Letter to the Editor on “Hospital Discharge Within 1 Day After Total Joint Arthroplasty From a Veterans Affairs Hospital Does Not Increase Complication and Readmission Rates”

To the Editor:
Dear editor, we read with great interest the article by Kiskaddon et al. This is a very interesting study which intends to determine whether there is a difference between discharge on postoperative day 1 (POD 1) and after a longer in-hospital stay in patients who undergo primary total hip or knee arthroplasty [1].

Although this is a trending topic and the conclusion of the article is in line with the expectations of the medical community, we think that selection bias could have played a determinant role in the obtained results, therefore yielding a misleading conclusion.

First of all, patients underwent joint arthroplasty during different historical discharge policies, and it is possible that the second cohort of patients would have benefit of improved protocols such as spinal anesthesia (78% in subgroup 1 vs 11% in subgroup 2) as stated by authors within the Materials and Methods section.

Second, although preoperative patient characteristics seemed to be similar, it is clear that subgroup 1 had a lower proportion of patients in grade III and IV according to the American Society of Anesthesiologists Classification system (ASA); this could explain a longer hospital stay so it is clear that patients who were scheduled for discharge on POD 1 were selected upon some medical criteria that were not described in the Methods of this study.

According to the aforementioned reasons, the results of this study could be the result of a careful selection of patients for the early discharge group and an improved perioperative protocol by the time when discharge on POD 1 was implemented. Therefore, both the title and conclusions of this article might be an overstatement which could mislead the medical community to apply a protocol to general population instead of selecting patients.

Moreover, the selection criteria used by the authors to assign patients to early discharge group should be described because it is of cornerstone relevance for the readers who are willing to benefit their patients with the results of this study.