Background: Recent studies have shown that local infiltration analgesia (LIA) improves outcome after total hip replacement (THA). No detailed information does exist to its influence on length of stay (LOS) after surgery. In this study we have evaluated LOS, pain treatment, mobilization, postoperative nausea and vomiting (PONV) and satisfaction in a period before and after implementing LIA in our department.

Patients and Methods: Patients diagnosed with primary osteoarthrosis of the hip scheduled for unilateral uncemented or hybrid THA were included in the study. All cases were recognized from a local database with prospective collected data on all patients undergoing THA in our department. Total 100 consecutive patients who did not have LIA from September 1st 2006 were compared with 100 consecutive patients who received LIA from September 1st 2007. The two groups were unmatched and no patients were excluded. The solution used for LIA consisted of 200 mg Ropivacain, 30 mg Ketorolac and 1 mg Adrenaline dissolved in 100 ml isotone NaCl.

Results: Patients in the two groups were similar in regard to gender, age, body mass index (BMI) and ASA group, but did differ in duration of the surgical approach, the latter group having treatment with LIA in average had a 20 minuts shorter surgical approach. The patients who received LIA had reduced LOS, mean 3.8 days compared to 5.1 days in the gropu not treated with LIA (p< 0.001). Moreover, patients treated with LIA were significant more satisfied (p< 0.05) compared to the group who did not receive LIA. Moreover, patients treated with LIA were more frequently mobilized on day 1 after surgery (p< 0,001) and day 3 as well (p< 0.05). Also, patients treated with LIA had significantly reduced PONV on the day of operation (p< 0.05) and well as they consumed more nutrition (p< 0.001) the day after the operation. There was no difference in pain-score between the two groups except on day 3 (p< 0.05) in activity and at rest on the day of discharge (p< 0.05). No wound complications could be shown in any of the groups during the first 6 weeks after surgery.

Interpretation: Introducing LIA in our department changed the postoperative period detailed in several ways for patients undergoing THA. This study document that operative wound infiltration with multimodal drugs reduced LOS after THA, even though the reduced duration of operation may be some of the explanation. Moreover, LIA resulted in better mobilisation, less PONV and more satisfied patients. We recommend all unit undertaking THA to implement LIA in their daily praxis.