Effects of anaesthesia and analgesia on long-term outcome after total knee replacement: A prospective, observational, multicentre study

Why still in hospital after fast-track hip and knee arthroplasty?

BACKGROUND AND PURPOSE

Length of stay (LOS) following total hip and knee arthroplasty (THA and TKA) has been reduced to about 3 days in fast-track setups with functional discharge criteria. Earlier studies have identified patient characteristics predicting LOS, but little is known about specific reasons for being hospitalized following fast-track THA and TKA.

PATIENTS AND METHODS

To determine clinical and logistical factors that keep patients in hospital for the first postoperative 24-72 hours, we performed a cohort study of consecutive, unselected patients undergoing unilateral primary THA (n = 98) or TKA (n = 109). Median length of stay was 2 days. Patients were operated with spinal anesthesia and received multimodal analgesia with paracetamol, a COX-2 inhibitor, and gabapentin-with opioid only on request. Fulfillment of functional discharge criteria was assessed twice daily and specified reasons for not allowing discharge were registered.

RESULTS

Pain, dizziness, and general weakness were the main clinical reasons for being hospitalized at 24 and 48 hours postoperatively while nausea, vomiting, confusion, and sedation delayed discharge to a minimal extent. Waiting for blood transfusion (when needed), for start of physiotherapy, and for postoperative radiographic examination delayed discharge in one fifth of the patients.

INTERPRETATION

Future efforts to enhance recovery and reduce length of stay after THA and TKA should focus on analgesia, prevention of orthostatism, and rapid recovery of muscle function.

Local infiltration analgesia in TKA patients reduces length of stay and postoperative pain scores

Numerous postoperative pain protocols exist for patients undergoing total knee arthroplasty (TKA). We compared the length of stay, early range of motion (ROM), and pain scores of a control group with a femoral nerve block to those of a group with femoral nerve block and local infiltration analgesia following TKA. In a consecutive series of patients undergoing primary TKA at a Veteran's Administration hospital, 40 patients (40 TKAs) who had local infiltration analgesia were compared to a historical group of 43 patients (43 TKAs) who had a long-acting femoral nerve block without local infiltration analgesia. Local infiltration analgesia consisted of intraoperative injection of 150 mL of 300 mg ropivacaine, 30 mg ketorolac, and 500 μg epinephrine using 50 mL into each of 3 areas: (1) posterior capsule, (2) medial and lateral capsule, and (3) anterior capsule and subcutaneous tissues. A 17-gauge intra-articular catheter was used to inject an additional 100 mg of ropivacaine on postoperative day 1. The control group had a single-shot femoral nerve block using 150 mg of ropivacaine with epinephrine. Mean length of stay for the local infiltration analgesia group compared to controls was 3.2±1.4 days vs 3.8±1.6 days, respectively (P=.03). No significant differences existed in average ROM (6 weeks), discharge hematocrit, transfusions, and temperature. Mean pain scores were lower in the local infiltration analgesia group on postoperative day 1 (P=.04), but not on postoperative day 2 or 3. Maximum visual analog scale scores (P<.01) were reduced in the local infiltration analgesia group. Our early experience with local infiltration analgesia demonstrated a significantly reduced length of stay due to decreased postoperative pain.