 20% of that 40 million will have a surgical procedure in a year. “That’s a huge number of patients that are impacted by this,” Kopp said.

The updated guidelines were published online on January 29 in Regional Anesthesia & Pain Medicine.

Terminology Tweak

For the fifth edition, the working group reviewed available evidence published since 2018 to provide guidance on “extremely rare”, but “potentially catastrophic” hemorrhagic complications associated with regional anesthesia, particularly neuraxial hematoma.

Estimates are that about 1 in 150,000 epidurals and about 1 in 220,000 spinals can lead to neuraxial hematoma, but it’s “really difficult to know exactly what the risk is, and it’s really hard to study because it’s so incredibly rare,” Kopp said.

Where the evidence is limited, the writing group continues to recommend an “antihemorrhagic approach focused on patient safety” and they propose “conservative times” for the interruption of therapy prior to neural blockade.

In previous editions of the guidelines, anticoagulant doses were described as “prophylactic” and “therapeutic.” The latest edition adopts “low dose” and “high dose” — which is consistent with other published guidelines “and allows us to speak in the same language,” Kopp said.

This terminology also more accurately describes the dose in the setting of specific patient characteristics and indications. For example, the same “high dose” may be used in a patient as a treatment for deep venous thrombosis (DVT) and in another patient as prophylaxis for recurrent DVT, the authors pointed out.

Need for a Drug-Specific Assay?

Kopp noted that drug-specific assays to determine whether a patient remains anticoagulated after they are taken off a specific mediation are becoming easier to access.

Therefore, the updated guidelines offer recommendations around “what the blood test should show and maybe which patients you should actually draw the blood test on. Not every patient needs a blood test if they follow the recommendations,” Kopp said.

When asked whether there are specific anticoagulants that are perhaps safer than others going into surgery, Kopp said “probably not. Each one is going to have a little bit different of a recommendation and following the specific recommendations should allow patients to safely undergo these procedures.”

Raj Gupta, MD, professor of anesthesiology at Vanderbilt University in Nashville, Tennessee and member of the ASRA board of directors, said work is underway to update the “ASRA Coags” app to reflect the fifth edition of the guidelines.

The information is “only useful if the right information is in the hands of the doctors, the surgeons, the anesthesiologists, and the people taking care of these patients,” Gupta told the briefing.

He noted that when the first version of the app was developed in 2014 as part of the third edition of these guidelines, “we realized we really had a hit on our hands because the guidelines are so detailed and there was a need for an easy way to use them.”

This research has no commercial funding. Disclosures for the writing group are available with the original article.