Is It Necessary to Wake Patients for Overnight Vital Signs Following Total Joint Arthroplasty?

Benefits of sleep are well-established in postoperative recovery; however, patients undergoing total joint arthroplasty (TJA) often experience poor sleep during hospitalization. While multifactorial, among the major reasons are the frequent and ritualized overnight vital sign checks. In the absence of data in support of or against this practice, we asked whether it remains necessary. We retrospectively analyzed a cohort of 419 primary TJA patients. Demographics, comorbidities, operative, and vital sign data were collected through postoperative Day 3. Correlation between daytime (6:00 a.m. to 10:00 p.m.) and nighttime (10:01 p.m. to 5:59 a.m.) vitals was examined. The vast majority of nighttime vitals fell within normal ranges, including O2 saturation (O2; 99.4%), temperature (TEMP; 97.8%), heart rate (HR; 87.5%), systolic blood pressure (SBP; 85.8%), and diastolic blood pressure (DBP; 84.4%). Predictors of abnormal nighttime vitals included American Society of Anesthesiologists (ASA) score (abnormal SBP; odds ratio [OR] 1.64, p = .045), obesity (abnormal DBP; OR: 0.37, p = .011), and smoking status (elevated temperature; OR: 2.79, p = .042). Estimated blood loss was predictive of an abnormal nighttime TEMP (OR: 1.002; p < .001). Postoperatively, there were several correlations between abnormal daytime and nighttime vitals, including SBP (OR: 6.23, p < .001), DBP (OR: 4.31, p < .001), and HR (OR: 10.35; p < .001). Of the 419 patients, only 9 (2.1%) received any intervention based on abnormal nighttime vitals. Each exhibited daytime vital sign abnormalities prior to the abnormal nighttime readings. Patients with abnormal nighttime vitals can be predicted on the basis of medical comorbidities and abnormal daytime vitals. These findings suggest that healthy post-TJA patients with normal daytime vitals may not need to be routinely woken at night.