Optimal Timing of Glucose Measurements After Total Joint Arthroplasty

Postoperative glucose levels after total joint arthroplasty are important to monitor as hyperglycemia has been linked to complications such as periprosthetic joint infection. The purposes of this study were to identify how postoperative glucose values vary during the perioperative period and determine the optimal time to check glucose levels to best evaluate for hyperglycemia. A retrospective study was conducted from September 2017 to September 2018 on 314 patients who underwent knee and hip arthroplasties. Blood glucose levels were collected immediately preoperatively, immediately postoperatively, at 5 PM on the day of surgery (DOS), at 9 PM on the DOS, and in the morning of postoperative day (POD) 1. The total number of hyperglycemic patients was assessed at 3 glucose thresholds: strict ≥ 126 mg/dL, intermediate ≥ 137 mg/dL, and lenient ≥ 180 mg/dL. Descriptive statistics were performed for each glucose time period, and adjusted comparisons were made between the mean glucose values and number of hyperglycemic patients at all time points. Mean (±95% confidence interval) glucose values were 105.7 ± 2.1 mg/dL preoperatively, 117.3 ± 2.5 mg/dL immediately postoperatively, 138.6 ± 4.3 mg/dL at 5 PM on the DOS, 142.9 ± 4.3 mg/dL at 9 PM on the DOS, and 116.7 ± 3.1 mg/dL in the morning of POD 1. Values measured at 5 PM and 9 PM were significantly higher than those measured at all other time points in both diabetics and nondiabetics (P < .001 for all). For all 3 hyperglycemia thresholds, the highest number of hyperglycemic patients was observed at 9 PM on the DOS: strict = 205 (65.3%) patients, intermediate = 177 (56.4%) patients; and lenient = 90 (28.7%) patients. Most patients who underwent total joint arthroplasty are hyperglycemic postoperatively, and 9 PM on the night of surgery may be the most sensitive time for detecting hyperglycemia in both diabetic and nondiabetic patients, in contrast to traditional POD 1 levels.