Doctors and researchers at Middlemore and Whangarei Hospital also found the quantity of opioids prescribed at discharge was independently associated with a 30 per cent increase in opioid consumption.

The research, an international, multicentre, prospective cohort study of general surgical, urological, gynaecological, and orthopaedic surgery with a seven-day post-discharge phone call follow-up was performed by Trials and Audits in Surgery by medical students in Aotearoa New Zealand and Australia (TASMAN) Collaborative.

Key findings:  

4,273 patients were recruited from 144 hospital centres across 25 countries.
Median age 50.
53.1 per cent female / 46.9 per cent male.
Patients underwent 19 very common surgeries.
At discharge, 1,311 (30.7 per cent) were prescribed an opioid pain killer, and a median 100 milligrams or 10 tablets of 10 mg sevredol.
Seven days after surgery, a median of only 40 milligrams (4 tablets of 10 mg sevredol) had been consumed.
Further analysis showed having opioids did not improve patients’ pain when they were at home or satisfaction, but did increase the risk of representation to medical services for opioid side effects.

Dr Chris Varghese, an Honorary Lecturer at the University of Auckland and Junior Doctor at Middlemore Hospital in Auckland said after accounting for patient factors, including pain, the surgery type, and patient comorbidities, the quantity of opioids prescribed at discharge was independently associated with increased use of opioids.

“The inappropriate over-prescribing of opioids after surgery is contributing to the global opioid-crisis,” Dr Varghese said. 

“Our international cohort study aims to identify factors that drive increased opioid consumption at seven-days after discharge from common surgical procedures.  

“Generally, surgeons prescribe double the number of opioids a patient consumes in the first week after surgery.

“The more opioids we prescribe, the more a patient uses at home, and this is not explained by differences in pain levels. 

“We also found prescribing more opioids did not improve the experience of pain or satisfaction with pain relief given, but did increase risk of side effects.

“We send patients home with too many opioids after surgery. The over-prescription of opioids is not a problem isolated to the United States, it’s an issue in Aotearoa New Zealand too. 

“We need to better tailor opioid prescriptions to individual patients, there is no one size fits all answer.

“This research offers doctors and patients real-world data to guide when an opioid is needed, and if an opioid is being prescribed, how much opioid is typically used by patients. The data will help us think more carefully about our pain relief prescriptions so it’s tailored to patients’ needs.”

The TASMAN Collaborative’s research will be unveiled at the the Royal Australasian College of Surgeons Annual Scientific Congress in Adelaide (1-5 May).

The Congress is the largest multi-disciplinary surgical meeting held in the southern hemisphere and brings together some of the top surgical and medical minds from across Aotearoa New Zealand, Australia, and the rest of the world.

For more information about the Royal Australasian College of Surgeons Annual Scientific Congress, please visit:


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