The factors determining early mobilization in elderly patients undergoing total knee replacement

Postoperative early mobilization after total knee replacement (TKR) is essential for preventing complications and offers numerous benefits. The purpose of this study was to evaluate the factors determining early mobilization (EM) after primary TKR and the effects on risk of falls and length of stay (LOS).

This retrospective study recruited elder participants undergoing primary TKR. All patients were classified as EM(+), early mobilization (EM) within 24 h, or EM(-), delayed mobilization over 24 h. Demographic data, pain Visual Analog Scale (VAS), American Society of Anesthesiologists (ASA) score, perioperative blood pressure, postoperative pain control mode, medical catheters, dizziness or nausea/vomiting (PONV), falls during admission, and the LOS were collected.

A total of 1759 elder participants undergoing primary TKR were enrolled. Mean age was 73.00 ± 8.11 years. Among them, there were 1260 EM(-) and 499 EM(+) cases, with no significant differences in sex, BMI, PONV, postoperative Patient Controlled Analgesia (PCA) mode, or the use of medical catheters, but age, higher ASA score, VAS, muscle strength, postoperative nausea, and substantial changes of blood pressure were significantly different between the two groups. A greater reduction in systolic blood pressure, when compared to the preoperative baseline blood pressure, was found in EM(-) patients than EM(+) patients on the operative day (13 vs. 4 mmHg, P < 0.001) and first day post-TKR (20 vs. 17 mmHg, P = 0.005). LOS in EM(-) patients was significant longer than that in EM(+) patients, but risk of falls was not significantly different.

Multiple factors influence patients' willingness to mobilize or ambulate earlier. However, more blood pressure reduction impeding early mobilization after TKR should be addressed. Maintaining post-TKR blood pressure without significant decreases is recommended for the successful mobilization after surgery. Early mobilization within 24 h after TKR may be beneficial in reducing the LOS and did not increase risk of falls.