Twenty oral morphine equivalents is the best option for pain relief medication with which to discharge outpatients after thyroidectomy or parathyroidectomy surgery, according to researchers. The report was published online in Annals of Surgical Oncology.

Irene Lou, MD, of the department of surgery at the University of Wisconsin–Madison, and her coauthors conducted a prospective observational cohort study collecting data on pain scores and the oral morphine equivalents used by 313 adult patients undergoing thyroidectomy or parathyroidectomy at two large endocrine surgery centers.

While patients were prescribed a median of 30 oral morphine equivalents at discharge – with a range from 0 to 120 – the median number of equivalents taken was 3 (with a range of 0-60).

Overall, 68.4% of patients took at least one oral morphine equivalent. The majority of patients (83%) took 10 or fewer oral morphine equivalents, and only 7% of patients took more than 20 oral morphine equivalents ( Ann Surg Oncol. 2017 Feb 3. doi: 10.1245/s10434-017-5781-y ).

Among the patients who took more than 10 oral morphine equivalents, 85% said it was for incisional pain, 4% said it was for sore throat, and 11% said it was for some other pain.

While the overall mean pain score after surgery was 2, the study found that mean pain scores in the patients who took more than 10 oral morphine equivalents were significantly higher than in patients who took 10 or fewer. Among patients who used narcotic pain relief, 1% said they did so because they were instructed to despite having reported no pain.

Other factors predicting higher oral morphine equivalent use were age – patients tended to be younger than 45 years – total thyroidectomy, or a history of previous narcotic use.

“Based on our results, we have changed our practices to discharge all patients undergoing parathyroid or thyroid surgery and to request an oral narcotic prescription with no more than 20 equivalents, which translates to 20 tablets of hydrocodone/acetaminophen 5/325” the authors wrote.

Noting that the abuse and misuse of prescription opioids is the leading cause of overdose deaths in the United States, they argued that standardized prescribing practices are a way to not only reduce waste but also to improve patient safety.

“We also discovered that even between our two institutions, there was no standard prescribing pattern, with a wide range of prescriptions and number of equivalents dispensed.”

The authors also examined alternative and adjunctive methods of pain relief, pointing to previous studies suggesting benefits from preoperative gabapentin, postoperative music therapy, postoperative ice packs, and nonopioid analgesics.

They noted that because their study covered the breadth of endocrine neck operations, it did include patients who had minimally invasive surgery through to those who underwent total thyroidectomy with neck dissections. They also pointed out that the data pain scores and oral morphine equivalent use was based on patient recollection.

“Notwithstanding these limitations, our study is the first to examine outpatient narcotic pain medication use after thyroid and parathyroid surgery,” they said. “A standardized practice of prescribing stands to increase patient safety and minimize the risks of dependence and overdose.”

Two authors were supported by National Institutes of Health grants. No other conflicts of interest were declared.