Take greater care, provide clinical context when using abbreviations

To prevent errors and misunderstandings, referring clinicians and radiologists must show more restraint when using abbreviations, a U.K. study has found.

Around 10,000 medical abbreviations exist, with about 16,000 different meanings, according to Dr. Shilpi Pal, a radiologist at Ninewells Hospital in Dundee and lead author of a scientific poster at RSNA 09. The dangers of abbreviations, however, were shown in a 2008 article in the Journal of the U.K. Medical Defence Union, which found that errors occur due to ambiguities in cases like TOF (tracheoesophageal fistula or tetralogy of Fallot), PID (pelvic inflammatory disease or prolapsed intervertebral disc).

“Many publications highlight the dangers of abbreviations in prescribing errors,” Pal said. “Intervention in reducing abbreviation usage in prescribing has been shown to make a difference. In a litigious society, it is important to ascertain errors due to abbreviations in all aspects of medicine.”

Different clinicians use different abbreviations to refer to the same process, and handwritten request forms may be ambiguous. In radiology, L-spine may be mistaken for C-spine, leading to the wrong exposure to the patient.

Among the most common abbreviations with multiple meanings are CS (cervical spine, Caesarean section, culture and sensitivity), MET (metronidazole, metastasis), AS (aortic stenosis, ankylosing spondylitis), PD (peritoneal dialysis, Parkinson’s disease), and AV (aortic valve, atrioventricular, arteriovenous). Likewise, radiotherapy may be shortened to XRT, RTx, RT, and DXT, while creatinine can be abbreviated to C, Cr, or Creat.

“To prevent harm to the patient, it is vital to ensure that the intended meaning is clear,” Pal said.

The authors analyzed 600 radiology request cards, consisting of 200 consecutive requests each for ultrasound, chest x-ray (CXR), and CT. They studied them for use of abbreviations and symbols. CT request cards contained significantly more abbreviations, but also had more words per card.

To understand the abbreviations, knowing the clinical context was essential in 13% of cases for chest x-ray, 11% for ultrasound, and 5% for CT. The review panel felt the clinical context was necessary for the following abbreviations: A/E (air entry, accident and emergency), PT (patient, prothrombin time), temp (temperature, temporary), B/L (bilateral, basal), Ca (calcium, cancer), C (cancer, creatinine), v (versus, venous), mm (malignant melanoma, multiple myeloma, millimeter), RT (radiotherapy, right), OA (on admission, osteoarthritis).

“All the intended meanings were evident when the clinical context was revealed,” Pal said. “We therefore conclude that abbreviations are a safe form of communication in radiology. The vast majority of abbreviations are readily comprehensible. However, there is a considerable legibility-dependent aspect if cards are handwritten, meaning that even accepted abbreviations may be misinterpreted.”

Due diligence by the referring clinician is vital, with careful use of abbreviations only where appropriate. Radiologists must contact clinicians when doubt persists, and it may even be worthwhile compiling a list of banned abbreviations in radiology, the authors concluded.