After 3,721 Total Joint Replacements, One Thing Is Clear…

Routine postop chemistry panels are not necessary—at least that’s the conclusion of new research from the Rothman Orthopaedic Institute in Philadelphia.

After thousands of total knee and hip arthroplasty procedures, Rothman’s research team, noting the rising rate of short-stay procedures, published what they learned in a new study titled, “Routine Postoperative Chemistry Panels Are Not Necessary for Most Total Joint Arthroplasty Patients,” which now appears in the June 2, 2021, edition of The Journal of Bone and Joint Surgery.

“While this topic has been explored previously,” explained co-author Matthew Austin, M.D. to OTW, “the strength of our study was the relatively large cohort of patients and inclusion of both total hip and total knee patients.”

Along with colleagues, Dr. Austin, director of adult reconstruction at Rothman, looked at data from 3,162 patients who had been treated with 3,721 TJA (total joint arthroplasty) procedures of which 1,939 were total hip arthroplasty and 1,782 were total knees. All the patients were administered pre- and postoperative chem-7 testing (lab tests traditionally obtained after TJA).

And what did the authors learn from this study? Basically, the labs were not worth the time and cost. Specifically, quoting from the paper itself, the authors wrote, “Our findings indicate that an abnormal preoperative laboratory result, diabetes mellitus, renal disease, and/or prescribed ACE [angiotensin-converting enzyme]/ARBs [angiotensin receptor blockers] or diuretics are consistent risk factors for abnormal postoperative electrolyte results. The identification of specific risk factors in combination with the small variance of postoperative electrolyte results highlights the lack of need for routine chem-7 panels in the majority of patients undergoing TJA.”  [emphasis added]

Dr. Austin expanded on his published comments with OTW: “In this era of delivering cost-effective care, our study suggests that selective, patient-specific ordering of chemistry labs following TJA is safe. We would like to highlight that a select cohort of patients may benefit from postoperative chemistry labs. These include patients with abnormal preoperative chemistry labs or renal function, patients on medications that may affect renal function or bilateral TJA performed on the same day.”

“This large retrospective study suggests that routine labs after TJA may not be necessary for most patients. This is particularly relevant with the rise of same day discharge TJA as patients undergoing outpatient TJA do not undergo routine post-discharge lab testing.”